** **

**Exhibit 10.8**

**CONFIDENTIALTREATMENT REQUESTEDCONSOLIDATED AND RESTATED AMENDMENT TO DISTRIBUTORSHIP AGREEMENT**

**This Consolidated and Restated Amendment to DistributorshipAgreement (**this “Amendment”) is made and entered intoas of the ___ day of June, 2005 (the “Effective Date”) by and between **Patterson Companies, Inc**., a corporationorganized under the laws of the State of Minnesota (“Patterson”), and **Sirona Dental Systems GmbH**, a limitedliability company organized under the laws of the Federal Republic of Germany (“Sirona”).Patterson and Sirona are sometimes collectively referred to as the “Parties”and each individually as a “Party.”

**RECITALS:**

**WHEREAS**, the Parties entered into aDistributorship Agreement dated by Patterson April 24, 1998 and dated by SironaApril 27, 1998 (the “Distributorship Agreement”), a copy of which isattached to this Amendment and incorporated herein;

**WHEREAS**, the Parties entered into fiveagreements amending the Distributorship Agreement (together, the “PriorAmendments”), a copy of each of which is attached to this Amendment andincorporated herein;

**WHEREAS**, the Parties desire by thisAmendment to amend further the Distributorship Agreement and to consolidatethose further amendments with the Prior Amendments so that the DistributorshipAgreement, as modified by this Amendment, will be a fully-integrated agreementas of the Effective Date;

**NOW, THEREFORE**, in consideration of theabove premises and the mutual covenants in this Amendment, and for other goodand valuable consideration, given by each Party to the other, the sufficiencyand receipt of which are hereby acknowledged, the Parties, for themselves,their successors and permitted assigns, intending to be legally bound, agreethat the Distributorship Agreement be amended as follows:

## **I.              Extensionof Exclusivity. **Section17.1 of the Distributorship Agreement is deleted in its entirety and isreplaced by the following provision:

## Subject to thetermination provisions set forth in item VIII of this Agreement (including theduration of the exclusive provisions of the Distributorship Agreement), theDistributorship Amendment is extended through September 30, 2017; that is, tenyears beyond the period of exclusivity granted under the fifth of the PriorAmendments. Such ten-year extension will be deemed to be a new contract to takeeffect on October 1, 2007 if the Distributorship Agreement is in full force andeffect on September 30, 2007 and will be governed under the terms of thisAmendment.

## **II.            Paymentfor Extension of Exclusivity. **Pattersonwill make a one-time payment to Sirona of $100 million to be paid by wiretransfer by June 30, 2005 in consideration of the additional ten (10) years ofexclusivity granted by this Amendment. For all economic purposes, Patterson and Sirona agree that the $100million consideration will begin to be earned on October 1, 2007.

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# ** **

**CONFIDENTIALTREATMENT REQUESTED**

# **III.           Mutually Exclusive Arrangement.** Sections 1.3, 1.2 and 1.1 of theDistributorship Agreement are deleted in their entirety and are replaced by thefollowing provisions:

## **A.            “ContractualProducts”** means all current and future CAD-CAMequipment manufactured by Sirona, solely or principally to produce dentalrestorations in either the dental lab or in the dentist’s office.

Contractual Products will include activation keys,spare parts, and repair exchange parts. For the avoidance of doubt, ContractualProducts will not include services that use CAD-CAM technology such as Sirona’sinfiniDent service, “specialty customized CAD/CAM solutions,” or consumables,including, without limitation, blocks. For purposes of this item III.A, aspecialty customized CAD/CAM solution is a CAD/CAM product that is functionallydifferent from Contractual Products in a material way, including withoutlimitation custom modifications for individual customers, which difference hasthe practical affect of excluding such product from the broad end-user market.

During the term of the Distributorship Agreement,Patterson will have a right of first offer to be the exclusive distributor forSirona in the Territory of future CAD/CAM products designed solely orprincipally to produce dental restorations in either the Dental lab or in thedentist’s office, which products are acquired by Sirona from a third-party orare produced by Sirona, but which products are materially different (other thancosmetically) from Contractual Products and are not marketed under the Sironabrand.  The right of first offer shall beadministered as follows:

### 1.             BeforeSirona markets such products itself or through others, it will first deliver toPatterson a written offer prepared by Sirona (the “First Refusal Offer”),which will be irrevocable for a period of 30 calendar days after deliverythereof (the “First Refusal Offer Period”).  The First Refusal Offer will offer toPatterson, or at Patterson’s election, to an Affiliate (defined in item XII.A)of Patterson, the opportunity to enter into an exclusive arrangement withSirona with respect to such products in the Territory under the terms andconditions of the Distributorship Agreement (with applicable changes toconsideration and other economic provisions as proposed by Sirona and agreed byPatterson) for the then-remainder of the term of the Distributorship Agreement(the “First Refusal Terms”).

### 2.             Atany time prior to the expiration of the First Refusal Offer Period, Pattersonwill have the right to elect, by written notice to Sirona (the “FirstRefusal Acceptance Notice”), to enter into an amended DistributorshipAgreement as set forth in the First Refusal Terms.  If Patterson delivers the First RefusalAcceptance Notice prior to the expiration of the First Refusal Offer Period,Patterson and Sirona will negotiate in good faith to enter into the amendedDistributorship Agreement within 30 days after Patterson’s delivery of theFirst Refusal Acceptance Notice.

### 3.             If(i) Patterson fails to deliver the First Refusal Acceptance Notice prior to theexpiration of the First Refusal Offer Period, or (ii) if the Parties fail toenter in to an amended Distributorship Agreement within such 30-day periodafter such 

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### good-faith negotiations consistent with theFirst Refusal Terms as the Parties may agree to modify them, then, Sirona willbe permitted to distribute such products in the Territory either itself (orthrough a Sirona subsidiary or affiliate), or with an unrelated third-party onarms-length terms which are not materially more favorable to the applicablethird-party than the First Refusal Terms. If Sirona does not commence suchdistribution, itself or with such third-party within the 180-day periodimmediately after the expiration of the First Refusal Offer Period, then thedistribution of such products in the Territory will again become subject toPatterson’s right of first offer as set forth in this item III.A.

### 4.             Timewill be of the essence with respect to all time periods set forth in this itemIII.A.

Annex 1 to the Distributorship Agreement, as amended,is deleted in its entirety.  From time totime upon Patterson’s request, Sirona will deliver a list of the then-currentContractual Products.

## **B.            The“Territory”** covered by the Distributorship Agreementwill be the United States of America including its territories and possessions,and Canada, including all of its provinces.

## **C.            Sirona’sExclusive to Patterson. **Forso long as Patterson provides Sirona with the exclusivity described in itemIII.D, and subject to Sirona’s termination rights described in item VIII,Sirona grants to Patterson the exclusive right to distribute (itself or throughan Affiliate) Contractual Products solely in the Territory to end users.  The exclusive is subject to Sirona’s right todistribute (itself or through a subsidiary or affiliate) Contractual Productsto academic institutions and government agencies and facilities and to selldental restoration services.  Sirona willbe entitled to enlist Patterson’s help in providing technical services on afee-for-service basis.

## **D.            Patterson’sExclusive to Sirona. **Forso long as Sirona provides Patterson with the exclusivity described in itemIII.C, and subject to Patterson’s termination rights described in item VIII,Patterson will forbear from promoting or selling, directly or indirectly, inthe Territory any product that competes with Contractual Products or partstherefor.

# **IV.          **  **Dental LabProducts. **Patterson will useits best efforts to promote and sell Contractual Products to dental labs in theTerritory.  As such, Patterson willassure that not later than October 1, 2005 each local Patterson branch hasreadily available a demonstration unit for each type of Contractual Productoffered by Sirona specifically for dental lab use (“Dental Lab Products”).

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**[*] designatesportions of this document that have been omitted pursuant to a request forconfidential treatmentfiled separately with the Securities and Exchange Commission.**

# **V.            [*]. **Sirona intends to enter the market for [*]. For solong as [*] are competitive in quality and price, Patterson will use its bestefforts to ensure that [*] are marketed actively.

# **VI.           Patterson’s Minimum PurchaseRequirements. **Section2.4 of the Distributorship Agreement is deleted in its entirety and is replacedby the following provisions:

## **A.            MinimumPurchase Requirement. **Subjectto item VI.F, in each Sirona fiscal year (i.e., October 1 through September30), Patterson will purchase from Sirona the dollar volume of ContractualProducts (based on net invoice price to Patterson) as set forth in thefollowing Table adjusted as described in B, below.

**MINIMUM PURCHASEREQUIREMENTS TABLE**
| ** ** | **Sirona Fiscal  Year** | ** ** | **Total Annual   Minimum Purchase  Requirement for  eligible Contractual  Products (US $)** | ** ** | **Growth  from prior  year** | ** ** |
|------------|------------------------------|------------|--------------------------------------------------------------------------------------------------------------------------------|------------|-----------------------------------|------------|
|       | 2005/06                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2006/07                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2007/08                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2008/09                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2009/10                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2010/11                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2011/12                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2012/13                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2013/14                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2014/15                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2015/16                      |       | $[*]                                                                                                                           |       | [*]%                              |       |
|       | 2016/17                      |       | $[*]                                                                                                                           |       | [*]%                              |       |

 

## **B.        Adjustmentsto Annual Minimum Quantities.  **Subject to itemVI.F, for each Sirona fiscal year the minimum purchase requirement will be thehigher of (1) the minimum purchase requirement for such year as set forth inthe Table, or (2) the actual dollar volume of purchases (based on net invoiceprice to Patterson) of Contractual Products during the last Sirona fiscal yearplus [*]% of such actual dollar volume. The annual purchase requirement as setforth in the Table, as it may be adjusted by this provision, is referred to asthe “Minimum Purchase Requirement.”

## **C.            Easingthe****Minimum PurchaseRequirement.  **The Minimum Purchase Requirement may be adjustedto avoid Patterson being penalized for over-production or by unnecessary levelsof inventory. Therefore, the strict requirement of satisfying a MinimumPurchase Requirement will be eased by either of the following mechanisms:

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**[*] designatesportions of this document that have been omitted pursuant to a request for confidential treatment filed separatelywith the Securities and Exchange Commission.**

### 1.             If,in any Sirona fiscal year, the Minimum Purchase Requirement is not satisfied,it will nevertheless be deemed to be satisfied if Patterson’s actual dollarvolume of purchases of Contractual Products for such year, plus its actualdollar volume of purchases of Contractual Products during the last twopreceding Sirona fiscal years, is equal to or exceeds the total of the MinimumPurchase Requirements for such three years; or

### 2.             If,in any Sirona fiscal year, the Minimum Purchase Requirement is not satisfied by[*]% or less, it will nevertheless be deemed to be satisfied if: (i) in thenext succeeding Sirona fiscal year, the actual dollar volume of purchases ofContractual Products exceeds the Minimum Purchase Requirement for such year byat least the amount of the deficiency in the last preceding year; or (ii) thetotal of the actual dollar volume of purchases of Contractual Products in theyear of the deficiency plus the actual dollar volume of purchases ofContractual Products in the Sirona fiscal year immediately preceding and immediatelysubsequent to such year is equal to or exceeds the total of the MinimumPurchase Requirements for such three years.

## **D.            Some Purchases Are Not Counted.**   Someproducts will not be included in the computation of Minimum PurchaseRequirement or in the determination of whether a Minimum Purchase Requirementhas been satisfied, even if such products are Contractual Products. These arespare parts, repair exchange parts and activation keys. For the avoidance ofdoubt, consumables (including, without limitation, blocks), CEREC Clubrevenues, software revenues, and other services or maintenance revenues are notconsidered in the determination of whether a Minimum Purchase Requirement hasbeen satisfied.

## **E.             Minimum Monthly Orders fromPatterson.  **To help ensure even distribution ofSirona manufacturing capacity, Patterson agrees to place a firm order mandatingthat at least [*] of the Minimum Purchase Requirement in any year is deliveredto Patterson in each month of that year (the “Minimum Monthly Order”). For thepurposes of inventory reduction, Patterson may elect to skip one requiredMinimum Monthly Order per year with 90 days’ prior notice to Sirona.

## **F.            ****Special Rules for Fiscal Years 2005-2007.   **Notwithstandinganything in this Amendment to the contrary, for purposes of determining Sirona’srights of termination under item VIII.A.4 of this Amendment, the MinimumPurchase Requirements for Sirona fiscal years 2005/2006 and 2006/2007 will be$[*] and $[*], respectively, instead of the higher requirements set forth inthe above Minimum Purchase Requirements Table for such years. For all otherpurposes, the Minimum Purchase Requirements for Sirona fiscal years 2005/2006and 2006/2007 will be as set forth in such Table, including without limitation forcalculations, including those in C of this item VI, if a Sirona fiscal yearafter 2006/2007 is affected.

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**[*] designatesportions of this document that have been omitted pursuant to a request for confidential treatment filed separatelywith the Securities and Exchange Commission.**

# **VII.         Prices of Contractual Products.   **Section8.2 of the Distributorship Agreement is deleted in its entirety and is replacedby the following provisions:

## **A.            Current Prices andPrice Increases.   **Prices for ContractualProducts, spare parts, repair exchange parts, and accessories of ContractualProducts will continue at their current levels which will be set forth in Annex3. Annex 3 will be deemed amended at the time that the prices of newContractual Products are established or whenever prices of in-line ContractualProducts are changed, as follows:

### 1.             *New Contractual Products*.   Sironawill establish the price of new Contractual Products (i.e., ContractualProducts that have significantly improved functionality, or have differentfunctionality than existing products).

### 2.             *In-Line Contractual Products*.   Sironawill consider an annual price increase for in-line Contractual Products. Unlessthe Parties otherwise agree in writing, the price of each Contractual Productand each part and accessory for such Contractual Product will be increasedeffective October 1 of each year during the term of the DistributorshipAgreement beginning October 1, 2005 by the greater of: (i) [*]%; or (ii) theincrease over the prior year in the Consumer Price Index for All UrbanConsumers, U.S. City Average, Base 1982-84 = 100.

### 3.             *Exchange-Rate Effect*.   All priceswill be stated in U.S. dollars. For the purpose of this DistributorshipAgreement, the baseline exchange rate will be 1 Euro equals USD [*].  If there is a change in this exchange rateplus or minus an average of [*]% or more sustained over a rolling 30-day period(the “Trigger Event”), one of the following two effects shall occur:

#### (i)      Shouldthe US dollar depreciate by more than [*]% (i.e., less than 1 Euro equals [*]USD), Sirona will have the right to increase prices of Contractual Products, spareparts, repair exchange parts, and accessories of Contractual Products byapplying all or a part of the new exchange rate upon not less than 30 days’prior written notice to Patterson.

#### (ii)     Shouldthe US dollar appreciate by more than [*]% (i.e., greater than 1 Euro equals[*] USD), Sirona will credit Patterson with [*]% of the incremental revenue,calculated as set forth in the following sentence. Upon occurrence of theTrigger Event, incremental revenue to be so credited will be calculated on theday that Contractual Products that count toward the Minimum PurchaseRequirement (as described in item VI.D of this Amendment) are paid for byPatterson, by the formula: [*]**multipliedby (**[*]**, less the dollar exchangerate listed at noon CET on the Frankfurt currency exchange), multiplied by theprice paid for such  Contractual Products**.

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# **VIII.        Termination of the Agreement.  **Sections17.2 (including Subsections 17.2.1, 17.2.2 and 17.2.3), 17.3 (includingSubsections 17.3.1, 17.3.2 and 17.3.3) and 17.4 of the DistributorshipAgreement are deleted in their entirety and are replaced by the followingprovisions:

# **A.           Termination for Cause.  **TheDistributorship****Agreement willcontinue for its full term unless it is earlier terminated, as follows:   Patterson and Sirona may each terminate theDistributorship Agreement (or it may elect instead to terminate only the mutualgrants of exclusivity described in items III.C and D of this Amendment) upon writtennotice to the other with immediate effect due to the following occurring to (orin the case of a material breach committed by) the other Party:

### 1.             **Force Majeure.  **If an event of Force Majeure (definedin item XII.A),  occurs that hinders aParty’s performance under the Agreement for more than 6 months.

### 2.             **Bankruptcy.**   If either Sirona or Patterson becomesinsolvent, files or has filed against it a petition in bankruptcy, makes ageneral assignment for the benefit of its creditors, has a receiver or trusteeappointed for its business, properties or assets, and such petition, other thana petition filed by Sirona or Patterson, as the case may be, or appointment hasnot been dismissed or withdrawn for 90 business days.

### 3.             **Material Breach.  **If Sirona or Patterson is in seriousdefault of a payment obligation (including, without limitation, failure to paytimely an obligation more than 3 times in any Sirona fiscal year), or otherwisematerially breaches the Agreement. (A non-payment material breach is one that(i) is adverse to the essential business value of the Agreement because of itsserious nature or its redundancy, (ii) breaches an obligation ofconfidentiality under the Distributorship Agreement, (iii) infringes the otherParty’s intellectual property, or (iv) breaches an obligation under theDistributorship Agreement with respect to the other Party’s trademarks or otherintellectual property).  For non-paymentmaterial breaches, the non-breaching party will give notice of breach to the breachingparty and will provide 90 days to cure the breach if the breach is, in fact,capable of being cured within that period. Certain essential non-paymentmaterial breaches will be deemed non-curable and termination will be effectiveupon 30 days’ written notice, as follows:

#### (a)  ifSirona breaches its exclusive obligations to Patterson with respect toContractual Products, or, subject to Sirona’s rights described in the firstparagraph of item X, Sirona (x) discontinues the manufacture ofContractual Products or (y) fails to deliver material quantities ofContractual Products in accordance with confirmed delivery schedules by morethan 60 days more than 4 times in any Sirona fiscal year, each failure todeliver being wholly independent of the others, in either case of (x) or(y) other than as a result of an event of Force Majeure; and

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#### (b)  if (A) Patterson commits abreach described in (ii) through (iv) of this item VIII.A.3, or (B) Pattersonbreaches its exclusive obligations to Sirona with respect to ContractualProducts, or sells outside the Territory or sells to persons/entities otherthan end users, or (C) (x) ownership of 30.1% or more of the equity securitiesof Patterson entitled to vote or (y) the right to control the management orpolicies of Patterson is acquired (directly or indirectly) by a company thatcompetes with Sirona or any Sirona Affiliate that is engaged in the dentalequipment business, or (D) Patterson acquires (directly or indirectly) aninterest in a company that competes with Sirona or any Sirona Affiliate in anyof the dental equipment business lines currently engaged in by Sirona or suchAffiliate.

### **               **4**.             Underperformance.**

#### (i)      **Generally Regarding All Contractual Products.  **Subjectto item VI.F of this Amendment, if Patterson fails to satisfy the MinimumPurchase Requirement, after taking into account the adjustment mechanismsdescribed in item VI.C of this Amendment (“Underperformance”), then Sirona, andonly Sirona, may exercise its termination rights hereunder upon 90 days’ noticeto Patterson. Given the significant period of time over which Underperformancedevelops, such breach is not deemed capable of cure.  Sirona’s sole remedy for Patterson’sUnderperformance shall be the exercise of its termination rights, and Pattersonshall not be liable for damages resulting solely from its Underperformance.

#### (ii)     **Dental Lab Products.  **Sirona will have the specialright to terminate the exclusivity to Patterson solely with respect toContractual Products comprised of Dental Lab Products if Patterson exits themarket for Dental Lab Products or fails to satisfy its obligations under itemIV of this Amendment. This limited termination of exclusivity will be Sirona’ssole remedy in the event of such breach by Patterson.

#### (iii)    **Underperformance is a no-fault concept.**   Aside fromfailing to meet the Minimum Purchase Requirement as a result of a willfulbreach (which shall be deemed to be a material breach), it does not matterwhether the Underperformance described in (i) or (ii) of this item VIII.A.4 isdue to market conditions or the noncompetitive nature of Contractual Productsor other cause.

**B.   Exclusive Remedies.**   Termination of theDistributorship Agreement or the rights of exclusivity or thereunder,  as provided in this item VIII, and liquidatedor other damages as provided in item IX below, are the exclusive remediesavailable to the Parties under this Agreement, at law or otherwise for breachof the Distributorship Agreement, *exceptthat*, either Party may also seek equitable relief if the other Partybreaches its obligations of confidentiality under the DistributorshipAgreement, infringes the other 

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Party’s intellectual property or breaches any of itsobligations under the Distributorship Agreement with respect to the other Party’strademarks or other intellectual property.

# **IX**.           **LiquidatedDamages****.**   Subsections15.1 and 15.2 of the Distributorship Agreement are deleted in their entiretyand are replaced by the following provisions:

## **A.            GeneralConcept.  **All of the for-cause terminationsdescribed in item VIII of this Amendment result in liquidated damages, except amaterial breach by Patterson or the occurrence to Patterson of an eventdescribed in item VIII.A.2 will not give rise to liquidated damages. In thecase of material breach by Patterson, Sirona will not have the benefit ofliquidated damages and will have to prove its actual damages, subject to thelimitations described in E of this item IX, and subject to the limitation thattermination of this Agreement or the right of exclusivity is the sole remedy ofSirona for Patterson’s Underperformance. This Amendment establishes twoschedules of liquidated damage, each of which contemplates a partial return toPatterson of the consideration described in item II of this Amendment paid byPatterson. Schedule I approximates a straight-line amortization of theconsideration, and Schedule II establishes an accelerated depreciation scheduleintended to approximate the value earned by Sirona.  Liquidated damages will be paid, in Sirona’ssole, absolute discretion, either in cash, or in preferred equity certificates(“PECs”) or equivalent junior subordinated promissory notes, as described in Cof this item IX. The Liquidated Damage Schedules follow:

## **Liquidated Damage Schedules**

| ** ** | ** ** | ** **                                                                | ** ** | **SCHEDULE I**                           | ** ** | **SCHEDULE II**                         | ** ** |
|------------|------------|---------------------------------------------------------------------------|------------|------------------------------------------|------------|-----------------------------------------|------------|
| ** ** | ** ** | **Effective Date of  Termination within   Sirona Fiscal Year  ending in** | ** ** | **Nominal value of  PECs  To be Issued** | ** ** | **Nominal value of PECs  To be Issued** | ** ** |
|       |       | 2005-2007                                                                 |       | $100 million                             |       | $100 million                            |       |
|       |       | 2008                                                                      |       | $90 million                              |       | $85 million                             |       |
|       |       | 2009                                                                      |       | $80 million                              |       | $70 million                             |       |
|       |       | 2010                                                                      |       | $70 million                              |       | $55 million                             |       |
|       |       | 2011                                                                      |       | $60 million                              |       | $40 million                             |       |
|       |       | 2012                                                                      |       | $50 million                              |       | $25 million                             |       |
|       |       | 2013                                                                      |       | $40 million                              |       | $20 million                             |       |
|       |       | 2014                                                                      |       | $30 million                              |       | $15 million                             |       |
|       |       | 2015                                                                      |       | $20 million                              |       | $10 million                             |       |
|       |       | 2016                                                                      |       | $10 million                              |       | $5 million                              |       |
|       |       | 2017                                                                      |       | $0                                       |       | $0                                      |       |

 

## **B.            Availabilityof Liquidated Damages.**

 

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### 1.             ScheduleI liquidated damages will be available only upon termination of theDistributorship Agreement by Patterson due to a material breach by Sirona asdescribed in item VIII.A.3 of this Amendment.

### 2.             ScheduleII liquidated damages will be available only upon termination of theDistributorship Agreement for the following reasons:

#### (i)      inthe event of termination by either Sirona or Patterson as a result of ForceMajeure (*except that*, if suchtermination by Sirona is for an event of Force Majeure that manifests in thefailure of Patterson to pay for Contractual Products actually ordered anddelivered, such liquidated damages will be offset by the money owed byPatterson to Sirona);

#### (ii)     inthe event of termination by Patterson upon the occurrence to Sirona of an eventdescribed in item VIII.A.2; or

#### (iii)    inthe event of termination by Sirona as a result of Underperformance byPatterson.

## **C.            PECs.  **PECs****are securities in Sirona’s ultimate parent entity, SironaHoldings LuxCo SCA, or a subsidiary. PECs will have the following characteristics: PECs rank senior inliquidation to any of the securities of Sirona’s parent held by MadisonDearborn Partners, and accrue a cumulative PIK yield of 8% per annum,compounded annually (or the equivalent in cash if Sirona elects to payliquidated damages in cash).  PECs have ascheduled redemption date one year past the scheduled maturity date of Sirona’ssenior and mezzanine indebtedness. PECs issued as liquidated damages will notbe transferable.  To the extent permittedby Sirona’s senior and mezzanine indebtedness, PECs will be subject to earlierredemption for cash at the option of Sirona’s parent. Sirona’s parent will notbe permitted to make any dividend payment to, or capital redemption from any ofMadison Dearborn Partners, Beecken Petty O’Keefe & Company or managementinvestors (the “Investors”) in respect of the Investors’ investments in Sirona’sparent or any fee or other distribution to the Investors other than (i)customary management and advisory fees and costs payable to the Investors and(ii) redemptions of share capital and quasi-equity investments of managementinvestors as required pursuant to Sirona’s parent’s contractual obligations tothe management investors. Notwithstanding the foregoing, if Sirona concludes that it would be taxinefficient to Sirona for its ultimate parent to issue PECs, then Sirona may,in lieu thereof, issue or cause an affiliate to issue, an equivalent amount ofjunior subordinated promissory notes that contain substantially identicalrights, terms, obligations and preferences as those of the PECs, in which caseall references herein to PECs shall mean and include such junior subordinatedpromissory notes.

## **D.            SpecialPayment of Liquidated Damages in The Event of Certain Material Breaches bySirona.  **In the event that Schedule I LiquidatedDamages are due to Patterson under item VIII.A.3 of this Amendment due to (1) agrant by Sirona to any other person or entity of distribution rights thatcontravene Sirona’s exclusivity obligations to Patterson under item III.C, or(2) the sale by Sirona or a  subsidiaryof 

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## Contractual Products in the Territory other than as permitted underitem VIII.C, each a “Special Breach,” then, notwithstanding anything in thisAmendment to the contrary: (i) if such liquidated damages are payable as aresult of a Special Breach that occurs during the term of this DistributorshipAgreement on or before September 30, 2007, such liquidated damages will be paidin cash (USD); and (ii) if such liquidated damages are payable as a result of aSpecial Breach that occurs during the term of this Distributorship Agreement onor after October 1, 2007, such liquidated damages will be paid by asubordinated note (the “Sub Note”) to be issued by Sirona’s ultimate parententity, Sirona Holdings LuxCo SCA, or a subsidiary. The Sub Note will be in theform substantially as set forth in Annex 1 to this item IX.D, attached heretoand incorporated herein.

## **E.             Characteristicsof Liquidated Damages.  **Liquidated damages havethe following attributes:

### 1.             Liquidateddamages are only available upon termination of the Distributorship Agreement,or the rights of exclusivity thereunder, for cause as described in B of thisitem IX.

### 2.            Where liquidated damages are available, no other damages will be available.

### 3.             Exceptfor liquidated damages, Patterson will not be entitled to any return of theconsideration described in item II of this Amendment paid by it.

### 4.             Liquidateddamages are not penalties, but are agreed damages constituting a reasonableapproximation of the loss to Patterson in the event of the applicable breach orevent giving rise to them.

## **F.             OtherRelevant Damage Concepts.**

### 1.             Otherthan as provided in this item IX, neither Patterson nor Sirona will have anyright to damages of any nature for breaches of the DistributorshipAgreement.  For the avoidance of doubt,Sirona will have no liability for damages of any nature other than liquidateddamages provided under this item IX, and Sirona will have the right to offsetagainst liquidated damages sums owed by Patterson for Contractual Productsactually ordered and delivered. During the cure period for a material breachcapable of cure, the Parties will consult with one another in order to fullyunderstand the nature of the breach and the requirements for its cure.

### 2.             Exceptwith respect to the infringement by Patterson of Sirona’s intellectual propertyrights, or breach by Patterson of its obligations under the DistributorshipAgreement relating to Sirona’s confidential information or intellectualproperty, including without limitation the Sirona trademarks, in no event willPatterson be liable to Sirona for indirect, special, punitive or consequentialdamages, including without limitation, loss of profits, arising from any causewhatsoever. Subject to items VIII.A.1, 2 and 4, in no event will either 

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### Party be liable for a breach of theDistributorship Agreement caused by an event of Force Majeure other than breachof the obligation of Patterson to pay for Contractual Products actually orderedand delivered, to which Force Majeure will not apply).

# **X.            Protectionagainst Technical Obsolescence.**

## **A.            Change in TechnicalSpecifications.**   Notwithstanding anything in theDistributorship Agreement to the contrary, Sirona reserves the right to changethe technical specifications of Contractual Products and to discontinue themanufacture and/or sale of Contractual Products in the ordinary course ofbusiness in connection with upgrading or creating new versions or models ofContractual Products or as required by law.

**B.**                                     **Notice to Patterson.**   Subject to A ofthis item X, Sirona agrees that it will give to Patterson at least 5 months’prior notice of the market introduction of any major functionality change to aContractual Product to allow sufficient time for Patterson to deplete itsthen-current inventory.  A “MajorFunctionality Change” is defined as: (1) a hardware change that will (x)significantly expand the range of indication for the user, or (y) enable theoperation of a software program that is scheduled to be released within the 5months following the hardware change; or (2) a software upgrade that will notoperate on a version of the hardware that has been delivered to Patterson inthe 5- month period prior to introduction of the upgrade. ** **IfSirona provides Patterson with the aforesaid notice, then, during the 3-month period prior to the rollout of theMajor Functionality Change, at Patterson’s election (a) Sirona will providePatterson with an upgrade at no charge so that the product received byPatterson during such 3-month period will meet the specifications of the MajorFunctionality Change; or (b) Patterson may refuse further shipments of thethen-current product until the earlier of (x) the time when the product with the Major Functionality Change isavailable, or (y) a product that can be upgraded to a product that will meetthe specifications of the Major Functionality Change is available.  If the aforesaid 5-month notice is not given,then, as Patterson’s sole and exclusive remedy, Sirona will, in it solediscretion, update or replace, free of charge, any non-compatible ContractualProducts delivered to Patterson during the 5-month period prior to the rolloutof the Major Functionality Change.

**XI.          Future Market Penetration.**

**A.          Determinationof a Restricted Market.  **Sirona and Patterson will meetin the event that either of them notifies the other that it believes thatfuture growth of the market for Contractual Products in the Territory is beingrestricted by limited access to the market. If Sirona and Patterson agree thatsuch restriction exists, the exclusive granted to Patterson by Sirona and theexclusive granted to Sirona by Patterson will terminate, the DistributorshipAgreement will be modified as agreed by the Parties to reflect suchtermination, and Contractual Products will be offered by Sirona in a widerdistribution.

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**CONFIDENTIALTREATMENT REQUESTED[*] designates portions of this document that have been omitted pursuant to arequest forconfidential treatment filed separately with the Securities and ExchangeCommission.**

**B.            Ending theExclusive.**   In anyevent, once Patterson purchases a dollar amount of Contractual Products that isgreater than the cumulative 12-year dollar amount of the Total Annual MinimumPurchase Requirements for Contractual Products eligible to be counted underitem VI.D of this Amendment, Sirona will have the absolute right to terminatesuch exclusive and implement broader distribution. However, before making thatdetermination, Sirona will consult with Patterson to discuss, among otherthings, modifications to the Distributorship Agreement as a result of suchtermination.

**C.            Special Commission to Patterson.  **Ifwider distribution is implemented under A or B of this item XI , Sirona willpay to Patterson a commission of [*]% of the net wholesale price of****Contractual Products that are included inthe computation of the Minimum Purchase Requirement, are sold through channelsother than Patterson and not by Sirona itself (as permitted under item III.C),and are sold in the Territory during the portion of the term of theDistributorship Agreement remaining after such wider distribution isimplemented. This commission will be paid in consideration of Pattersonproviding advice and assistance to Sirona in its wider distribution efforts.Such payment will be the sole and exclusive right and remedy of Patterson forcompensation arising out of the termination of the exclusive arrangement, andthe remaining applicable terms of this Distribution Agreement will remain infull force and effect.

**XII.         AdditionalProvisions.**

**A.         Additional Definitions.   **In additionto the definitions set forth in this Amendment, for purposes of theDistributorship Agreement, the following terms when capitalized will have themeanings set forth below when :

### 1.             “Affiliate” means, withrespect to any specified person or entity, any other person or entity thatdirectly or indirectly controls, or is under common control with, or is ownedor controlled by, the specified person, and, with respect to the person orentity to be determined hereunder to be a Patterson Affiliate, is engaged inthe distribution of dental equipment and supplies. For purposes of thisdefinition, “control”, with respect to any specified person, refers either to(i) the beneficial ownership of 50.1% or more of all classes of equitysecurities with voting rights issued by such person, or (ii) the power todirect the management and policies of the specified person by contract orotherwise.

### 2.             “Force Majeure” means an act of Godor the public enemy, riots, accidents, strikes or differences with labor, laborshortage, inability to obtain material, equipment, transportation or fuel,epidemics, quarantine, restrictions, unusually severe weather, compliance withor the operation of any applicable legislation, regulation, directive, order orruling of any government, or political subdivision or agency thereof, judgmentsor orders of any court of competent jurisdiction, or any other event beyond thereasonable control of the Party claiming benefit of Force Majeure, whether ornot similar to the foregoing causes.

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**CONFIDENTIALTREATMENT REQUESTED**

**B.            Third Party Licenses; Graymarket Goods.**   Inthe event Sirona licenses significant aspects of its technology or otherintellectual property related to Contractual Products that would enable anotherparty to produce, distribute or sell CAD-CAM equipment to make dentalrestorations in either the dental lab or in the dentist’s office, Sirona shallprovide in the license agreement or other arrangement that such equipment willnot be marketed, distributed or sold by such licensee in the Territory, andSirona shall use its reasonable commercial efforts to enforce such provision. The breach by Sirona of its obligations in this itemXII.B will be deemed a material breach under item VIII.A.3; *provided that,*the cure period with respect to such breachwill be 180 days rather than 90 days. In the event that Patterson alleges abreach of Sirona’s obligation hereunder to use reasonable commercial efforts toenforce such provision, Patterson will cooperate with Sirona in effecting suchcure. For the avoidance of doubt, the Parties agree that if a court awards royaltiesto Sirona as damages for breach by a third-party of such technology orintellectual property, such award will not be a breach of this item XII.B.

For the avoidance of doubt, the Parties understandthat (1) Graymarket Contractual Products may be promoted for distribution anddistributed in the Territory by persons unauthorized by Sirona; and (2) suchdistribution is not a breach by Sirona of its obligations under the Distributorship Agreement. The Parties willcooperate with one another and with U.S. governmental authorities in any actionthat may be taken by such authorities or either Party to prevent GraymarketContractual Products in the Territory.

**C.             SuccessorsBound.  **This Amendment and the Distributorship Agreementshall inure to the benefit of and be binding upon the successors to theParties.

**D.             Headings;Negotiation.**   Thecaptions, headings and titles used in this Amendment are for convenience ofreference only and will not affect in any way the meaning or interpretation ofthis Amendment. This Amendment is the result of arms-length negotiation and,accordingly, no presumption or burden of proof will arise with respect to anyambiguity or question of intent concerning this Amendment favoring ordisfavoring either Party by virtue of the authorship of any provision hereof.

**E.              Counterparts.  **This Amendment may be executed in multiplecounterparts, which shall be deemed to be one and the same instrument and eachof which shall be deemed enforceable without production of the others.

Except as expresslymodified by this Amendment (including its recitals and attachments), all of theterms, conditions, and agreements contained in the Distributorship Agreement,including the Annexes to the Distributorship Agreement that remain in effect,are hereby ratified and confirmed and shall remain in full force and effect inaccordance with their terms. This Amendment, together with its recitals and theDistributorship Agreement, sets forth the entire agreement between the Partieswith respect to the subject matter hereof and supersedes and cancels any and alloral and written prior agreements (other than the Distributorship Agreement)and all contemporaneous oral agreements between them, express or implied, withrespect to such subject matter, including without limitation the PriorAmendments which will be of no further force or effect. The Parties acknowledgethat no representations or promises have been made to induce either of them toenter into this Agreement other than as may be specifically set forth in thisAmendment.

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**CONFIDENTIALTREATMENT REQUESTED**

**IN WITNESS WHEREOF**, each of the Parties hascaused this Amendment to be signed on its behalf by its duly authorizedrepresentative(s) as of the Effective Date.

.                       
|        | Patterson  Companies, Inc. |   | Sirona Dental Systems GmbH |   |   |   |
|--------|----------------------------|--------|----------------------------|--------|--------|--------|
|   |                       |   |                       |   |   |   |
|   | By:__________________      |   | By:_____________________   |   |   |   |
|   |                       |   |                       |   |   |   |
|   | James W.Wiltz              |   | Jost Fischer               |   |   |   |
|   |                       |   |                       |   |   |   |
|   | Chief Executive  Officer   |   | Chief Executive  Officer   |   |   |   |
|   |                       |   |                       |   |   |   |

 

For good and valuableconsideration, the sufficiency and receipt of which is hereby acknowledged,**Sirona Holdings LuxCo SCA**, the ultimate parent entity ofSirona, signs this Amendment for the sole limited purpose of making thefollowing covenant and for no other purpose whatsoever including, withoutlimitation, assuming or becoming a party to or liable for any other obligationor any liability under the Distributorship Agreement as amended by thisAmendment:  Sirona Holdings LuxCo SCAhereby agrees to issue PECs or the Sub Note, as described in items IX.C and Dof this Amendment, respectively, if it is determined that it is to be theissuer thereof, and to comply with the dividend and capital redemptionlimitations described in item IX.C in respect of the PECs, if issued.
|   |                       |   |
|--------|----------------------------|--------|
|   | Sirona  Holdings LuxCo SCA |   |
|   |                       |   |
|   | By:____________________    |   |
|   | Name:__________________    |   |
|   | Title:__________________   |   |
|   |                       |   |

 

 

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**CONFIDENTIALTREATMENT REQUESTED**

**Annex 1 to Item IX. D**

**Form of Subordinated Promissory Note**

**SUBORDINATED PROMISSORYNOTE**

THIS INSTRUMENT AND THERIGHTS AND OBLIGATIONS EVIDENCED HEREBY ARE SUBORDINATE IN THE MANNER AND TOTHE EXTENT SET FORTH IN THAT CERTAIN INTERCREDITOR AGREEMENT (THE “INTERCREDITORAGREEMENT”) DATED AS OF[          ], 2005 BY ANDAMONG[                             ](THE “COMPANY”) AND[                             ],(“SENIOR LENDER”), AS LENDER PURSUANT TO THAT CERTAIN SENIOR CREDIT AGREEMENTDATED AS OF [         ], 2005 BYAND AMONG THE COMPANY, AND [                                ],  (“MEZZANINE LENDER”) AS LENDER PURSUANT TOTHAT CERTAIN MEZZANINE CREDIT AGREEMENT DATED AS OF[         ], 2005, AS SUCH CREDITAGREEMENTS HAVE BEEN AND HEREAFTER MAY BE AMENDED, RESTATED, SUPPLEMENTED OROTHERWISE MODIFIED FROM TIME TO TIME AND TO INDEBTEDNESS REFINANCING THEINDEBTEDNESS UNDER THOSE AGREEMENTS AS CONTEMPLATED BY THE INTERCREDITORAGREEMENT; AND EACH HOLDER OF THIS INSTRUMENT, BY ITS ACCEPTANCE HEREOF,IRREVOCABLY AGREES TO BE BOUND BY THE PROVISIONS OF THE INTERCREDITORAGREEMENT.

THIS NOTE HAS NOT BEENREGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWSOF ANY STATE AND MAY NOT BE SOLD, TRANSFERRED, OR OTHERWISE DISPOSED OF EXCEPTPURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND APPLICABLESTATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION FROM THEREGISTRATION REQUIREMENTS OF SUCH ACT AND SUCH LAWS.

**SIRONAHOLDINGS LUXCO SCA OR A SUBSIDIARY THEREOF**

**SUBORDINATEDPROMISSORY NOTE**
| [Amount]

  | [Place]  [Date] |
|------------------|-----------------|

 

FOR VALUE RECEIVED, theundersigned, [  ] (“**Issuer**”),a company incorporated in [  ], herebypromises to pay to the order of Patterson Companies, Inc. or its registeredassigns (the “**Holder**”), the principal sum of [          ]on June 30, 2016 (the “**Maturity Date**”)with interest thereon from time to time as provided herein.

# Interest.  The Issuer promises to pay interest (“**Interest**”) on the principal amountof this Note (including any Basic Interest and PIK Interest added to theprincipal amount of this Note as provided in Sections 1(a) and 1(b) below) (the“**Interest Rate**”).  Interest on this Note shall accrue from andincluding the date of issuance through and until repayment of the principalamount of this Note and payment of all Interest in full, and shall be computedon the basis of a 360-day year of twelve 30-day months (actual/360basis).  Interest shall be paid asfollows:

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##  

**CONFIDENTIALTREATMENT REQUESTED**

## Basic Interest.  The Issuer shall pay Interest (“**Basic Interest**”) on the principal amount of this Noteat the rate of 8% per annum, semi-annually in arrears until the Maturity Dateon June 30 and December 31 of each year or, if any such date shall not be abusiness day, on the next succeeding business day to occur after such date(each date upon which Basic Interest shall be so payable, an “**Interest Payment Date**”), beginning on the date ofthis Note, by wire transfer of immediately available funds to an account at abank designated in writing by the Holder; provided that if for any reason anyportion of any such payment of Basic Interest is not made on the applicableInterest Payment Date, the amount of Basic Interest not so paid shall be addedto the principal amount of this Note until such time as such Basic Interest ispaid.  In the absence of any such writtendesignation, any such Interest payment shall be deemed made on the date a checkin the applicable amount payable to the order of Holder is received by the Holderat its last address as reflected in Issuer’s note register; if no such addressappears, then to such Holder in care of the last address in such note registerof any predecessor holder of this Note (or its predecessor).

## PIK Interest.  In addition to Basic Interest, the Issuershall pay Interest (“**PIK Interest**”) on the principalamount of this Note at a rate of US LIBOR per annum plus 2% per annum,semi-annually in arrears until the Final Maturity Date on each Interest PaymentDate, beginning on the date of this Note, by adding an amount equal to theaggregate accrued but unpaid PIK Interest as of such Interest Payment Date tothe principal amount of this Note.

## No UsuriousInterest.  Inthe event that any interest rate(s) provided for in this Section 1 shallbe determined to be unlawful, such interest rate(s) shall be computed at thehighest rate permitted by applicable law. Any payment by the Issuer of any interest amount in excess of thatpermitted by law shall be considered a mistake, with the excess being appliedto the principal amount of this Note without prepayment premium or penalty; ifno such principal amount is outstanding, such excess shall be returned toIssuer.

# Optional Prepayment.  Issuer shall be permitted at any time andfrom time to time to prepay all or a portion of the principal and accruedInterest on the Notes at any time without any prepayment fee or penalty.

# Mandatory Prepayment.  Upon the occurrence of a Change of Controlthe Issuer shall prepay all of the Principal and Accrued Interest on the Note.

# Acceleration.  On the occurrence of an Event of Default ofthe type referred to in paragraph (d) of the definition of Event of Defaultwhich is continuing, the outstanding principal of and all accrued Interest onthis Note shall automatically become immediately due and payable, withoutpresentment, demand, protest or notice of any kind, all of which are herebyexpressly waived.  On the occurrence ofan Event of Default other than of the type referred to in paragraph (d) of thedefinition of Event of Default which is continuing, the holder of this Note maydeclare the outstanding principal of and all accrued Interest on this Note tobecome immediately due and payable, without presentment, demand, protest ornotice of any kind, all of which are hereby expressly waived.

“**Event of Default**” meansany of the following events:
|   | 17 |   |
|--------|----|--------|

 

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**CONFIDENTIALTREATMENT REQUESTED**

(a)                                  Non-payment.  The Issuer does not pay on thedue date any amount payable pursuant to this Note and such payment is not madewithin 20 Business Days of notice given by the Holder of such failure.

(b)                                 Breach of Undertakings.  TheIssuer breaches any other obligations it has given under this Note, however, noEvent of Default will occur if the failure to comply is capable of remedy andis remedied within 40 Business Days of the Holder giving notice to the Issuer.

(c)                                  Cross default.

(i)                                     AnyFinancial Indebtedness of any member of the Group under the Senior or MezzanineFacilities or otherwise but in any case in excess of EURO 40,000,000 inaggregate is declared to be or otherwise becomes due and payable prior to itsspecified maturity as a result of an event of default (however described).

(ii)                                  Anycreditor of the Issuer becomes entitled to declare any Financial Indebtednessof any member of the Group under the Senior or Mezzanine Facilities orotherwise but in any case in excess of EURO 40,000,000 in aggregate due andpayable prior to its specified maturity as a result of an event of default(however described).

(d)                                 Insolvency.   The Issuer is unable or admitsinability to pay its debts as they fall due or is deemed or declared underapplicable law to be unable to pay its debts or suspends making payments on itsdebts generally or a moratorium is declared in respect of any indebtedness ofthe Issuer.

(e)                                  Unlawfulness and invalidity.

(i)                                     Itis or becomes unlawful for the Issuer to perform any of its materialobligations under this Note.

(ii)                                  Anyobligation or obligations of the Issuer are not or cease to be legal, valid,binding or enforceable and the cessation individually or cumulativelymaterially and adversely effects the interests of the Holder under this Note.

(iii)                               ThisNote ceases to be in full force and effect or any subordination created underthe Intercreditor Agreement ceases to be legal, valid, binding, enforceable oreffective.

(f)                                    Repudiation.  The Issuer repudiates thisNote.

(g)                                 Cessation of Business.  TheGroup as a whole ceases to carry on its business.

# Information Rights.    The Issuer shall supply to the Holder:

|   | 18 |   |
|--------|----|--------|

 

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**CONFIDENTIALTREATMENT REQUESTED**

(i)                               assoon as they are available, but in any event within 120 days after the end ofeach of its financial years its audited consolidated financial statements forthat financial year; and

(ii)                                  assoon as they are available, but in any event within 45 days after the end ofeach financial quarter, its unaudited management accounts for that financialquarter including in each case profit and loss accounts, balance sheet and cashflow statements and a management commentary thereon.

# Dividends and share capital redemptions

## Sirona HoldingsLuxCo SCA shall not:

(i)                                     declare,make or pay any dividend (or interest on any unpaid dividend) (whether in cashor in kind) on or in respect of its share capital (or any class of its sharecapital); or

(ii)                                  repayor distribute any dividend or share premium reserve; or

(iii)                               payany fee or other distribution to its shareholders other than customarymanagement and advisory fees and costs payable to the Investors.

## SironaHoldings LuxCo SCA shall not make a redemption, repurchase, retirement,disposal, return, repayment or reduction of its share capital or quasi-equityor any redemption or reduction of its capital redemption or quasi-equity orother reserve except in respect of share capital or quasi-equity held bymembers of management of the Group as required pursuant to Sirona’s parent’scontractual obligations to such members of management.

# Security.  This Note and the obligations containedherein are unsecured and will not be supported by guarantees from any member ofthe Group.

# Subordination.  The Note will be subordinated only to theSenior Facilities and the Mezzanine Facilities (as the same may be amended,restated, refinanced, supplemented or otherwise modified from time to time) onterms to be negotiated with the agents for the Senior Facilities and theMezzanine Facilities (but on the basis that if any enforcement action ispermitted by the Noteholder prior to repayment and discharge in full of theSenior and the Mezzanine Facilities, the proceeds of such enforcement will berequired to be turned over to the agents for the Senior and the MezzanineLenders).

## Register;Assignment.  TheIssuer shall maintain a register (the “**Note Register**”) in its principaloffices for the purpose of registering the Note and any transfer or partialtransfer thereof, which register shall reflect and identify, at all times, theownership of record of any interest in the Note.  Upon the issuance of this Note, the Issuershall record the name and address of the initial purchaser of this Note in theNote Register as the first Holder.  Uponsurrender for registration of transfer or exchange of this Note at theprincipal offices of the Issuer, the Issuer shall, at its expense, execute anddeliver one or more new Notes of like tenor and of denominations of at least $1,000 (except as may be necessary toreflect any principal amount not 

|   | 19 |   |
|--------|----|--------|

 

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**CONFIDENTIALTREATMENT REQUESTED**

evenly divisible by $1,000)****of a likeaggregate principal amount, registered in the name of the Holder or atransferee or transferees.  Every Notesurrendered for registration of transfer or exchange shall be duly endorsed, orbe accompanied by written instrument of transfer duly executed by the Holder ofsuch Note or such holder’s attorney duly authorized in writing.  This Note may be transferred or assigned, inwhole or in part, by the Holder at any time with the prior written consent ofthe Holder.

# Replacement of Note.  On receipt by the Issuer of an affidavit ofan authorized representative of the Holder stating the circumstances of theloss, theft, destruction or mutilation of this Note (and in the case of anysuch mutilation, on surrender and cancellation of such Note), the Issuer, atits expense, will promptly execute and deliver, in lieu thereof, a new Note oflike tenor.  If required by the Issuer,such Holder must provide indemnity sufficient in the reasonable judgment of theIssuer to protect the Issuer from any loss which they may suffer if a lost,stolen or destroyed Note is replaced.

# Covenants Bind Successorsand Assigns.  All thecovenants, stipulations, promises and agreements in this Note contained by oron behalf of the Issuer shall bind its successors and assigns, whether soexpressed or not.

# Notices.  All notices, demands and other communicationsprovided for or permitted hereunder shall be made in writing and shall be byregistered or certified first-class mail, return receipt requested,telecopier (with receipt confirmed), courier service or personal delivery atthe addresses set forth in the Company’s records.  All such notices and communications shall bedeemed to have been duly given when: delivered by hand, if personallydelivered; when delivered by courier, if delivered by commercial overnightcourier service; if mailed, ten Business Days after being deposited in themail, postage prepaid; or if telecopied, when receipt is acknowledged.

# Amendment.  Amendments and modifications of the Notes maybe made only pursuant to a writing signed by the Issuer and holders of Notesrepresenting a majority of the aggregate outstanding principal represented bythe Notes at the time of such amendment or modification.

# GOVERNING LAW.  THIS AGREEMENT SHALL BE GOVERNED BY,CONSTRUED IN ACCORDANCE WITH, AND ENFORCED UNDER, THE LAW OF THE STATE OF NEWYORK APPLICABLE TO AGREEMENTS OR INSTRUMENTS ENTERED INTO AND PERFORMEDENTIRELY WITHIN SUCH STATE.

# Severability.  If any one or more of the provisionscontained herein, or the application thereof in any circumstance, is heldinvalid, illegal or unenforceable in any respect for any reason, the validity,legality and enforceability of any such provision in every other respect and ofthe remaining provisions hereof shall not be in any way impaired, unless theprovisions held invalid, illegal or unenforceable shall substantially impairthe benefits of the remaining provisions hereof.

# Headings.  The headings in this Note are for convenienceof reference only and shall not limit or otherwise affect the meaning hereof.

# Definitions.

|   | 20 |   |
|--------|----|--------|

 

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**CONFIDENTIALTREATMENT REQUESTED**

“**Acquisition**” means the acquisition ofSirona Dental Systems Beteiligungs- und Verwaltungs GmbH by the Investors.

“**Business Day**” means a day (other than aSaturday or Sunday) on which banks are open for general business in London andFrankfurt am Main, and:

(a)                                  (in relation to any date for payment orpurchase of a currency other than euro) the principal financial centre of thecountry of that currency; or

(b)                                 (in relation to any date for payment orpurchase of euro) any TARGET Day.

“**Change of Control**” means:

(a)                                  if none of the shares of Sirona Holdings LuxCoSCA or any of its subsidiaries are the subject of a Flotation, (A) theInvestors ceasing to hold at least 50.1% of the voting shares or voting controlin or otherwise control in the Issuer or (B) Madison Dearborn Partners andfunds managed and advised by Madison Dearborn Partners (taken together) ceasingto hold more voting shares or voting control in or otherwise control in theIssuer than any other Initial Investor; or

(b)                                 if any of the shares of Sirona Holdings LuxCoSCA or any of its subsidiaries are the subject of a Flotation, (A) one or moreof the Investors (taken together) ceasing to hold at least 30.1% of the votingshares or voting control in or otherwise control in the Issuer, (B) MadisonDearborn Partners owning less than a majority of such 30.1% of such votingshares or control or (C) any other person or persons acting in concert owning30.1% or more of the voting shares or voting control in or otherwise control ofthe Issuer;

For the purposes of the definition of “**Change of Control**”, “**control**” means, in relation to the Issueror any other person:

(a)                                  the power (whether by way of ownership ofshares, proxy, contract, agency or otherwise) to:

(i)                                     cast,or control the casting of, more than one-half of the maximum number of votesthat might be cast at a general meeting of the Issuer or such other person (asthe case may be); or

(ii)                                  appointor remove all, or the majority, of the directors or other equivalent officersof the Issuer or such other person (as the case may be); or

(iii)                               givedirections with respect to the operating and financial policies of the Issueror such other person (as the case may be) which the directors or otherequivalent officers of the Issuer or such other person (as the case may be) areobliged to comply with; or

(b)                                 the holding of more than one-half of the issuedshare capital of the Issuer or such other person (as the case may be)(excluding any part of that issued share capital that carries no right toparticipate beyond a specified amount in a distribution of either profits orcapital).
|   | 21 |   |
|--------|----|--------|

 

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**CONFIDENTIALTREATMENT REQUESTED**

For the purposesof the definition of “**Change of Control**”,“**acting in concert**” means, a groupof persons who, pursuant to an agreement or understanding (whether formal orinformal), actively co-operate, through the acquisition of shares in the Issuerby any of them, either directly or indirectly, to obtain or consolidate controlof the Issuer.

“**Default**” means an Event of Default or any event orcircumstance which would (with the expiry of a grace period or the giving ofnotice or any combination of the foregoing) be an Event of Default.

“**Financial Indebtedness**” means any indebtedness for or inrespect of:

(a)                                  monies borrowed or raised;

(b)                                 any amount raised by acceptance under anyacceptance credit facility or by a bill discounting or factoring creditfacility;

(c)                                  any amount raised pursuant to any note purchasefacility or the issue of bonds, notes (other than credit notes issued in theordinary course of trade), debentures, loan stock or any similar instrument;

(d)                                 the amount of any liability in respect of anylease or hire purchase contract or other agreement which would, in accordancewith the Accounting Principles, be treated as a finance or capital lease;

(e)                                  receivables sold or discounted (other than anyreceivables to the extent they are sold on a non-recourse basis);

(f)                                    any derivative transaction entered into inconnection with protection against or benefit from fluctuation in any rate orprice (and, when calculating the value of any derivative transaction, only themarked to market value shall be taken into account);

(g)                                 any counter-indemnity obligation inrespect of a guarantee, indemnity, bond, standby or documentary letter ofcredit or any other instrument issued by a bank or financial institution;

(h)                                 any amount raised by the issue of shares whichare redeemable on or before the last Termination Date and the termination dateunder the Mezzanine Facility;

(i)                                     any amount of any liability under an advance ordeferred purchase agreement if (i) one of the primary reasons behind the entryinto the agreement is to raise finance or (ii) the agreement is in respect ofthe supply of assets or services and payment is due more than 180 days from thedate on which the goods were delivered or services were performed;

(j)                                     any amount raised under any other transaction(including any forward sale or purchase agreement) required to be accounted foras a borrowing in accordance with the Accounting Principles; and

(k)                                  (without double counting) the amount of anyliability in respect of any guarantee or indemnity or similar assurance againstfinancial loss for any of the items 
|   | 22 |   |
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**CONFIDENTIALTREATMENT REQUESTED**

referred to in the preceding paragraphs of thisdefinition and any agreement to maintain the solvency of any person whether byinvesting in, lending to or purchasing the assets of such person.

“**Flotation**” means the listing of any shareson any stock exchange or the grant of permission to deal in any such shares onany recognised exchange.

“**Group**” means Sirona Luxco Holdings CSA andits subsidiaries for the time being.

“**Investors**” means funds managed and advisedby Madison Dearborn Partners and other investors selected by Madison DearbornPartners as part of the equity (and quasi-equity) syndication of the equity andquasi-equity funding for the Acquisition (subject to Madison Dearborn Partnersat all times owning a majority interest in, and being able to direct theaffairs and control the composition of the board of directors or equivalentbody of, such investors), and each of their or any subsequent successors orpermitted assignees or transferees.

**“Senior and Mezzanine**Loan Agreements” means: the senior and mezzanine facilitiesagreements dated 29 April 2005 between, inter alios, JP Morgan PLC, JPMorganChase Bank NA, JP Morgan Europe Ltd and Blitz F04-506, as the same may beamended, restated, refinanced, supplemented or otherwise modified from time totime.

“**US LIBOR**” means: with respect to anycalendar quarter, the rate of interest per annum (rounded to the nearest 1/16of 1%) specified as the three month London Interbank Offered Rate (LIBOR) inThe Wall Street Journal on the first business day immediately preceding thefirst day of such calendar quarter.

INWITNESS WHEREOF, this Subordinated Promissory Note is executed and delivered asof the date first set forth above.

[SIRONA HOLDINGS LUXCO SCA]

By: 

___________________________________

Name:Title:

 

 

 

 

**[SIGNATURE PAGE TO SUBORDINATED PROMISSORY NOTE]**

 
|   | 23 |   |
|--------|----|--------|

 

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**CONFIDENTIALTREATMENT REQUESTED [*] designates portions of this documentthat have been omitted pursuant to a request forconfidential treatment filed separately with the Securities and ExchangeCommission.**

**Annex 3 to Distributorship Agreement**

**Prices of Contractual Products**

**ineffect as of June 30, 2005**
| ** ** | Product                                                                                                                                                                                                                                                                             | ** ** | **Order  Number**        | ** ** | **Patterson  Price in US  Dollars** | ** ** |
|------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------|--------------------------|------------|-------------------------------------|------------|
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
| ** ** | **CEREC 3, complete**                                                                                                                                                                                                                                                               | ** ** | **5811000**              | ** ** | **$**                               | ** ** |
|       | consists of                                                                                                                                                                                                                                                                         | ** ** | ** **               | ** ** | ** **                          | ** ** |
|       | imaging unit (without  3D software)                                                                                                                                                                                                                                                 | ** ** | **5851055**              | ** ** | **$****[*]**                        | ** ** |
|       | milling unit (including  3D software)                                                                                                                                                                                                                                               | ** ** | **5833400**              | ** ** | **$****[*]**                        | ** ** |
|       | wireless connection                                                                                                                                                                                                                                                                 | ** ** | **5855882**              | ** ** | **$****[*]**                        | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
| ** ** | **inLab**                                                                                                                                                                                                                                                                           | ** ** | **5884742**              | ** ** | **$****[*]**                        | ** ** |
| ** ** | **AK’s (dongles)**                                                                                                                                                                                                                                                             | ** ** | ** **               | ** ** | ** **                          | ** ** |
|       | AK 100                                                                                                                                                                                                                                                                              |       | **5900563**              | ** ** | **$****[*]**                        | ** ** |
|       | AK 200                                                                                                                                                                                                                                                                              |       | **5900571**              | ** ** | **$****[*]**                        | ** ** |
|       | AK 500                                                                                                                                                                                                                                                                              |       | **5900589**              | ** ** | **$****[*]**                        | ** ** |
|       | AK 1000                                                                                                                                                                                                                                                                             |       | **5900597**              | ** ** | **$****[*]**                        | ** ** |
|       | AK 2000                                                                                                                                                                                                                                                                             |       | **5900605**              | ** ** | **$****[*]**                        | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
| ** ** | **inEos Scanner, introduction offer   through June 30th, 2005**                                                                                                                                                                                                                     | ** ** | **6005909**              | ** ** | **$****[*]**                        | ** ** |
| ** ** | ** **                                                                                                                                                                                                                                                                          | ** ** | ** **               | ** ** | ** **                          | ** ** |
| ** ** | **inEos Scanner, regular price   starting July 1st, 2005**                                                                                                                                                                                                                          | ** ** | **6005909**              | ** ** | **$****[*]**                        | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
| ** ** | **Package Scanner+inLab**                                                                                                                                                                                                                                                           | ** ** | **6005909  and 5884742** | ** ** | **$****[*]**                        | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |
| ** ** | **Spare part and consumable prices will be set  based on the Sirona’s current suggested resale spare part price list, less a  [*]% discount to Patterson, unless exceptions are mutually agreed between  Sirona and Patterson (e.g., special pricing for CEREC Club members)** |
|       |                                                                                                                                                                                                                                                                                | ** ** | ** **               | ** ** | ** **                          | ** ** |

 

 

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