The American Board of Orthodontics
Grading System for Dental
Casts and Panoramic Radiographs

Revised June 2012
© The American Board of Orthodontics

Grading System for Dental Casts and Panoramic Radiographs

TABLE OF CONTENTS
3

INTRODUCTION

3BACKGROUND

5

CRITERIA AND RATIONALE................................................................................ Alignment ...... 5...................................................................... Marginal Ridges ...... 5.......................................................... Buccolingual Inclination ...... 5................................................................... Occlusal Contacts ...... 6............................................................. Occlusal Relationship ...... 6.................................................................................... Overjet ...... 6............................................................ Interproximal Contacts ...... 6...................................................................... Root Angulation ...... 6

7

MODEL ANALYSIS................................................................................ Alignment ...... 7...................................................................... Marginal Ridges ...... 9.......................................................... Buccolingual Inclination .... 10................................................................... Occlusal Contacts .... 11............................................................. Occlusal Relationship .... 13.................................................................................... Overjet .... 14............................................................ Interproximal Contacts .... 16

17
19

RADIOGRAPHIC ANALYSIS...................................................................... Root Angulation .... 17
EVALUATION OF CASES

19

SUMMARY20

ABO MEASURING GAUGE21

REFERENCES

22

MAJOR UPDATES-2-MODEL GRADING SYSTEMINTRODUCTION
The American Board of Orthodontics is constantly striving to make the clinicalexamination a fair, accurate, and meaningful experience for examinees. In an effort toenhance the reliability of the examiners and provide the examinees with a tool to assess
the adequacy of their finished orthodontic results, the Board has established a Model
Grading System to evaluate the final dental casts and panoramic radiographs. This
scoring system was developed systematically through a series of four field tests over a
period of five years. The Board instituted the model and radiographic portions of theModel Grading System, and it has been used to grade these portions of the examinees’
clinical case reports since 1999. In an effort to assist examinees with the selection of
their cases, the Board is making this Model Grading System available to all examinees.
The Board encourages examinees to score their own case reports with this scoring
system to determine if they meet Board standards.

BACKGROUND
In 1994, The American Board of Orthodontics began investigating methods of making
the clinical examination more objective. Since a major emphasis has always beenplaced on the final occlusion, the first efforts were directed at developing an objective
method of evaluating the dental casts and intraoral radiographs.
In the past, several indices have been used to evaluate the outcome of orthodontic
treatment.1,2,3,4 Generally, these indices compare pretreatment and posttreatment
records to determine the quality of the final result. However, these indices are notprecise, and the validity and reliability of these indices has not been established. The
Occlusal Index5 has also been used to determine treatment quality. However, thismethod is tedious, and the system is more appropriate for scoring pretreatment rather
than posttreatment records.
In 1987, the PAR Index6 (Peer Assessment Rating) was developed to assess an
occlusion at any stage of development. Over 200 dental casts representing various
pretreatment and posttreatment stages of occlusion were used to establish this index.
The PAR Index has good reliability and validity, however this measuring system is notprecise enough to discriminate between the minor inadequacies of tooth position thatare found in ABO case reports. Therefore, an ABO committee was formed in 1994, tobegin field testing precise methods of objectively evaluating posttreatment dental casts
and panoramic radiographs.

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MODEL GRADING SYSTEMAt the 1995 ABO clinical examination, 100 cases were evaluated. A series of 15 criteria
were measured on each of the final dental casts and panoramic radiographs. The data
showed that 85% of the inadequacies in the final results occurred in seven of the 15
criteria (alignment, marginal ridges, buccolingual inclination, overjet, occlusal
relationships, occlusal contacts, root angulation).
Therefore, at the 1996 clinical examination, a second field-test was initiated to verify the
results of the previous test and to determine if multiple examiners could score therecords reliably and consistently. In this field test, a subcommittee of four Directors
evaluated 300 sets of post-treatment dental casts and panoramic radiographs. Again,
the majority of the inadequacies in the final results occurred in the same sevencategories, but the committee had difficulty establishing adequate inter-examiner
reliability. The subcommittee recommended that a measuring instrument be developed
to make the measuring process more reliable.
In 1997, a third field test was performed using the modified scoring system with theaddition of an instrument to measure the various criteria more accurately. All of the
Directors participated in this field test, and a total of 832 dental casts and panoramic
radiographs were measured. The same seven criteria were evaluated. A calibration
session preceded the examination to establish more accurate use of the measuring
instrument and improve the reliability of the Directors. The results again showed thatthe overwhelming majority of the inadequacies in the finished results occurred in the
aforementioned categories. However, the Directors decided to add interproximal
contacts to the scoring system to raise the total number of criteria to eight. In addition,
modifications were made in the measuring instrument to improve measuring accuracy
among Directors.
In 1998, the fourth and final field test was initiated. Again all Directors participated in
the evaluation process. The new and improved measuring instrument was used. An
extensive training and calibration session was performed prior to the actual
examination. The major objectives of this final field test were to refine the measuring
and calibration process, and to gather enough data on general performance to establish
the validity or cut-off for passing this portion of the clinical examination. This field test
was extremely successful. Not only did it reaffirm the benefits of using an objective
system for grading the dental casts and panoramic radiographs, but also it helped toestablish standards for successful completion of this portion of the clinical examination.
Based upon the collective and cumulative results of these extensive field tests, theBoard decided to officially initiate the use of this Model Grading System for examinees
at the February 1999, ABO clinical examination in St. Louis. In order to assist theexaminee in selecting cases that will successfully pass the examination process, theBoard is providing the examinee with the same system used by the Directors. The
Board encourages examinees to score their own dental casts and panoramic
radiographs during their preparation for the clinical examination in order to select casesthat will successfully pass the ABO Model Grading System.

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MODEL GRADING SYSTEMCRITERIA AND RATIONALE
The ABO Model Grading System for scoring dental casts and panoramic radiographs
contains eight criteria. These are: alignment, marginal ridges, buccolingual inclination,
occlusal relationships, occlusal contacts, overjet, interproximal contacts, and root
angulation. The rationale for using these criteria is stated in the following section.
Alignment is usually a fundamental objective of any orthodontic treatment plan.
Therefore, it seems reasonable that any assessment of quality of orthodontic resultmust contain an assessment of tooth alignment. In the anterior region, the incisal edges
and lingual surfaces of the maxillary anterior teeth and the incisal edges and labialincisal surfaces of the mandibular anterior teeth were chosen as the guide to assess
anterior alignment. These are not only the functioning areas of these teeth, but theyalso influence esthetics if they are not arranged in proper relationship. In the maxillaryposterior region, the mesiodistal central groove of the premolars and molars is used toassess adequacy of alignment. In the mandibular arch, the buccal cusps of the
premolars and molars are used to assess proper alignment. These areas were chosen
since they represent easily identifiable points on the teeth, and represent the functioning
areas of the posterior teeth. The results of the four field tests show that the mostcommonly malaligned teeth were the maxillary and mandibular lateral incisors andsecond molars, which accounted for nearly 80% of the mistakes.
Marginal ridges are used to assess proper vertical positioning of the posterior teeth. In
patients with no restorations, minimal attrition, and no periodontal bone loss, themarginal ridges of adjacent teeth should be at the same level. If the marginal ridges areat the same relative height, the cementoenamel junctions will be at the same level. In aperiodontally healthy individual, this will result in flat bone level between adjacent teeth.
In addition, if marginal ridges are at the same height, it will be easier to establish properocclusal contacts, since some marginal ridges provide contact areas for opposing
cusps. Based upon the four field tests, the most common mistakes in marginal ridgealignment occurred between the maxillary first and second molars. The second mostcommon problem area was between the mandibular first and second molars.
Buccolingual inclination is used to assess the buccolingual angulation of the posterior
teeth. In order to establish proper occlusion in maximum intercuspation and avoid
balancing interferences, there should not be a significant difference between the heightsof the buccal and lingual cusps of the maxillary and mandibular molars and premolars.
The Directors use a special step gauge to assess this relationship. Some latitude isallowed, however in past field tests significant problems were observed in the
buccolingual inclination of the maxillary and mandibular second molars.

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MODEL GRADING SYSTEM
Occlusal contacts are measured to assess the adequacy of the posterior occlusion.
Again, a major objective of orthodontic treatment is to establish maximum intercuspationof opposing teeth. Therefore, the functioning cusps are used to assess the adequacy ofthis criterion; i.e., the buccal cusps of the mandibular molars and premolars, and the
lingual cusps of the maxillary molars and premolars. If cusp form is small or diminutive,that cusp is not scored. In past field tests, the most common problem area has been
inadequate contact between maxillary and mandibular second molars.
Occlusal relationship is used to assess the relative anteroposterior position of themaxillary and mandibular posterior teeth. In order to achieve accuracy and reliability inmeasuring this relationship, results of previous field tests have shown that the mostverifiable method of scoring this criterion is to use Angle’s relationship. Therefore, thebuccal cusps of the maxillary molars, premolars, and canines must align within 1 mm ofthe interproximal embrasures of the mandibular posterior teeth. The mesiobuccal cuspof the maxillary first molar must align within 1 mm of the buccal groove of themandibular first molar.
Overjet is used to assess the relative transverse relationship of the posterior teeth, andthe anteroposterior relationship of the anterior teeth. In the posterior region, themandibular buccal cusps and maxillary lingual cusps are used to determine proper
position within the fossae of the opposing arch. In the anterior region, the mandibular
incisal edges should be in contact with the lingual surfaces of the maxillary anterior
teeth. In past field tests, the common mistakes in overjet have occurred between the
maxillary and mandibular incisors and second molars.
Interproximal contacts are used to determine if all spaces within the dental arch havebeen closed. Persistent spaces between teeth after orthodontic therapy are not only
unesthetic, but can lead to food impaction. In past field tests, spacing is generally not amajor problem with ABO cases.
Root angulation is used to assess how well the roots of the teeth have been positioned
relative to one another. Other than periapical radiographs or three-dimensional
imaging, the panoramic radiograph is probably the best practical means for making thisassessment. It is incumbent upon the examinee to present imaging evidence todocument posttreatment root position. If roots are properly angulated, then sufficientbone will be present between adjacent roots, which could be important if the patientwere susceptible to periodontal bone loss at some point in time. If roots are dilacerated,then they are not graded. In past field tests, the common mistakes in root angulation
occurred in the maxillary lateral incisors, canines, second premolars, and mandibular
first premolars.

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MODEL GRADING SYSTEMGUIDE FOR GRADING CLINICAL CASE REPORTS
MODEL ANALYSISALIGNMENTIn the maxillary and mandibular anterior regions, proper alignment is characterized bycoordination of alignment of the incisal edges and lingual incisal surfaces of themaxillary incisors and canines (fig. 1), and the incisal edges and labial incisal surfacesof the mandibular incisors and canines (fig. 2).

figure 1

figure 2

In the mandibular posterior quadrants, the mesiobuccal and distobuccal cusps of themolars and premolars should be in the same mesiodistal alignment. In the maxillaryarch, the central grooves (mesio-distal) should all be in the same plane or alignment(fig. 3). If all teeth are in alignment, or within 0.50 mm of proper alignment, no points
are scored.

figure 3-7-

MODEL GRADING SYSTEM
If the mesial or distal alignment at any of the contact points is 0.50 mm to 1 mm
deviated from proper alignment (fig. 4a,b), 1 point shall be scored for the tooth that isout of alignment. If adjacent teeth are out of alignment, then 1 point should be scoredfor each tooth.

figure 4a

figure 4b

If the discrepancy in alignment of a tooth at the contact point is greater than 1 mm, then
2 points shall be scored for that tooth (fig. 5a,b). No more than 2 points shall be scoredfor any tooth.

figure 5a

figure 5b-8-

MODEL GRADING SYSTEMMARGINAL RIDGES
In both maxillary and mandibular arches, marginal ridges of adjacent posterior teeth
shall be at the same level, or within 0.50 mm of the same level (fig. 6).

figure 6
In scoring, do not include the canine-premolar contact; and do not include the distal oflower 1st premolar.
If adjacent marginal ridges deviate from 0.50 to 1 mm (fig. 7), then 1 point is scored forthat interproximal contact. If the marginal ridge discrepancy is greater than 1 mm (fig.
8), then 2 points shall be scored for that interproximal contact. No more than 2 points
will be scored for any contact point. The marginal ridge will be considered as the mostocclusal point that is within 1 mm of the contact at the occlusal surface of adjacent
teeth.

figure 7

figure 8-9-MODEL GRADING SYSTEMBUCCOLINGUAL INCLINATIONThe buccolingual inclination of the maxillary and mandibular posterior teeth shall beassessed by using a flat surface that is extended between the occlusal surfaces of theright and left posterior teeth. When positioned in this manner, the straight edge should
contact the buccal cusps of contralateral mandibular molars and premolars. The lingual
cusps should be within 1 mm of the surface of the straight edge (fig. 9). In the maxillaryarch, the straight edge should contact the lingual cusps of the maxillary molars andpremolars. The buccal cusps should be within 1 mm of the surface of the straight edge
(fig. 10).

figure 9

figure 10

Do not score the mandibular 1st premolars nor the distal cusps of the second molars.
If the mandibular lingual cusps or maxillary buccal cusps are more than 1 mm, but lessthan 2 mm from the straight edge surface (fig. 11a,b), 1 point shall be scored for that
tooth.

figure 11a

figure 11b- 10 -

MODEL GRADING SYSTEM

figure 12a

figure 12b

If the discrepancy is greater than 2 mm (fig. 12a,b), then 2 points are scored for that
tooth. No more than 2 points shall be scored for any tooth.

OCCLUSAL CONTACTS
This section of the evaluation determines the adequacy of occlusal contact of the
premolars and molars. The buccal cusps of the mandibular premolars and molars (fig.
13) and the lingual cusps of the maxillary premolars and molars (fig. 14) should becontacting the occlusal surfaces of the opposing teeth. Each mandibular premolar has
one functional cusp. Each mandibular molar has two functional buccal cusps. The
maxillary premolars have one functional lingual cusp. However, the maxillary molars
may have only a mesiolingual functional cusp.

figure 13

figure 14- 11 -

MODEL GRADING SYSTEM
If the distolingual cusp is short or diminutive (fig. 15), it should not be considered in theevaluation. If this cusp is prominent, but does not contact with the opposing arch, thenpoints may be scored. If the cusps are in contact with the opposing arch, no points arescored. Do not score diminutive distolingual cusps of the maxillary 1st and 2nd molars,
nor lingual cusps of the mandibular first premolars.

figure 15
If a cusp is out of contact with the opposing arch, and the distance is 1 mm or less (fig.
16), then 1 point is scored for that tooth. If the cusp is out of contact and the distance isgreater than 1 mm (fig. 17), then 2 points are scored for that tooth. No more than 2points are scored for each tooth.

figure 16

figure 17- 12 -

MODEL GRADING SYSTEMOCCLUSAL RELATIONSHIP
This section of the evaluation determines whether the occlusion has been finished in
an Angle Class I relationship. Ideally, the maxillary canine cusp tip should align with (orwithin 1 mm of) the embrasure or contact between the mandibular canine and adjacentpremolar (fig. 18). The buccal cusps of the maxillary premolars should align with (or bewithin 1 mm of) the embrasures or contacts between the mandibular premolars and firstmolar (fig. 18). The mesiobuccal cusps of the maxillary molars should align with (or bewithin 1 mm of) the buccal grooves of the mandibular molars (fig. 18).

figure 18

If the maxillary buccal cusps deviate between 1 and 2 mm from the aforementioned
positions (fig. 19), then 1 point shall be scored for that maxillary tooth. If the buccal
cusps of the maxillary premolars or molars deviate by more than 2 mm from ideal
position (fig. 20), then 2 points shall be scored for each maxillary tooth that deviates.
No more than 2 points shall be scored for each maxillary tooth. In some situations, theposterior occlusion may be finished in either an Angle Class II or Class III relationship,depending upon the type of tooth extraction in the maxillary or mandibular arches.

figure 19

figure 20- 13 -

MODEL GRADING SYSTEM
In a Class II situation (fig. 21), the buccal cusp of the maxillary first molar should alignwith the embrasure or interproximal contact between the mandibular second premolar
and first molar. The buccal cusp of the maxillary second molar should align with theembrasure or interproximal contact between the mandibular first and second molars. If
the final occlusion is finished in a Class III relationship (when mandibular premolars are
extracted), the buccal cusp of the maxillary second premolar should align with the
buccal groove of the mandibular first molar (fig. 22). The remaining occlusion distal tothe maxillary second premolar and mandibular first molar are adjusted accordingly.

figure 21

figure 22

OVERJETThe overjet is evaluated by articulating the models and viewing the labiolingual
relationship of the maxillary arch relative to the mandibular arch. In order to determine
the proper relationship of the casts, the examiner must rely on the trimming of the backsof the bases of the models. The models are set flat on their backs, in order todetermine this assessment (fig. 23).

figure 23- 14 -

MODEL GRADING SYSTEM
If the models are mounted on an articulator, then the articulated mounting shalldetermine the proper maxillary and mandibular model relationship. If the proper overjet
has been established, then the buccal cusps of the mandibular molars and premolars
will contact in the center of the occlusal surfaces, buccolingually, of the maxillary
premolars and molars (fig. 24). In the anterior region, the mandibular canines andincisors will contact the lingual surfaces of the maxillary canines and incisors (fig. 25). If
this relationship exists, no points are scored.

figure 24

figure 25

If the mandibular buccal cusps deviate 1 mm or less from the center of the opposing
tooth (fig. 26), 1 point is scored for that tooth. If the position of the mandibular buccal
cusps deviates more than 1 mm from the center of the opposing tooth (fig. 27), twopoints are scored for that tooth. No more than 2 points are scored for any tooth.

figure 26

figure 27- 15 -

MODEL GRADING SYSTEM
In the anterior region, if the mandibular canines or incisors are not contacting lingualsurfaces of the maxillary canines and incisors, and the distance is 1 mm or less (fig. 28),
then 1 point is scored for each maxillary tooth. If the discrepancy is greater than 1 mm
(fig. 29), then 2 points are scored for each maxillary tooth.

figure 28

figure 29

Note that although Overjet is typically scored by assessing contact between opposing
teeth, this score is subject to examiner modification. For example, cases in which
incisors display extremely acute inter-incisal angles and/or significant overlap of incisaledges may be scored an additional point.

INTERPROXIMAL CONTACTS
This assessment is made by viewing the maxillary and mandibular dental casts from an
occlusal perspective. The mesial and distal surfaces of the teeth should be in contact
with one another (fig. 30). If 0.50 mm or less interproximal space exists, then no points
are scored.

figure 30- 16 -

MODEL GRADING SYSTEM
If greater than 0.50 to 1 mm of interproximal space exists between two adjacent teeth(fig. 31), then 1 point is scored for that interproximal contact. If more than 1 mm ofspace is present between two teeth (fig. 32), then 2 points are scored for thatinterproximal contact. No more than 2 points are scored for any contact that deviatesfrom ideal.

figure 31

figure 32

RADIOGRAPHIC ANALYSISROOT ANGULATIONThe relative angulation of the roots of the maxillary and mandibular teeth is assessed on
the panoramic radiograph. Although this is not ideal, it gives a reasonably good
assessment of root position. Generally, the roots of the maxillary and mandibular teeth
should be parallel to one another and oriented perpendicular to the occlusal plane (fig.
33). If this situation exists, then no points are scored.

figure 33- 17 -

MODEL GRADING SYSTEM
The ABO acknowledges the distortion that frequently occurs within panoramic
radiographs. The Board has recommended the following:
Omit scoring the canine relationship with adjacent tooth rootwhen using a final panoramic radiograph.
If a root is angled to the mesial or distal (not parallel) and is close to, but not touching,
the adjacent tooth root, then 1 point is scored for each discrepancy (anterior, premolar,
and/or molar areas, fig. 34). If the root is angled to the mesial or distal and is contacting
the adjacent tooth root (fig. 35), then 2 points are scored for that tooth.

figure 34

figure 35- 18 -

MODEL GRADING SYSTEMEVALUATION OF CASESThe Board’s decision to evaluate an individual case as Complete or Incomplete is based
upon multiple factors. Record quality and the ability to finish a case are important, butthey are not the only aspects that are considered in the evaluation. Case management,a sound understanding of diagnosis, treatment planning and mechanotherapy are
equally important and are discussed during the actual interview when cases arereviewed with the examinee.
A score corresponding to Complete in the Cast-Radiograph Evaluation and CaseManagement are determined at every clinical examination during a pre-exam calibration
session of all examiners. Therefore, scores for cases evaluated as Complete will varyfrom exam to exam and may range from:

27 or less for C-R Eval
7 or less for CMF
And, case meets DI and case criteriaHigh scores on individual segments, or combinations of individual segments, may causea case to become Incomplete. From time to time, however, a successful interview may
result in an overturn of an otherwise Incomplete case.

SUMMARY
The Directors of The American Board of Orthodontics have spent countless hours
developing this system for assessing the occlusal and radiographic results oforthodontic treatment. The usefulness of this system depends not only on its objectivity,
but more importantly on the validity and reliability of the measurements. After repeatedcomparison of both objective and subjective systems, the Directors are confident thatthe “cut-off” score to pass this portion of the clinical examination is valid. Reliability will
be insured through the use of a precise measuring instrument, in addition to training andcalibration of the Directors before each examination. In order to be fair to all
examinees, a confidence interval is established to account for interrater variability.
Although the underlying purpose of establishing this grading system is to insure reliable,
objective evaluation of orthodontic records, the Board sees a much greater benefit topublishing this grading system. Now, examinees may grade their own results before theclinical examination and know if their results will pass Board standards. Furthermore,
Diplomates may use this scoring system at anytime in their clinical career to determine
if they are producing “Board quality” results. The Board hopes that this method of selfevaluation will help to elevate the overall quality of orthodontic care.

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MODEL GRADING SYSTEMABO MEASURING GAUGEAThis portion of the gauge is in 1 mm increments and is used to measurediscrepancies in alignment, overjet, occlusal contact, interproximal contact, andocclusal relationships. The width of the gauge is 0.5 mm.

B

This portion of the gauge has steps measuring 1 mm in height and is used todetermine discrepancies in mandibular posterior buccolingual inclination.

C

This portion of the gauge has steps measuring 1 mm in height and is used todetermine discrepancies in marginal ridges.

DThis portion of the gauge has steps measuring 1 mm in height and is used todetermine discrepancies in maxillary posterior buccolingual inclination.

NOTE: Third molars are not scored unless they substitute for the second molars.

You may download the ABO Grading System for Casts-Radiographs fromthe ABO website > Orthodontic Professionals > Clinical Examination >Download and Print: Forms and References.
This gauge is included in the Calibration Kit along with three sets of premeasured cases. There is a digital component to the Calibration Kit which
arrives as an attachment to the email receipt of purchase. The digitalcomponent contains the grading system manual, panoramic radiographs
and scoring keys.

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MODEL GRADING SYSTEMREFERENCES
1.

Eismann, D A method of evaluating efficiency of orthodontic treatment, Trans Europ
Orthod Soc, 223-232, 1974

2.

Eismann, D Reliable assessment of morphological changes resulting from orthodontic
treatment, Europ J Orthod, 2:19-25, 1980

3.

Gottlieb, E Grading your orthodontic treatment results, J Clin Orthod, 9:156-161, 1975

4.

Berg, R Post-retention analysis of treatment problems and failures in 264 consecutively
treated cases, Europ J Orthod, 1:55-68, 1979

5.

Summers, C The occlusal index: a system for identifying and scoring occlusal
disorders, Am J Orthod, 59:552-566, 1971

6.

Richmond, S., Shaw, W, et al. The development of the PAR Index (Peer Assessment
Rating): reliability and validity, Europ J Orthod, 14:125-139, 1992

7.

Mckee, I., Williamson, C., et al. The accuracy of 4 panoramic units in the projection ofmesiodistal tooth angulations, AJO-DO 2002, 121:166-175

8.

Peck, J., Sameshima, G., et al. Mesiodistal Root Angulation Using Panoramic andCone Beam CT, Angle Orthodontist 2007, No. 2:206-213

9.

Owens, A. M., Johal, A. Near End of Treatment Panoramic Radiograph in theAssessment of Mesiodistal Root Angulation, Angle Orthodontists, Vol 78, No.3:475-481- 21 -

MODEL GRADING SYSTEM
MAJOR UPDATES
Pre-2006

Marginal Ridges – In scoring, do not include the canine-premolar contact; and do notinclude the distal of lower 1st premolar.
Occlusal Contacts - Do not score diminutive distolingual cusps of the maxillary 1st and2nd molars, nor lingual cusps of the maxillary first premolars.

2006

Language update - revise historical discussions; change “candidate” to “examinee”;
change “Phase III” to “Clinical”.
Root Angulation - Other than periapical radiographs or three-dimensional imaging,
the panoramic radiograph is probably the best practical means for making thisassessment. It is incumbent upon the examinee to present imaging evidence todocument posttreatment root position.

2007

Points will be scored in absolute value; therefore, change “deduct points” to“score points”.
Language update - change “Objective Grading System” to “Model Grading System”.
References – Addition of McKee; Peck, Owens articles.

June 2008

Occlusal Contacts – If cusp is out of contact, score for each posterior tooth; no more than
2 points per tooth.
Root Angulation – Omit scoring the canine relationship with adjacent root; newexamples for Figures 34 and 35.

June 2010

Buccolingual Inclination –When positioned in this manner, the straight edge should contact the buccal cusps ofcontralateral mandibular molars and premolars.
Do not score the mandibular 1st premolars nor the distal cusps of the second molars.

March 2011

Overjet – Note that although Overjet is typically scored by assessing contact between
opposing teeth, this score is subject to examiner modification. For example, cases inwhich incisors display extremely acute inter-incisal angles and/or significant overlap ofincisal edges may be scored an additional point.

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