bluuebunny/crossref_metadata_2025 huggingface dataset:
Immediate Occlusal Loading of Brånemark TiUnite™ Implants Placed Predominantly in Soft Bone: 1‐Year Results of a Prospective Clinical Study
Authors: Glauser Roland , Lundgren AnnaKarin , Gottlow Jan , Sennerby Lars , Portmann Michael , Ruhstaller Petra , Hämmerle Christoph H.F.
Published: October 2006

Background:

The original Brånemark protocol for dental implant treatment was based on submerged healing prior to loading. However, immediate loading has been reported possible with high success rates for various indications, provided that good bone quality and quantity are present. In many of these studies, machined‐surface implants have been used. Recently, a new surface texture has been developed, based on an oxidation processing, that aims to enhance the early bone response (Brånemark System® Mk IV TiUnite™, Nobel Biocare AB, Gothenburg, Sweden). It has been documented that this surface texture may help to better maintain primary implant stability during the early healing period and that secondary implant stability can be reached earlier compared with results when using a machined surface. Such a positive influence on implant stability might be an advantage when applying an immediate‐loading protocol, especially in soft bone regions where a tendency toward reduced success rates has been reported.

Purpose:

The aim of this report was to present the short‐term success rates of TiUnite‐surfaced immediate occlusally loaded Brånemark System Mk IV implants placed in various regions of the jaws.

Materials and Methods:

Thirty‐eight patients received a total of 51 prosthetic reconstructions, all of which were connected on the day the implants were inserted. Of these, 20 were single‐tooth restorations, 30 were fixed partial dentures, and 1 was a complete fixed lower jaw restoration. These prostheses were supported by 102 Brånemark System Mk IV TiUnite implants (38 maxillary and 64 mandibular), the majority of which were placed in posterior regions (88%) and mainly in soft bone (76%). Cutting resistance measurements were performed during implant insertion, and resonance frequency measurements were conducted during the course of the study. Furthermore, radiographic examinations were performed in connection with the delivery of the prostheses and at the 1‐, 6‐, and 12‐month follow‐up visits. This article reports on the results after 1 year of loading.

Results:

Three maxillary implants were removed, although stable, in one patient at the 8‐week follow‐up because of postoperative infection in the adjacent area of guided bone regeneration (GBR). This resulted in a cumulative success rate of the implants of 97.1% after 1 year of prosthetic loading. The mean marginal bone resorption after 1 year of loading was 1.2±0.9 mm (SD).

Conclusions:

The applied immediate loading protocol in combination with a slightly tapered implant and a modified implant surface texture was shown to be a successful treatment alternative even in regions exhibiting soft bone.
Immediate Occlusal Loading of Single Lower Molars Using Brånemark System® Wide‐Platform TiUnite™ Implants: An Interim Report of a Prospective Open‐Ended Clinical Multicenter Study
Authors: Calandriello Roberto , Tomatis Massimiliano , Vallone Roberto , Rangert Bo , Gottlow Jan
Published: October 2006

Background:

First and second molars in the lower jaw are the most commonly missing teeth. As in other jaw regions with tooth loss, implant therapy is an attractive concept. Owing to the wide dimension of the molar teeth, wide implants seem to be a natural choice. However, wide implants in posterior mandibular regions sometimes present a problem. As an oxidized surface seems to facilitate implant integration and to result in a stronger fixation to bone, it was hypothesized that this surface would improve the performance of wide implants in posterior mandibles. As high initial stability most often is achieved in this region, it was hypothesized that the load per se is not a problem.

Purpose:

The purpose of the present study is to evaluate immediate loading of Brånemark System® TiUnite™ Wide‐Platform implants (Nobel Biocare AB, Gothenburg, Sweden) supporting single molar crowns in the lower jaw.

Materials and Methods:

The study includes 44 patients treated in three separate private dental offices between March 2001 and June 2002. A total of 50 implants were placed, and all implants have passed the 6‐month follow‐up; 24 have been followed up for 1 year. All implants were provided with provisional crowns in centric occlusion at the time of surgery.

Results:

No implant has been lost. Marginal bone levels were found in accordance with normal biologic width requirements. Resonance frequency analysis showed high and consistent implant stability. No biomechanical problems were found associated with the use of wide implants, and the potential physiologic problem in dense mandibular bone was eliminated.

Conclusion:

Although limited by being a short‐term study, the result encourages immediate loading of single Brånemark System TiUnite Wide‐Platform implants placed in the molar regions in the lower jaw.
Early Functional Loading in the Fully Edentulous Mandible after Mandibular Resection and Reconstruction due to an Ameloblastoma: Case Report
Authors: Becker William , Wong James
Published: October 2006

Background: Immediate or early functional loading of implants in fully edentulous mandibles can enhance patient comfort and the ability to masticate within a few days after implant placement. Recently there has been evidence that this method of restoring edentulous mandibles is predictable.

Purpose: The goal of this case report is to present the treatment of a patient diagnosed with a large ameloblastoma in the mandible. After removal of the tumor and mandibular reconstruction, the patient had complete anesthesia in the right mandible, with an alveolar ridge deformity.

Methods: Two years after removal of an ameloblastoma in the right mandibluar sextant, five implants were installed between the mental foramina. One implant was installed for safety reasons in the event one of the others was lost. This implant remains buried. A denture was used as a drilling guide. Abutments were attached to the implants, and impression copings were fixed to the abutments. The denture was used for the “pickup” impression. Flaps were sutured, maintaining exposure of the abutments. In the laboratory, gold cylinders were heat cured to the tissue side of the denture. The cylinders were attached to the cast with laboratory screws. The gold cylinders were heat cured to the intaglio side of the denture. Five days after implant placement, the nonmetal reinforced acrylic denture was fixed to the implants with laboratory screws. The bridge is removed annually, and the implants are examined for mobility and periapical radiographs are taken.

Results: The patient has worn the prosthesis for 2.5 years without loss of implants and without breakage of the nonmetal reinforced denture. At 2.5 years the implants are stable, implant sites demonstrate stable crestal bone, and the patient is eating comfortably and without limitations.

Conclusion: Early functional loading of implants in the edentulous mandible may offer patients the option of wearing implant‐supported prosthesis immediately or shortly after implant insertion.
Resorbable and Nonresorbable Hydroxyapatite Granules as Bone Graft Substitutes in Rabbit Cortical Defects
Authors: Liljensten Elisabeth , Adolfsson Erik , Strid Karl‐Gustav , Thomsen Peter
Published: October 2006

Background: The use of various synthetic calcium phosphate compositions for the promotion of bone in bone defects is of potential interest because such materials may be tailor made and may bond to bone. There is yet an inadequate knowledge of the role of calcium phosphate composition and resorbability for the bone response.

Purpose: The aim of the present study was to compare the ability of resorbable versus nonresorbable hydroxyapatite (HA) granules to promote new bone formation in cortical bone defects. Resorbable and nonresorbable HA granules, used as bone graft substitutes, were evaluated after 6 weeks and 3 months in the rabbit tibia. Circular defects (diameter 5.0 mm) were made in both tibias of 18 New Zealand white rabbits. The 36 defects were divided into three groups (six observations per group and time, respectively). The first group was augmented with resorbable HA granules, the second group was augmented with ceramic nonresorbable HA granules, and the third group was left without augmentation (control). The animals were killed after 6 weeks and 3 months, and the tissue was evaluated with light microscopic (LM) morphology and morphometry, scanning electron microscopy (SEM), and energy dispersive x‐ray analysis (EDX).

Results: After 3 months LM morphometry revealed significantly more newly formed bone in the two HA augmented groups compared with that in the control. A close contact was found between both kinds of HA granules and new bone as viewed with light microscopy and SEM. A relatively slow degradation process was indicated by the small reduction of the total granule area in the cortical defects. However, LM observations showed a change of granule form. Pilot experiments using SEM‐EDX indicate that Ca and P contents had decreased in the resorbable HA granules between 6 weeks and 3 months. Further, a higher content of Ca and P was found in the newly formed bone close to granules, in comparison with more distant newly formed bone.

Conclusions: Our results suggest that both resorbable and nonresorbable HA granules promote new bone formation in rabbit cortical defects, which does not occur in control defects.
Clinical Assessment and Surgical Implications of Anatomic Challenges in the Anterior Mandible
Authors: Mraiwa Nuri , Jacobs Reinhilde , van Steenberghe Daniel , Quirynen Marc
Published: October 2006

Background: The anterior mandible is generally considered a rather safe surgical area, involving few risks of damage to vital anatomic structures. Nevertheless, both neurosensory disturbances and hemorrhages have been reported after implant surgery in that particular area.

Purpose: With the increasing demand for oral implant placement, the anatomy of the anterior mandible should receive more attention. This review will focus on the anatomic peculiarities of the anterior mandible and the related clinical implications.

Methods: The scientific evidence on the anatomic, histologic, physiologic, and clinical aspects of the neurovascularization of the anterior mandible will be reviewed.

Results: Surgical complications may be attributed to the existence of a mandibular incisive canal with a true neurovascular supply. Potential risks may also be related to the presence of the lingual foramen and anatomic variations, such as an anterior looping of the mental nerve.

Conclusions: Preoperative radiographic planning for oral implant placement in the anterior mandible should therefore not only consider all esthetic and functional demands but should also pay particular attention to the anatomic peculiarities of this region to avoid any neurovascular complications.
Mk III: A Third Generation of the Self‐Tapping Brånemark System® Implant, Including the New Stargrip Internal Grip Design. A 1‐Year Prospective Four‐Center Study
Authors: Widmark Göran , Friberg Bertil , Johansson Björn , Sindet‐Pedersen Steen , Taylor Åsa
Published: October 2006

Background: Many prospective studies have shown predictable long‐term results of the Brånemark System (Nobel Biocare AB, Gothenburg, Sweden) turned‐surface implants in totally edentulous, partially edentulous, and single cases. The Mk III self‐tapping implant was introduced by Nobel Biocare in 1999 as part of a new implant generation that improved on the Mk II self‐tapping implant that had been introduced in 1992. A new implant design should always be evaluated, preferably in prospective multicenter studies.

Purpose: The aim of the present prospective multicenter study was to evaluate the short‐term success rate of the Br † nemark Mk III machined‐ and turned‐surface self‐tapping implant and to evaluate the clinical handling of the new Stargrip (Nobel Biocare AB) internal grip design.

Materials and Methods: The open prospective 1‐year multicenter study was performed at four clinics. Sixty‐four patients (38 females, 26 males) with a mean age of 51 years (range, 16 to 80 years) were included. Seventeen of the patients were totally edentulous, 26 were partially edentulous, and 21 had single‐tooth losses. In total, 194 Mk III implants were inserted, 89 in the maxillas and 105 in the mandibles.

Results: Fifty‐eight patients were observed for 1 year after prosthetic loading. Three of 194 implants were lost, corresponding to a cumulative success rate of 98.4% after 1 year, 100% for maxillary implants and 97.1% for mandibular implants. The implant driver carried the implants reliably in 99.5% of all treated patients. Sixty‐two patients received the planned prosthetic reconstruction. All but one prosthetic reconstruction survived after 1 year of loading. The mean marginal bone resorption, analyzed from radiographs of 143 implants, was 1.15 mm (standard deviation [SD], 1.09 mm) from the second‐stage surgery to the 1 ‐year follow‐up.

Conclusion: The 1‐year success rate of the Mk III implant was high, and the clinical handling of the internal grip design (Stargrip) improved the surgical technique and was well appreciated by both surgeons and assisting staff.
Cutting Torque Measurements in Conjunction with Implant Placement in Grafted and Nongrafted Maxillas as an Objective Evaluation of Bone Density: A Possible Method for Identifying Early Implant Failures?
Authors: Johansson Björn , Bäck Tomas , Hirsch Jan‐Michael
Published: October 2006

Background:

Bone grafts are frequently used to enable the placement of dental implants in atrophied jaws. The biomechanical properties of bone grafts used in one‐ or two‐stage implant procedures (in comparison with the use of nongrafted bone) are not well known.

Purpose:

The purpose of this study was (1) to measure cutting torques during the placement of self‐tapping dental implants in nongrafted bone and in bone grafts, either as blocks or in a milled particulate form, in patients undergoing implant treatment in an edentulous maxilla and (2) to identify implants with reduced initial stability and to correlate these findings with a clinical classification of jawbone quality.

Materials and Methods:

The study included 40 consecutive patients with edentulous maxillas, 27 of whom were subjected to bone grafting prior to or in conjunction with implant placement (grafting group) and 13 of whom received implants without grafting (nongrafted group). Grafted bone from the iliac crest bone was used (1) as onlay blocks, (2) as maxillary sinus inlay blocks, or (3) in particulate form in the maxillary sinus. Implants were placed after 6 to 7 months of healing, except in the maxillary sinus inlay blocks, where implants were placed simultaneously. Cutting torque values were obtained from 113 grafted implant sites and from 109 nongrafted implant sites.

Results:

Significantly lower cutting torque values were assessed in grafted regions than in nongrafted regions, irrespective of grafting technique. Lower values were also seen for implants placed in block grafts after 6 months when compared to other grafting techniques used. The cutting torque values revealed an inverse linear relation to the Lekholm and Zarb bone quality index.

Conclusion:

The cutting torque values correlated well with the Lekholm and Zarb index of bone quality. Significantly lower cutting torque values were seen in grafted bone than in nongrafted bone.
Carbon Dioxide Laser and Hydrogen Peroxide Conditioning in the Treatment of Periimplantitis: An Experimental Study in the Dog
Authors: Persson Leif G. , Mouhyi Jafaar , Berglundh Tord , Sennerby Lars , Lindhe Jan
Published: October 2006

Background:

Various methods have been applied for the treatment of periimplantitis lesions. It has been reported that the procedures used have been effective in eliminating the inflammatory lesion but that re‐osseointegration to the once‐contaminated implant surface has been difficult or impossible to achieve.

Purpose:

The aim of this study was to examine the use of carbon dioxide (CO2) laser in combination with hydrogen peroxide in the treatment of experimentally induced periimplantitis lesions.

Materials and Methods:

Three dental implants (ITI Dental Implant System®, Straumann AG, Waldenburg, Switzerland) were placed in each side of the edentulous mandible of four beagle dogs. Implants with a turned surface and implants with a sand‐blasted large‐grit acid‐etched (SLA) surface (SLA®, Straumann AG, Waldenburg, Switzerland) were used. Experimental periimplantitis was induced during 3 months. Five weeks later each animal received tablets of amoxicillin and metronidazole for a period of 17 days. Three days after the start of the antibiotic treatment, full‐thickness flaps were elevated, and the granulation tissue in the bone craters was removed. In the two anterior implant sites in both sides of the mandible, a combination of CO2 laser therapy and application of a water solution of hydrogen peroxide was used. The implant in the posterior site of each quadrant was cleaned with cotton pellets soaked in saline. Biopsy specimens were obtained 6 months later.

Results:

The amount of re‐osseointegration was 21% and 82% at laser‐treated turned‐surface implants and SLA implants, respectively, and 22% and 84% at saline‐treated turned‐surface implants and SLA implants, respectively.

Conclusions:

The present study demonstrated the following: (1) a combination of systemic antibiotics and local curettage and debridement resulted in the resolution of experimentally induced periimplantitis lesions; (2) at implants with a turned surface, a small amount of re‐osseointegration was observed at the base of the bone defects whereas a considerable amount of re‐osseointegration occurred at implants with an SLA surface; and (3) the use of CO2 laser and hydrogen peroxide during surgical therapy had no apparent effect on bone formation and re‐osseointegration.
Nightguard Vital Bleaching of Tetracycline‐Stained Teeth: 90 Months Post Treatment
Authors: LEONARD RALPH H. , HAYWOOD VAN B. , CAPLAN DANIEL J. , TART NATILE D.
Published: October 2006

Purpose: The purpose of this longitudinal whitening study was to determine the stability, post‐treatment side effects, and patient satisfaction at 90 months post treatment after 6 months of active treatment of tetracycline‐stained teeth with 10% carbamide peroxide.

Materials and Methods: Fifteen of 21 participants enrolled in the study (71%) were contacted and asked to participate in a survey concerning their whitening experience. Participants were asked whether there had been any change in the shade of their teeth after treatment and if they had experienced any side effects that they believed were treatment related. Eight of the 15 participated in a clinical examination.

Results: Nine participants (60%) reported no obvious shade change or only a slight darkening not noticed by others. None reported darkening back to the original shade; however, four had re‐treated their teeth. Examiners were in agreement with the participants' perception of shade change upon comparing pretreatment and post‐treatment photographs and Vita® shade (Vita Zahnfabrik D‐79713, Bad Sackingen, Germany) values. The degree of improvement over the pretreatment shade was significant for the 90‐month post‐treatment shade (p < .01). All respondents (n = 15) denied having to have a crown or root canal or tooth sensitivity that they believed was treatment related.

CLINICAL SIGNIFICANCE

The results of this study of nightguard vital bleaching indicate that tetracycline‐stained teeth can be whitened successfully using extended treatment time and that shade stability may last at least 90 months post treatment (range 84–100 mo). Patients participating in this study were over‐whelmingly positive about the procedure in terms of shade retention and lack of post‐treatment side effects.
The ZiReal Post: A New Ceramic Implant Abutment
Authors: BRODBECK URS
Published: October 2006

Restorations in the anterior esthetic zone present significant challenges in both the surgical and prosthetic phases of implant dentistry. Titanium has been established as the material of choice for endosseous implants, resulting in a high degree of predictability. Many types of implants require transmucosal abutments to retain implant restorations. Ceramics may be the ideal material to replace natural teeth, but most transmucosal abutments are made of titanium. However, ceramics may also be used as abutments in implant restorations. This combination of ceramics for abutment and crown provides better translucency for the implant restoration than is available with metal abutments and porcelain‐fused‐to‐metal crowns. Ceramic abutments and implant restorations also minimize the gray color associated with metal components that is transmitted through the peri‐implant tissues. Customized emergence profiles also may be obtained with ceramic abutments; this generally improves the predictability and consistency of the esthetics obtainable in implant restorations. Zirconia as a ceramic material offers not only outstanding material properties but also a well‐documented biocompatibility.

CLINICAL SIGNIFICANCE

This article discusses the clinical and laboratory features of a new ceramic abutment, ZiReal™ Post (Implant Innovations, Inc., Palm Beach Gardens, Florida).
Effect of Polishing Systems on the Surface Roughness of Microhybrid Composites
Authors: LU HUAN , ROEDER LESLIE B. , POWERS JOHN M.
Published: October 2006

Purpose: This study was undertaken to examine the effect of three different polishing systems on surface roughness of five newly developed resin composites.

Materials and Methods: Three microhybrid composites (Point 4™, Kerr, Orange, CA; Esthet‐X™, Dentsply/Caulk, Milford, DE; Vitalescence®, Ultradent, South Jordan, UT, USA), one microfilled composite (Renamel Microfill®, Cosmedent, Chicago, IL, USA), and one experimental micro‐hybrid composite (FZB, Ivoclar Vivadent, Schaan, Liechtenstein) were light cured with a Mylar strip. Fifteen specimens of each composite (6 mm in diameter and 3 mm in depth) were fabricated and randomly assigned to three groups. Specimens in each group were finished with a carbide bur (16 fluted) and three polishing systems (Astropol®, Ivoclar Vivadent; Diagloss®, Axis Dental, Irving, TX, USA; Sof‐Lex™, 3M, ESPE, St. Paul, MN, USA). The average surface roughness (Ra) and the mean peak spacing (Sm) were measured with a surface profilometer after polishing. Five tracings at different locations on each specimen were made. Data were analyzed by analysis of variance.

Results: For Astropol, Ra ranged from 0.10 to 0.15 um and Sm ranged from 24 to 40 um for the five composites; for Diagloss, Ra ranged from 0.24 to 0.34 um and Sm from 38 to 74 urn; for Sof‐Lex, Ra ranged from 0.06 to 0.10 um and Sm ranged from 16 to 22 um. Significant differences between materials and polishing systems were observed. Polishing systems had the most important role in determining the surface roughness of resin composites.

CLINICAL SIGNIFICANCE

Of the polished systems tested, Sof‐Lex discs provided the lowest roughness for polishing microfilled and microhybrid composites, and the microfilied resin composite showed the lowest roughness.
Critical Appraisal
Authors: Geirsson Jonas , Sigurdsson Asgeir , Swift Edward J.
Published: October 2006

Unrestored endodontically treated teeth are structurally compromised and remain one of the greatest challenges to today's dental clinician. Over the years many post materials and designs have been evaluated for strength, stress to dentin, retentiveness, and esthetics. Because many types of posts are available, the requirements of each specific clinical situation must be carefully evaluated. A better understanding of how to protect remaining tooth structure and the use of scientifically based concepts of restoring endodontically treated teeth will help us to develop sound biomechanical design principles and reach satisfactory final restorations. This critical appraisal focuses on comparisons of different post systems; stress effects on tooth structure, strength, and flexibility; and retrievability after failure. Furthermore it addresses whether post reinforcement should be used in incisors.
Efficacy of a Resin Coating on Bond Strengths of Resin Cement to Dentin
Authors: JAYASOORIYA PRIMALI R. , PEREIRA PATRICIA N.R. , NIKAIDO TORU , TAGAMI JUNJI
Published: October 2006

Purpose: The aims of this study were to (1) evaluate the effect of a resin coating consisting of a dentin bonding system and a flowable resin composite on the microtensile bond strength (μ‐TBS) of a resin cement to dentin in indirect composite restorations and (2) compare the bond strengths of direct and indirect composite restorations.

Materials and Method: Occlusal surfaces of human premolars were ground to obtain flat dentin surfaces and were divided into seven groups. For indirect restorations, the dentin surfaces of the experimental groups were bonded with a dentin bonding system (DBS), Clearfil SE Bond (SE) or Single Bond (SB) with and without a flowable resin composite, Protect Liner F (PLF), temporized for one day and cemented with a resin cement (Panavia F) according to the manufacturer's instructions. The dentin surfaces of the control group were temporized without prior treatment, and indirect composite (Estenia) was bonded with Panavia F. For the direct restorations, either SE or SB was applied to the dentin surface and the entire surface was built up with direct composite (Clearfil AP‐X). After 24 hours in water storage, μ‐TBS was measured at a crosshead speed of 1 mm/min. The data were analyzed with one‐way analysis of variance and Fisher's protected least significant difference test (p < .05).

Results: The original bond strength of the resin cement (Panavia F) to dentin significantly improved with the use of a resin coating technique in indirect restorations (p < .05). The combination of DBS + PLF showed significantly higher bond strengths compared with the single use of DBS. The combination of SE + PLF as a resin coating provided the highest bond strengths in indirect restorations (p < .05). However, the best bond strengths were observed when SE and SB were used for direct composite restorations (p < .05).

Conclusions: The application of a resin coating consisting of a dentin bonding system and a flowable resin composite on the dentin following cavity preparation significantly improved the μ‐TBS of the resin cement Panavia F to dentin in indirect restorations. However, the bond strengths of indirect composite restorations were significantly lower than those of direct composite restorations even with the resin coating technique.

CLINICAL SIGNIFICANCE

Indirect composite restorations may require a resin coating to improve the bonding performance of the resin cement Panavia F to dentin. However, adhesive systems with direct composite restorations still provide superior bond strengths compared with indirect restorations.
Perspectives
Authors: Christensen Gordon J.
Published: October 2006

Few people in dentistry command greater respect and admiration than does Dr. Gordon Christensen. For years Dr. Christensen has not only kept in touch with the pulse of the profession but also has been, in many respects, dentistry's conscience. A founding member of the American Academy of Esthetic Dentistry, Dr. Christensen is clearly one of dentistry's most revered elder statesmen. For this reason, I felt compelled to reprint a recent editorial that he wrote that should be a “wake‐up call” for all of us in dentistry.—Harald O. Heymann, DDS, MEd, Editor‐in‐Chief
Multidisciplinary Approach in the Treatment of a Patient with Cleft Lip and Palate: A Case Report
Authors: ABARCA MARCELO , BUDZYNSKI YVES , KOVACS BLAISE , MALEVEZ CHANTAL
Published: October 2006

Treatment of the patient with cleft lip and palate represents a real problem from both functional and esthetic points of view. Today a functional result is not enough. An esthetic result is both necessary and possible to improve the quality of life. The direct placement of an implant in the grafted alveolar cleft is not the ideal choice.

Using a rational, multidisciplinary approach, it is possible to obtain esthetic results in these patients. In our case study, a 17‐year‐old patient previously treated for a unilateral cleft lip and palate and agenesis of the right lateral incisor was given an osseointegrated implant. Computer‐assisted dental design (Procera® CAD/CAM software, Nobel Biocare AB, Gothenburg, Sweden) was used for the prosthetic rehabilitation, and the end of growth was determined prior to placing the implant.

No sign of failure or mobility after loading has been detected at the time of this writing, 8 months after the procedure's completion, and the esthetic result is considered satisfactory by the patient and practitioners.
Effect of Bleaching and Repolishing Procedures on Coffee and Tea Stain Removal from Three Anterior Composite Veneering Materials
Authors: TÜRKÜN L. ŞEBNEM , TÜRKÜN MURAT
Published: October 2006

Discolored teeth can be treated with resin veneers, but their color changes when confronted with staining solutions. Polishing procedures can provide a remedy for highly stained composites, but they tend to remove some materials as well. However, bleaching procedures are an effective, nondestructive method for solving the problem. The aim of this study was to compare the color change of three veneer composites exposed to staining solutions and to evaluate the effectiveness of a 15% hydrogen peroxide bleaching agent and three polishing systems to remove the stain.

Forty‐five disks (12 × 2 mm) each of Clearfil ST® (Kuraray Co. Ltd., Osaka, Japan), Esthet‐X™ (Dentsply/Caulk, Milford DE, USA), and Filtek A110™ (3M ESPE, St. Paul, MN, USA) were prepared. The specimens were polished with Sof‐Lex™ (3M ESPE), Enhance® (Dentsply/Caulk), or PoGo® (Dentsply/Caulk). Five specimens for each material‐polishing system combination were immersed in coffee (Nescafe® Classic, Nestle SA, Vevey, Switzerland) or tea (Earl Grey, Lipton, Blackfriars‐London, England) for 7 days. The remaining disks were stored in water. Color measurements were made with a spectrophotometer (X‐Rite® Seroice SP78, Loaner, Köln, Germany) at baseline; after 1, 3, 5, and 7 days; and after bleaching and repolishing. After 1 week, one side of the specimens was bleached with Illuminé‐office® (Dentsply De Trey GmbH, Konstanz, Germany) for 1 hour, and the other side was repolished for 30 seconds. All comparisons of color change for the polishing systems, times, and staining solutions were subjected to repeated measurements of analysis of variance. Paired t‐test was used to examine whether significant color differences (δE*) occurred during immersion at the specified time intervals (p .05).

Filtek A110 was the least stained resin composite. Its color remained under a δE* value of 2 during the study. Clearfil ST exhibited the most color change after 1 week. All specimens polished with Enhance showed less staining, whereas those polished with the Sof‐Lex system demonstrated the most color change. Water did not cause a variance in the δE*. There was no difference in the staining potential of coffee and tea. Bleaching and repolishing were effective in removing the stains. The resin composites tested reversed nearly to baseline color with the bleaching and to less than values at 1 day of staining with repolishing.

The coffee and tea brands tested stained the composites used in this study equally. In‐office bleaching was found to be more effective than repolishing in the restitution of the color.
OXYGEN‐INHIBITED LAYER IN ADHESION DENTISTRY
Authors: Suh Byoung I.
Published: October 2006

Purpose::

Characteristics of the oxygen‐inhibited layer, including bond strength, photoinitiator decomposition, and post‐curing degree of conversion, were investigated.

Materials and Methods:

To investigate shear bond strength, BisCover (Bisco, Inc., Schaumburg, IL, USA) and D/E Resin (Bisco, Inc.) were placed on disks of Renew composite (Bisco, Inc.) and cured both with and without an oxygen‐inhibited layer. Light‐Bond composite (Reliance Orthodontic, Itasca, IL, USA) was placed in a gelatin capsule and light cured over the cured resin. After soaking in water for 2 hours at 37°C, specimens were sheared to failure using a universal testing machine (Model 4466, Instron Inc., Canton, MA, USA).

To investigate microtensile bond strength, composite substrates prepared using Renew A2 composite were light cured either in air or under nitrogen. Light‐Core (Bisco, Inc.) was placed on each substrate and light cured. The resulting specimens were sectioned into composite beams and stressed to failure using a microtensile tester (built by Bisco, Inc.).

To determine camphorquinone (CQ) decomposition, an experimental CQ resin was placed between two glass plates and irradiated for different time intervals. The absorption spectrum was obtained using a Cary 50 Bio UV‐Visible Spectrometer (Varian, Mulgrave, Australia).

To explore the degree of conversion, polyester film strips (Mylar, DuPont, Wilmington, DE, USA) coated with the CQ resin were pre‐cured in air for different time periods, and then post‐cured at low intensity for 5 minutes under nitrogen. A Spectrum 1000FTIR Spectrometer (Perkin Elmer, Norwalk, CT, USA) was used to measure the degree of conversion.

Results:

Bond strength tests resulted in no significant difference between samples with or without an oxygen‐inhibited layer. The oxygen‐inhibited layer contained reduced amounts of photoinitiator. The degree of conversion of post‐cured oxygen‐inhibited layers was lower than that for the control.

Conclusion:

An oxygen‐inhibited layer is not necessary for bonding with composite resin.
DURABILITY OF ENAMEL BOND STRENGTH OF SIMPLIFIED BONDING SYSTEMS
Authors: Miyazaki M. , Sato M. , Onose H.
Published: October 2006

Objective: The purpose of this study was to determine the effect of thermal cycling on the enamel bond strengths of two‐step adhesive systems, either self‐etching primers or “one‐bottle” total‐etch systems, to bovine enamel.

Materials and Methods: Three self‐etching primer systems–Imperva Fluoro Bond® (Shofu Inc., Kyoto, Japan), Clearfil® Liner Bond II (Kuraray Co. Ltd., Osaka, Japan), and Mac Bond® II (Tokuyama Corp., Tokyo, Japan)–and four total‐etch adhesive systems–One‐Step® (Bisco Inc., Schaumburg, IL, USA), Opti‐Bond Solo® (Kerr Corporation, Orange, CA, USA), Prime & Bond® 2.0 (Dentsply DeTrey, Konstanz, Germany), and Single BondTM (3M ESPE, St. Paul, MN, USA)–were used. Labial enamel surfaces of bovine incisors were exposed by grinding with 240‐grit and 600‐grit wet silicon carbide paper. Enamel was treated according to the manufacturers' instructions. Following the application of adhesive resin, resin composites were condensed into a mold (diameter = 4 mm, depth = 2 mm) and were light‐cured. Bonded specimens were stored in 37°C water for 24 hours. They were divided into a control group (no thermal cycling) and three experimental groups with thermal cycles of 3,000, 10,000, and 30,000 cycles, respectively, between 5°C and 60°C. The shear test was performed at a crosshead speed of 1.0 mm/min. The ultrastructure of resin‐enamel interfaces was observed by SEM at times 3,500 magnification.

Results: Self‐etching primer systems had significant decreases in enamel bond strengths with thermal cycling. In contrast, total‐etch systems had no significant differences, except for One‐Step. Mixed failures were predominant in these systems, but adhesive failures tended to increase with a greater number of thermal cycles. SEM observations revealed small cracks at the resin‐enamel interface for self‐etching primer systems when subjected to 30,000 thermal cycles.

Conclusions: Enamel shear bond strengths after thermal cycling of self‐etching primer systems appeared to be less stable than were those of total‐etch adhesive systems.
Rare case of malignant duodenal tumor presenting with unusual complications in a child
Authors: VAIPHEI Kim , BHATIA Alka , WALIA Anuj , LAL Sadhana , THAPA Babu Ram
Published: October 2006

The report highlights a rare case of duodenal anaplastic large cell lymphoma in a child who presented with duodeno‐colic fistulization. The child responded to a cyclophosphamide, doxorubicin, vincristine and prednisolone regime but the fistula required surgical resection. The child is disease free at 24 months of follow up.
CHEMICAL AND MICROBIOLOGICAL QUALITIES OF DRY‐SALTED (LAKERDA) BONITO (SARDA SARDA, BLOCH 1793)
Authors: TURAN HÜLYA , KAYA YALÇIN , ERKOYUNCU İBRAHİM , SÖNMEZ GÜLŞAH
Published: October 2006

In this study, changes in the chemical and microbiological properties of bonito (Sarda sarda, Bloch 1793) salted by dry salting (lakerda) and stored for 6 months at 4 ± 1C were investigated. The fresh gutted and sliced bonitos were used as raw material for salting by using the ratio of fish to salt as 5:1 by weight. Salted fish remained in the liquid pickle formed by salt and the liquid extracted from the fish. This solution was not drained during the storage period. The product is described as “lakerda” in Turkey. In the fresh fish, total volatile basic nitrogen (TVB‐N) and trimethylamine nitrogen (TMA‐N) values were 11.21 mg/100 g and 1.19 mg/100 g, respectively. During the storage period, TVB‐N and TMA values increased slowly to 27.67 mg/100 g and 4.99 mg/100 g, respectively, at the end of the storage period. In the first month after salt processing, the total mesophilic bacteria count was 4.6 × 102 cfu/g. In the later months, mesophilic, psychotropic, coliform bacteria and yeast‐mold did not reproduce. According to the results, bonito salted by dry salting and stored at 4 ± 1C was in good quality in terms of chemical and microbiological properties during the storage period of 6 months.
SEASONAL VARIABILITY OF CHEDDAR CHEESE WHEY POWDER: A CASE STUDY
Authors: SITHOLE RHODA , MCDANIEL MINA RAE , GODDIK LISBETH MEUNIER
Published: October 2006

Cheddar whey powder from one plant was evaluated for variations in quality parameters over 12 months. Representative samples were analyzed monthly for microbiological, physicochemical and sensory properties. The seasonal variability in the physicochemical properties was minor. Fall samples were higher in Hunter Lab parameter L* (lightness) and pH but lower in solubility index. Summer samples were high in solubility index and titratable acidity but low in L*. May production was significantly higher in standard plate count (SPC) and free moisture than the rest of the year. February production was significantly lower in SPC and free moisture content. There were no significant differences in aroma and flavor across the seasons. The flavor was generally bland, with the most intense attribute rating 5 on the 15‐point intensity scale. The order of intensity of the most intense attributes was cooked flavor and aroma > sweetness > caramelized flavor and aroma.
A Conceptual Model of Community Capacity for Biodiversity Conservation Outcomes
Authors: MOORE SUSAN A. , SEVERN ROGER C. , MILLAR REBECCA
Published: October 2006

In Australia an unprecedented level of attention is being paid to improving the sustainable management of agricultural lands. As of 2005, the Australian government had committed over four billion dollars to land, water and biodiversity management programmes. Most is being allocated to regional community groups. Central to programme delivery is attention to community capacity and the desire to build capacity to implement changes in land and water management. This paper addresses the fundamentally important question ‘what is community capacity?’ through developing and refining a conceptual model of community capacity to deliver biodiversity conservation outcomes. Model development was based on a literature review and synthesis, with subsequent refinement using interviews. From the literature, community capacity was described as five forms of capital: natural, social, human, institutional and produced economic. The model was refined using interviews with Greening Australia (an environmental non‐government organisation) field staff. Their responses identified all five forms of capital as important elements of community capacity. Social and human capital were mentioned by almost all respondents, with limited mention being made of the other capitals. Social capital included cognitive and structural dimensions. Knowledge, skills and experience were part of human capital. These results provide researchers and practitioners with assurance that social and human capital indicators can be confidently sought to describe capacity. There is also sufficient guidance from these results to progress indicator selection for the remaining forms of capital provided that selection is accompanied by continuing refinement of our descriptions of these forms.
The Canary in the Coalmine: Australian Ski Resorts and their Response to Climate Change
Authors: BICKNELL SHARON , MCMANUS PHIL
Published: October 2006

The Australian ski industry represents a ‘canary in the coalmine’. Globally, it is one of the first and most visibly impacted industries by the risk of climate change. This study explores the perceptions of people associated with the operations of ski resorts in south‐eastern Australia. It was hypothesised that ski resorts, given the value of their assets, would anticipate and respond to the threat of climate change. The responses demonstrate how representatives of the Australian ski industry perceive climate change issues, and the measures that are being taken to address this issue at particular resorts. These responses provide insights into how other firms and industries might respond to the biophysical impacts of climate change. Using in‐depth interviews, the study compares the perceptions and responses of resort managers and government representatives with those from previous studies. The analysis draws on and improves the model of the Intergovernmental Panel on Climate Change and its development as a policy framework for adaptation. The major findings of this study are that a physical meltdown may not lead to a financial meltdown, that business responses to climate changes are more varied than has been represented in the literature to date and that the tension between competing firms on the one hand and industry cooperation on the other strongly influences the types of response that may develop.
The Whole-Brain Concept of Death Remains Optimum Public Policy
Authors: Bernat James L.
Published: October 2006

The definition of death is one of the oldest and most enduring problems in biophilosophy and bioethics. Serious controversies over formally defining death began with the invention of the positive-pressure mechanical ventilator in the 1950s. For the first time, physicians could maintain ventilation and, hence, circulation on patients who had sustained what had been previously lethal brain damage. Prior to the development of mechanical ventilators, brain injuries severe enough to induce apnea quickly progressed to cardiac arrest from hypoxemia. Before the 1950s, the loss of spontaneous breathing and heartbeat (“vital functions”) were perfect predictors of death because the functioning of the brain and of all other organs ceased rapidly and nearly simultaneously thereafter, producing a unitary death phenomenon. In the pretechnological era, physicians and philosophers did not have to consider whether a human being who had lost certain “vital functions” but had retained others was alive, because such cases were technically impossible.
Owning up to Our Agendas: On the Role and Limits of Science in Debates about Embryos and Brain Death
Authors: Khushf George
Published: October 2006

”Merely fact-minded sciences make merely factminded people.”

“ …the positivistic concept of science in our time is, historically speaking, a residual concept. It has dropped all the questions which had been considered under the now narrower, now broader concepts of metaphysics….all these ‘metaphysical’ questions, taken broadly – commonly called specifically philosophical questions – surpass the world understood as the universe of mere facts. They surpass it precisely as being questions with the idea of reason in mind. And they all claim a higher dignity than questions of fact, which are subordinated to them even in the order of inquiry. Positivism, in a manner of speaking, decapitates philosophy.”

Edmund Husserl

In ethical literature associated with controversies at the beginning and end of human life, there is often a two-part structure: first, basic facts about the topic are presented in a more or less descriptive format, then there is the ethics or policy.
Direct Anatomical Localization of the Subthalamic Nucleus on CT with Comparison to Schaltenbrand-Wahren Atlas
Authors: Sather Michael D. , Patil Arun Angelo
Published: October 2006

Stimulation of the subthalamic nucleus (STN) has become an accepted treatment for motor symptoms of Parkinson’s disease. Generally, localization of the target is based on stereotactic atlas coordinates and magnetic resonance (MR) images. In this paper a method of direct anatomical localization of the STN on computed tomography (CT) images is described and compared with the Schaltenbrand-Wahren atlas. Serial CT scans were obtained at 1.5-mm interval and scan thickness of 3 mm, with the CT gantry and glabella-inion plane of the patient’s head vertical. The STN was identified as a dense structure medial to the inner semicircular border of the internal capsule in the subthalamic region. Its visibility was increased by changing the window and level settings on the CT workstation computer. The center of the STN in relationship to the intercommissural line, determined by this technique, was similar to those found on standard atlases.
The Impact of a Changing Southern Hemisphere Annular Mode on Antarctic Peninsula Summer Temperatures
Authors: Marshall Gareth J. , Orr Andrew , van Lipzig Nicole P. M. , King John C.
Published: October 2006

Since the mid-1960s, rapid regional summer warming has occurred on the east coast of the northern Antarctic Peninsula, with near-surface temperatures increasing by more than 2°C. This warming has contributed significantly to the collapse of the northern sections of the Larsen Ice Shelf. Coincident with this warming, the summer Southern Hemisphere Annular Mode (SAM) has exhibited a marked trend, suggested by modeling studies to be predominantly a response to anthropogenic forcing, resulting in increased westerlies across the northern peninsula.

Observations and reanalysis data are utilized to demonstrate that the changing SAM has played a key role in driving this local summer warming. It is proposed that the stronger summer westerly winds reduce the blocking effect of the Antarctic Peninsula and lead to a higher frequency of air masses being advected eastward over the orographic barrier of the northern Antarctic Peninsula. When this occurs, a combination of a climatological temperature gradient across the barrier and the formation of a föhn wind on the lee side typically results in a summer near-surface temperature sensitivity to the SAM that is 3 times greater on the eastern side of the peninsula than on the west. SAM variability is also shown to play a less important role in determining summer temperatures at stations west of the barrier in the northern peninsula (∼62°S), both at the surface and throughout the troposphere. This is in contrast to a station farther south (∼65°S) where the SAM exerts little influence.