Quintessence International, 04/2001

Objective: The treatment procedures used in conjunction with two different metal-free restorative systems are illustrated on the basis of clinical examples. In addition, a report on the initial clinical findings is provided. Method and materials: Metal-free restorative materials are opening doors to new preparation methods because of their close link to the adhesive cementation technique. As a result of the developments over the past few years, various metal-free systems that can be used to fabricate short-span fixed partial dentures (FPD) are now available. Certain guidelines, however, must be observed in the process. Because of their minimal invasiveness, inlay-retained FPDs offer an interesting solution in cases where the residual dentition exhibits low caries activity. Since the beginning of 1997, a total of 23 metal-free inlay-retained FPDs made of two different types of framework material (11 of high-strength pressed ceramic and 12 of fiber-reinforced composite) have been examined in a clinical study. Results: One inlay-retained FPD made of pressed ceramic had to be replaced because of a fracture. Because the materials have only been on the market for a short time, long-term results are not yet available. Conclusion: This type of restoration provides excellent esthetics and reduced invasiveness compared with complete crown-retained FPDs, although indications are limited by the special mechanical properties of the material.

Talon cusp is an uncommon condition often present in the maxillary incisors and mandibular premolars. Morphologically, this anomaly has a well-delineated cusp that extends at least half the distance from the cementoenamel junction or cingulum area to the incisal edge. The alteration can cause clinical problems such as caries or occlusal interference. Management of the talon cusp varies according to the circumstances of the individual case and should be as conservative as possible. Presented is a case of bilateral bifid talon cusp in maxillary central incisors that was successfully managed with conservative therapy.

Objective: The purpose of this study was to test the support of occlusal enamel by amalgam (Dispersalloy), bonded amalgam (AmalgamBond Plus adhesive system with high-performance additive powder and Dispersalloy amalgam), and a bonded resin composite (Scotchbond Multi-Purpose adhesive system and Z100 resin composite). Method and materials: For each material, 16 human molars were prepared. The lingual cusps were removed, and the dentin supporting the facial cusps was cut away, leaving a shell of enamel. Each group of prepared teeth was restored using the materials according to manufacturers' instructions. All specimens were thermocycled (1,500 cycles, 6°C to 60°C, dwell time 30 seconds), then mounted vertically in cast stone. A separating disk, mounted horizontally, was used to create a flat horizontal surface approximately 1.5 mm wide at the tips of both remaining enamel cusps of each specimen. Specimens were loaded evenly across the cusp tips at a crosshead speed of 10 mm/min until the fracture occurred. Results: Data were analyzed using analysis of variance and Tukey A post hoc analysis. No significant difference was detected among amalgam, bonded amalgam, and bonded resin composite in their ability to support occlusal enamel. Support provided for occlusal enamel by the materials, whether bonded or not, was intermediate between no support and that provided by dentin. Conclusion: Without further development of materials technology and evidence of efficacy, restorative materials should not be relied upon to support undermined occlusal enamel.

Objective: The purpose of this study was to assess Pertac II restorations placed in general dental practice. Method and materials: A total of 86 restorations (14 Class I, 10 Class II, 17 Class III, 5 Class IV, and 40 Class V) using a hybrid composite material (Pertac II) placed in 56 patients (mean age, 39 years) in 5 dental practices in the United Kingdom were assessed after 1 year by a trained evaluator and the dental practitioner who had placed the restoration. All the restorations were assessed for anatomic form, marginal adaptation, surface roughness, sensitivity or discomfort, gingival condition, and the presence or absence of secondary caries. Results: Thirty-five (43%) restorations were placed in load-bearing situations, 9% of which were assessed as being in heavy occlusion. Five (6%) of the restorations were lost (all Class V restorations), 4 from premolars and 1 from a molar. Four were in wedge-shaped cavities and 1 small restoration was actually dislodged during examination. The remaining 81 (94%) restorations were found to be intact, with no secondary caries detected. A high percentage of optimal scores were recorded for both anatomic form and surface roughness. Conclusion: It is concluded that the evaluation demonstrated satisfactory clinical performance of Pertac II restorations after 1 year of clinical service in the wide variety of clinical situations seen in general dental practice. However, the potential for failure of hybrid composite materials in Class V situations appears high. It may be argued that clinicians who wish to use a resin-based material in a Class V situation should use a compomer or microfilled composite.

Root fractures of posterior teeth, which are defined as fractures involving cementum, dentin, and pulp, are relatively uncommon among dental traumas. This study describes an unusual horizontal fracture of a mandibular second premolar. The tooth was asymptomatic and the fracture unnoticed until the crown broke off completely. The patient had no recollection of a causative event nor was there any evidence of previous physical trauma. The tooth was extracted, embedded in resin, sliced, and examined with different light microscopes. It was concluded that the tooth had been damaged previously but not to the extent that the pulp was seriously damaged. Resorption over a period of time eventually caused the final fracture.

A 10-year-old boy presented with generalized gingival inflammation, extensive alveolar bone loss, and tooth mobility. Clinical and radiographic examination supplemented by microbiologic investigation led to a diagnosis of classically termed prepubertal periodontitis (now known as generalized aggressive periodontitis). Other than severe periodontitis, the child was systemically healthy. Neither unusual infections nor abnormalities in neutrophil functions were detected. Microbiologic examinations by culture revealed the presence of the periodontal pathogen Actinobacillus actinomycetemcomitans. Treatment consisted of extraction of mobile teeth, supragingival and subgingival debridement, subgingival curettage, and root planing combined with a 1-week prescription of a combination of metronidazole and amoxicillin. Scanning electron microscopy of extracted teeth revealed hypoplastic and aplastic cementum at the periodontally exposed and intact surfaces. Clinical and microbiologic follow-up was continued over a 1-year period. No periodontal lesions have been detected, and A actinomycetemcomitans could not be isolated from the subgingival areas of the remaining teeth at the end of the first year. Since A actinomycetemcomitans was the main pathogen present in the subgingival microflora of the patient, it might play a key role in the etiology of prepubertal periodontitis.

Objective: The Hidep risk management model has been developed and tested in clinical settings with promising results, but a tool facilitating the work has been suggested. The aim of the present study was to create and evaluate a computerized tool capable of creating overviews of the oral health situation as well as identifying risk factors and at-risk patients. The system developed should also facilitate the clinical work, for example, by assisting the user with automatic calculation of suitable Hidep groups and selection and printing of relevant patient information letters. Method and materials: The system developed was based on the Hidep model, combining a number of available examination methods, risk estimation systems, and treatment suggestions. The development strategy included stepwise improvements and functionality increase based on continuous clinical applicability tests in a large international test bed. Results: The results indicated that the software created was user friendly enough to be used in a common dental clinic and capable of handling the basic data of both patients and their oral health situation. The system could present useful statistics and graphs describing the overall oral health situation and identifying relevant risk groups and risk factors, based on virtually unlimited parameter combinations. Conclusion: The computer system developed seems to be an important step toward the possibility of creating a close-to-the-clinic model for oral health care management based on actual and locally derived patient data and risk factors. The results of this project encourage further studies of the Hidep model and its computer support.

Jeanne Craig Sinkford graduated from Howard University College of Dentistry in 1958 and there began a career in academic dentistry as a clinical instructor. Six years later, armed with specialty training in prosthodontics and a master's degree and PhD in physiology from Northwestern University, Dr Sinkford returned to Howard expecting to develop a research program and continue her clinical teaching. Instead, she was immediately made head of the Department of Prosthodontics and in 11 more years became Howard's dean of dentistry. After 16 years as dean, Dr Sinkford retired and took a position at the American Dental Education Association charged with developing and implementing policy on issues involving gender and minorities in dentistry. In addition to her reputation for her principled approach to getting things done, Dr Sinkford is widely recognized for her dedicated sincerity, her warmth, her concern for others, and her reasoned reasonableness.