Quintessence International, 04/2002

Since the introduction of microsurgical principles in the 1990s, the field of endodontic surgery has made continuous and substantial progress. Particularly, root-end cavity preparation has been simplified and optimized by means of newly developed surgical microinstruments. However, the successful outcome of endodontic surgery depends to a large extent on accurate intraoperative diagnostics. Conventionally, micromirrors (retromirrors) and microprobes have been used for this purpose. Recently, the surgical microscope has been used to enhance visibility during dental procedures. In addition, endoscopy has been reported to provide the surgeon with outstanding vision and ease of use. This article describes the technical specifications and the diagnostic application of the endoscope during endodontic surgery.

Objective: This study evaluated the biologic ability of sodium hypochlorite to control hemorrhage via chemical amputation of the coagulum, to remove dentin chips, to assist healing, and to facilitate formation of a dentinal bridge under two adhesive systems. Method and materials: Ninety Class V cavities with mechanical pulpal exposures were placed in the teeth of five adult monkeys and histologically observed. All exposures were prepared with a No. 330 bur, and hemorrhage was controlled with 3% sodium hypochlorite. Twenty-two exposures were capped with All-Bond 2 and Ælitefil, and 26 exposures were capped with One-Step (OS) and Resinomer (RS). Two pulps were excluded from the final data. Forty-two exposures were capped with calcium hydroxide and amalgam as controls. At 7, 27, and 90 days, tissues were obtained by perfusion fixation, demineralized, sectioned, stained, and histologically graded according to published qualitative criteria. Results: For both adhesives, at 7 days, 12 of 16 pulps showed no coagulum remnants or dentin chips at the material interface. No necrotic pulps were observed. At 27 and 97 days, 26 of 30 capped pulps had dentinal bridges at the adhesive interface. Reparative dentin was present in 28 pulps. Four 97-day pulps exhibited necrosis associated with stained bacteria. One 97-day pulp contained dentin chips throughout the pulp and demonstrated no healing, no reparative dentin, and no stained bacterial profiles. Conclusion: Normal soft tissue reorganization and dentinal bridge formation were observed in 86% of pulps treated with sodium hypochlorite and either adhesive system.

Objective: The aim of this study was to evaluate the effect of different cavity designs, cavity depths, and shade matching on the dimensions of Class I resin-based composite preparations during replacement of the restoration. Method and materials: Forty Class I cavity preparations were prepared in extracted premolars. The occlusal depths varied from 1.5 to 2.5 mm. In 20 teeth, the buccal and lingual walls were perpendicular to the pulpal floor; in another 20, they were divergent to the pulpal floor. Impressions were made of all preparations. The cavities were restored with resin-based composite. All subgroups were further divided into another two subgroups (n = 5), in which half of the teeth were restored with shade that matched the tooth and the other half were restored with a resin composite that was three shades different from the tooth. After 168 hours in distilled water, the restorations were removed. New impressions were made, and a total of 80 stone casts were fabricated. The perimeter and area of the restorations were recorded with a video-based imaging system. The dimensions of the postoperative cavity preparations were compared to the initial cavity sizes. Results: The depth of the original cavity preparation had a statistically significant effect on the change in cavity dimension, as measured by area and perimeter. The 2.5-mm-deep cavities showed greater loss of tooth structure. No statistically significant difference was found for different cavity designs or shade matching. Conclusion: Replacement of Class I resin-based composite restorations results in loss of tooth structure. The deeper the original cavity preparation, the greater the loss of tooth structure at the occlusal cavosurface margin during replacement.

Objective: The aim of this in vitro study was to assess the effect of tip diameter, nozzle distance, and application time of an air-abrasion system for cavity preparation on the enamel of primary teeth. Method and materials: Forty exfoliated primary teeth were air abraded with a microabrasion machine used with a handpiece with an 80-degree-angle nozzle, 50-µm abrasive particle size, and 80-psi air pressure. The effects of 0.38- or 0.48-mm inner tip diameter, 2- or 5-mm distance from tip to tooth surface, and 15 or 30 seconds of application time on cutting efficiency were evaluated. Cutting width and depth were analyzed and measured from scanning electron micrographs. Results: Statistical analysis revealed that the width of the cuts was significantly greater when the tip distance was increased. Significantly deeper cavities were produced by a tip with a 0.48-mm inner diameter. The application time did not influence the cuts. Conclusion: The cutting patterns found in this study suggest that precise removal of enamel in primary teeth is best accomplished when a tip with a 0.38-mm inner diameter is used at a 2-mm distance.

It has been proposed that the discrepancy between the seated and unseated condylar position be identified and eliminated when the occlusion is reorganized. Identification of this discrepancy is most accurately accomplished through the use of diagnostic casts that have been taken from a deprogrammed patient and mounted in the seated condylar position on a semiadjustable articulator through an estimated facebow transfer. The amount and direction of any discrepancy is determined three dimensionally with condylar position instrumentation.

Patients who are congenitally missing one tooth or more are frequently encountered in routine practice. The etiology, classification, and clinical features of hypodontia are reviewed, and treatment modalities are discussed. One case of mild-to-moderate hypodontia and one case of severe hypodontia are described. Osseointegrated implants have provided encouraging results, especially in patients who are missing anterior teeth or who have severe hypodontia.

This article describes a novel technique for primary anterior tooth replacement using a new prosthetic system that requires minimally invasive dental preparation. The technique was used to restore the dentition of a 42-month-old girl with extensive loss of tooth substance.

Since 1966, Dr Jerry Lowney has practiced orthodontics in Norwich, Connecticut, where he has been active in both community and professional organizations, including the University of Connecticut Board of Trustees and the Board of Governors for Higher Education. Since his first volunteer trip to Haiti in the mid-1980s, during which he provided dental services for the poor, he has returned to that country at least three times each year. Over time the nature of his activities has changed. Through grant writing, personal influence, liaison with a religious order, a huge investment of time, successful fundraising, the seizing of every opportunity, and the expenditure of large amounts of his own money, he has created a multimillion-dollar general health facility in one of the poorest areas in Haiti. Besides dental treatment, the scope of his activities has ranged from creating centers for high-risk pregnancy and malnutrition to the hiring of physicians, the training of local nurse practitioners, and an Adopt-a-Family program run by his wife, Virginia. His actions have been influenced by Virginia's caring attitudes and by his conviction that much is expected from those who have received life's bounties.