Quintessence International, 02/1996

Restitution of the complex central sulcular portion of teeth is extremely difficult when direct tooth-colored restorative materials are used, because sculpturing of the solid polymerized mass is accomplished mechanically with burs. When the initial carious lesion presents within a shell of undermined yet intact enamel, the preoperative occlusal morphology provides an ideal index of the esthetic and functional anatomy. The preoperative occlusal morphology is recorded in a transparent registration material, and then the registration is used as an index to reproduce the preoperative occlusal morphology in the final incremental restorative layer. Photopolymerization of the restoration is initiated through the translucent index and completed with surface approximation of the light source once the index has been removed.

The most common oral opportunistic infection affecting persons with acquired immunodeficiency is candidiasis. This article reports on candidal infection of the tongue together with candidal infection of the palate in patients who have the human immunodeficiency virus. A retrospective analysis of 336 patients with acquired immunodeficiency syndrom revealed a prevalence of 8% with candidal infection of both the tongue and palate. Patients in this group were significantly older (39.2 years versus 34.5 years) and had significantly lower CD4-CD8 ratios than did the rest of the cohort.

This in vitro study compared physical properties of root canal posts made of carbon fiber-reinforced epoxy resin with those of stainless steel posts. Three-point bending tests were used to derive the transverse modulus of elasticity of the posts. Resin composite cores on the posts were subjected to tensile forces to test the bonds between the cores and posts. Carbon fiber posts appeared to have adequate rigidity for their designed purpose. The bond strength of the resin composite cores to the carbon fiber posts was significantly less than that to the stainless steel posts.

The aim of this study was to clinically evaluate fluoride-containing sealants in teeth subjected to minimal enamel reduction (preventive resin restorations). Two hundred fourteen sealants (109 FluroShield and 105 Delton Fluor) were applied in 153 teeth of 32 subjects. The sealants were evaluated for superficial irregularities, marginal adaptation, retention, and caries after 6, 12, 18, and 24 months. After 6, 12, and 18 months, the attendance at recall was 100.00%. After 24 months, 93.75% of subjects returned for reevaluation. Although total or partial loss of sealant occurred in a few instances, no occlusal caries was found in any tooth at any recall. No statistically significant differences in the results of the clinical evaluation were found between sealant in the maxillary and mandibular dentitions.

A woman presented with temporomandibular dysfunction caused by a marked overclosure of her mandible. She complained of pain and clicking noises in her temporomandibular joint. After initial assessment and treatment with a provisional occlusal acrylic resin splint, the patient was provided with a definitive overlay denture with visible light-cured resin as occlusal overlays. The denture was stable in the mouth and the occlusal resin material showed some occlusal wear at the 2-year examination.

Multiple mandibular canals of the bifid variety characterized by a single foramen and two nearly equal canals are unusual (occurrence less than 1%) but not rare. A more unusual case, the occurrence of two separate canals, has been mentioned only twice in the literature, once without documentation. An example of this condition has been found on a routine preoperative radiograph, and no other published examples of this condition could be found in a review of the literature. This case serves as a reminder that multiple canals do occur with some regularity.

This investigation assessed the effect of variations in preparation on fracture resistance of teeth restored with all-ceramic crowns placed with a resin composite luting material after the dentinal surface had been treated with a dentinal bonding system. Four groups of 10 sound, unrestored, maxillary premolars were prepared. In group A, minimal preparations of 6-degree taper, 2-mm occlusal reduction, and a kinfe-edged margin were carried out. Preparations in group B received 6-degree taper, 3-mm occlusal reduction, and a 1-mm shoulder. Preparations in group C were as in group B, but with 2-mm occlusal reduction over buccal cusp and minimal cervical preparation buccally. Preparations in group D were as in group B, but with 2-mm occlusal reduction. The restored teeth were subjected to compressive loading. Mean fracture loads of 0.77 kN, 0.99 kN, 0.91 kN, and 0.78 kN were recorded for groups A, B, C, and D, respectively. Statistical analysis failed to reveal any difference among the groups.

Bulimia nervosa, an increasingly common eating disorder, involves binge eating and subsequent purging behavior. Repeated self-induced vomiting may lead to dental erosion. This article describes the use of resin-bonded ceramic crowns to manage a severely eroded maxillary dentition in such a patient.

Calcium hydroxide has been used as a liner in resin composite restorations to protect the pulp. Recent research has demonstrated that pulpal inflammation is caused by microleakage of restorations and by the subsequent passage of bacteria. The present study involved scanning electron microscopic observation of cross-sections of resin composite-dentin interfaces after the interposition of a layer of calcium hydroxide. A new-generation adhesive system that involves etching of the dentin was used. Ultrastructural analysis indicated that polymerization shrinkage of the resin composite caused the separation of the calcium hydroxide from the dentinal surface, forming 8- to 15-um-wide interfacial gaps in 100% of the areas studied. Where the adhesive was applied directly to dentin, it adhered closely, forming a gap-free attachment with evidence of an acid-resistant hybrid layer (4 to 6 um in thickness) and resin tags of various lengths that hermetically sealed the dentinal tubules.