Expression of estrogen receptors in desquamative gingivitis.

BACKGROUND: Most cases of chronic desquamative gingivitis (CDG) are shown by direct immunofluorescence (DIF) to be immune mediated diseases. Some patients present with similar clinical and microscopic findings as CDG but DIF staining is negative. It has been suggested that those cases of CDG may be hormone (estrogen) mediated and may be treated with estrogens with favorable results. METHODS: Gingival tissue from 24 cases of CDG and one case of ordinary gingivitis were studied for estrogen receptor (ER) expression using immunohistochemical techniques. Twenty-four of the 25 cases were female. Using standard DIF analysis, 11 of the CDG cases were diagnosed as benign mucous membrane pemphigoid, 10 as lichen planus or lichenoid mucositis (LP), and one as pemphigus. The remaining 3 cases were not diagnostic for a specific disorder (idiopathic). Five of the females had a history of estrogen substitute therapy. RESULTS: Twenty-two of 23 female CDG cases were positive for ER, although the degree of staining varied. A 32-year-old female with ordinary gingivitis, whose gingivitis varied with her menstrual cycle, did not stain for ER. A 50-year-old male and a 76-year-old female, both with gingival LP, also had negative staining for ER. CONCLUSIONS: There appears to be no correlation between diagnosed diseases (immunological versus idiopathic) and expression of ER in CDG gingiva. ER expression in the gingiva is probably not related to the presence or absence of estrogen supplementation. The results of this study do not support the use of estrogen in the treatment of idiopathic CDG.

Histologic and clinical observations of resorbable and nonresorbable barrier membranes used in maxillary sinus graft containment.

In this study, clinical and histologic responses to a bioresorbable membrane used to obturate an osteotomy site in the lateral wall of the maxillary sinus and to facilitate graft containment were examined. Expanded polytetrafluoroethylene (e-PTFE) membranes were used as a control to compare biocompatibility and resorption characteristics. Twelve sinus augmentation procedures were performed to facilitate placement of implants in nine patients with insufficient bone in the edentulous posterior maxillae. In five procedures, the lateral wall was obturated to ensure graft containment with an e-PTFE membrane; the other seven were covered with a bioresorbable barrier (poly[lactic acid]). The presence or absence of inflammation, dehiscence, suppuration, and encleftation were recorded. All patients healed without complication or adverse biologic reaction to either barrier material. Biopsy specimens of the graft site were taken from the lateral wall with overlying soft tissue prior to reflection of the full-thickness flap at stage 2 surgery. Findings suggest that a poly(lactic acid) membrane can provide results similar to those with e-PTFE membranes for use in lateral obturation during sinus augmentation.

Association of oral spirochetes from sites of periodontal health with development of periodontitis.

The purpose of this investigation was to determine whether the presence of disease-associated bacteria in health-associated plaque correlated with susceptibility to periodontitis over time. Sites of periodontal health were identified in 65 adults. Six months later (recall 1), plaque was collected from sites that remained in periodontal health, and specific bacteria were detected using monoclonal antibodies in a microscopic assay. The spirochete morphogroup was identified by phase contrast microscopy. The relationship between detection at recall 1 and development of periodontitis over two successive 6-month intervals (recalls 2 and 3) was evaluated by means of logistic regression using generalized estimating equations (GEE), from which odds ratios (OR) were estimated and tested for significance. Significant relationships were defined as those having ORs with P < 0.05. Ninety-three of 1,032 sites developed signs of early periodontitis over the 12-month interval between recall 1 and recall 3. The spirochete morphogroup (OR = 3.13, P < 0.001) and pathogen-related oral spirochetes (PROS) (OR = 3.68, P < 0.001) were significantly associated with healthy sites that developed periodontitis. The association of Treponema socranskii was not significant (OR = 3.62, P = 0.0918). Odds ratios for Campylobacter rectus, Eikenella corrodens, and Porphyromonas gingivalis were less than 2.0 and not significant. Treponema denticola was not detected in health-associated plaque from stable health sites and was detected in only three sites that progressed to periodontitis. These findings indicate that the presence of PROS and some unidentified spirochetes in health-associated plaque is associated with increased susceptibility to periodontitis.

Marginal fidelity and microleakage of porcelain veneers made by two techniques.

This study evaluated the marginal fidelity and microleakage of porcelain veneers made with the platinum foil and refractory die techniques. Maxillary incisors, matched for size and amount of enamel, were prepared with 0.5 mm uniform intraenamel reduction. The indirectly made veneers were etched, treated with silane, and luted with a composite resin, and the margins were finished and polished. The restored teeth were stored in 37 degrees C water, thermocycled 1000 times, stained with silver nitrate, embedded, sectioned buccolingually and mesiodistally, and measured at x250 magnification. The platinum foil veneers had significantly better vertical marginal fidelity but significantly more overcontouring than had the refractory die veneers. Universal microleakage at the tooth-composite resin interface and negligible microleakage at the porcelain-composite resin interface were observed. No relationship was found between the amount of vertical marginal opening and the amount of microleakage.

In vitro microleakage of dentin adhesives.

This in vitro study measured the microleakage of current dentin bonding agents and glass-ionomer bases. Freshly extracted human molars were prepared to a flat surface, and dentin adhesives and composite resins were applied in a plastic matrix. Samples were stored in water at 37 degrees C, thermocycled, stained with AgNO3, embedded in epoxy resin, and sectioned for evaluation of stain penetration at the composite resin/tooth interface. The reliability index of the dentin adhesives varied significantly between materials. The enamel control had essentially no microleakage, and the aluminum oxalate dentin adhesive on dentin had significantly less microleakage than other dentin adhesives tested. Present dentin adhesives were unable to prevent, but may reduce, microleakage.

Porcelain-composite interface microleakage with various porcelain surface treatments.

This study evaluated the effects of various porcelain surface treatments on the microleakage of the porcelain-composite interface. The experimental model isolated and evaluated only the porcelain-composite interface without the presence of a bond to tooth structure. Four types of porcelain were fired into circular porcelain tabs 1.0 mm thick by 8.5 mm in diameter. The groups of porcelain were divided into subgroups for treatment with hydrofluoric acid-etching and silane. A jig standardizing composite thickness to 0.2 mm was used to photopolymerize composite to porcelain. The margins were finished and polished with burs and disks. Samples were stored in 37 degrees C water thermocycled 1000X, placed in AgNO3 solution, embedded in epoxy, and cross-sectioned every 90 degrees for measurement of stain penetration at the composite-porcelain interface. Occasional crazing of porcelain from composite polymerization shrinkage was observed. Porcelain surface treatment significantly increased the specimens' ability to withstand water storage and thermal-cycling procedures. Porcelain surface treatment with silane alone did not reduce microleakage, but, in combination with etching, reduced microleakage significantly.

Shear bond strength of composite resin to porcelain.

This study evaluated the effect of porcelain surface treatment on the shear bond strength of composite resin to various porcelains and porcelain combinations. A variety of feldspathic porcelains with low and medium alumina content were tested. Porcelain/composite resin samples were stored in 37 degrees C water, thermocycled 1,000 times, and tested in shear. A 3-minute etching using hydrofluoric acid significantly increased the bond strength of most of the feldspathic porcelains with low and medium alumina content. Silane application to all types of etched porcelain had no significant effect on bond strength.