Quintessence International, 01/1997

Anterior palatal tooth wear is easily recognized, but its precise pathogenesis remains unknown. Treatment of this condition with cast-alloy palatal veneers used in combination with an adhesive cement is described. Forty-eight patients, aged 11 to 71, were treated with a total of 210 cast metal veneers over a period of 56 months. Twenty-three of the restorations failed, resulting in an overall success rate of 89%. All failures were confined to 13 patients. A glass polyalkenoate cement was less effective than a chemically active resin composite luting agent. Nickel-chromium veneers cemented with activated resin composite recorded a survival pobability of 0.74 at 56 months. Adhesive cast-alloy veneers provied a useful method of restoring maxillary anterior teeth affected by acid erosion.

Children suffering from the inherited dental anomaly amelogenesis imperfecta frequently present with sensitive, discolored teeth and decreased lower facial height. The aim of treatment is to reduce sensitivity while maintaining the maximum amount of hard tissue possible until the patient reaches an age at which advanced restorative techniques can be used to rehabilitate the dentition. A case is presented in which amelogenesis imperfecta in the mixed dentition was managed by the placement of adhesive cast restorations. These restorations have been in place for 2 years.

Many dentists routinely make panoramic radiographs of edentulous patients who request replacement dentures. A study was conducted in patients who attended a Jordanian dental school seeking a new set of dentures. Patients who had at least one set of complete dentures and were treated elsewhere, were included in this study. Any patient whose clinical findings suggested a need for further radiographic study was excluded. Of 286 patients (572 edentulous arches), only three were found to have impacted molars that required extraction and altered the treatment plan. The use of radiography in dentistry generates a large expense and there are risks of radiation hazards. The routine use of radiographs for patients who wear complete dentures and need replacement dentures should be discouraged. A thorough history must be obtained and a careful clinical examination must be performed for the diagnosis and treatment planning.

Several caries activity tests were used to investigate the caries risk of patients with Fixed orthodontic appliances. Twenty young individuals, with a mean age of 11 years, participated in this study. Ten subjects were free of any orthodontic appliances and formed the control group. The other 10 individuals had been wearing fixed orthodontic appliances for at least 4 months. Stimulated saliva samples were obtained from all patients. Saliva samples were used to investigate the salivary flow rate, the salivary buffer capacity, and mutans streptococci and lactobac illi counts. The orthodontic patients exhibited a significant increase in salivary flow rate. Results of statistical analyses were nonsignficant in all other tests, suggesting that fixed orthodontic appliances are not the sole factor increasing the patient's caries risk during orthodontic treatment.

Subcutaneous emphysema can occur whenever compressed air is employed intraorally. A case is presented of subcutaneous, orbital, and mediastinal emphysema subsequent to the use of an air-abrasive device. The case is believed to be the first reported case of an air-abrasive-r elated emphysema and is presented as a cautionary report.

The clinical usefulness of continuous E-glass partial fiber reinforcement of acrylic resin removable dentures was evaluated an average 13 months after the insertion of the fibers. Twelve removable complete dentuers and ten removable partial dentures with a history of recurrent fracture were selected for this study. The partial fiber reinforcement was incorporated into the denture at the time of repair. One complete denture and one removable partial denture fractured in the region of reinforcement during the examination period. These fractures were most likely caused by faulty placement of the fiber reinforcement in the denture in the dental laboratory. In six dentures, new fractures occurred in regions without partial fiber reinforcement. The results revealed the importance of both the correct positioning of the partial fiber reinforcement in the denture and the use of accurate laboratory techniques.

The dentinogenic ghost-cell tumor is a rare solid variant of t he calcifying odontogenic cyst. Few peripheral cases of this tumor with clinical and radiographic documentation have been reported. A case of peripheral dentinogenic ghost-cell tumor is presented and the literature is reviewed

Previous studies have indicated that adhesive liners can affect the mechanical properties of set amalgam and, therefore, may become incorporated within the amalgam. The purpose of this in vitro study was to determine the distribution of two adhesive liners within standardized Class I amalgam restorations. Cavity preparations were restored with dental amalgam or with dental amalgam and either of two adhesive liners. Thin sections were cut from the restored teeth in various planes and examined radiographically and with a reflecting microscioe. Radiographs were digitized and computer enhanced for improved observation. Amalgam restorations placed with adhesive liner had greater amounts of nonadmalgam substance t han did the nonadhesive liner restorations. Both Amalgambond Plus and Resinomer used with All-Bond II were capable of becoming incorporated within the body of a Class I restoration placed with a standard restorative amalgam bonding technique.

This study examined the influence of eugenol on the dentinal adhesion of an enamel-dentin bonding agent that removes the smear layer (total-etch technique) and a system that partially dissolves the smear layer (self-conditioning adhesive system). The tensile bond strength was measured on flat, dentinal surfaces after application and removal of pure eugenol for 15 minutes and a eugenol-containing temporary luting agent for 24 hours. In addition, the resin-dentin interface was evaluated with confocal laser scanning microscopy. Dentinal adhesion was found to be significantly reduced after the application of eugenol when a dentin bonding agent that dissolves the smear layer was used. Underconfocal laser scanning microscopy, the resin-dentin interdiffusion zone of both adhesives was found to be changed, not only after application of eugenol but also after application of a eugenol-containing temporary luting agent.

This report describes a method of immobilizing the water contained in glass-ionomer cement and dental hard tissues and stabilizing the delicate organic component of dentin. With this method, the intact interface between glass-ionomer and dental hard tissues can be observed under scanning electron microscope with few of the artifacts that are caused by the desiccation associated with conventional scanning electron microscopic studies. There was a distinct zone of interaction between the glass-ionomer cement and enamel and dentin. Under severe thermal stress, glas-ionomer cement failed cohesively, leaving an intact interface with enamel and dentin. Machine-mixed glass-ionomer cements displayed a high level of porosity. Some glass particles were separated from the matrix, and there was evidence that some are dislodged from the matrix during specimen preparation.