RESUMEN
This study sought to compare and rank the in vitro microleakage behavior of four self-etching adhesive systems to determine any differences in their marginal sealing ability. Using a coarse rounded diamond wheel, Class V cavities were prepared at the facial or lingual cementoenamel junction (CEJ) of 40 recently extracted human third molars. All preparations had incisal margins in enamel and gingival margins in dentin. Ten randomly selected teeth were restored with one of four different adhesive systems; all teeth received the same composite material. The teeth were stored in distilled water (37 degrees C) for four weeks, thermocycled between 4 degrees C and 58 degrees C for 100 cycles, treated with 45Ca radioisotope, sectioned, and placed on radiographic film to produce autoradiographs. The degree of microleakage was scored separately at the enamel (incisal) and dentin (gingival) margins, and the results were compared using nonparametric statistical methods. The analysis found statistically significant differences in the degree of microleakage between the materials used at both the dentin and enamel margins.
Asunto(s)
Grabado Ácido Dental/métodos , Resinas Compuestas/química , Caries Dental/terapia , Filtración Dental/prevención & control , Restauración Dental Permanente/métodos , Recubrimientos Dentinarios/química , Resinas Acrílicas/química , Resinas Acrílicas/uso terapéutico , Resinas Compuestas/uso terapéutico , Recubrimiento Dental Adhesivo/métodos , Esmalte Dental/efectos de los fármacos , Adaptación Marginal Dental , Recubrimientos Dentinarios/uso terapéutico , Humanos , Metacrilatos/química , Metacrilatos/uso terapéutico , Cementos de Resina/química , Cementos de Resina/uso terapéuticoRESUMEN
For various reasons, dentists may be tempted to definitively tighten implant abutment screws using only handheld screwdrivers. The purpose of this study was to test the ability of general dentists to generate implant abutment screw preload using a simple screwdriver in a limited-access space simulating the mouth. Results indicated that mechanical torque wrenches must be used in posterior areas of the mouth to establish sufficient preload, and dental experience is not a major factor in the ability to tighten an implant abutment screw.