RESUMEN
OBJECTIVE: To compare the clinical performance of a pit and fissure sealant placed with the use of different enamel preparation methods, i.e. acid or Er,Cr:YSGG laser etching, over 24 months. METHODS: Sixteen subjects (15 female, 1 male) with no restorations or sealant present on their fissures and no detectable caries participated. Using a table of random numbers, a total of 112 sealants (56 with acid-etching, 56 with laser etching) were placed on the permanent premolar and molar teeth. All restorative procedures except for application of the laser were performed by the same dentist. After completion of the fissure preparation either with acid or laser, the adhesive was applied; then a pit and fissure sealant, Clinpro Sealant, was placed and polymerized. Clinical evaluations were done at baseline and at 6-, 12-, 18-, and 24-month follow-up visits by two calibrated examiners, who were unaware of which etching method had been used. The retention of sealants and caries were evaluated with the aid of a dental explorer and an intra-oral mirror. Each sealant was evaluated using the following criteria: 1=completely retained; 2= partial loss; 3= total loss. The Pearson chi-square test was used to evaluate differences in the retention rates among the sealants used with different etching methods. RESULTS: All patients attended the 24-month follow-up visit and all sealants were evaluated (total recall rate 100%). At the end of 24 months, 83.9% of the sealants from laser group and 85.7% of those from acid-etch group were recorded as "completely retained". There were no statistically significant differences in retention rates among the preparation methods after all evaluation periods (p>0.05). No statistically significant differences were found between the retention rates of premolar and molars at each evaluation period. No secondary caries was detected in association with any sealants. CONCLUSION: The clinical performance of fissure sealants placed after acid or Er,Cr:YSGG laser etching was similar.
Asunto(s)
Grabado Ácido Dental/métodos , Grabado Dental/métodos , Láseres de Estado Sólido , Selladores de Fosas y Fisuras/química , Diente Premolar/anatomía & histología , Diente Premolar/efectos de los fármacos , Diente Premolar/efectos de la radiación , Resinas Compuestas/química , Luces de Curación Dental , Recubrimiento Dental Adhesivo , Cementos Dentales/química , Esmalte Dental/anatomía & histología , Esmalte Dental/efectos de los fármacos , Esmalte Dental/efectos de la radiación , Pulido Dental/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Diente Molar/anatomía & histología , Diente Molar/efectos de los fármacos , Diente Molar/efectos de la radiación , Ácidos Fosfóricos/química , Propiedades de Superficie , Preparación del Diente/métodos , Resultado del Tratamiento , Adulto JovenRESUMEN
This study evaluated fracture resistance in class II slot packable composite restorations with and without the use of a flowable composite liner. A conventional microhybrid composite was used as a control. Thirty-six sound, caries-free human mandibulary molar teeth were used. Separate mesio-occlusal and disto-occlusal class II slot cavity preparations were made in each tooth. The prepared teeth were randomly divided into three groups of 12 teeth. Two packable composites (Surefil, Filtek P60) and one microhybrid composite (Filtek Z250) with their respective manufacturer's bonding agents were used to restore the cavities. One side of each tooth was restored with composite alone, while the other side was restored with the composite lined with that manufacturer's flowable liner. The marginal ridges of the restorations were loaded at an angle of 13.5 degrees to the long-axis of the tooth in an Instron Testing Machine until failure. The data were analysed using a one-way anova. There was no significant difference in fracture resistance between composite restorations with and without flowable liners.
Asunto(s)
Resinas Compuestas , Restauración Dental Permanente/métodos , Bisfenol A Glicidil Metacrilato , Análisis del Estrés Dental/métodos , Recubrimientos Dentinarios , Humanos , Mandíbula , Ensayo de Materiales/métodos , Diente Molar , Ácidos PolimetacrílicosRESUMEN
The purpose of this study was to evaluate the effect of various finishing and polishing procedures on the surface roughness of three new tooth-coloured restorative materials. The materials included a hybrid composite resin (Filtek Z250), a packable composite resin (Filtek P60), and an ormocer (organically modified ceramic) (Definite). Thirty-two specimens of each material were prepared and randomly divided into four finishing and polishing groups (n = 8): (i) diamond bur/silicone polishers, (ii) diamond bur/Sof-Lex discs, (iii) carbide bur/silicone polishers, (iv) carbide bur/Sof-Lex discs. Average surface roughness (Ra) in micrometers was measured with a Mitutoyo Surftest-402 Surface Roughness Tester and the data compared using anova, at P < or = 0.05. Surface topography was also assessed using the scanning electron microscope (s.e.m) from samples of each group. The Mylar strip produced the smoothest surface and finishing/polishing procedures; (ii) and (iv) were significantly smoother than (i) and (iii). The lowest variability in initial surface roughness between materials was also observed with ormocer group.
Asunto(s)
Pulido Dental , Restauración Dental Permanente , Resinas Compuestas , Microscopía Electrónica de Rastreo , Coloración de Prótesis , Propiedades de SuperficieRESUMEN
PURPOSE: This study evaluated the effects of three preparation designs and the influence of an adhesive system in Class II amalgam restorations when a load was applied directly to the marginal ridge. MATERIAL AND METHODS: Seventy-two sound caries-free maxillary molars were divided into 6 groups of 12 teeth. In groups 1 and 4, the preparation had an extension through the occlusal groove, whereas the other four groups used a proximal slot (box-only) preparation. Groups 2 and 5 had facial and lingual retention grooves that extended from the gingival floor to the occlusal surface, and groups 3 and 6 had slots without grooves. Teeth in groups 1, 2, and 3 were restored with amalgam and groups 4, 5, and 6 were restored with resin bonded amalgam. The marginal ridges of the restorations were loaded at an angle of 13.5 degrees to the long axis of the tooth in an Instron testing machine until failure. RESULTS: Analysis of mean failure loads indicated that proximal slot preparations with retention grooves or occlusal extensions were statistically equivalent but significantly greater than proximal slots without grooves. The addition of an adhesive system improved fracture values for all three types of preparations. CONCLUSIONS: When proximal caries was diagnosed and no occlusal caries was evident, a proximal slot amalgam restoration combined with retention grooves and an adhesive system was the appropriate choice.