Three-Year Effects of Deproteinization on the In Vitro Durability of Resin/Dentin-Eroded Interfaces.

OBJECTIVE: To evaluate the effect of sodium hypochlorite on the immediate and three-year bonding properties of a resin-eroded dentin interface produced by one of two adhesive strategies. METHODS AND MATERIALS: Forty-eight molars were randomly assigned to six experimental groups, according to the combination of the adhesive strategy (etch-and-rinse and self-etch) and the dentin surface (control groups without erosion, eroded dentin surface [ED], and eroded dentin surface + NaOCl 5.2% [ED + NaOCl]). After completing restoration, specimens were stored in water (37°C) for 24 hours and then sectioned into resin-dentin beams (0.8 mm2) to be tested under tension (0.5 mm/min) immediately thereafter or after three years of water storage. To assess nanoleakage (NL), specimens were immersed in silver nitrate solution and examined by scanning electron microscopy at both time points. The dentin-etching pattern was examined under a scanning electron microscope. Data were subjected to appropriate statistical analysis (α=0.05) Results: In both strategies, a more pronounced and significant reduction of the microtensile bond strength (µTBS) values was observed for the ED groups ( p=0.0001) after three years. However, in the ED + NaOCl group, µTBS values were maintained after three years of water storage. Furthermore, application of NaOCl to eroded dentin significantly reduced the immediate NL values and also preserved these values after three years of water storage for both adhesive strategies ( p>0.05). When considering the ED group, a superficial removal of the smear layer and enlarged lumen tubules in comparison to control were present. However, for ED + NaOCl, there was a total removal of the smear layer and significant numbers of collagen fibrils were exposed. CONCLUSION: The use of NaOCl may maintain the long-term stability of a resin-eroded dentin interface formed by etch-and-rinse and self-etch adhesives.

Using CAD/CAM-Modified Correlation Mode to Produce Laminate Veneers: A Six-Month Case Report.

The expectation of an esthetically harmonious smile increases the level of difficulty when treating patients. Laminate veneers stand out as a treatment option for cosmetic rehabilitation in clinical practice, as they are a more conservative procedure and mimic dental structures. These laminate veneers are generally made with different techniques; the most common requires an impression of the prepared tooth, an impression antagonist, fabrication models, and extensive laboratory time. The computer-aided design/computer-aided manufacturing (CAD/CAM) system optimizes the fabrication of prosthetic structures, reducing chairside time and promoting good esthetic results. Thus, the purpose of this case report is to present the esthetic result of multiple CAD/CAM manufactured laminate veneers using a new self-etching glass ceramic primer with a lithium disilicate ceramic, using the modified correlation and biogeneric modes.

Randomized Double-blind Clinical Trial of Bleaching Products in Patients Wearing Orthodontic Devices.

OBJECTIVES: This double-blind randomized clinical trial evaluated tooth sensitivity (TS) and the effectiveness (EF) of two types of bleaching agents (Trèswhite Ortho [TWO] and Trèswhite Supreme [TWS]) when used in patients wearing orthodontic appliances. METHODS AND MATERIALS: Forty patients between the ages of 18 and 40 years were randomly stratified, with an equal allocation rate, into two groups (n=20), according to the bleaching agent applied. Tooth color of the six maxillary anterior teeth was measured before and after the treatment with a spectrophotometer. The TS was recorded on three scales before and during the bleaching treatment. RESULTS: With regard to EF, a significant reduction was found (ranging from 7.3-9.6 and 5.3-9.5 Vita scale units for TWO and TWS, respectively, p<0.001); however, there was no statistical difference between the groups (p>0.63). The number of patients with sensitivity was 58.8% and 73.3% for TWO and TWS groups, respectively (p=0.53); however, with each of the three scales used, the intensity of sensitivity was low and there was no statistical difference between TWO and TWS (p>0.05). CONCLUSIONS: In spite of producing a side effect of low TS, the two bleaching treatments tested were effective for dental bleaching in patients with fixed orthodontic appliances.

Reparación de perforación de furca utilizando agregado de trióxido mineral (MTA)

Existe evidencia que demuestra la eficacia del agregado de trioxido mineral para reparar satisfactoriamente perforaciones de furca. Se presentan dos casos clínicos con lesión por perforación accidental radicular durante el tratamiento endodóntico. Estas lesiones fueron tratadas con MTA, siendo evaluados después de 6 meses y 1 año.

Polimerización de un cemento de composite a través de restauraciones de cerómero utilizando lámparas halógenas y LEDs / Polymerization of dual-cure resin luting cements through laboratoryprocessed- resins: LED versus halogen lights

Este estudio evaluó la influencia del grosor de una restauración indirecta de cerómero, el tipo de lámpara fotoactivadora y el tiempo de almacenamiento en la dureza Vickers de un cemento de composite. Dos lámparas de diodos (Optilight CL [CL] y Ultra-Lume 5 [UL]) fueron comparadas con la lámpara halógena (Optilux401 [OH]). Fueron confeccionados especímenes en cerómero con un diámetro de 5 mm y una espesura de 1y 2 mm, los cuales fueron interpuestos entre la luz y la matriz metálica de 5 mm de ancho y 0,5 mm de grosor que contenía el cemento de composite. Los 45 cuerpos de prueba fueron divididos en 9 grupos: G1: exposición directa de luz DLE/OH; G2: 1 mm/OH; G3: 2 mm/OH; G4: DLE/CL; G5: 1 mm/CL; G6: 2 mm/CL; G7:DLE/UL; G8: 1 mm/UL y G9: 2 mm/UL. La foto activación fue realizada durante 60 segundos. La dureza Vickers (50 g/30s) fue medida en la superficie tope de todos los especímenes luego de 24 horas y 180 días de almacenamiento. La lámpara fotoactivadora y el grosor del cerómero fueron estadísticamente significativas (p<0,05). La lámpara CL produjo los menores valores de dureza, no hubo diferencias significativas entre OHy UL. El tiempo de almacenamiento no fue significativo. Concluyendo que el grosor del cerómero y la lámpara fotoactivadora pueden influenciar la dureza superficial del cemento de composite (AU)

This study evaluated the influence of indirect composite resin thickness, the storage time and light-curing units on the Vickers hardness of a dual-cure resin luting cement. Two light-emitting diodes lights (Optilight CL [CL]and UltraLume5 [UL]) were compared with a quartz tungsten halogen unit (Optilux 401 [OH]). Laboratory processed composite specimens with a diameter of 5mm and thickness of 1 and 2 mm were constructed to be interposed between the light guide and the metal matrix (5mm wide and 0.5 mm deep) with the resin lutingcement. Then, 45 dual-cure resin luting specimens were divided in nine groups: G1: direct light exposure DLE/OH; G2: 1 mm/OH; G3: 2 mm/OH; G4: DLE/CL; G5: 1 mm/CL; G6: 2 mm/CL; G7: DLE/UL; G8: 1 mm/UL andG9: 2 mm/UL. The light curing was performed for 60 seconds. The Vickers hardness (50g/30s) was measured at the top surface of all specimens, either after 24 hours or 180 days. The Light-curing unit and the Composite thickness were statistically significant (p<0.05). The CL light curing unit produced the lowest mean hardness values; no significant difference was observed between OH and UL. No significant effect of storage time was polimerizaobserved. The thickness of the laboratory-processed resin and the light curing unit can influence the hardness of the resin luting cement (AU)