Posterior Restoration Selection Among General Dental Practices in Malaysia: A Preliminary Study

@#Introduction: Tooth restoration is a common, routine procedure among dentists but still has its own difficulties especially for posterior teeth. As it is a straightforward procedure, some dentists are not aware of the difficulties that may contribute in reducing the longevity of the filling. The aim of the study is to determine the difficulties encountered during and after placement of restorative materials in deep cavities. Materials and methods: Standardized questionnaires were divided randomly among general private dental practitioners in Kuala Lumpur. Chi-square test was used to determine any significant factors associated with difficulties of material placement. Results: This study showed that the most frequent difficulties encountered among practitioners were to obtain good moisture control (39.0%). No significant association was found between obtaining good moisture control and year of clinical experience (p= 0.286) and also place of graduation with the manipulation of the materials (p= 0.542). Conclusion: Dental practitioners claimed that it was difficult to obtain good moisture control in placement of posterior restoration. Thus, it is an obligation of dental practitioners to practice proper isolation and good manipulation of materials on posterior restoration.

Rehabilitating Form, Function and Natural Aesthetics with Onlay Ceramic IPS Empress Esthetic®: Evidence and Versatility / Rehabilitando forma, función y estética mediante el uso de un Onlay IPS Empress Esthetic®: Evidencia y Versatilidad

Abstract Clinical research and in vitro laboratory tests have enabled the development and improvement of dental ceramics. Comprehension of the physical and mechanical properties of this material is essential, in order to ensure a functional, aesthetic and long-lasting posterior ceramic restoration. The clinical protocol for onlay preparation involves important considerations in treatment planning, such as selection of the restorative material, biomechanical design, color selection, dental substrates conditioning and adhesive cementation. This article discusses a brief review on the topic and a case presentation in which a posterior tooth was rehabilitated with an IPS Empress Esthetic® ceramic onlay.

Resumen La investigación clínica y las pruebas de laboratorio in vitro han permitido el desarrollo de los materiales cerámicos en odontología. La comprensión de las propiedades físicas y mecánicas de este material es esencial para asegurar una restauración funcional, estética y duradera. El protocolo clínico para la preparación de un onlay implica consideraciones importantes en la planificación del tratamiento, tales como la selección del material restaurador, diseño biomecánico, selección de color, acondicionamiento de sustratos dentales y cementación adhesiva. Este artículo discute una breve revisión sobre el tema y una presentación de caso en la que un diente posterior fue rehabilitado con una restauración indirecta tipo Onlay.

Irradiance and radiant exposures delivered by led light-curing units used by a left and right-handed operator

Abstract The combination of the restoration location, the hand preference of the operator using the light-curing unit (LCU), and the design of the LCU all can have an impact on the amount of the light delivered to the restoration. To evaluate the effect of left-handed or right-handed users, the position of the operator (dentist or assistant), and the LCU design on the irradiance, radiant exposure and emission spectrum delivered to the same posterior tooth. Two light emitting diode (LED) LCUs were tested: an angulated monowave LCU Radii-Cal (SDI, Victoria, Australia) and a straight aligned multi-peak LCU Valo Cordless (Ultradent, South Jordan, UT, USA). The irradiance values (mW/cm2), radiant exposure (J/cm2) and emission spectrum were measured using a sensor in maxillary left second molar tooth. The irradiance and radiant exposure were analyzed using three-way ANOVA followed by Tukey test (a=0.05). The emission spectra (nm) were analyzed descriptively. The interaction between LCU design, operator position, and hand preference significantly influenced the irradiance and radiant exposure (P<0.001). In all cases, Valo delivered significantly higher irradiance than Radii-Cal. The handedness and the operator position affected the irradiance and radiant exposure delivered from Valo. Operator position and access affect the irradiance and radiant exposure delivered to the maxillary left second molar. The irradiance and radiant exposure can be greater when a right-hand operator is positioned on the right side of the chair and a left-hand operator is positioned on the left side of the chair. This may result in better resin composite polymerization.

Resumo A combinação da localização da restauração, a preferência de mão do operador ao utilizar aparelhos fotopolimerizadores (AFP) com luz emitida por diodo (LED) e o formato do AFP podem afetar a quantidade de luz fornecida à restauração. O objetivo foi avaliar o efeito de operadores canhotos e destros, a posição do operador (dentista ou auxiliar), e o formato do AFP na irradiância, energia radiante e espectro de luz entregue ao mesmo dente posterior. Dois AFP foram testados: um com formato angulado, onda única Radii-Cal (SDI, Victoria, Australia) e um formato reto multi-pico Valo Cordless (Ultradent, South Jordan, UT, USA). Os valores de irradiância (mW/cm²), energia radiante (J/cm²) e espectro de luz foram medidos utilizando um sensor no segundo molar superior esquerdo. A irradiância e energia radiante foram analisados utilizando ANOVA 3 fatores seguido por teste de Tukey (a=0.05). O espectro de luz (nm) foi analisado de forma descritiva. A interação entre o formato do AFP, posição do operador e preferência de mão foram significativamente influentes na irradiância e energia radiante (P<0.001). Em todos os casos, Valo teve irradiância significativamente maior que Radii-Cal. A mão dominante e a posição do operador afetaram a irradiância e energia radiante com o Valo. Posição do operador e acesso afetou a irradiância e exposição radiante entregue ao segundo molar superior esquerdo. A irradiância e exposição radiante teve melhores resultados quando AFP foi utilizado com a mão direita pelo operador posicionado na cadeira do lado direito e mão esquerda do operador posicionado do lado esquerdo da cadeira. Estes resultados podem levar a uma melhor polimerização da resina composta.

Restoration of posterior teeth using occlusal matrix technique.

This article describes a technique for duplicating occlusal surface anatomy using the Biteperf device. Duplication requires an intact occlusal enamel surface and is only indicated when caries lesions are hidden. The occlusal matrix technique allows for preservation of all anatomic details. When the last layer of composite has been placed, the occlusal matrix is forced into the uncured composite to replicate the original occlusal surface, instead of performing manual curing and shaping as in the standard approach. It is technically possible to achieve this effect with any material that is able to copy anatomic details. The main benefits of the occlusal matrix technique, more precisely the Biteperf, are the technical ease of use due to its simplicity and its high accuracy in reconstructing occlusal morphology.

Influencia del biselado de los márgenes cavo-superficiales en la desadaptación marginal mostrada por restauraciones posteriores de composite / Influence of beveling cavo-surface margins in maladjustment shown by marginal posterior restorations of composite

Las fallas marginales representan una de las causas más frecuentes de fracaso en las restauraciones de composite en el sector posterior. Los niveles de falla marginal presentados por estas restauraciones podrían verse afectados por el tipo de configuración dado a los márgenes cavo-superficiales; no obstante, la información disponible al respecto tiende a ser contradictoria. Determinar la influencia que tiene el diseño de tres tipos de márgenes cavo-superficiales (unión abrupta, bisel corto y bisel cóncavo) en los niveles de deterioro marginal presentados en restauraciones directas de composite realizadas en dientes posteriores sometidos a cargas compresivas. Sesenta dientes posteriores humanos sanos extraídos (30 premolares superiores y 30 terceros molares superiores) fueron distribuidos aleatoriamente en tres grupos, cada uno de los cuales estuvo conformado por 10 premolares y 10 molares. A cada uno de los dientes le fue realizada una cavidad clase I estándar con una configuración distinta de margen cavo-superficial para cada grupo (grupo 1= unión abrupta, grupo 2= bisel corto, grupo 3= bisel cóncavo), para posteriormente ser restaurados con un composite empacable mediante técnica directa. Todos los dientes fueron sometidos a 1500 ciclos térmicos entre 5 y 55ºC para posteriormente aplicarles 4000 ciclos de cargas compresivas cíclicas de 300 kN de fuerza máxima a una frecuencia de 5 Hz. El análisis en video lupa de las superficies oclusales de la muestra no reveló diferencias estadísticas significativas (p= 0,139) en los niveles de falla marginal mostrados por los tres tipos de margen cavo estudiados

Marginal deterioration is one the most frequent composite restoration failures at posterior teeth with chewing function. The type of configuration factor at cavosurface margins could affect marginal deterioration levels; however, available information is somewhat contradictory. To determine the influence of three cavosurface margin preparations (butt-joint, bevelled-edge, and concave bevel -chamfer style-) on marginal degradation found in direct composite restorations applied to posterior teeth under compressive strength. Sixty recently extracted human posterior teeth (30 upper bicuspid teeth and 30 upper third molars) were randomly distributed into three groups, having 10 bicuspid teeth and 10 molar teeth each group. Each tooth had standardized Class I slot cavities and was prepared according to the cavosurface margin preparations above mentioned (group 1=butt-joint, group2=bevelled-edge, group 3=concave bevel); then, it received direct packable composite restoration. All teeth were thermocycled 1500x at 5/55 degrees C, cycled 4000x of compressive loading at a maximum strength of 300kN and a frequency of 5Hz. Video loupe analyses of occlusal surfaces from the study sample did not show statistically significant differences (p=0.139) among the three cavosurface margin preparations studied