Effect of Different Laser Treatments on the Bond Strength of Intracanal Fiber Posts Cemented with a Self-Adhesive Resin Cement.

PURPOSE: To evaluate the influence of laser-activated irrigation by Er:YAG and Er:YSGG (LAI) protocols and Nd:YAG laser irradiation on the bond strength of self-adhesively cemented fiber posts to root canal dentine. MATERIALS AND METHODS: The study sample consisted of 84 human single-rooted permanent teeth instrumented with ProTaper Next technique. After obturation, post space preparations were created for fiber-reinforced composite posts. The prepared specimens were divided according to the laser treatment of the post space preparations: group 1: LAI (Er:YAG) + saline solution (pulse energy: 20 mJ, repetition rate: 15 Hz); group 2: LAI (Er:YAG) + QMiX solution (pulse energy: 20 mJ, repetition rate: 15 Hz); group 3: LAI (Er,Cr:YSGG) + saline solution (pulse energy: 62.5 mJ, 20 Hz); group 4: LAI (Er,Cr:YSGG) + QMiX (pulse energy: 62.5 mJ, 20 Hz); Nd:YAG laser (pulse energy: 100 mJ, 10 Hz). Fiber-reinforced posts were cemented with a self-adhesive cement. The bond strength was evaluated by the push-out bond strength test, and the mode of failure was determined under a stereomicroscope. Kruskal-Wallis test was used for the intergroup comparative analysis with 5% level of significance. RESULTS: The highest bond strength was recorded in the Er:YAG + QMiX group (mean 3.401 MPa) (p < 0.05), followed by the Er,Cr:YSGG and the Er:YAG + saline solution (mean 1.111 MPa and 1.094 MPa, respectively), which did not differ significantly (p = 0.232). The irradiation with the Nd:YAG laser caused similar bond strength as the Er,Cr:YSGG + QMiX (p = 0.942). CONCLUSION: All laser protocols enhanced the bond strength of the self-adhesive cement in root canals compared to only saline irrigation. The bond strength of the self-adhesive cement depended on the laser parameters and irrigant used for the LAI.

Systematic review on highly viscous glass-ionomer cement/resin coating restorations (Part II): Do they merge Minamata Convention and minimum intervention dentistry?

BACKGROUND: With the Minamata Convention the use of mercury will be phased down, and this undoubtedly will have an effect on dental treatment regimens and economic resources. Composite resin restorations are considered viable alternatives to amalgam fillings; however, these will not be covered completely by health insurance systems in many countries. Recently, a high-viscosity glass-ionomer cement (hvGIC) processed with a resinous coating (RC) has been introduced, and has been marketed as a restorative material in load-bearing Class I cavities (and in Class II cavities with limited size), thus serving as a possible alternative to amalgam fillings. OBJECTIVE: To discuss the outcome based on the evaluation presented in Part I of this paper, and to critically appraise the methodologies of the various studies. RESULTS: Two of the included studies were industry-funded, and status of the other clinical trials remained unclear. Quality of study reporting was considered perfectible. The use of a light-cured nanofilled resin coating material would seem advantageous, at least when regarding short- and medium term outcomes. CONCLUSION: Within the respective indications and cavity geometries, the hvGIC/RC approach would seem promising, could merge the phase-down of mercury and the objectives of minimally invasive treatment to some extent, and might be a restorative alternative for patients suffering from allergies or not willing to afford other sophisticated or expensive techniques. These recommendations are based on studies evaluating EQUIA Fil (GC), but are not transferable to clinical perspectives of the glass hybrid successor product (EQUIA Forte; GC).

Systematic review on highly viscous glass-ionomer cement/resin coating restorations (Part I): Do they merge Minamata Convention and minimum intervention dentistry?

BACKGROUND: With the Minamata Convention the use of mercury will be phased down, and this undoubtedly will have an effect on dental treatment regimens and economic resources. Composite resin restorations are considered viable alternatives to amalgam fillings; however, these will not be covered completely by health insurance systems in many countries. Recently, a high-viscosity glass-ionomer cement (hvGIC) processed with a resinous coating (RC) has been introduced, and has been marketed as a restorative material in load-bearing Class I cavities (and in Class II cavities with limited size), thus serving as a possible alternative to amalgam fillings. OBJECTIVE: To evaluate the literature on this treatment approach, and to focus particularly on the clinical performance of the hvGIC/RC combination. SEARCH STRATEGY: The Cochrane Library as well as Ebsco, Embase, PubMed, and Scopus databases were screened. Moreover, relevant abstracts published with dental meetings were reviewed. SELECTION CRITERIA: All available randomized clinical trials focusing on the hvGIC/RC approach (published either as full-texts or abstracts until June 2016) were selected. Moreover, single-group studies using hvGIC/RC were included. DATA COLLECTION AND ANALYSIS: Screening of titles and abstracts, data extraction, and quality assessments of full-texts according to Oxford scoring were performed. RESULTS: Regarding failure rates, minor differences between hvGIC/RC and GIC or composite resins as comparators could be observed in seven clinical studies. The hvGIC/RC combination showed high survival rates (with only few catastrophic failures) of up to 6 years. CONCLUSION: Class I retention rates of hvGIC/RC seem promising, but further high-quality clinical studies are clearly warranted.

Visual vs. Spectrophotometric Methods for Shade Selection.

The differences in tooth colour are important factors in the esthetic dentistry. The aim of this study was to determine the tooth colour using visual methods under natural light and "Easy Shade" device. Five hundred patients of Dental Clinic Graz Austria were selected for this study. The results of this study showed that the shade matching using "Easy Shade" device were not better than shade matching with visual methods under natural light. No difference was found between visual and digital methods in the selection of a tooth shade.