Quantitative Measurements of the Depth of Enamel Demineralization before and after Bleach: An In Vitro Study

Objective. This study is aimed at determining two main points. First, if the Canary System™ (CS), initially used to assess caries, can measure a decalcification depth of bleached enamel quantitatively, and second, whether or not whitening has a harmful effect on enamel. This device can be considered a useful tool in the clinical assessment of the progression of demineralization after bleaching. Materials and Methods. This study collected sixty human premolars that are in a good state recently extracted for orthodontic reason. To properly disinfect and preserve the premolars, they were stored in a saline solution and later in distilled water for a period of two weeks to allow the premolars to rehydrate. Later, 24 hours before the experiment, the premolars were introduced into a solution of artificial saliva to acquire back their minerals. The mineral content of the teeth was measured by the Canary System™ before bleaching. The teeth were bleached with 30% hydrogen peroxide (fläsh HP 30%), 30 min per week and for 3 consecutive weeks to simulate the conditions of strong bleaching in the clinic. The extent of demineralized enamel was measured by the Canary System™ at three points on the enamel surface of each tooth. The data were averaged for each application of the bleaching product. The demineralization extent of the teeth was measured by the Canary System™ before and after bleaching. The significance level was set at 0.05, and SPSS version 26 was used. The data were analyzed by using Wilcoxon’s and Student’s tests. Results. Mineral loss occurred after the first bleaching session; the Canary System™ detected a decalcification in the first bleaching session ( μm) compared to the other sessions (), while no significant change was detected between the second and the third sessions (). Conclusion. Based on the findings of the present study, under in vitro conditions, it was possible to measure the demineralization extent of bleached enamel with the Canary System™

In vitro evaluation of the color stability and surface roughness of a new composite flow

The aim of this study was to evaluate the color stability and the surface roughness of a bulk-fill composite flow (SDR® Plus) by comparison to an ORMOCER-based composite (Ceram.x® Universal SphereTEC?) in order to confirm the validity of using SDR® Plus

Ceramic veneers: a case report

Contemporary dentistry’s main aim is to re-establish a patient’s esthetic appearance. In order to achieve this goal, minimal invasive techniques are required such as bleaching, direct composites and indirect ceramic veneer restorations, instead of ceramic crowns. Many problems in the esthetic zone may be resolved with bleaching techniques but the need for an alternative for crowns- when bleaching is impossible to achieve or gives insufficient results- led to the advent of laminate veneers.These techniques may be processed in two different ways: direct or indirect. Direct laminate veneers are prepared in the dental clinic by applying layers of composite material directly to the prepared tooth surface. Indirect laminate veneers may be produced from ceramic materials, in the dental laboratory.In this case report, ceramic veneers were used for a patient with esthetic problems related to cervical abrasion and discolorations on her upper canines and premolars. The preparation and cementation are described step-by-step and the technique discussed.As a conclusion, ceramic veneer restorations may be a treatment option for patients with esthetic problems similar to the one reported in this case

Evaluation of dental parameters perception by Lebanese prosthodontists, orthodontists and aesthetic doctors

The aim of this study was to compare the effect of varying smile parameters with respect to three indices between Lebanese dentists (prosthodontists and orthodontists) and medical doctors. 245 participants were divided into 3 groups. A photograph of the smile that conforms to a woman’s aesthetic standards has been digitally altered to provide a reference image. Next, images where modified then evaluated. The collected data was analyzed. Dental professionals critically judged dental aesthetics by focusing on the gingivo-dental characteristics that make the smile less pleasant. Dental professionals detected minimal dental discrepancies in a smile, unlike doctors who assessed the smile in relation to the entire face since their judgment is global. Lebanese doctors have a different perception of oral aesthetics from Lebanese prosthodontists and orthodontists

A Two-Year Comparative Evaluation of Clinical Performance of a Nanohybrid Composite Resin to a Flowable Composite Resin

Objective: This prospective in vivo study aimed to compare the clinical behavior of a flowable composite resin (Genial Universal Flo, GC) and a nanohybrid universal composite resin (Tetric Evo Ceram, Ivoclar Vivadent) used in Class I and II direct esthetic restorations in posterior teeth. Methods: A total of 108 Class I and II direct restorations were performed in patients aged between 20 and 60 years. The originality of this study lies in the fact that both materials were placed in pairs, in the same clinical environment (i.e., the same patient and the same type of tooth). The evaluations were performed now of restoration and after 2-weeks, 6-, 12-, and 24-months intervals using clinical examination, clinical photographs, and radiological examination, according to modified USPHS criteria. Statistical analysis was performed using the Fisher exact test and chi-square analysis. Results: At baseline, the universal composite resin showed better esthetic properties such as surface luster, surface staining marginal staining. Both materials regressed significantly over time with no significant difference between groups. Conclusions: Both flowable and nanohybrid composite resins exhibit acceptable clinical performance. The present 24 months of evaluation of different composites showed that the G-ænial Universal Flo could be an effective esthetic material for posterior restoration. No significant difference between both materials over time concerning surface luster, surface staining, and marginal staining