Colour stability and surface properties of high-translucency restorative materials for digital dentistry after simulated oral rinsing.

High-translucency restorative materials are commonly used in the restoration of anterior teeth where aesthetics is a critical factor. In this in vitro study, the impact of mouthwash on the colour stability and surface characteristics of high-translucency computer-aided design and computer-aided manufacturing (CAD-CAM) dental restorative materials was evaluated. Two-hundred specimens were fabricated from five high-translucency CAD-CAM materials: a resin nano ceramic; a polymer-infiltrated ceramic network; a feldspathic ceramic; a lithium disilicate glass ceramic; and high-translucency zirconia. Each group of ceramic specimens was then divided into four subgroups: conventional mouthwash (LISTERINE); whitening mouthwash (LISTERINE Healthy White); chlorhexidine gluconate; and distilled water. Oral rinsing was simulated at 100 rpm for 180 h, representing 15 yr of clinical simulation. The specimens were then evaluated for colour, translucency, gloss, roughness, and surface morphology. Two-way ANOVA and linear mixed models were used for intergroup comparisons (α = 0.05). The polymer-infiltrated ceramic network and feldspathic ceramic became brighter, more opaque, less glossy, and rougher after rinsing with the whitening mouthwash. The long-term use of specific mouthwashes can cause deterioration of the optical and surface properties of high-translucency CAD-CAM dental restorations.

Leukocyte- and platelet-rich fibrin is an effective membrane for lateral ridge augmentation: An in vivo study using a canine model with surgically created defects.

BACKGROUND: Leukocyte- and platelet-rich fibrin (L-PRF) has been suggested to enhance bone healing and the effects of L-PRF need to be evaluated in lateral residual alveolar bone augmentation. This in vivo study aimed to analyze the effects of L-PRF as a membrane on bone regeneration in lateral residual alveolar augmentation. METHODS: Eight mongrel dogs were used; the mandibular premolars were extracted and then three lateral ridge defects were surgically created on each side of the arch. After 4 weeks, guided bone ridge augmentation was performed in each defect with the following treatment groups: N+D (nonresorbable membrane with deproteinized bovine bone mineral [DBBM]), N+B (nonresorbable membrane with ß-tricalcium phosphate [ß-TCP]), R+D (resorbable membrane with DBBM), R+B (resorbable membrane with ß-TCP), and P+D (L-PRF with DBBM), and P+B (L-PRF and ß-TCP). Following 4 weeks of bone healing, the new bone amount for each group was measured by light microscopy (primary outcome) and microcomputed tomography (micro-CT) (secondary outcome). The mean values were compared at the 0.05 significance level. RESULTS: The P+D group showed the most newly formed bone in histology and in micro-CT analyses. L-PRF was more effective in bone regeneration when compared to nonresorbable and resorbable barrier membranes. Additionally, this study indicated DBBM was the more favorable osseous graft material for bone regeneration than ß-TCP when barrier membranes are used. CONCLUSION: From the results of this in vivo study using surgically created defects, L-PRF plays an effective role as a barrier membrane for lateral ridge augmentation. L-PRF may be an excellent barrier membrane in place of other nonresorbable and resorbable membranes.