Clinical Outcomes and Gingival Blood Flowmetry of Two Types of Subepithelial Connective Tissue Graft for Root Coverage in Multiple Gingival Recessions: A Preliminary Study.

This randomized split-mouth preliminary clinical trial aimed to evaluate periodontal parameters and gingival blood flowmetry, comparing sites that received subepithelial connective tissue graft from the palate after deepithelialization (DE) or obtained with parallel incision (PI). Periodontal parameters were evaluated at baseline and 6 months postoperative. Gingival blood flows were analyzed by laser Doppler flowmetry (LDF) at baseline and 2, 7, and 14 days postoperative. Statistical and LDF analyses were performed with R version 3.5.1 and MATLAB software, and clinical parameters through ANOVA and Wilcoxon signed-rank tests. LDF showed superior decrease in power spectral density (PSD) for DE after 2 days. After 7 days, PSD returned to initial values only for PI, and DE had not returned to the initial values by day 14. Despite major initial revascularization challenges for DE sites, both grafts promoted satisfactory root coverage in the treatment of multiple gingival recessions.

Bone demineralization improves onlay graft consolidation: A histological study in rat calvaria.

BACKGROUND: Previous data suggest that bone demineralization may promote bone graft consolidation as well as proliferation and differentiation of pre-osteoblasts, but the biological mechanisms involved in this process need to be clarified. This study investigated the effects of bone demineralization with citric acid (CA) and tetracycline (TCN) on the repair of onlay bone grafts. METHODS: Onlay bone grafts were performed on the calvaria of 126 Wistar rats. The contacting surfaces between bone graft and receptor bone bed were demineralized for 15, 30, and 60 seconds with TCN (50 mg/mL), or 10% CA, (pH 1), constituting the following test groups (n = 18): TCN15, TCN30, TCN60, CA15, CA30, and CA60. Control grafts (C) were performed without demineralization (n = 18). After 7, 30, and 60 days, biopsies were obtained for quantitative and qualitative histological analysis (a = 6). RESULTS: Demineralization accelerated the bone repair early from 7 days of healing. Higher percentage area of newly formed bone was observed in CA15 and TCN60 groups when compared to C in all evaluation periods (P = 0.02). At 30 days, C specimens had lower percentage of consolidated surfaces than TCN60, TCN30 and CA15 (P = 0.0015). At 60 days, CA15, CA60, and TCN60 presented bone surfaces almost completely filled by newly formed bone, against about 75% in C specimens (P = 0.0015). CONCLUSIONS: Both CA and TCN were effective in accelerating osteogenesis at the interface between bone grafts and receptor bone beds, especially when applied for 15 seconds and 60 seconds, respectively.

Bone Graft and Substitutes Associated with Titanium Dome for Vertical Bone Formation in Osseointegrated Implants: Histomorphometric Analysis in Dogs.

PURPOSE: This animal study investigated vertical bone formation (VBF) around implants and used histomorphometric analysis to compare different bone-filling materials associated with a massive titanium dome as a tissue barrier. MATERIALS AND METHODS: Seven dogs were submitted to surgical procedures with extraoral access to the lower edge of the mandible, and four implants were semi-inserted in each animal. Each implant received one treatment: autogenous bone with clot (AB), control clot (C), synthetic graft (Biogran [BG]), or xenograft (Bio-Oss [BO]). Massive titanium domes were stabilized over the implants. Histologic analysis was performed after 3 months, and quantitative aspects were evaluated in extraosseous and intraosseous threads on Image Pro-Plus software. RESULTS: VBF around implants exhibited significant values in AB compared with other groups. BG and BO presented statistical equivalency to AB and C in the apposition and filling of extraosseous threads. There was no difference between groups for parameters evaluated in intraosseous threads. CONCLUSION: The experimental model was valid for evaluation of VBF around implants placed in atrophic mandibles. Considering the limitations of this study, histomorphometric analysis evidenced better outcomes for group AB. Even though groups BG and BO presented worse outcomes than AB, they were slightly better compared with the control group.