Vertical bone regeneration with deproteinised bovine bone mineral or biphasic calcium phosphate in the rabbit calvarium: effect of autologous platelet lysate.

Although bone substitutes associated with platelet concentrates are widely used to vertically reconstruct alveolar ridges, their respective and specific contribution remain controversial. The aim of this study was to evaluate the benefit of using either biphasic calcium phosphate (BCP) or demineralised bovine bone mineral (DBBM) alone or with autologous platelet lysate (APL) in vertical bone regeneration. The study involved fourteen New Zealand rabbits. Autologous APL was prepared by freeze-thawing from a platelet suspension (10(9) platelets/ml). Four CP titanium (cpTi) cylinders were fixed to each calvarium; one cylinder was empty, one was filled with APL alone and the others were filled either with BCP or BCP + APL or DBBM or DBBM + APL. New bone formation and biomaterial resorption were evaluated using non-demineralised histology and histomorphometry. After 6 weeks, new bone formation was observed in all cylinders. The newly formed bone in the cylinders filled with APL alone, DBBM and BCP was significantly increased by (0.6-, 2.5- and 3.3-fold, respectively) (P < 0.0001) compared to results obtained with the empty cylinders. Vertical bone height in the cylinders filled with BCP was greater to that observed with DBBM. The residual material in the cylinders filled with BCP was significantly (P < 0.0001) lower (0.35-fold) than that with DBBM. Both newly formed bone and residual material in the cylinders filled with BCP + APL or DBBM + APL were similar to those filled with either BCP or DBBM, respectively. This study provided evidence that APL alone, as well as DBBM and BCP, have a beneficial effect on vertical bone formation and remodelling. APL associated with either DBBM or BCP did not provide additional benefits.

Assessment of the association between the Implant Disease Risk Assessment (IDRA) tool and peri-implantitis: a retrospective cohort study with up to 8 years of follow-up.

The aim of this study was to evaluate the accuracy of the Implant Disease Risk Assessment (IDRA) tool in predicting the occurrence of peri-implantitis in patients who have received at least one implant, with a follow-up of up to 8 years. The records of patients who received one or more implants in the periodontology or oral surgery department of Saint Joseph University of Beirut between 2014 and 2018 were collected. Parameters related to the IDRA tool were obtained and the risk level calculated. Patients were recalled to assess their peri-implant status. The association between the IDRA risk level and the incidence of peri-implantitis was estimated. Overall, 145 patients were included in the study. A statistically significant association was found between the IDRA risk levels and the incidence of peri-implantitis (P = 0.003). High risk patients had 5.2 times higher odds of developing peri-implantitis than low-to-moderate risk patients (P < 0.001). Receiver operating characteristic curve analysis demonstrated a 69% probability that IDRA can identify patients at risk of developing peri-implantitis (P = 0.003). Further analysis found the percentage bleeding on probing to be the only significant IDRA vector. Within the limitations of this study, the IDRA tool is considered potentially useful for identifying patients at risk of developing peri-implantitis. It may serve as one component of a comprehensive peri-implant assessment, pending further enhancement of its predictive precision. Moreover, this tool can be considered before implant placement and during the periodontal maintenance phase. TRIAL REGISTRATION: ClinicalTrials.gov: NCT04888572.

Biotribocorrosion (tribo-electrochemical) characterization of anodized titanium biomaterial containing calcium and phosphorus before and after osteoblastic cell culture.

The purpose of this study was to investigate the relationship between the osteoblastic cells behavior and biotribocorrosion phenomena on bioactive titanium (Ti). Ti substrates submitted to bioactive anodic oxidation and etching treatments were cultured up to 28 days with MG63 osteoblast-like cells. Important parameters of in vitro bone-like tissue formation were assessed. Although no major differences were observed between the surfaces topography (both rough) and wettability (both hydrophobic), a significant increase in cell attachment and differentiation was detected on the anodized substrates as product of favorable surface morphology and chemical composition. Alkaline phosphatase production has increased (≈20 nmol/min/mg of protein) on the anodized materials, while phosphate concentration has reached the double of the etched material and calcium production increased (over 20 µg/mL). The mechanical and biological stability of the anodic surfaces were also put to test through biotribocorrosion sliding solicitations, putting in evidence the resistance of the anodic layer and the cells capacity of regeneration after implant degradation. The Ti osteointegration abilities were also confirmed by the development of strong cell-biomaterial bonds at the interface, on both substrates. By combining the biological and mechanical results, the anodized Ti can be considered a viable option for dentistry.