Long-term survival of Astra Tech vs Straumann dental implants and restorations.

DESIGN: This randomized controlled trial (RCT) compared the survival and complications rates between two well-established implant systems, namely AST (OsseoSpeed TX 3.0-5.0 S, TX 4.5; Astra Tech Implant System, Dentsply Sirona) and STM (Straumann Bone Level Implants 3.3, 4.1, 4.8 mm, SLA active; Straumann AG), supporting fixed restorations, over a 10-year follow-up period. CASE SELECTION: Sixty-four healthy patients with good oral hygiene participated in this study at the Clinic of Reconstructive Dentistry, University of Zurich, Switzerland. A total of 98 implants were placed in these patients, who were randomly assigned to either the AST or the STM groups. Subsequently, patients received implant-supported fixed restorations and were followed up for 10 years. The assessments were performed at the implant insertion stage after the final implant restoration was fitted (baseline), and then at 1, 3, 5, 8, and 10 years post-baseline assessment. The outcome measures included implant survival, marginal bone level changes, prosthesis (supra-structure) complications, and clinical periodontal measures. DATA ANALYSIS: Data analysis was performed with SAS 9.4 software. Data were recorded at both the patient and implant levels. A range of statistical tests such as Wilcoxon-signed-rank, Wilcoxon-Mann-Whitney, F-tests, and Chi-squares were used. Linear models and linear mixed models were applied at the patient and implant levels, respectively. RESULTS: The study reported survival rates of 89.7% for AST and 96.8% for STM, after 10 years. The AST implants showed a higher incidence of prosthesis complications, such as chipping, screw loosening and fracture, abutment fracture, and implant crown loss. Biological complications, including peri-implant mucositis and peri-implantitis, were more prevalent in the STM group. CONCLUSIONS: Overall, the study suggests that both implant systems have equally high survival rates and stable marginal bone levels. Therefore, both systems are considered viable options for supporting fixed restorations at restoring missing teeth in the maxilla and mandible.

The homeostasis and therapeutic applications of innate and adaptive immune cells in periodontitis.

OBJECTIVES: Periodontitis (PD) is one of the most common dental disorders. This chronic oral inflammation is caused by complicated interrelations between bacterial infections, dysregulated immune reactions, and environmental risk factors. A dysregulated immune response can lead to inflammatory bone resorption by allowing the recruitment of pro-inflammatory immune cells to the periodontal tissues. SUBJECTS: The recruitment of innate and adaptive immune cells in PD initiates the acute and following chronic inflammatory processes. The inflamed tissues, on the other hand, can be restored if the anti-inflammatory lineages are predominantly established in the periodontal tissues. Therefore, we aimed to review the published literature to provide an overview of the existing knowledge about the role of immune cells in PD, as well as their possible therapeutic applications. RESULTS: Experimental studies showed that drugs/systems that negatively regulate inflammatory cells in the body, as well as interventions aimed at increasing the number of anti-inflammatory cells such as Tregs and Bregs, can both help in the healing process of PD. CONCLUSION: Targeting immune cells or their positive/negative manipulations has been demonstrated to be an effective therapeutic method. However, to use this sort of immunotherapy in humans, further pre-clinical investigations, as well as randomized clinical trials, are required.