Comparative analysis of lateral maxillary sinus augmentation with a xenogeneic bone substitute material in combination with piezosurgical preparation and bony wall repositioning or rotary instrumentation and membrane coverage: a prospective randomized clinical and histological study.

OBJECTIVES: The present randomized controlled clinical study aimed to investigate if, in lateral maxillary sinus augmentation, the repositioned bony wall or the application of a collagen membrane results in more preferable new hard tissue formation. MATERIALS AND METHODS: Forty patients were divided into two study groups. Both groups received a xenogeneic bone substitute material (BSM) during lateral sinus augmentation. In the bony wall group (BW), following piezosurgery, the retrieved bony wall was repositioned. In the collagen membrane group (CM), following rotary instrument preparation, collagen membrane coverage was applied. After 6 months, biopsies were taken to histologically analyze the percentage of BSM, connective tissue (CT), and newly formed bone (NFB) following both approaches. RESULTS: Forty implants were placed and 29 harvested biopsies could be evaluated. Duration of surgery, membrane perforations, and VAS were detected. Histomorphometrical analysis revealed comparable amounts of all analyzed parameters in both groups in descending order: CT (BW: 39.2 ± 9%, CM: 37,9 ± 8.5%) > BSM (BW: 32.9 ± 6.3%, CM: 31.8 ± 8.8%) > NB (BW: 27.8 ± 11.2%, CM: 30.3 ± 4.5%). CONCLUSIONS: The results of the present study show that the closure of the access window by means of the retrieved bony wall or a native collagen membrane led to comparable bone augmentation results. CLINICAL TRIAL: clinicaltrials.gov NCT04811768. CLINICAL RELEVANCE: Lateral maxillary sinus augmentation with the application of a xenogeneic BSM in combination with a native collagen membrane for bony window coverage represents a reliable method for surgical reconstruction of the posterior maxilla. Piezosurgery with bony window repositioning delivers comparable outcomes without membrane coverage.

Accuracy of half-guided implant placement with machine-driven or manual insertion: a prospective, randomized clinical study.

OBJECTIVES: To compare the accuracy of implant placement performed with either a surgical motor or a torque wrench as part of a half-guided surgical protocol. MATERIALS AND METHODS: Implant insertion with half-guided surgical protocol was utilized by surgical motor (machine-driven group) or torque wrench (manual group) in the posterior maxilla. After the healing period, accuracy comparison between planned and actual implant positions was performed based on preoperative cone beam computed tomography and postoperative digital intraoral scans. Coronal, apical, and angular deviations, insertion time, and insertion torque were evaluated. RESULTS: Forty patients were treated with 1 implant each; 20 implants were inserted with a surgical motor and 20 implants with a torque wrench. Global coronal and apical deviations were 1.20 ± 0.46 mm and 1.45 ± 0.79 mm in the machine-driven group, and 1.13 ± 0.38 mm and 1.18 ± 0.28 mm in the manual group (respectively). The mean angular deviation was 4.82 ± 2.07° in the machine-driven group and 4.11 ± 1.63° in the manual group. Mean insertion torque was 21.75 ± 9.75 Ncm in the machine-driven group, compared to 18.75 ± 7.05 Ncm in the manual group. Implant placement duration was 9.25 ± 1.86 s in the machine-driven group at a speed of 50 rpm, and 36.40 ± 8.15 s in the manual group. CONCLUSION: No significant difference was found between the two groups in terms of accuracy and mean insertion torque, while machine-driven implant placement was significantly less time-consuming. CLINICAL RELEVANCE: Optimal implant placement accuracy utilized by half-guided surgical protocol can be achieved with both machine-driven and torque wrench insertion. TRIAL REGISTRATION: ID: NCT04854239.

Vertical-guided bone regeneration with a titanium-reinforced d-PTFE membrane utilizing a novel split-thickness flap design: a prospective case series.

OBJECTIVES: To evaluate the feasibility of a newly proposed minimally invasive split-thickness flap design without vertical-releasing incisions for vertical bone regeneration performed in either a simultaneous or staged approach and to analyze the prevalence of adverse events during postoperative healing. MATERIALS AND METHODS: Following preparation of a split-thickness flap and bilaminar elevation of the mucosa and underlying periosteum, the alveolar bone was exposed over the defects, vertical GBR was performed by means of a titanium-reinforced high-density polytetrafluoroethylene membrane combined with particulated autogenous bone (AP) and bovine-derived xenograft (BDX) in 1:1 ratio. At 9 months after reconstructive surgery, vertical and horizontal hard tissue gain was evaluated based on clinical and radiographic examination. RESULTS: Twenty-four vertical alveolar ridge defects in 19 patients were treated with vertical GBR. In case of 6 surgical sites, implant placement was performed at the time of the GBR (simultaneous group); in the remaining 18 surgical, sites implant placement was performed 9 months after the ridge augmentation (staged group). After uneventful healing in 23 cases, hard tissue fill was detected in each site. Direct clinical measurements confirmed vertical and horizontal hard tissue gain averaging 3.2 ± 1.9 mm and 6.5 ± 0.5 mm respectively, in the simultaneous group and 4.5 ± 2.2 mm and 8.7 ± 2.3 mm respectively, in the staged group. Additional radiographic evaluation based on CBCT data sets in the staged group revealed mean vertical and horizontal hard tissue fill of 4.2 ± 2.0 mm and 8.5 ± 2.4 mm. Radiographic volume gain was 1.1 ± 0.4 cm3. CONCLUSION: Vertical GBR consisting of a split-thickness flap and using titanium-reinforced non-resorbable membrane in conjunction with a 1:1 mixture of AP+BDX may lead to a predictable vertical and horizontal hard tissue reconstruction. CLINICAL RELEVANCE: The used split-thickness flap design may represent a valuable approach to increase the success rate of vertical GBR, resulting in predicable hard tissue regeneration, and favorable wound healing with low rate of membrane exposure.

Demonstration of Radiographic Bone Fill in Postextraction Sockets Using a Novel Implant-Site Development Technique: A Retrospective Comparative Case Series.

The objective of this study was to compare the novel extraction-site development (XSD) technique with spontaneous healing. Advanced alveolar defects (extraction defect sounding, classes 3 and 4) at 33 single-rooted teeth were treated by XSD (test), and 21 extraction sites of single-rooted teeth were left for spontaneous healing (control). In pre- and postoperative cone beam computed tomography (CBCT) data sets, orovestibular and vertical socket dimensions were assessed, as were socket areas. XSD resulted in complication-free healing with significantly higher radiographic bone fill compared to spontaneous healing. Application of the XSD approach may reduce the need for augmentative procedures during implant placement.