Iliac crest vertical block grafts -placing outside or inside the bone contour: A cohort study.

OBJECTIVE AND AIM: Challenging defect configurations and dimensions arise from severe, localized vertical alveolar ridge defects caused by trauma or prior surgery. This study aims to analyze three-dimensional bone gain, assess marginal bone stability in such defect configurations, and evaluate the impact of grafting outside the bone contour on the overall outcome, with a focus on iliac crest block grafts as a valid treatment option. MATERIALS AND METHODS: The prospective cohort study evaluated patients who required vertical block grafting due to localized bone defects in the maxilla or mandible and who had received iliac grafts. Three-dimensional bone gain was analyzed using cone beam computed tomography (CBCT) after 3 months of bone healing for each treated site and implant position. A comparison between bone grafts inside and outside the bone contour was conducted. Marginal bone stability was measured using intraoral radiographs during routine annual follow-up visits. RESULTS: Seventy patients with 89 treated sites were evaluated. After 3 months of graft healing, the mean vertical bone gain was 11.03 ± 3.54 mm, the mean horizontal bone gain was 7.18 ± 2.00 mm, and the mean graft length was 28.19 ± 11.01 mm. A total of 217 implants were placed in the augmented regions. On implant level, a mean vertical bone gain of 10.44 ± 3.44 mm and a mean horizontal bone gain of 6.54 ± 1.86 mm were measured. Over a 43-month observation period, mesial and distal marginal bone loss averaged 0.44 ± 0.92 mm and 0.49 ± 1.05 mm, respectively. Eight implants were diagnosed with periimplantitis, resulting in the loss of four implants, while no early implant losses were reported. CONCLUSION: Within the limitations of this study, vertical bone grafts with iliac crest block grafts were found to be a dependable treatment option for dental implant placement, and placing block grafts outside the bone contour did not lead to inferior outcomes.

Peri-implant health after microvascular head and neck reconstruction-A retrospective analysis.

INTRODUCTION: Prosthodontic rehabilitation after reconstruction with microvascular revascularized free flaps following ablative tumor surgery is challenging due to the altered anatomical and functional conditions. The aim of this retrospective study was to determine whether the type of graft and the type of peri-implant tissue have an effect on peri-implant inflammatory parameters and implant survival. MATERIALS AND METHODS: Patients who received a free flap reconstruction with subsequent implant-prosthetic rehabilitation between 2010 and 2022 were retrospectively included. The primary outcome variable was the probing depth (PPD) at a minimum of 1 year after completion of prosthetic restoration. Predictive variables were type of free flap, emergence profile, and history of radiation. RESULTS: Seventy-one patients after free flap reconstruction were included in the analysis. At a minimum of 24 months after implant insertion the primary outcome, PPD showed no clinically relevant differences between the types of free flaps used. The emergence profile through a skin island resulted in an increase in BOP compared to native mucosa in the descriptive analysis (p-value > .05). The analysis showed a 5-year implant survival of 96.2% (95% CI: 0.929-0.996) in cases without irradiation and 87.6% (95% CI: 0.810-0.948) with irradiation of the region evaluated (p-value .034). CONCLUSION: Flap and associated soft tissue type had no significant effect on 5-year implant survival or peri-implant inflammatory parameters. However, the large heterogeneity of the patient population indicates that further prolonged studies are required for a more differentiated assessment of the long-term success.

Full block or split block?-Comparison of two different autogenous block grafting techniques for alveolar ridge reconstruction.

OBJECTIVE: To evaluate radiographic bone gain after alveolar ridge augmentation with two different designs of autogenous block graft harvested from the mandible. MATERIALS AND METHODS: Alveolar ridge defects were evaluated by preoperative cone beam computed tomography (CBCT) and grafted in a staged approach using intraoral block grafts. The ridge augmentation was either performed using the full-block technique (group 1) or the split-block technique (cortical plate with autogenous bone chips) (group 2). After 4 months of bone healing, a further CBCT scan was performed before implant placement. Horizontal and vertical bone gain were measured. RESULTS: In this retrospective study, 91 patients were grafted with block grafts (36 patients with full-block grafts; 55 patients with split-block grafts) resulting in 171 block grafts in total. The mean horizontal bone gain was 3.37 ± 0.71 mm in group 1 and 5.79 ± 2.20 mm in group 2. A linear mixed-effect model also showed a statistically significant group difference (p < 0.001, estimate: 3.455, 95% CI: [2.082-4.829]). The mean vertical bone gain was 2.85 ± 0.73 mm in group 1 and 7.60 ± 1.87 mm in group 2. A linear mixed-effect model also showed a statistically significant group difference (p: 0.029, estimate: 3.126, 95% CI: [0.718-5.557]). Mean marginal bone level was 0.33 ± 0.37 mm (group 1) and 0.17 ± 0.29 mm (group 2). CONCLUSION: The split-block technique resulted in a greater bone gain than the full-block technique. This effect was observed in both the vertical and the horizontal dimensions.