The assessment of the effect of the size of lateral-antrostomy in graftless balloon elevation of the maxillary sinus membrane with simultaneous implant placement (a randomized controlled clinical trial).

BACKGROUND: The overlying maxillary sinus frequently restrains the height of the posterior maxillary bones. PURPOSE: Evaluating the effect of downsizing the antrostomy side-window on the stability of the installed implants and vertical bone gain, after employing a graftless antral membrane balloon elevation (AMBE). MATERIALS AND METHODS: The study is a randomized controlled clinical trial conducted on 20 patients with 30 deficient maxillary alveolar ridges underwent graftless (AMBE) after being allocated into a (5 mm) entry antrostomy group (the test group) and a (10 mm) entry antrostomy group (the control group) implementing a radiographic linear bone height and implant stability quotations (ISQ) comparison among both groups immediately after the placement of 38 Implants and 6 months after. RESULTS: Radiographic bone gain of the test group (5.55 ± 0.93 mm) was significantly higher than the control group (2.86 ± 0.60 mm) (p <0.001). There was no significant difference in primary stability between the test (65 ± 5.32) and control groups (62.67 ± 4.46) (p = 0.202); while the test group (73.43 ± 4.39) showed significantly higher secondary stability than the control group (64.83 ± 6.05) (p <0.001). ISQ values recorded at 6 months were significantly higher than those recorded at insertion in the test group (p <0.001), while they were insignificant in the control group (p = 0.148). CONCLUSION: Undersizing the antrostomy window deemed beneficial concerning the vertical bone gain and the simultaneously placed root form dental implants' secondary stability.

Computer-guided calvarial mono-cortical bone blocks harvest: A novel approach for three-dimensional alveolar reconstruction of atrophic maxilla.

BACKGROUND: Calvarial bone grafts have been one of the grafting options that provides predictable results for three-dimensional reconstruction of severely atrophied ridges owing to their low resorption and rapid revascularization, thus providing adequate volume for implant insertion. The aim of this study was to introduce a computer-guided technique for calvarial graft harvest to minimize the complications known with grafting from this donor site. MATERIALS AND METHODS: Eight patients, suffering from severely atrophied, completely edentulous maxillary ridges, with an age range (21-30 years) were operated on (six males and two females). A custom-made guide for each patient based on preoperative computed tomography (CT) was fabricated for harvesting the outer table cortical bone blocks from the parietal bone, then particulate bone was collected with an auto-chip maker. Bilateral sinus lifting was indicated in all cases. The bone blocks were fixed intraorally and the bone particulates filled the gaps and the volume created by sinus lifting, then the whole complex was covered with collagen membranes fixed with titanium tacks. Immediate and 6 months CT were requested for evaluation of the guide accuracy and the graft integration, respectively. RESULTS: In all cases, the guide was found to accurately fit into its preplanned position and to correctly locate the anticipated harvest site with the needed dimensions of the bone blocks. No intraoperative complications were encountered such as breakage through the inner table or cerebrospinal fluid leakage. Postoperatively, all the cases showed uneventual healing except one case that had an anterior dehiscence. CONCLUSION: The computer-guided calvarial bone blocks harvest from the parietal bone is safe and predictable technique for three-dimensional reconstruction of severely atrophic edentulous maxilla.