based on the book chapter by Gustavo Avila-Ortiz andPablo Galindo-Moreno Summary This technique is used to gain bone height in posterior atrophic maxillary segments before implant placement. It is increasingly used in patients with maxillary sinuses that are too close to the upper jaw or excessive bone reabsorption from gum disease. Endpoints relate to the amount of new bone formation after grafting and survival of implants and implant-supported prostheses. and long-term success rates are high. It is also excellent for studying healing following grafting with different materials and regenerative strategies in large craniofacial defects. The protocol described here is based on a hypothetical study, and covers patient screening, selection, enrolment and randomization, including a sample size calculation (which is omitted in most published studies). There are multiple phases for planning and executing the sinus elevation, followed by post-operative evaluation, and further planning and placement of implants. Detail is given on the length and form of patient visits for evaluations using cone-beam CT, impressions, photos, clinical measures, bone biopsies and adverse events recording. The discussion is supplemented by images of bone core histology and diagrams of the paranasal sinuses, and the authors point out the difference between crestal and lateral approaches. The lateral approach is illustrated throughout, including follow-up at 24 weeks and implant placement. The authors also address the problems of membrane perforation and nasal meatus occlusion. Open full-text PDF (1.9 MB)

Objectives: The study aimed to evaluate soft and hard tissue alterations following flapless immediate implant placement and provisionalisation in sockets with a facial bone dehiscence that were reconstructed and received different soft tissue grafts in a proof-of-principle, randomised clinical trial of 1-year duration. The hypothesis was that the use of a soft tissue graft would reduce gingival margin apical migration at the facial aspect. Methods: Twenty-four patients with a single failing maxillary incisor presenting with a facial bone dehiscence were selected. After tooth extraction and narrow implant installation with a torque in excess of 32 N/cm, patients were randomised into three groups (n = 8): a control group (CTL) with no soft tissue graft; a collagen matrix (CM) group using Mucograft[tm]; and a connective tissue graft group (CTG) using subepithelial connective tissue from the palate. Sockets were reconstructed with inorganic bovine bone mineral containing 10% of porcine collagen (Bio-Oss Collagen[tm]) and a non-cross-linked collagen membrane (Bio-Gide[tm]). Additionally, a provisional with a concave subgingival contour an no occlusal contacts was installed in the implants. Clinical, photographic, aesthetic and tomographic analyses were performed by a blinded examiner at baseline, 6 months and 12 months to evaluate tissue alterations. Results: All implants were successfully osseointegrated and a few minor complications occurred. Gingival margin apical migrations of 0.72 ± 0.57mm, 0.42 ± 0.60mm and –0.04 ± 0.3mm occurred respectively in groups CTL, CM and CTG; this was significantly lower in the CTG group than the CTL group. Soft tissue thickness was significantly increased at 12 months for CTL (2.11 ± 0.60mm), CM (2.1 ± 0.54mm) and CTG (3.04 ± 0.61mm. The CTG group demonstrated significantly greater thickness and alveolar ridge contour in comparison to CTL and CM. No significant differences were observed between groups in terms of aesthetic evaluation, papilla apical migration, and height and thickness of the bone in contact with the facial aspect of the implant. In five patients, it was not possible to completely reconstruct the facial bone wall; this was related to the transverse format of the ridge defect, influencing both facial bone height and thickness. Conclusion: Minimal soft tissue alterations occur after immediate implant and provisional placement in sockets with buccal bone dehiscences 1 year after the surgical procedure. The use of connective tissue grafts avoids gingival margin apical migration, and provides better contour of the alveolar ridge and greater thickness of the soft tissue at the buccal aspect of the implant.