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Thirty-eight patients (aged 25 to 74) requesting extraction-socket and sinus augmentation procedures (27 and 11 patients, respectively) prior to implant placement volunteered to participate in this case series protocol. Surgical sites were grafted with either biphasic calcium phosphate (BCP) + collagen (for extraction-socket augmentation) or BCP with a collagen barrier membrane (for maxillary sinus augmentation). All patients completed the 1-year postloading follow-up, which consisted of clinical and radiographic evaluations. No implants were lost, and both healthy soft tissue support and good radiographic evidence of supporting bone were found around implants. The result of this short-term evaluation of implants placed in areas grafted with alloplasts seemed to be favorable and promising.

Objective: The effect on the marginal peri-implant tissues following repeated platform switching abutment removal and subsequent reconnection was studied., Material and Methods: Six adult female Beagle dogs were selected, and Pm3 and Pm4 teeth, both left and right sides, were extracted and the sites healed for 3 months. At this time, 24 bone level (BL) (Straumann, Basel, Switzerland) Ø 3.3/8 mm implants were placed, 2 in each side on Pm3 and Pm4 regions. In one side (control group), 12 bone level conical Ø 3.6 mm healing abutments and, on the other side (test group), 12 Narrow CrossFit (NC) multibase abutments (Straumann) , Basel, Switzerland) were connected at time of implant surgery. On test group, all prosthetic procedures were carried out direct to multibase abutment without disconnecting it, where in the control group, the multibase abutment was connected/disconnected five times (at 6/8/10/12/14 weeks) during prosthetic procedures. Twelve fixed metal bridges were delivered 14 weeks after implant placement. A cleaning/control appointment was scheduled 6 months after implant placement. The animals were sacrificed at 9 months of the study. Clinical parameters and peri-apical x-rays were registered in every visit. Histomorphometric analysis was carried out for the 24 implants. The distance from multibase abutment shoulder to the first bone implant contact (S-BIC) was defined as the primary histomorphometric parameter., Results: Wilcoxon comparison paired test (n = 6) found no statistically significant differences (buccal P = 0.917; Lingual P = 0.463) between test and control groups both lingually and buccally for S-BIC distance. Only Pm3 buccal aBE-BC (distance from the apical end of the barrier epithelium to the first bone implant contact) (P = 0.046) parameter presented statistically significant differences between test and control groups. Control group presented 0.57 mm more recession than test group, being this difference statistically significant between the two groups (P < 0.001)., Conclusion: It can be conclude, within the limits of this animal study, that the connection/disconnection of platform switching abutments during prosthetic phase of implant treatment does not induce bone marginal absorption. Furthermore, it may present a negative influence in the buccal connective tissue attachment that becomes shorter anyway preventing marginal hard tissue resorption, especially in thin biotypes., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To assess the marginal soft tissue healing process after flap or flapless surgery in immediate implant placement in a dog model., Material and Methods: This study was carried out on five Beagle dogs. Four implants were placed in the lower jaw in each dog immediately after tooth extraction. Flap surgery was performed before the extraction on one side (control) and flapless on the other (test). After 3 months of healing, the dogs were sacrificed and prepared for histological analysis., Results: Ten implants were placed in each group. Two failed (one of each group). The length of the junctional epithelium in the flapless group was 2.54 mm (buccal) and 2.11 mm (lingual). In the flap group, the results were very similar: 2.59 mm (buccal) and 2.07 mm (lingual), with no significant differences observed between the groups. The length of the connective tissue in the flapless group was 0.68 mm (buccal) and 0.54 mm (lingual), and 1.09 mm at the buccal and 0.91 mm at the lingual aspect in the flap group, with no significant differences between groups. The difference between the mean distance from the peri-implant mucosa margin to the first bone-implant contact at the buccal aspect was significant between both groups (3.02 mm-flapless and 3.69 mm flap group). However, this difference was mostly due to the Pm3 group (flapless: 2.95/flap: 3.76) because no difference could be detected in the Pm4 group. Both groups showed minimal recession, with no significant differences between groups (flapless group - 0.6 mm buccal and 0.42 mm lingual; flap group - 0.67 and 0.13 mm)., Conclusion: The clinical evaluation of immediate implant placement after 3 months of healing indicated that buccal soft tissue retraction was lower in the flapless group than in the flap group, without significant differences. The mean values of the biological width longitudinal dimension at the buccal aspect were higher in the flap group than in the flapless group, this difference being mostly due to the Pm3, probably because of a thinner biotype in this region.

Tapered implants have become routine for immediate implant placement after tooth extraction. It seemed extremely advantageous to use tapered implants in type 4 bone, where primary stability is difficult to achieve. The authors established a surgical implant placement protocol to be followed in areas where type 4 bone and a wide bone ridge (> or = 8 mm) are present. First, preparation of the implant alveolus is done exclusively with cylindric osteotomes, rather than with conic osteotomes or drills. The final cylindric osteotome is the same diameter as the final twist drill that is typically used in conventional preparation of the implant alveolus (a technique that can be adapted for use with other tapered implants). Because of the self-tapping property of the tapered implant used and its anatomic design, this surgical technique was developed to optimize the bone compaction effect in the coronal third of the implant, improving bone density and providing better primary stability values (> or = 70 ISO, via the Osstell Mentor device). With the strong bond that is created between the implant surface and the surrounding bone using this technique, immediate loading can be predictable, even in the type 4 bone that is commonly found in the maxillary tuberosity.