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PURPOSE: To evaluate clinical safety and effectiveness of a novel calcium-incorporated titanium implant (Xpeed, MegaGen Implant Co. Limited, Gyeongbuk, South Korea). MATERIALS AND METHODS: Sixty patients were randomised to receive either 1 to 6 calcium-incorporated or control titanium implants in the maxilla according to a parallel group design at 2 different centres. Implants were submerged and exposed at 3 different endpoints in equal groups of 20 patients each at 12, 10 and 8 weeks, respectively. Within 2 weeks, implants were functionally loaded with provisional or definitive prostheses. Outcome measures were prosthesis failures, implant failures, any complications and peri-implant marginal bone level changes. RESULTS: Thirty patients received 45 calcium-incorporated implants and 30 patients received 42 control titanium implants. One year after loading, no drop-outs and no prosthesis or implant failures occurred. There were no statistically significant differences between groups for complications (P = 0.61; difference in proportions = -0.27; 95% CI -0.71 to 0.18) and mean marginal bone level changes (P = 0.64; mean difference -0.04 mm; 95% CI -0.22 to 0.13). CONCLUSIONS: Nanostructured calcium-incorporated titanium implants seem to be at least as effective and safe as conventional titanium implants.

OBJECTIVES: To evaluate whether 6.3 mm-long implants could be a suitable alternative to longer implants placed in vertically augmented atrophic posterior mandibles. MATERIALS AND METHODS: Sixty partially edentulous patients having 7 to 8 mm of residual crestal height and at least 5.5 mm thickness measured on CT scans above the mandibular canal were randomised according to a parallel group design either to receive 1 to 3 submerged 6.3 mm-long implants or 9.3 mm or longer implants (30 patients per group) placed in vertically augmented bone. Bone was augmented with interpositional an organic bovine bone blocks covered by resorbable barriers. Grafts were left to heal for 5 months before implant placement. Four months later, provisional acrylic prostheses were delivered, and were then replaced after another 4 months by definitive metal-ceramic prostheses. Outcome measures were prosthesis and implant failures, complications, and radiographic peri-implant marginal bone level changes. All patients were followed up to 3 years after loading. RESULTS: Four patients dropped out, two from each group. The augmentation procedure failed in two patients and only 6.3 mm-long implants could be inserted. There were no statistically significant differences for prosthesis and implant failures. Three prostheses could not be placed or had to be remade in the short implant group versus 4 prostheses in the augmented group. Two short implants failed versus 3 long implants, all in different patients. There were statistically significantly more complications in augmented patients (22 complications in 20 augmented patients versus 5 complications in 5 patients of the short implant group). Both groups gradually lost peri-implant bone in a statistically significant way at 4 months, and 1 and 3 years after loading. Three years after loading, patients of the short implant group lost an average of 1.24 mm of peri-implant bone compared with 1.76 mm in the long implant group. Short implants experienced statistically significantly less bone loss (0.52 mm; CI 95% 0.20 to 0.83, P = 0.002) than long implants. CONCLUSIONS: When residual bone height over the mandibular canal is between 7 and 8 mm, 6.3 mm short implants could be an interesting alternative to vertical augmentation since the treatment is faster, cheaper and associated with less morbidity. Longer follow-ups are needed to confirm these results.

PURPOSE: To compare the efficacy of two different techniques for maintaining the space beneath a maxillary lining lifted using a lateral window approach: rigid synthetic resorbable barriers versus granular anorganic bovine bone. MATERIALS AND METHODS: Ten partially edentulous patients having bilaterally 1 to 5 mm of residual bone height and at least 5 mm bone width below the maxillary sinuses, were randomised in a split-mouth study design, to receive a rigid Inion GTR Biodegradable Membrane System barrier without any graft on one side and 100% loosely packed granular Bio-Oss on the contralateral side following a lateral window, two-stage, sinus lift procedure. After 6 months, two or three implants were inserted at each side and submerged for 4 months. Implants were loaded with provisional acrylic prostheses and replaced, after 4 months, by definitive metal-ceramic prostheses cemented with provisional cement. Outcome measures were implant and prosthetic failures, any complication and peri-implant marginal bone level changes assessed by a blinded outcome assessor. All patients were followed up to 1 year after loading. RESULTS: One patient dropped out after implant placement. One distal implant failed at the Inion side just before delivery of the definitive prosthesis, which was cut and maintained as a single crown. Four complications occurred in three patients at Inion sites (two sinus lining perforations, one fracture of the ceramic cusp of the definitive prosthesis, one iatrogenic peri-implantitis) versus two complications at Bio-Oss sites (one sinus lining perforation and one iatrogenic peri-implantitis). There were no differences for failures or complications between groups; however, in one of the patients where a perforation occurred at the Inion site, at implant placement, the sinus was filled two-thirds with soft tissue and the site was retreated with Bio-Oss. There were no statistically significant differences in bone loss between groups. One year after loading, Inion sides lost an average of 1.5 mm of periimplant bone and Bio-Oss sides about 1.7 mm. CONCLUSIONS: A bone graft may not be needed to augment atrophic maxillary sinuses since it is sufficient to keep space with a rigid barrier; however, it may be simpler to fill sinuses with a bone substitute than positioning a rigid barrier to maintain space.

PURPOSE: To compare the effectiveness of two different techniques to lift the maxillary sinus via a crestal approach: the Summers versus the Cosci technique. MATERIALS AND METHODS: Fifteen partially edentulous patients missing bilaterally maxillary molars and/ or premolars having 4 to 7 mm of residual crestal height and at least 5 mm thickness below the maxillary sinuses measured on computed tomography scans were randomised to have implants placed in sinuses crestally lifted according to the Cosci or Summers technique with bone substitutes according to a split-mouth design. Implants were left to heal submerged for 6 months. Implants were loaded with acrylic provisional crowns/prostheses. Screw-retained definitive metal-ceramic prostheses were delivered 4 months after provisional loading. Outcome measures were prosthesis and implant failures, any complications, operation time, operator preference, and patient preference assessed 1 month after surgery and 1 month after delivery of the final prostheses by a blinded outcome assessor. All patients were followed up to 5 months after loading (1 year after implant placement). RESULTS: Nineteen study implants were placed according to each technique. No patient dropped out and no implant failed. No discomfort/complications occurred at sites treated with the Cosci technique whereas 12 patients reported discomfort during the augmentation procedure at the side treated with the Summers technique, this was statistically significant, and in one of these patients a perforation of the sinus membrane occurred. Postoperatively, headache was reported by nine patients and swelling occurred in three of these patients at the Summers treated sides. Statistically significantly less time was required to place implants according to the Cosci technique (33 versus 24 minutes, on average). The two operators and 14 out of 15 patients preferred the Cosci technique. CONCLUSIONS: Both crestal sinus lift techniques were successful but the Cosci technique required less surgical time, produced less intra- and postoperative morbidity and was preferred by patients.

To evaluate whether 7-mm-long implants could be an alternative to longer implants placed in vertically augmented posterior mandibles.Sixty patients with posterior mandibular edentulism with 7-8 mm bone height above the mandibular canal were randomized to either vertical augmentation with anorganic bovine bone blocks and delayed 5-month placement of ≥10 mm implants or to receive 7-mm-long implants. Four months after implant placement, provisional prostheses were delivered, replaced after 4 months, by definitive prostheses. The outcome measures were prosthesis and implant failures, any complications and peri-implant marginal bone levels. All patients were followed to 1 year after loading.One patient dropped out from the short implant group. In two augmented mandibles, there was not sufficient bone to place 10-mm-long implants possibly because the blocks had broken apart during insertion. One prosthesis could not be placed when planned in the 7 mm group vs. three prostheses in the augmented group, because of early failure of one implant in each patient. Four complications (wound dehiscence) occurred during graft healing in the augmented group vs. none in the 7 mm group. No complications occurred after implant placement. These differences were not statistically significant. One year after loading, patients of both groups lost an average of 1 mm of peri-implant bone. There no statistically significant differences in bone loss between groups.When residual bone height over the mandibular canal is between 7 and 8 mm, 7 mm short implants might be a preferable choice than vertical augmentation, reducing the chair time, expenses and morbidity. These 1-year preliminary results need to be confirmed by follow-up of at least 5 years.

Background Dental rehabilitation with conventional prostheses after microvascular jaw reconstruction is often unsuccessful because of the altered oral anatomy and the lack of adequate dentition for fixation. Purpose This retrospective study evaluated the long-term outcomes of patients who underwent jaws reconstruction with a fibula free flap and subsequent rehabilitation with implant-supported prostheses. Materials and methods In total, 21 patients were enrolled; 108 osseointegrated dental implants, positioned on 21 fibular free flaps were assessed. Follow-up examinations were performed according to a standardized protocol, including clinical and radiological evaluations. The mean follow-up after implant insertion was 90.2 (range, 20-204) months. Results The overall implant survival rate was 97.2% at the 12-month follow-up, 86.5% at 60 months, and 79.3% at 120 months. The rate of overall implant success was 95.4% at the 12-month follow-up, 73.5% at 60 months, and 64.7% at 120 months. Implant failure was more common in patients that had implants placed after they underwent radiation therapy. Peri-implantitis and mucositis were identified in 14.8% and 20.3% of surviving implants, respectively, at the 5- and 10-year follow-up. The risk of developing peri-implantitis was estimated to be higher (odds ratio = 1.5) for patients without connective tissue or skin grafts versus patients with one of them (18.2% vs 9.5%). Conclusions Long-term implant-related outcomes show that the survival rate of implants placed into the fibula is acceptable. Radiotherapy negatively impacts survival and success, in particular in the short and medium-term follow-up. Moreover, a relevant peri-implant bone resorption does occur over time and ultimately influences implants success, and it is mainly related to peri-implant gingival mucositis. In this regard skin or connective tissue grafts seem to offer an aid to manage this problem.

© 2018, by Quintessence Publishing Co. Inc. Zygomatic implant site preparation could be considered a challenging procedure because of the use of a very long twist drill that could sometimes be difficult to control due to the need for drilling the malar bone on an oblique surface. Ultrasound was recently suggested to achieve better control, but the specific long tips required are not readily available, and the elongated tip also tends to reduce the efficacy. This technical note describes a proposal of a novel computer-aided technique to simplify the procedure of zygomatic implant site preparation. This method uses a standard-length ultrasonic tip to prepare the crestal bone and the zygomatic bone in two individual steps. The desired implant trajectory can be achieved during preparation using a real-time tracking navigation system. The combined use of the navigation system and the ultrasonic tips could aid the surgeon, during the first steps, in achieving optimal control of the instruments employed for the implant site preparation and keeping the planned zygomatic implant position. If the efficacy of the procedure is confirmed through clinical trials, this technique could also contribute to reducing the invasiveness of the procedure, promoting a smaller flap, and reducing the soft tissue damage.

Background: This study evaluates implant-borne prosthetic rehabilitation of 10 totally edentulous atrophic maxillae after bone reconstruction with a titanium-mesh technique and particulate bone graft. Methods: Ten atrophic maxillae were reconstructed with 19 titanium meshes and particulate autologous-heterologous bone. Maxillae were rehabilitated at least 5 months, with placement of 67 implants connected to the prostheses after an additional 4 months of rehabilitation. Cases were evaluated retrospectively in terms of complication rates, particularly on the amount of mesh exposure, implant survival, and success rates at the end of follow-up. Results: In seven cases, two meshes were prematurely exposed (within 4 to 6 weeks), and five were exposed later (after 4 to 6 weeks). Only two of the later exposures extended >1 cm2. Nevertheless, reconstructions allowed implant placement and prosthetic rehabilitation in all cases. Two implants were lost before loading. After mean follow-up at 39.3 (20 to 56) months since prosthetic loading, all 65 implants were functional (100% implant survival), but 15 implants demonstrated a peri-implant mean bone resorption of 2.96 mm increased bone loss, yielding a cumulative implant success rate of 76.9%. No prosthetic problem was observed. Conclusions: Use of titanium mesh with particulate bone can be considered a valid option in reconstructing atrophic maxillae to allow for implant-borne prosthetic rehabilitation. A high level of dehiscence did not compromise final outcome.

Purpose A complete maxillectomy for neoplastic lesions leads to serious oral dysfunction. Zygomatic implants for fixed bridge support are considered beneficial for maxillary defects after tumor resection. Materials and Methods This clinical study examined the management of patients with different maxillary defect types who underwent delayed rehabilitation using zygomatic implants and immediate prosthetic loading. Virtual preoperative planning and intraoperative navigation were performed in all cases. Results Five patients were treated with this new method. The total number of zygomatic implants positioned was 17. Four patients had immediate loading of a fixed prosthesis and 1 had delayed loading. One patient had 1 failed implant. Conclusion The use of preoperative virtual surgical planning and an intraoperative navigation system allows the surgeon to achieve safer implant positioning in a complex anatomic site. A systematic bone defect classification was created and a specific treatment protocol is proposed for each type of defect.

To compare the efficacy, complications and patient preference of two different techniques for vertical bone augmentation of the posterior mandible: bone blocks harvested from the iliac crest versus anorganic bovine bone blocks (Bio-Oss(R)) were used as inlays. MATERIALS AND METHODS: Ten partially edentulous patients, requiring bilateral and vertical bone augmentation of the posterior mandible (having 5 to 7mm of residual crestal height and at least 5mm thickness above the mandibular canal to allow for implant placement) had their posterior mandibles randomly allocated to both interventions. Resorbable barriers were used to cover the grafts. After 4 months, implants were inserted, and after a further 4 months, provisional prostheses were inserted. Definitive prostheses were delivered 4 months later. Prosthesis and implant failures, the amount of vertically regenerated bone measured on computerised tomography (CT) scans, any complications, the time needed to fully recover mental nerve sensitivity and patient preference were all recorded. All patients were followed up for up to 1 month after the delivery of the final restorations. RESULTS: Up to 5 months post-loading no patients dropped out or were excluded. Both procedures obtained significant bone gain and achieved the desired results. Four months after grafting, autogenous bone loss was on average 1.1mm (P=0.088) and Bio-Oss 0.6mm (P=0.001). There were no statistically significant differences in bone gain and maintenance among the two procedures. The sides treated with Bio-Oss recovered their full mental nerve sensitivity significantly faster than those treated with autogenous bone (4 versus 6.3 days). Three complications occurred during graft healing; two in the autogenous bone group and one determining the complete failure of the augmentation procedure. No implants or prosthesis could be placed in the planed area. There was no statistically significant differences in the occurrence of complications between the procedures. After implant placement one complication occurred in the autogenous bone group (probably as a consequence of a previous complication). Patients significantly preferred the treatment with Bio-Oss: 3 weeks after augmentation seven patients preferred Bio-Oss and three patients found the treatments to be 'equally good' (odds ratio 0.045 [5% confidence interval (CI) 0.00 to 0.87], P=0.04). One month after delivery of the final prostheses, eight patients preferred Bio-Oss and two patients found the treatments to be 'equally good' (odds ratio 0.03 [95% CI 0.00 to 0.64], P=0.02). CONCLUSIONS: This pilot study suggests that it might be sensible to use Bio-Oss blocks rather than bone harvested from the iliac crest as the interpositional graft in the treatment of resorbed posterior mandible, as patient discomfort is reduced.

PURPOSE: To evaluate whether 7-mm-long implants could be a suitable alternative to longer implants placed in vertically augmented bone for the treatment of atrophic posterior mandibles. MATERIALS AND METHODS: Sixty partially edentulous patients having 7 to 8 mm of residual crestal height and at least 5.5 mm thickness measured on a computed tomography scan above the mandibular canal were randomised to receive either two to three submerged 7-mm-long NanoTite External Hex implants (Biomet 3i) or 10-mm or longer implants (30 patients per group) placed in vertically augmented bone. Bone was augmented with anorganic bovine bone blocks (Bio-Oss) using a sandwich technique and resorbable barriers. The grafts were left healing for 5 months before placing the implants, which were submerged. Four months after implant placement, provisional acrylic prostheses were delivered. Definitive screw-retained metal-ceramic prostheses were delivered 4 months later. Outcome measures were: prosthesis and implant failures, any complications, and time needed to fully recover mental nerve sensitivity. All patients were followed up to the delivery of the final restorations (4 months after loading). RESULTS: No patient dropped out. In two patients of the augmented group, there was not enough space to place 10-mm or longer implants as planned and 7-mm-long implants were used instead. The most likely reason for this is that the Bio-Oss blocks fractured in many pieces at placement. One prosthesis could not be placed when planned in the 7-mm group versus three prostheses in the augmented group, because of failure of one implant in each patient. The difference was not statistically significant. All implants were successfully replaced and final prostheses delivered. Four complications (wound dehiscence) occurred during graft healing in the augmented group (one possibly associated with the failure of one implant) versus none in the 7-mm-long implant group. The difference was not statistically significant. No patient suffered from permanent paraesthesia of the alveolar inferior nerve; however, sensitivity was recovered significantly faster in the short implant group. CONCLUSIONS: The early results of this study suggest that, when the residual bone height over the mandibular canal is between 7 and 8 mm, 7-mm short implants might be a preferable choice since the treatment is faster, cheaper and associated with less morbidity than vertical bone augmentation. These preliminary results must be confirmed by follow-ups of 5 years or more in order to monitor the performance of short implants over time