International Journal of Oral Implantology, 03/2008

Purpose: 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®) 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. Keywords: bone augmentation, bone grafting, bovine anorganic bone, dental implants, inlay graft, vertical augmentation

Purpose: To evaluate the efficacy of hyaluronic acid to improve the healing of surgical incisions in the oral cavity. Materials and methods: Six Italian private practices participated in this trial, each centre provided 12 patients. After suturing, patients were randomised to receive either a single application of 0.8% hyaluronic acid or a placebo (the carrier). Outcome measures were: assessment of wound healing 10 days post-operatively on a Likert scale by the blind operators and by an independent and blinded outcome assessor on the photographs, adverse events and post-operative complications. Reproducibility was assessed by evaluating agreement between operators and the independent outcome assessor using the weighted Kappa statistic. Results: Thirty-six patients were evaluated in each group, at ten days none had dropped-out. No post-operative complications or adverse events occurred. There were no statistically significant differences for wound healing, assessed clinically by the blinded operators or on photographs evaluated by a blinded and independent outcomes assessor. There was a substantial agreement between operators and the independent outcome assessor in the wound scoring. Conclusions: Hyaluronic acid placed over surgical incisions in the oral cavity does not appear to improve wound healing. Further trials are needed to better understand the potential role of hyalulonic acid in dental applications. Keywords: hyaluronic acid, multicentre randomised placebo-controlled clinical trial, oral cavity, wound healing

Aims: To compare immediate versus early (6 weeks) non-occlusal loading of dental implants placed flapless in partially edentulous patients 1 year after loading. Materials and methods: Sixty patients were randomised: 30 to the immediately loaded group and 30 to the early loaded group. In order to be immediately loaded, implants were inserted with a minimum torque of >=40Ncm. Implants were fully occlusally loaded after 6 months. Outcome measures were prosthesis and implant failures, and biological and biomechanical complications. Results: Five implants in five patients randomised to the immediately loaded group did not reach the required primary implant stability. Three of these implants (two prostheses) were not immediately loaded. Two patients who were randomised to the early loaded group were immediately loaded erroneously. Implants in five patients of the early loaded group were conventionally loaded. No patient dropped out and there were no failures. Two complications occurred in the early and one in the immediately loaded group (no statistically significant difference), but were solved. Conclusions: The use of a flapless technique for placing dental implants in conjunction with non-occlusal immediate or early loading in selected patients can provide excellent clinical results. No differences were observed when comparing implants that were loaded immediately or early. Therefore, when a high primary implant stability is obtained, it might be preferable to load the implants immediately rather than waiting for a few weeks. Keywords: dental implants, early loading, immediate loading, non-occlusal loading, partial edentulism

Objectives: The aim of this cohort study was to evaluate the safety and the acceptability of an electric toothbrush used on the peri-implant mucosa of implants placed in the aesthetic area. Methods: One hundred consecutive patients rehabilitated with implants positioned in the maxillary aesthetic area were recruited. Implants had to be restored at least 6 months prior to baseline. At baseline, subjects were provided with Oral-B Professional Care 7000 and received appropriate instructions to brush twice a day over a 12-month period. Papillary bleeding index, recession and probing depth were measured at baseline and at 3, 6, and 12 months. Results: Ninety-eight (98) patients completed the study. There was an overall reduction of recession (mean 0.2 mm) of borderline statistical significance. All of the changes occurred at the first followup visit (P=0.09) and persisted thereafter. The statistical analyses regarding the probing depth found a highly significant decrease over time (mean 0.3 mm). The bleeding score showed a gradual decrease over time, with a reduction at 12 months by more than half (0.65) in comparison with the baseline (1.50) and was shown to be highly significant (Wilcoxon sign-rank test: P0.001). No patient showed adverse effects such as ulcerations or desquamation. A high score of satisfaction by the patients using the electric toothbrush was reported (94% would continue to use it). Conclusion: The electric toothbrush Oral B Professional Care 7000 appears to be safe for patients with fixed prosthesis on implants in aesthetic areas. Successive randomised clinical trials are needed to compare this instrument with other therapeutic devices for mechanical plaque control. Keywords: electric toothbrush, implant, maintenance, peri-implant mucosa, powered toothbrush

Purpose: To evaluate, in a retrospective case series, survival rates and complications of Brånemark dental implants placed according to 'conventional' procedures in patients consecutively treated in a Swedish specialist private practice. Materials and methods: Eighty-three consecutively treated patients received 89 final fixed prostheses (31 mandibular and 58 maxillary) supported by 310 (101 mandibular and 209 maxillary) implants placed according to 'conventional' procedures, that is, no implants shorter than 10mm, no immediate post-extractive implants and no bone grafting procedures. In 70 patients, implants were left to heal submerged, whereas 13 patients were treated according to a one-stage procedure. All restorations (40 screw-retained cross-arch bridges, 32 screw-retained partial bridges and 17 cemented single crowns) were delivered about 2 (mandible) to 3 or 4 (maxilla) months after implant placement. Outcome measures were prosthesis success, implant survival and complications. Results: One year after implant placement, no patients had dropped-out. No prostheses or implants had failed and no biological or biomechanical complications had occurred. Conclusions: Brånemark BioHelix dental implants placed according to 'conventional' procedures in 'selected' patients provided excellent short-term results. Randomised clinical trials with suitable controls are needed to confirm these preliminary results. Keywords: dental implants, follow-up, implant survival, observational study

This section presents concise educational articles for practising dentists. The series aims to educate practitioners regarding statistics and methods of conducting and interpreting research. Keywords: education, evidence-based, outcome measures, randomised controlled clinical trial, statistical analysis, systematic review