International Journal of Oral Implantology, 03/2009

Background: dental implants require sufficient bone to be adequately stabilised. For some patients implant treatment would not be an option without horizontal or vertical bone augmentation. A variety of materials and surgical techniques are available for bone augmentation. Objectives: to test whether and when augmentation procedures are necessary and which is the most effective technique for horizontal and vertical bone augmentation. Search methods: the Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE were searched. Several dental journals were hand searched. The bibliographies of review articles were checked, and personal references were searched. More than 55 implant manufacturing companies were also contacted. The last electronic search was conducted on 11 June 2009. Selection criteria: randomised controlled trials (RCTs) of different techniques and materials for augmenting bone horizontally and/or vertically for implant treatment that reported the outcome of implant therapy at least to abutment connection. Trials were divided into two broad categories: horizontal augmentation and vertical augmentation techniques. Data collection and analysis: screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted independently and in duplicate. Authors were contacted for any missing information. Results were expressed as random-effects models using mean differences for continuous outcomes and odds ratios (OR) for dichotomous outcomes with 95% confidence intervals (CI). The statistical unit of the analysis was the patient. Results: 13 RCTs out of 18 potentially eligible trials were suitable for inclusion. Three RCTs (106 patients) dealt with horizontal and 10 trials (218 patients) with vertical augmentation. Since different techniques were evaluated in different trials, only one meta-analysis could be performed. When comparing whether vertical augmentation procedures were more advantageous than short implants, a meta-analysis of two trials resulted in more implant failures OR = 5.74 (95% CI 0.92 to 35.82; borderline significance, P = 0.06) and statistically significantly more complications OR = 4.97 (95% CI 1.10 to 22.40) in the vertically augmented group. When comparing various horizontal augmentation techniques (three trials) no statistically significant differences were observed. When comparing various vertical bone augmentation techniques (eight trials) no statistically significant differences were observed except for three trials which showed that more vertical bone gain could be obtained with osteodistraction than with inlay autogenous grafts (mean difference 3.25 mm; 95% CI 1.66 to 4.84), and with bone substitutes rather than autogenous bone in guided bone regeneration (mean difference 0.60 mm; 95% CI 0.21 to 0.99) in posterior atrophic mandibles, and that patients preferred a bone substitute block over a block of autogenous bone taken from the iliac crest (OR = 0.03; 95% CI 0.00 to 0.64; P = 0.02). Conclusions: conclusions are based on few trials including few patients, sometimes having a short follow-up, and often being judged to be at high risk of bias. Various techniques can augment bone horizontally and vertically, but it is unclear which are the most efficient. Short implants appear to be a better alternative to vertical bone grafting of resorbed mandibles. Complications, especially for vertical augmentation, are common. Some bone substitutes could be a preferable alternative to autogenous bone. Osteodistraction osteogenesis allows for more vertical bone augmentation than other techniques, which, on the other hand, can allow for horizontal augmentation at the same time. Titanium screws may be preferable to resorbable screws to fixate onlay bone grafts. Keywords: autogenous bone, bone substitutes, randomised controlled clinical trial, systematic review

Purpose: This randomised double-blind placebo-controlled trial was carried out to investigate the effect of a one-week post-operative course of 600 mg of ibuprofen taken four times a day on marginal bone level around dental implants. Materials and methods: A total of 61 patients were allocated to the ibuprofen (31 patients) or placebo group (30 patients). Overall, 132 implants were inserted, 67 implants in the ibuprofen group and 65 implants in the placebo group. Preparation of the implant sites was carried out with an intermittent drilling sequence adapted to the fixture diameter and the local bone quality according to the Astra Tech implant installation guide. The primary outcome measure was the change in marginal bone level around dental implants from the baseline (2 weeks post-placement) to the 3- and 6-month radiographic examinations. The paralleling technique and a film holder coupled to a beamaiming device were used to take the periapical radiographs. Measurement of changes in bone level was made using a viewing box and ×8 magnifier. Results: Two patients from the ibuprofen group were unable to complete the prescribed course of ibuprofen owing to a minor self-reported stomach upset. A patient from the control group did not attend any of the scheduled appointments following implant placement. A total of three patients dropped out. All implants survived in either group during the 6-month observation period. The mean marginal bone level changes from the baseline were (-0.33 mm) at the 3-month and (-0.29 mm) at the 6-month follow-up for the ibuprofen group while the corresponding values for the placebo group were (-0.12 mm) and (-0.30 mm). There were no statistically significant differences between groups for mean marginal bone level changes at 3 months (P = 0.27) or 6 months (P = 0.97). Conclusions: Administration of a short course of systemic ibuprofen for post-operative pain management subsequent to implant placement may not have a significant effect on the marginal bone around dental implants in the early healing period. Keywords: dental implants, ibuprofen, marginal bone, periapical radiograph, placebo

Purpose: To evaluate the 10-year prognosis of consecutively endodontically treated or retreated teeth and to investigate some of the prognostic factors which could predict the long-term outcome of endodontic therapy. Materials and methods: This retrospective cohort study included any patient who had endodontically treated or retreated teeth from 1986 to 1998 by a single operator in a private practice. Outcome measures were clinical and radiographic success assessed by the operator, radiographic success assessed by an independent outcome assessor and complications evaluated 10 years after treatment. Descriptive statistics, life table, Kaplan-Meier and Cox regression analyses for success were fitted. Results: A total of 411 patients with 1175 endodontically treated teeth were identified. Ten years after treatment 102 patients (24.8%) with 223 (19.0%) teeth were lost at the follow-up. The number of teeth that were originally treated and retreated were 704 and 471, respectively. Thirty-two teeth (2.7%) had one complication, which was successfully treated. A total of 988 (84.1%) teeth were considered a complete success, 46 (3.9%) a partial success, 52 (4.4%) a partial failure and 68 (5.8%) had to be extracted according to the treating clinician. For 21 teeth (1.8%) there was no follow-up information. The radiographic healing of 1086 teeth was evaluated by an independent assessor: 980 (90.2%) showed complete healing, 52 (4.8%) improvement, and 54 (5.0%) no change or worsening. The life-table analysis showed 93% of teeth surviving at 10 years after endodontic treatment. There were no differences for survival rates between teeth treated for the first time and those that were retreated (Kaplan-Meier). Teeth retreated because of symptoms or for a periapical/lateral radiolucency were more likely to fail. Conclusions: Approximately 7% of endodontically treated teeth were extracted 10 years after treatment. Symptoms and radiolucency of teeth needing retreatment may be important predictors for failure. Keywords: apical periodontitis, epidemiology, longitudinal study, radiographic evaluation, retrospective evaluation, root canal treatment

Purpose: To evaluate aesthetic and patient satisfaction after tooth extraction using a bone substitute (and soft tissue grafting when tissue thickness was lacking) under a pontic to preserve the alveolar ridge for aesthetic purposes. The contralateral natural tooth acted as internal control. Materials and methods: All patients with at least one site under a pontic augmented with Bio-Oss® or Bio-Oss® Collagen with or without a concomitant connective tissue graft with at least a follow-up of 6 months after the ridge preservation procedure were eligible for the present retrospective study. Sites with a damaged buccal wall were excluded. Outcome measures were: aesthetics (pink esthetic score, PES) evaluated by an independent and blinded dental hygienist on the basis of clinical pictures, patient satisfaction, patient preference and complications. Results: Twenty-six patients were consecutively treated, and 23 patients attended the evaluation visit. In seven patients, soft tissue grafts were performed in conjunction with Bio-Oss placement. Eight to 86 months after the ridge augmentation procedure (mean 38 months), there were no statistically significant differences observed in PES between preserved sites and control teeth. Patient satisfaction did not show any statistically significant difference between the two groups either. All patients declared they would undergo the same procedure again. Conclusions: Bio-Oss placement in post-extractive sites with a remaining buccal bone plate lead to a good aesthetic result. Randomised clinical trials with suitable control groups are needed to identify the most effective techniques and/or materials to preserve ridges under pontics. Keywords: aesthetic, bone substitutes, observational study, pontic ridge preservation

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: bibliographic databases, literature searching