International Journal of Oral Implantology, 01/2008

Objectives: To evaluate which are the most effective procedures to maintain and recover soft tissue health around dental implants. Data sources: The Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE and EMBASE were searched with no language restriction up to June 2007. Handsearching included several dental journals, the bibliographies of the randomised controlled trials (RCTs) and relevant review articles. Review methods: RCTs comparing agents or interventions for maintaining or recovering peri-implant healthy tissues were eligible. Outcome measures were: implant failure, radiographic marginal bone level changes, changes in probing 'attachment' level, changes in probing pocket depth, marginal bleeding, plaque, side effects, ease of maintenance, patient satisfaction, cost, and treatment time. Screening of eligible studies, quality assessment and data extraction were conducted in duplicate. Authors were contacted for missing information. Results were expressed as random effect models using standardised mean differences for continuous data and relative risks for dichotomous data with 95% confidence intervals. Results: Eighteen RCTs were identified. Nine (238 patients) were included. Follow-ups ranged between 6 weeks and 1 year. No meta-analysis could be made since all trials tested different interventions. Listerine mouthwash showed a reduction of 54% in plaque and 34% in marginal bleeding compared with a placebo after 3 months. Conclusions: There was little reliable evidence for which are the most effective interventions for maintaining healthy peri-implant soft tissues. However, it should not be interpreted that current maintenance regimens are ineffective. There is a definite need for trials powered to find possible differences, using primary outcome measures and with much longer follow-up. Keywords: dental implants, maintenance, randomised controlled clinical trial, systematic review

Purpose: To evaluate the efficacy of prophylactic antibiotics for dental implant placement. Materials and methods: Twelve Italian private practices agreed to participate in this trial, each centre providing 30 patients. One hour prior to implant placement, patients were randomised, for consumption orally of 2 g amoxicillin or identical placebo tablets. Patients needing bone augmentation procedures were not included. Outcome measures were prosthesis and implant failures, adverse events and post-operative biological complications. Patients were seen 1 week, 2 weeks and 4 months post-operatively. Results: One centre did not deliver any data and 14 patients had to be excluded from the trial for various reasons. One hundred and fifty-eight patients were evaluated in each group and none dropped out at 4 months. Two prostheses and two implants failed in the antibiotics group, compared with four prostheses and nine implants in the placebo group. There were no statistically significant differences for prosthesis failures, implant losses, complications and side effects. Conclusions: No statistically significant differences were observed. However, four times more patients in the placebo group experienced implant failures than in the antibiotic group, and this requires further investigation. Keywords: amoxicillin, antibiotic prophylaxis, dental implants, multicentre randomised placebo-controlled clinical trial

Purpose: To evaluate the efficacy of immediate loading versus early loading at 6 weeks of bar-retained mandibular overdentures supported by two implants placed with a flapless technique. Materials and methods: Sixty patients were randomised: 30 to the immediately loaded group and 30 to the early loaded group. To be immediately loaded, implants had to be inserted with a minimum torque > 48 Ncm. Outcome measures were prosthesis and implant failures, biological and biomechanical complications, patient satisfaction, and Implant Stability Quotient (ISQ) assessed with a resonance frequency analysis instrument. Results: Sixty implants were placed in each group. Flaps had to be raised in nine patients to check drill direction or to better visualise the area after multiple teeth extraction. Two implants in two patients did not reach the planned insertion torque and were immediately replaced by larger diameters ones. After 1 year no drop out occurred and two early loaded implants failed in two patients. There were no statistically significant differences between groups for prosthesis failures, implant losses, complications, and mean ISQ values; however, patients in the immediately loaded group were significantly more satisfied than those loaded early. When comparing mean ISQ values taken 6 weeks after placement with 1-year data within each group, values decreased significantly. Conclusions: Mandibular overdentures can be successfully loaded the same day of implant placement with a minimally invasive surgery, increasing patient satisfaction while decreasing treatment time and patient discomfort. No apparent advantages were seen when loading the overdentures at 6 weeks. Keywords: dental implants, flapless, immediate loading, overdentures, randomised controlled clinical trial

Purpose: To evaluate the outcome of dental implants placed in partially edentulous patients with a history of severe periodontitis (SP), moderate periodontitis (MP) and no periodontitis (NP). Materials and methods: Sixty-two partially edentulous patients were consecutively enrolled in this study. Patients were divided into three groups according to their initial periodontal conditions, assessed with a modified Periodontal Screening and Recording (PSR) index: 26 patients were in the SP group, 7 in the MP group, and 29 in the NP group. Patients requiring periodontal treatment were treated prior to implantation. Various dental implants and procedures were used. In the SP group 129 implants were placed, 26 were placed in the MP group, and 72 in the NP group. Outcome measures were prosthetic success, implant survival, prevalence of peri-implantitis and mean peri-implant bone level changes on periapical radiographs. Results: Six patients dropped out, two from each group, at 5 years. Two implants and their prosthesis failed with peri-implantitis in one patient and two implants were successfully treated for periimplantitis in another patient in the SP group. After 5 years, patients affected by SP and MP lost on average twice the amount of peri-implant bone compared with healthy patients (2.6 mm versus 1.2 mm). This difference was highly statistically significant. Conclusions: Patients with a history of SP and MP lose more peri-implant bone than periodontally healthy patients and might be at higher risk for peri-implantitis and implant failures. Keywords: bone level, dental implant, peri-implantitis, periodontitis, prognosis

Aim: There are no published studies regarding sinus reactions to immediately loaded zygomatic implants. The aim of this study was to evaluate the maxillary sinus in a cohort of patients by means of clinical criteria and computerised tomography performed before surgery and after zygomatic implant placement (immediate function protocol). Materials and methods: A total of 36 patients with 71 immediately loaded zygomatic implants were evaluated to find clinical criteria of maxillary sinus disturbance 13 to 42 months (average 21.9 months) after zygoma implant placement. A total of 44 implants had a machined surface and 27 had a porous titanium oxide surface. Twenty-six patients with 52 immediately loaded zygomatic implants were evaluated by means of a CT scan of the paranasal sinuses, 3 to 20 months (average 10.5 months) after zygomatic implant placement. All patients had no sinus symptoms before surgery and had a preoperative CT scan. Results: No clinical signs or symptoms of sinusitis were found. Radiological opacity of the antrum was found in two sinuses (out of 52), and minimal thickening of the Schneiderian membrane was found in 12 patients (out of 26). In eight of them, this was present in the preoperative CT scan. Conclusions: Sinuses penetrated by zygomatic implants seem to maintain a normal physiology. However, in approximately 15 to 20% of patients, early radiological findings without clinical symptoms were observed. Keywords: complications, maxillary sinus, sinusitis, zygomatic implant

Aims: The aim of this case series was to evaluate the Procera Software v1.6 and the surgical templates for flapless implant placement and immediate loading in atrophic fully edentulous maxillae. Materials and methods: The Procera Software was used to plan the exact position of the implants, and surgical templates were made to guide flapless implant placement. To allow for immediate loading, implants had to be placed with an insertion torque > 30 Ncm. Provisional cross-arch prostheses, produced before surgery using the software planning, were delivered immediately after implant placement, and replaced by final restorations after 6 months. Outcome measures were: prosthetic and implant failures, complications, post-operative pain and swelling, consumption of analgesics, and patient satisfaction. The followup stopped at 8 months post-loading. Results: Thirteen consecutive patients with atrophic maxillae were treated with 89 implants (6 to 8 implants per patient). Two flaps had to be elevated in two patients. One template fractured during surgery. Three implants in two patients were not loaded immediately. In four patients, impressions had to be taken to fit the provisional prostheses onto the implants. Five implants failed in four patients. One patient dropped out, due to financial reasons, with the provisional prosthesis still in function. Eight months after loading, all prostheses were successful and 11 out of 12 patients reported their quality of life and lifestyle had improved. Conclusions: This software-based treatment planning may be useful in planning and treating challenging cases such as flapless implant placement and immediate loading of maxillary cross-arch bridges, but a learning curve is necessary. Keywords: case series, computer-guided surgery, edentulous maxilla, flapless procedure, immediate loading