European Journal of Oral Implantology最新文献

Purpose: To present a case report of autogenous transplant of two impacted mandibular canines.

Materials and methods: A 12-year-old girl, with vestibular impaction of mandibular left and right canines had them extracted and transplanted in the anatomically corrected sites, after an unsuccessful orthodontic treatment including surgical exposure.

Results: After 2 years the teeth are stable and their vitality is maintained.

Conclusions: In this case the transplantation of the mandibular canines was successful and maintained the vitality of the transplanted teeth for at least 2 years. By preserving the periodontal ligament is it possible to re-establish a functional tooth unit, which allows a physiologic growth of the jaws.

This section presents a brief review of articles on dental implants considered of special interest for the reader, in order to encourage the developing of research, the interest for data analysis and the attention to scientific publications. Your comments are welcome. Please contact Dr Michele Nieri at michelenieri@gmail.com.

Purpose: To present a case of a woman referred for the management of displacement of one implant in her right posterior mandible that had occurred three days previously.

Materials and methods: After implant placement, the practitioner was no longer able to detect the implant and inserted a second one at the same site without taking a control radiograph. At the end of surgery, when a radiograph was finally taken, the first implant appeared displaced into the mandible body. The patient suffered total paresthesia on the right lower lip and chin. A flap was raised and bone osteotomies were performed on the lateral side of the mandible to create a rectangular cortical bone window that was removed. The implant was stuck by the second implant placed coronally, and only after unscrewing this second implant was it possible to remove the first one.

Results: After 18 months, the patient recovered full sensitivity.

Conclusions: In cases of implant displacement, it is always recommended that appropriate radiographs are performed to visualise where the implants could have been displaced in order to avoid more serious consequences.

Aim: In this systematic review, we aimed to assess the impact of endosseous implants on the formation of an osteonecrosis of the jaw, as well as implant survival rates for patients under bisphosphonate (BP), antiresorptive and radiation therapy.

Materials and methods: An electronic search was performed using PubMed, Embase, and Medline databases with the logical operators: "dental implant", "antiresorptive", "bisphosphonate", "irradiation", "radiotherapy", "radiation", "necrosis" and "survival". The search was limited to articles published up to 15 December 2016. Recent publications were also searched manually to find any relevant studies that might have been missed using the search criteria noted above. The outcome variables were the implant survival rate and the frequency of osteonecrosis of the jaws.

Results: In total, 18 studies addressing oral implants in patients with BP or antiresorptive therapy and 23 with radiation therapy met the inclusion criteria and were included in this systematic review. Most of the studies had a retrospective design with a level of evidence (LoE) of III (moderately high risk of bias). Implant survival rate ranged from 92.86% to 100% in patients with BP/antiresorptive therapy (all due to osteoporosis) and 38.5% to 97.9% in patients with radiation therapy. For BP patients, osteonecrosis in relation to oral implants more frequently occurred in patients taking BPs due to malignant diseases. In patients with radiation therapy, an "implant triggered" necrosis is also a potential complication. The lack of data in the current literature concerning this issue does not allow a proper risk assessment to date.

Conclusions: Within the limits of this systematic review, implant treatment concepts seem to be a valuable approach in patients with radiation therapy and patients with BP therapy due to an osteoporosis. In patients taking BPs due to a malignant disease, implant treatments are not recommended due to the high number of reported implant-related necrosis in this patient cohort. Outcomes of this review should, however, be regarded with caution due to the low level of evidence of the currently existing data.

Purpose: To evaluate whether 6 mm long × 4 mm wide dental implants could be an alternative to implants of at least 10 mm long placed in bone augmented with bone substitutes in posterior atrophic jaws.

Materials and methods: A total of 20 patients with bilateral atrophic mandibles, and 20 patients with bilateral atrophic maxillae, having 5 mm to 7 mm of bone height below the maxillary sinus or 6 mm to 8 mm above the mandibular canal, had their side of the jaws randomly allocated according to a split-mouth design. They were allocated to receive one to three 6 mm long × 4 mm wide implants, or implants of at least 10 mm long in augmented bone by two different surgeons at different centres. Mandibles were vertically augmented with interpositional equine bone blocks and resorbable barriers, and implants were placed 3 months later. Maxillary sinuses were augmented with particulated porcine bone via a lateral window and implants were placed simultaneously. After 4 months, all implants were submerged and loaded with provisional prostheses. Four months later, definitive prostheses were delivered. Outcome measures were prosthesis and implant failures, any complication and radiographic peri-implant marginal bone level changes.

Results: Five patients (three treated in mandibles and two in maxillae) dropped out before the 3-year post-loading follow-up. Two short maxillary implants affected by peri-implantitis failed together with their prosthesis vs three mandibular prostheses that could not be placed on implants at least 10 mm long due to graft failures; one was associated with the loss of three implants because of infection. There were no statistically significant differences in implant (difference in proportions = 0.000; 95% CI: -0.140 to 0.140; P = 1.000) and prosthesis failures (difference in proportions = 0.057; 95% CI: -0.094 to 0.216; P = 0.625). In total, 18 complications occurred in 13 patients at augmented sites vs four complications in three patients with 6 mm long implants. Significantly more complications occurred at grafted sites in mandibles (difference in proportions = 0.353; 95% CI: 0.005 to 0.616; P = 0.031), but not in maxillae (difference in proportions = 0.222; 95% CI: -0.071 to 0.486; P = 0.219). In mandibles, patients with 6 mm long implants lost an average of 1.25 mm of peri-implant bone at 3 years vs 1.54 mm in patients with implants of at least 10 mm long. The difference was statistically significant (mean difference = 0.29 mm; 95% CI: 0.08 to 0.51 mm; P = 0.010). In maxillas, patients with 6 mm-long implants lost an average of 1.28 mm of peri-implant bone at 3 years vs 1.50 mm in patients with implants of at least 10 mm long. The difference was statistically significant (mean difference = 0.22 mm; 95% CI: 0.08 to 0.35 mm; P = 0.003).

Conclusions: Results at 3 years after loading indicate that 6 mm long implants with a conventional diameter of 4

Purpose: To evaluate the effect of sub-mucosal mechanical instrumentation following supra-mucosal plaque removal in the treatment of peri-implant mucositis.

Materials and methods: A total of 44 patients, 27 from a specialist clinic in Sweden, and 17 from a Japanese one, were included. The 44 patients had a total of 175 implants of which 84 (48%) had clinical signs of mucositis (bleeding on probing [BoP]) and no radiographic bone loss. At baseline, the 44 patients received professional supra-mucosal plaque removal and oral hygiene instruction and motivation. Following the 1-month examination, sub-mucosal instrumentation was initiated using ultrasonic and hand instruments. Patients were then examined at 4 and 7 months. Presence of plaque, marginal bleeding, BoP and probing pocket depth (PPD) changes were recorded at each examination in an unblinded manner.

Results: One month following supra-mucosal plaque removal, the number of treated implants with BoP was reduced from 84 to 44 (48% reduction) with a concomitant decrease of the mean PPD of 0.6 mm (95% CI: -0.5 to -0.7), from 4.4 ± 1.0 mm (mean ± SD) to 3.8 ± 1.0 mm, P < 0.0001. Following sub-mucosal instrumentation, a further reduction of 9% (from 44% to 36%) of BoP was recorded, with a concomitant reduction of the mean PPD of 0.3 mm (95% CI: -0.1 to -0.4) at the 7-month examination.

Conclusions: The improvement of the clinical condition (absence of marginal bleeding, BoP and PPD reduction at treated implants) following non-surgical treatment of mucositis appeared to be in great part because of supra-mucosal plaque removal, while the sub-mucosal instrumentation seemed to have only a minor additional effect. Deep implant position compared to neighbouring teeth/implant was associated with persisting mucositis following treatment. The presence of deep pockets following treatment was associated with BoP, screw-retained prostheses without abutment and sub-mucosal crown margins.

Purpose: To compare the clinical outcome (in particular of marginal peri-implant bone level changes) between immediately loaded straight implants which had definitive abutments placed at implant placement and never removed versus implants which had no intermediate abutments.

Materials and methods: Thirty-two edentulous patients had one of their jaws rehabilitated with a provisional screw-retained resin reinforced cross-arch fixed prosthesis supported by four immediately loaded implants: two central straight implants and two either tilted or straight distal implants. The two central straight implants were randomly allocated in two equal groups to receive or not an intermediate abutment (Multi-Unit Abutment, MUA) according to a parallel group design. To be immediately loaded implants had to be inserted with a minimum torque of 30 Ncm, which was achieved by all implants. After 4 months, definitive screw-retained metal-ceramic prostheses were delivered and patients were followed-up to 5 years after loading. Prostheses were removed every 8 months to facilitate professionally delivered maintenance. Outcome measures were prosthesis and implant failures, complications, peri-implant marginal bone level changes and bleeding on probing (BoP).

Results: Five-years after loading one patient dropped out from each group. No implant or prosthetic failure occurred. Three patients of the abutment group versus one of the no-abutment group were affected by complications (risk difference = 0.125; 95% CI: -0.13 to 0.37; Fisher exact test, P = 0.600). At 5 years, both groups lost marginal bone in a statistically significant way (0.32 ± 0.40 mm for patients of the abutment group and 0.35 ± 0.29 mm for patients of the no-abutment group), with no difference in bone loss between groups at patient levels (difference = 0.03 mm; 95% CI: -0.23 to 0.29 mm; P = 0.809). At 5 years, BoP was significantly higher in the no-abutment group than in the abutment group (difference between medians = 25%; 95% CI: 12.5% to 25%; P < 0.001). By considering only the average of the two central study implants per patient with and without intermediate abutments, there were no differences in bone loss (difference: -0.05 mm; 95% CI: -0.41 to 0.31 mm; P = 0.763), while marginal bleeding was significantly higher in the no-abutment group (difference between medians = 25%; 95% CI: 0% to 50%; P = 0.004).

Conclusions: The present results suggest that intermediate abutments may not be needed at immediately loaded cross-arch screw-retained prostheses, unless there is the necessity to correct implant angulation.

Purpose: To compare the outcome of immediately loaded and one-stage conventionally loaded variable-thread tapered implants in the posterior maxilla.

Materials and methods: This study was designed as a split-mouth randomised controlled trial. Twenty-six patients missing teeth bilaterally in the posterior maxilla received three to four implants in each of the posterior sextants. Bone quality was recorded based on Misch criteria (D1-D4) and insertion torque values were measured using a manual wrench. The implants on one side were immediately loaded with a temporary resin fixed partial denture on definitive multi-unit abutments. The implants in the contralateral side received definitive multi-unit abutments according to the one-stage unloaded protocol. Three to 3.5 months following implant placement, the implants were restored with metal-ceramic fixed prostheses. Outcome measures were implant and prosthesis failure rates, complications, and peri-implant bone level changes at 1 year following delivery of the definitive prostheses.

Results: Two patients dropped out prior to the delivery of definitive prostheses. Four implants supporting a four-unit immediately loaded prosthesis failed in one patient, 3 months following delivery of the definitive prostheses. None of the conventionally loaded implants or prostheses failed. There were no significant differences in the proportions of implant and prosthesis failures (difference = 4.2%; 95% CI -4.2 to 12.6%; P = 0.999). In the immediately loaded group, four early prosthetic complications occurred during the provisionalization phase (three small resin chippings and one prosthetic screw loosening). No other complications were reported. The difference in the rate of complications between the two interventions was not statistically significant (difference = 16.7%; 95% CI -1.2% to 35.6%; P = 0.125). The 1-year peri-implant marginal bone level changes were evaluated in 23 patients (77 immediately loaded and 76 conventionally loaded implants). On average, patients lost 0.42 mm at the immediately loaded and 0.46 mm at the conventionally loaded implants, the difference being statistically not significant (difference = 0.044 mm; 95% CI -0.27 to 0.18 mm; P = 0.701).

Conclusions: Immediate loading of 3- to 4-unit fixed partial prostheses supported by variable-thread implants in the posterior maxilla can yield good and similar 1-year results to one-stage conventionally loaded implants.