Dentin dysplasia type I: a challenge for treatment with dental implants

<p>Abstract</p> <p>Background</p> <p>Dentin dysplasia type I is characterized by a defect of dentin development with clinical normal appearance of the permanent teeth but no or only rudimentary root formation. Early loss of all teeth and concomitant underdevelopment of the jaws are challenging for successful treatment with dental implants.</p> <p>Methods</p> <p>A combination of sinus lifting and onlay bone augmentation based on treatment planning using stereolithographic templates was used in a patient with dentin dysplasia type I to rehabilitate the masticatory function.</p> <p>Results</p> <p>(i) a predisposition for an increased and accelerated bone resorption was observed in our patient, (ii) bone augmentation was successful using a mixture of allogenic graft material with autogenous bone preventing fast bone resorption, (iii) surgical planning, based on stereolithographic models and surgical templates, facilitated the accurate placement of dental implants.</p> <p>Conclusion</p> <p>Bony augmentation and elaborate treatment planning is helpful for oral rehabilitation of patients with dentin dysplasia type I.</p

Does Apico-Coronal Implant Position Influence Peri-Implant Marginal Bone Loss? A 36-Month Follow-Up Randomized Clinical Trial

Purpose: Preserving peri-implant bone and reducing exposure of the rough implant surface might influence long-term outcomes of implant therapy. The aim of this study was to compare peri-implant clinical and radiologic parameters after crestal and subcrestal dental implant placement at 36 months’ follow-up. Materials and Methods: We carried out a randomized clinical trial involving partially edentulous patients in need of an implant-supported, partial fixed dental prosthesis or a single crown. Patients were randomized according to the implant insertion depth: implants placed approximately 2 mm below the bone crest (test group) or implants placed at bone crest level (control group). They were evaluated 6, 12, 24, and 36 months after prosthetic loading. Peri-implant marginal bone loss was the primary outcome, and the following secondary outcomes were registered: coronal bone changes, plaque index, probing depth, modified bleeding index, retraction and width of the peri-implant mucosa, and peri-implant health condition. Implant survival and success rates after 36 months’ follow-up were calculated. Results: The study comprised 128 patients (83 men and 45 women; mean age, 54.4 ± 12.2 years) and a total of 265 implants (133 in control group and 132 in test group). No statistically significant differences in the peri-implant clinical parameters were found. After 3 years’ follow-up, 53.4% of the crestal implants and 25.8% of the subcrestal implants presented marginal bone loss, with a mean exposed rough surface of –0.2 ± 0.3 mm and –0.09 ± 0.1 mm, respectively (P =.001). The overall success rate was 99.6%. Conclusions: Crestal and subcrestal implants showed similar clinical outcomes 3 years after prosthetic loading. Significant differences were observed in the radiologic parameters, showing less peri-implant marginal bone loss with subcrestal implants

Implant treatment in atrophic posterior mandibles: Vertical regeneration with block bone grafts versus implants with 5.5-mm intrabony length

Purpose: To retrospectively compare the outcomes of implants placed in posterior mandibles vertically regenerated with onlay autogenous block bone grafts and short dental implants. Materials and Methods: Consecutive patients with vertical bone atrophy in edentulous mandibular posterior regions (7 to 8 mm of bone above the inferior alveolar nerve) were treated with either implants placed in regenerated bone using autologous block bone grafts (group 1) or short implants (with 5.5-mm intrabony length) in native bone (group 2) between 2005 and 2010 and followed for 12 months after loading. The procedure used was the established treatment protocol for this type of patient at the Oral Surgery Unit (University of Valencia, Spain) at the time of surgery. All grafts were obtained using piezosurgery. The outcomes assessed were: complications related to the procedure, implant survival, implant success, and peri-implant marginal bone loss. Statistical analysis was done using the Fisher exact test and the Mann-Whitney test. Results: Thirtyseven patients were included, 20 (45 implants) in group 1 and 17 (35 implants) in group 2. In group 1, 13 implants were less than 10 mm long (2 were 7 mm and 11 were 8.5 mm), and 32 were 10 mm or longer; the diameter was 3.6 mm in 6 implants, 4.2 mm in 31, and 5.5 mm in 8. In group 2 all implants were 7 mm long; the diameter measured 4.2 mm in 14 implants and 5.5 mm in 21 implants. Complications related to the block bone grafting procedure were temporary hypoesthesia in one patient, wound dehiscence with graft exposure in three patients, and exposure of the osteosynthesis screw without bone graft exposure in one patient. After 12 months, implant survival rates were 95.6% in group 1 and 97.1 % in group 2; success rates were 91.1% and 97.1%, respectively. The average marginal bone loss was 0.7 ± 1.1 mm in group 1 and 0.6 ± 0.3 mm in group 2. Conclusions: When residual bone height over the mandibular canal is between 7 and 8 mm, short implants (with 5.5-mm intrabony length) might be a preferable treatment option over vertical augmentation, reducing chair time, expense, and morbidity

Implant abutment cleaning by plasma of argon: 5-year follow-up of a randomized controlled trial

Background: Contamination of implant abutments could potentially influence the peri-implant tissue inflammatory response. The aim of the present study is to assess the radiographic bone changes around customized, platform-switched abutments placed according to the ‘‘one-abutment-one-time’’ protocol, with and without plasma of argon cleaning treatment. Methods: Thirty healthy patients with thin gingival biotype (&lt;1 mm) and history of periodontal disease received one maxillary implant each. Immediately before abutment connection, patients were randomly assigned to control group (cleaning protocol by steaming) or test group (plasma of argon treatment). Outcome measures were: 1) success rate of implants and prostheses; 2) biologic and prosthetic complications; 3) peri-implant marginal bone loss (MBL); 4) esthetic and periodontal parameters; and 5) patient satisfaction. Results: Neither implants nor prostheses were lost in either group at the 5-year follow-up examination. Overall, both groups showed a slight amount of peri-implant bone loss from baseline to 5 years. A statistically higher mean MBL was found in the control group compared with the test group at 6, 24, and 60 months after crown connection. Nevertheless, during the entire follow-up period, intragroup comparison demonstrated statistically significant mean MBL in the control group, but not in the test group. The test group showed a higher mean gain at the soft tissue margin, but not for the papilla. All implants showed good periodontal parameters, with no significant differences between groups. Conclusion: Plasma of argon could be used to disinfect implant abutments before insertion to minimize future peri-implant bone resorptio

Impact of crestal and subcrestal implant placement upon changes in marginal peri-implant bone level. A systematic review

Background: To systematically assess studies analyzing peri-implant bone loss in implants placed in crestal and subcrestal position. Material and methods: Following the recommended methods for systematic reviews and meta-analyses (PRISMA), an electronic search was conducted in the PubMed (MEDLINE), EMBASE and LILACS databases to identify all relevant articles published up until April 2017. The search included human studies comparing marginal bone loss (MBL) between a control group and a study group with a minimum of 10 patients and a minimum follow-up of 6 months after prosthetic loading with rough neck implants. Two independent reviewers assessed the risk of bias in the selected studies based on the Newcastle-Ottawa scale for observational studies and the Cochrane Collaboration for clinical trials. Results: Of 342 potentially eligible items, 7 complied with the inclusion criteria. One article was retrieved through the manual search. Eight articles were finally included: five experimental and three observational studies. The risk of bias assessed by the Cochrane Collaboration and Newcastle-Ottawa showed a high risk of bias. The mean follow-up period was 21 months (range 6-36 months). In four studies, implants placed in a crestal position presented higher MBL than subcrestal implants - the differences being significant in one study, while in three studies, implants placed in a subcrestal position presented greater MBL than crestal implants, with significant differences in only one study. Conclusion: Despite its limitations, the present systematic review did not find better outcomes between crestal and subcrestal implant placement, however, new studies will be needed, involving improved designs and the standardization of protocols to allow statistical comparisons and the drawing of firm conclusions

Piezoelectric vs. conventional drilling in implant site preparation: Pilot controlled randomized clinical trial with crossover design

Objective: To compare implant stability throughout osseointegration, peri-implant marginal bone loss, and success rates of implants placed with conventional and mixed drilling/piezoelectric osteotomy. Materials and methods: A pilot randomized-controlled trial was performed on 15 patients. Each patient received two implants in the mandibular molar region. All sites were prepared with conventionally up to the 2.8 mm wide drill. Osteotomies were randomly finalized with a 3 mm diameter drill (control group) or with two consecutive ultrasonic tips (2.8 mm and 3 mm wide, respectively) (test group). Resonance frequency analysis measurements were taken at implant placement and after 1, 3, 8, and 12 weeks. Peri-implant marginal bone loss 12 months after loading was calculated using periapical radiographs. Wilcoxon test for related samples was used to study differences in implant stability and in peri-implant marginal bone loss between the two groups. Results: Twenty-nine of 30 implants osseointegrated successfully (one failure in the control group). Stability was significantly higher in the test group at the 8th week assessment; differences were non-significant at all other time-points. Longitudinally, differences were observed between the patterns of implant stability changes: in the test group stability increased more progressively, while in the control group an abrupt change occurred between the 8th and 12th weeks assessments. No difference was found in peri-implant marginal bone loss between the groups. All 29 implants were functionally successful at the 15-month visit. Conclusions: Within the limit of this pilot study (small sample size, short follow-up), data suggested that implant stability might develop slightly faster when implant site osteotomy is performed with a mixed drilling/ultrasonic technique