Machined Versus Cast Abutments for Single Dental Implants: A 3-year within-Patient Multicentre Randomized Controlled Trial

PURPOSE: To compare clinical outcomes of machined titanium abutments (machined group) versus cast cobalt-chrome abutments (cast group). MATERIALS AND METHODS: Thirty-one partially edentulous subjects received two single non-adjacent implant-supported crowns each at three centres. Three and a half months after implant placement, implants were randomized at impression taking to receive one machined and one cast abutment according to a within-patient study design. Four patients dropped out and one patient lost one implant before randomization, so only 26 patients had their implants randomized. Outcome measures were: prosthesis and implant failures, any complications, and radiographic peri-implant marginal bone level changes. Patients were followed up for 3 years after loading. RESULTS: After randomization, three patients dropped out. One implant failed and two crowns on cast abutments were lost, but differences in implant and prosthesis failures were not statistically different (McNemar test P = 1.000; difference in proportions = 0.04 and P = 0.500; difference in proportions = 0.08, respectively). Two minor complications occurred in the cast group versus one in the machined group, the difference not being statistically different (McNemar test P = 1.000; difference in proportions = 0.04; 95% CI 0.18 to 22.06). Both groups presented statistically significant peri-implant marginal bone loss from implant placement to 3 years after loading, respectively -0.72 ± 0.90 mm (P = 0.001) for machined and -0.60 ± 0.61 mm (P <0.001) for cast abutments, with no statistically significant differences between the two groups (mean difference -0.12 mm; 95% CI -0.57 to 0.34; P = 0.624). Both groups gradually lost marginal peri-implant bone from loading (baseline) to 3 years after loading, but this was not statistically significant; machined lost -0.05 ± 0.12 mm while cast lost -0.14 ± 0.11 mm, a difference that was not statistically significant (mean difference 0.06 mm; 95% CI -0.24 to 0.35; P = 0.708). CONCLUSIONS: The present clinical data suggest that implant prognosis up to 3 years after loading is not affected by the choice of machined or cast abutments

Natural or Palatal Positioning of Immediate Post-extraction Implants in the Aesthetic Zone? Five-year Outcomes of a Multicentre Randomised Controlled Trial

PURPOSE. To evaluate whether there is a difference in aesthetic outcomes when positioning immediate post-extractive implants in the “central” position (where the natural tooth would be in relation to adjacent teeth/implants) as opposed to roughly 3 mm more pala-tally. MATERIALS AND METHODS. Just after tooth extraction, 20 patients requiring one single immediate maxillary post-extraction implant, from second premolar to second premolar, were randomly allocated to receive one implant positioned in either the natural “central” position (central group; 10 patients), or about 3 mm more palatally (palatal group; 10 pa-tients) according to a parallel-group design at two different centres. When needed, sites were reconstructed, and bone-to-implant gaps were filled with granules of anorganic bovine bone and covered by resorbable collagen barriers. Implants were left submerged for 4 months and rehabilitated with provisional crowns, replaced after 4 months by definitive metal-ceramic crowns. Patients were followed up to 5 years after loading. Outcome measures were: crown and implant failures; complications; aesthetics, assessed using the pink aesthetic score (PES); peri-implant marginal bone level changes; and patient satisfaction, recorded by blinded assessors. RESULTS. Three patients from each group dropped out within 3 years after loading. Five years after loading, there were no significant differences between the two groups in median PES score, assessed by a blind assessor, (central: 10 [IQR: 5.5], palatal: 8.5 [IQR: 6.75], median difference =-1.0; 95% CI:-7.0 to 4.0; P = 0.571); median bone level (central: 0.45 mm [IQR: 1.76], palatal: 0.45 mm [IQR: 1.93], median difference = 0 mm; 95% CI:-1.7 to 3.0; P = 1.000); bone level changes (central: 0.15 mm [IQR: 0.70], palatal:-0.05 mm [IQR: 1.23], median difference =-0.20 mm; P = 0.471); implant failures (one in each group, 14%, difference in proportion = 0.00; 95% CI:-0.39 to 0.39; P = 1.000); or complications (two palatal group patients and one central group patient, difference in proportion = 0.14; 95% CI:-0.28 to 0.52; P = 1.000). Furthermore, patients from both groups were equally satisfied with both function and aesthetics (both P = 0.699). CONCLUSIONS. These preliminary results suggest that positioning of immediate post-ex-traction implants 3 mm more palatally may not, in fact, improve aesthetics; however, the sample size of the present study was very limited, and larger trials are therefore required to confirm or refute these findings

Machined Versus Cast Abutments for Dental Implants: a 1-year Within-patient Multicentre Randomized Controlled Trial Assessing Marginal Seal Capacity and Outcomes

PURPOSE To compare clinical outcomes of machined titanium abutments (machined group) versus cast cobalt-chrome abutments (cast group) and to evaluate in vitro their implant fit. MATERIALS AND METHODS This study comprised two parts. In the in vitro part, the im-plant–abutment fit of 5 cast abutments and 5 machined abutments screwed on with a torque of 30 Ncm was qualitatively and quantitatively evaluated using micro-computed tomography (µ-CT) and AgNO3 to reveal connection gaps. In the clinical part, 31 partially edentulous subjects received two single non-adjacent implant-supported crowns at three centres. At impression taking, three and a half months after implant placement, implants were randomized to receive a machined or cast abutment according to a wi-thin-patient study design. Unfortunately, four patients dropped out and one patient lost one implant before randomization, so only 26 patients had their implants randomized. Outcome measures were: prosthesis and implant failures, any complications, and radiographic peri-implant marginal bone level changes. Patients were followed up to 1 year after loading. RESULTS The fit of the implant–abutment connection was assessed in vitro using µ-CT scans. No gaps were revealed at any of the machined or cast abutments tested. In the clinical part, after randomization, three patients dropped out, no implant failed, but one crown on a cast abutment was replaced. The between-group difference in prosthesis failure was not statistically different (McNemar chi-square test P = 1.0; difference in proportions = 0.039). One complication occurred in each group, the difference not being statistically different (McNemar test P = 1.000; difference in proportions = 0; 95% CI 0.06 to 15.99). Both groups presented statistically significant peri-implant marginal bone loss from implant placement to 1 year after loading, respectively-0.76 ± 1.01 mm for machined and-0.69 ± 0.82 mm for cast abutments, with no statistically significant differences between the two groups (mean difference 0.07 mm; 95% CI-0.54 to 0.67; P = 0.828). Both groups gradually lost marginal peri-implant bone from loading to 1 year after loading but this was not significantly different, respectively-0.06 ± 0.56 mm for machined and-0.10 ± 0.29 mm for cast abutments, with no statistically significant differences between the two groups (P = 0.739; mean difference 0.07 mm; 95% CI-0.12 to 0.16; P = 0.739). CONCLUSIONS Our clinical data suggests that implant prognosis up to 1 year after loading is not affected by using machined or cast abutments. In support of these findings, in vitro analysis proved that both types of abutments allow a tight fit with no gaps. The-refore, for the time being dentists should feel free to choose whichever type they prefer. However, these preliminary results need to be confirmed by larger trials with at least 10 years of follow-up

To Splint or Not to Splint Short Dental Implants Under the Same Partial Fixed Prosthesis? One-year Post-loading Data From a Multicentre Randomised Controlled Trial

PURPOSE. To compare the clinical outcomes of two adjacent 6-mm-long dental implants splinted under the same prosthesis (control group) versus two identical implants sup-porting single crowns (test group). MATERIALS AND METHODS. Forty-seven patients with edentulous posterior (premolars and/or molars) jaws received two adjacent 6-mm-long dental implants, which were sub-merged. Four months later, at impression taking, patients were randomised to receive splinted or unsplinted definitive cemented metal-composite prostheses. Unfortunately, four patients died before randomisation and three patients lost five implants, so only 40 patients were randomised, according to a parallel-group design, to have both implants splinted under the same partial fixed prosthesis (19 patients) or with two single crowns (21 patients). Outcome measures were: prosthesis and implant failures, any complica-tions, peri-implant marginal bone level changes and patient satisfaction. Patients were followed-up to 1 year after loading. RESULTS. One patient from the splinted group dropped out. No implant failures occurred after randomisation. One complication occurred in the unsplinted group versus no complications at splinted implants, the difference not being statistically different (Fisher’s exact test P = 1.000; difference in proportions =-0.04; 95% CI-0.16 to 0.09). Both groups presented significant peri-implant marginal bone loss at 1 year after loading (P<0.05), respectively-0.36 (0.45) mm at splinted implants and-0.17 (0.31) mm at unsplinted implan-ts, but there were no statistically significant differences between the two groups (mean difference 0.19 mm; 95% CI-0.10 to 0.48; P = 0.194). All patients were fully or reasonably satisfied with the treatment, with the exception of two patients, both from the splinted group: one patient was not sure about the aesthetics, and another would not undergo the same treatment again. CONCLUSIONS. The present data seems to suggest that up to 1 year after loading the prognosis of short implants, mostly placed in mandibles characterised by dense bone quality, may not be influenced by splinting or not under the same fixed prostheses. Howe-ver, these preliminary results need to be confirmed by larger trials with follow-ups of at least 5 years

Comparison Between Single Early-loaded Implants With Sandblasted Acidetched (Sa) Surface Versus Sa Surface Modified With Ph Buffering Agent (Soi): Four-month Data From a Split-mouth, Multicentre Randomized Controlled Trial

PURPOSE. To compare implant survival and success rates and implant stability quotient (ISQ) values of early-loaded single implants with sandblasted acid-etched (SA, control group) surface versus implants with SA surface modified with pH buffering agent (SOI, test group). MATERIALS AND METHODS. This study was designed as multicentre, split-mouth, randomized controlled trial to evaluate implant and prosthesis survival rates, complications, and implant stability quotient (ISQ) in any partially edentulous subject requiring at least two single implant-supported crowns. A one-stage implant placement procedure was used, and implants were randomized after implant site preparation. ISQ values were eva-luated for each implant, at baseline and then every week up to 8 weeks after surgery, and finally at definitive crown delivery (12 weeks after implant placement). RESULTS. Overall, 62 patients from 9 centres were enrolled in this study. One patient dropped out from the study at 8 weeks. In the first 12 weeks of observation, 2 implants failed, both in the SA group, the difference not being statistically significant (P = 0.5). No prosthesis failure occurred up to 4 months after fitting. Five complications were expe-rienced, 3 in the SA group and 2 in the SOI group. The difference between groups was not statistically significant (OR = 0.66, 95% CI: 0.11 to 4.07; P = 0.650). Of these complications, loss of stability without rotation was observed in 2 implants from the SOI group and 2 implants from the SA group, all in the third and fourth weeks of measurements. All the implants were submerged and successfully osseointegrated at the twelfth week. The last complication was an SA implant screw loosening, which was resolved chair-side. The baseline mean ISQ values were 76.57 ± 7.54 (95% CI 74.69 to 78.44) in the SA group and 75.92 ± 7.69 (95% CI 73.89 to 77.73) in the SOI group. The mean ISQ values at 12 weeks were 79.17 ± 7.83 (95% CI 77.03 to 81.29) and 78.82 ± 8.80 (95% CI 76.42 to 81.21) in the SA and SOI groups, respectively. Mixed-effects modelling revealed a statistically significant difference between groups over time, with slightly lower ISQ values for the SOI group (-0.65; 95% CI-1.14 to-0.15). Statistically significant differences were also estimated among centres (P <0.001). CONCLUSIONS. Within the limitations of the present preliminary report, it is possible to conclude that both implants can be successfully loaded early

Brevi riflessioni in tema di sostanziale disconoscimento del diritto costituzionale d\u2019asilo nella recente giurisprudenza di legittimit\ue0

La finalit\ue0 del presente lavoro \ue8 duplice. Anzitutto si tenter\ue0 di evidenziare l\u2019insieme dei presupposti e delle condizioni per azionare il diritto d\u2019asilo costituzionale e quella fitta rete di tutele dello \u201cstraniero che fugge\u201d prevista dall\u2019ordinamento positivo. Si analizzer\ue0, successivamente, il percorso seguito dalla giurisprudenza di legittimit\ue0 che, nella colpevole e perdurante inerzia del legislatore, ha provato a dare applicazione all\u2019art. 10, comma 3, della Costituzione. In conclusione si prover\ue0 a rispondere alla domanda se, ad oggi, il diritto costituzionale di asilo abbia ancora margini di espansione o se, come ritiene la Cassazione, esso sia gi\ue0 stato \uabpienamente attuato\ubb

Dental implants treatment outcomes in patient under active therapy with alendronate: 3-year follow-up results of a multicenter prospective observational study

Objective: To evaluate the 3-year clinical and radiographic data of fixed implant-supported dental prosthesis delivered to patients having taken alendronate 35–70 mg weekly for at least 3 years before implant placement. Materials and Methods: Forty consecutive patients treated with oral bisphosphonates and requiring an implant-supported restoration were recruited in two private centers between January 2008 and December 2011. Implants were inserted through minimally invasive approach under antibacterial and antibiotic treatment, 6 months after alendronate administration stopping. After 4 months of submerged healing, implants underwent prosthetic loading. Hygiene maintenance and clinical assessments were scheduled every 4 months for 3 years. Outcome measures were the following: implant and prosthetic success, survival rates, any observed clinical complications, marginal bone remodeling, probing pocket depth and bleeding-on-probing. Results: At the end of the study, eight patients dropped out. The final sample size resulted in 32 consecutive partially or fully edentulous patients (32 females; mean age 64.6 years) with 98 submerged implants. In only one patient, maxillary implant failed during healing period. No prosthesis failed during the entire follow-up, and no major complications were recorded. Implant and prostheses success resulted in an overall survival rate of 98, 98% and 100%, respectively. Three-year mean marginal bone loss was 1.35 ± 0.21 (CI 95% 1.24–1.38). Successful soft tissue parameters were found around all implants. Conclusions: Oral bisphosphonate therapy did not appear to significantly affect implant survival and success in case of accurate treatment time selection, minimally invasive surgical approach and constant follow-up. Further prospective studies involving larger sample sizes and longer durations of follow-up are required to confirm these results

Crestal sinus lift using an implant with an internal L-shaped channel : 1-year after loading results from a prospective cohort study

Purpose: To evaluate the clinical and radiographic outcomes of a one-stage crestal sinus elevation procedure using a self-tapping endosseous implant system (iRaise, Maxillent, Herzliya, Israel) developed for sinus augmentation, 1 year after loading. Materials and methods: Patients needing restoration in the posterior maxilla with a residual alveolar crest of 3 to 8 mm in height and 5 mm in width distal to the canine as measured on CBCT scan were treated using the iRaise sinus lift system. Outcome measures were: implant and prosthetic failures, any complications, increased bone height (iBH), marginal bone loss (MBL), implant stability quotient (ISQ), radiographic tissue remodelling patterns using the sinus grafting remodelling index (SGRI), volumetric measurements of sinus graft, patient self-reported post-surgical swelling, consumption of pain medication and histological analysis. Results: A total of 30 consecutive participants with a mean age of 54.2 ± 9.4 years underwent a transcrestal elevation of the sinus membrane, insertion of bone graft, and implant placement. A total of 50 implants were placed (30 iRaise system implants and 20 adjunctive iSure implants, Maxillent). The mean follow-up was 15.8 ± 2.1 months after implant loading. One patient dropped out at the 1-year after loading follow-up examination. No implants and no prostheses failed during the entire follow-up. One patient experienced a small membrane tear. Before implant insertion, the mean residual alveolar ridge height was 4.64 ± 0.86 mm (range: 3.4-6.4 mm; 95% CI: 4.39-5.01 mm). One year after loading, the bone height was 16.86 ± 3.13 mm (95% CI 15.83-18.07 mm). At the 1-year after loading follow-up, the mean MBL was 0.19 ± 1.05 mm (95% CI 0.02-0.78 mm). The mean ISQ at implant placement was 65.2 ± 5.4 (95% CI 63.6-67.4) and increased during the healing period reaching the mean value of 73.6 ± 3.7 (95% CI 73.1-75.9; range 62-79). The difference was statistically significant (8.4 ± 5.3; 95% CI 5.9-39.7; P = 0.0000). One year after loading, SGRI score was evaluated in 23 implants. Overall, the mean SGRI value was 2.29 ± 2.41 mm (95% CI 1.22-2.98 mm). Bone volume at implant placement was 2.41 ± 0.25 CC (95% CI 2.22-2.48 CC). During the 6-month, submerged healing period, a slight bone contraction of 11.3% were observed. (2.13 ± 0.24 CC;95% CI 2.02-2.26; difference = 0.27 ± 0.25 CC; 95% CI 0.10-0.36; P = 0.0011). At the first year post-loading period, the bone graft remained stable (2.11 ± 0.22 CC; 95% CI 2.02-2.24). The difference was not statistically significant (0.02 ± 0.07 CC; 95% CI 0.01-0.04; P = 0.2166). From the patient's point of view, the mean pain value was 0.52 ± 0.74 (range 0-3); mean swelling value was 0.27 ± 0.52 (range 0-2); and the mean consumption of analgesic was 0.87 ± 4.94 tablets (range 0-4) 3 days after surgery. Morphological and histomorphometric analyses showed that all the samples had a normal structure without inflammatory infiltrate, six months after healing. The following fractions (%) were found: bone (immature bone + mature bone): 44.07 ± 4.91; residual biomaterial: 23.98 ± 2.64; medullary spaces: 31.95 ± 3.16. Conclusions: Sinus floor augmentation can be successfully accomplished with a transcrestal approach using a dedicated implant system. A physiologic contraction of 11.3% of the original volume of the bone graft was experienced during the first 6 months of healing; afterwards, no additional graft volume reduction was observed. Long-term clinical studies are needed to confirm these preliminary results

Definitive Abutments Placed at Implant Insertion and Never Removed: Is It an Effective Approach? A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Purpose: To assess whether repeated abutment disconnections and reconnections have any impact on peri-implant bone resorption and soft tissue healing. Materials and Methods: Electronic and manual searches were conducted for English-language articles published up to March 2017 that identified a relation between repeated disconnections of implant abutments (PA group) and prosthetic or implant failures, complications, marginal bone loss (MBL), soft tissue healing, and esthetic evaluation (pink esthetic score [PES]) after at least 1 year of function compared with implants receiving a final abutment at the time of implant placement (DA group). Results: Fourteen articles (535 patients with 994 implants) were selected for qualitative analysis. Six of these were included in the meta-analysis. Five prostheses failed in the PA group and 1 failed in the DA group (P = .1047). Seven biologic complications occurred in the PA group and 6 occurred in the DA group (P = .8121). MBL was significantly less in the DA group (difference, 0.279 mm; P = .000). Greater buccal recession occurred in the PA group (difference, 0.198 mm; P = .0004). The PES evaluation showed no differences between groups (P = .289). Conclusions: Repeated abutment disconnections and reconnections considerably increased MBL and buccal recession. Further studies are needed to confirm these result

Immediate Loading of Fixed Complete Denture Prosthesis Supported by 4–8 Implants Placed Using Guided Surgery: A 5-Year Prospective Study on 66 Patients with 356 Implants

Background: High primary implant stability is considered one of the main factors necessary for achieving predictable treatment outcomes with immediately loaded implant-supported screw-retained fixed complete denture prosthesis (FCDP). Purpose: To evaluate the 5-year clinical and radiographic outcomes of immediately loaded implants placed in edentulous patients using computer-assisted template-guided surgery to support a FCDP. Materials &amp; Methods: Patients in need to be restored with a FCDP in the mandible or maxilla were included in this prospective study/ and treated using computer-assisted template-guided surgery. Implant sites were prepared in order to achieve an insertion torque ranging between 35–45 Ncm in the mandible and 45–55 Ncm in the maxilla. A prefabricated screw-retained provisional prosthesis was delivered the day of the surgery. Outcomes were: implant and prosthesis cumulative survival rate (CSR), any complications, and peri-implant marginal bone loss (MBL). Results: Sixty-six patients received 356 implants to support 68 FCDPs. Each patient received 4–8 implants. Seven implants failed in six patients, resulting in a CSR of 98.1%. Two definitive prostheses failed resulting in CSR of 97.1%. Mean MBL of 1.62 6 0.41 mm was reported at the 5-year follow-up. Five implants (1.4%) showed a mean mesio-distal peri-implant bone loss greater than 3.0 mm and received nonsurgical therapy. Conclusions: immediately loaded implants placed in edentulous patients using computer-assisted template-guided surgery to support a FCDP is a valid treatment concept in the medium term follow-up, for edentulous patient