***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE To investigate the effect of a 1-week postoperative course of 600 mg of ibuprofen taken four times a day on marginal bone level around oral implants . MATERIAL S AND METHODS Twenty-eight patients were allocated to the ibuprofen group ( 14 patients ) or no-ibuprofen group ( 14 patients ) . Overall , 57 implants were inserted , 31 implants in the ibuprofen group and 26 in the no-ibuprofen group . The primary outcome measure was the change in marginal bone level around oral implants from baseline ( 2 weeks postplacement ) to the 3- and 6-month radiographic examinations . The paralleling technique and a film holder coupled to a beam- aim ing device were used to take the periapical radiographs . Measurement of changes in bone level was made using a viewing box and ×8 magnifier . RESULTS Three subjects were withdrawn from the therapy early as they did not complete the dose of ibuprofen ( e.g. because of self-reported stomach upset ) . The mean marginal mesial bone loss from the baseline was 0.37 mm at the 3-month and 0.27 mm at the 6-month follow up for the ibuprofen group , while the corresponding values for the no-ibuprofen group were 0.15 mm and 0.08 mm . The mean marginal distal bone loss from the baseline was 0.42 mm at the 3-month and 0.2 mm at the 6-month follow up for the ibuprofen group , while the corresponding values for the no-ibuprofen group were 0.08 mm and 0.15 mm . There were no significant differences between the ibuprofen and no-ibuprofen groups when comparing the bone changes . CONCLUSION Administration of a short course of systemic ibuprofen for postoperative pain management following implant insertion may not have a significant effect on the marginal bone loss around oral implants in the early healing phase The results of a r and omised trial with bisphosphonate-coated dental implants  have been reported previously . Each patient received one coated and one uncoated implant in a double-blind split-mouth design study . After 6 months of osseointegration , resonance frequency analysis indicated better fixation of the coated implants . Reduced marginal bone resorption was also shown . However , it was not known whether the advantage of the bisphosphonate coating would persist over time . The radiographic results at 5 years after implant installation are reported herein . A blinded investigator measured marginal resorption on fresh radiographs obtained for 14 of the 16 patients ( two had died ) and compared these with the post-implantation images . Non-parametric statistics were used . All implants functioned well . The median marginal bone loss for control implants was found to be 0.70 mm , which is less than usually reported in the literature . The bisphosphonate-coated implants showed even less resorption ( median 0.20 mm ) . The median difference within each pair of implants after 5 years of use was 0.34 mm ( 95 % confidence interval 0.00 - 0.75 mm ; P=0.04 ) . The present data suggest that bisphosphonate-coated implants enable prolonged preservation of the marginal bone This study was design ed to radiographically evaluate the effect of surface macro- and microstructures within the coronal portion of the external hex implant at the marginal bone change after loading . The fifty-four patients included in the study were r and omly assigned to treatment groups with rough-surface implants ( TiUnite , n = 45 ) , a hybrid of smooth and rough surface implants ( Restore , n = 45 ) or rough-surface with microthreads implants ( Hexplant , n = 45 ) . Clinical and radiographic examinations were conducted at the time of implant loading ( baseline ) and at 1-year post-loading . A three-level mixed-effect ancova was used to test the significance of the mean marginal bone change of the three implant groups from baseline to 1-year follow-up . At 1-year , significant differences were noted in marginal bone loss recorded for the three groups ( P < 0.0001 ) . The rough surface with microthread implants had a mean crestal bone loss of 0.42 + /- 0.27 mm ; the rough surface implants , 0.81 + /- 0.27 mm ; and the hybrid surface implants , 0.89 + /- 0.41 mm . Within the limitations of this study , a rough surface with microthreads at the coronal part of implant maintained the marginal bone level against functional loading better than implants without these two features PURPOSE The purpose of this prospect i ve study was to assess the change of marginal bone level around three different types of external-hex implants  after 5 years using radiography . MATERIAL S AND METHODS Included in this study were 54 patients r and omly put into three different groups ;  rough-surface implants ( Brånemark ) , machined coronal aspect implants ( Restore ) , and microthreaded coronal aspect implants ( Hexplant ) .  Clinical and radiographic assessment s were performed contemporaneously with implant loading ( baseline ) and at 1 , 3 , and 5 years post-functional loading . A mixed-model analysis was employed to examine mean marginal bone change significance in the three treatment groups . RESULTS In a total of 31 out of 54 patients , 81 of 135 implants remained to the end of the study . At 5 years , the microthreaded coronal aspect implants had 0.61 ± 0.32 mm mean crestal bone loss ; the rough-surface implants without microthread , 0.99 ± 0.38 mm ; and the machined coronal aspect implants , 1.06 ± 0.39 mm . The rough-surface implants and the machined coronal aspect implants did not exhibit statistically significantly different marginal bone loss , whereas the microthreaded coronal aspect implants exhibited significantly less marginal bone loss ( P = .0015 ) . CONCLUSION In this research , rough-surface implants with microthreads showed positive long-term effects in preserving peri-implant bone level against functional loads when compared with implants lacking these aspects at the coronal part . Most of the bone loss was shown within 1 year of loading , and all types of implants stabilized after 1 year OBJECTIVES This r and omised , controlled multicentre trial aim ed at comparing two versions of a variable-thread dental implant design to a st and ard tapered dental implant design in cases of immediate functional loading for 36 months after loading . MATERIAL S AND METHODS 177 patients ( 325 implants ) were included at 12 study centres and r and omly allocated into one of three treatment groups : NAI ( variable-thread design , NobelActive internal connection ) , NAE ( variable-thread design , NobelActive external connection ) and , as control , NR ( st and ard tapered design , NobelReplace tapered groovy ) . Inclusion criteria concerned healed bony implant sites and feasibility for immediate loading . Clinical and radiographic examinations were performed at implant placement and after 3 , 6 , 12 , 24 and 36 months . The outcome measures were marginal bone remodelling ( primary outcome ) , implant survival and success , papilla score , plaque accumulation , and bleeding on probing . RESULTS 127 patients ( NAI : 45 , NAE : 41 , NR : 41 ) were followed-up and evaluated after 36 months . No significant differences in cumulative survival rates were seen for the groups ( NAI : 95.7 % ; NAE : 96.3 % ; NR : 96.6 % ) . In all groups , bone remodelling occurred during the first 3 months , with stable or even increasing bone levels after the initial remodelling period . The bone remodelling from insertion to 36 months for the NAI group ( -0.89 ± 1.65 mm ) was comparable ( P = 0.98 ) to that of the NR group ( -0.85 ± 1.32 mm ) . The NAE group showed comparable bone remodelling during the first year , with an increase in following years result ing in significantly less overall bone loss ( -0.16 ± 1.06 mm ) ( P = 0.041 ) . Overall improvement in papilla size was observed in all treatment groups . CONCLUSIONS Over 36 months , the results show stable or improving bone levels for all treatment groups after the initial bone remodelling seen during the first 3 months after placement . The variable- thread implants showed results comparable to those of st and ard tapered implants in cases of immediate function , and therefore can be considered as a treatment option for immediate loading PURPOSE The purpose of this clinical trial was to evaluate whether the crestal bone height around dental implants  could be influenced by the use of a platform-switching protocol . MATERIAL S AND METHODS All implants placed in the year 2006 in healed bone without any need for ridge augmentation were included in this study . The following groups were created : ( 1 ) wide-diameter implants were placed subcrestally and regular-diameter cover screws were connected ; ( 2 ) regular-diameter implants were placed at the crest and regular-diameter cover screws were connected . St and ardized radiographs were obtained after insertion of the definitive prosthesis and after 1 year . Calibrated measurements were conducted initiating from the mesial and distal bone peaks to the implant-abutment junction . The average value of the mean medial and mean distal values was calculated and analyzed with an unpaired two-tailed t test . P values < .05 were regarded as statistically significant . RESULTS In all , 89 dental implants in 36 patients were evaluated . The implants with a platform-switched configuration ( n = 75 ) exhibited statistically significantly less bone loss at time of insertion of the definitive prosthesis ( 0.30 + /- 0.07 mm versus 0.68 + /- 0.17 mm ; P < .05 ) and at 1 year ( 0.39 + /- 0.07 mm versus 1.00 + /- 0.22 mm , P < .01 ) when compared to the nonplatform-switched implants ( n = 14 ) . CONCLUSION Platform-switched implants seem to limit crestal bone remodeling 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 . MATERIAL S 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 assessment s 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 result ed 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 result ed 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 prospect i ve studies involving larger sample sizes and longer duration s of follow-up are required to confirm these results Abstract Objective Evaluation of differences in the clinical performance and crestal bone levels between implants restored with  single crowns with platform‐matched or platform‐switched abutments after 3 years . Material and Methods The study enrolled adult patients missing two or more adjacent teeth in the posterior m and ible with natural teeth mesial to the implant site . R and omization followed open‐flap implant insertion and the corresponding matching or switching healing abutments placed at surgery . Conventional loading was made with cemented crowns . Clinical follow‐up took place annually after loading up to 3 years . Bone level changes were measured in st and ardized radiographs as the variation in crestal bone from one evaluation to the next . Results Sixty‐three patients with a total of 135 implants ( 66 platform matching , 69 platform switching ) were analysed . From surgery to 36 months , mean bone loss was 0.28 ± 0.56 mm for the platform‐switching group and 0.68 ± 0.64 mm for the platform‐matching group . A statistically significant difference was found between groups ( p = 0.002 ) with an estimate of 0.39 mm ( 0.15–0.64 , 95 % CI ) in favour of platform switching . Conclusions After 3 years , platform‐switching restorations showed a significant effect in the preservation of marginal bone levels compared to platform‐matching restorations BACKGROUND It has been reported in many articles that marginal bone resorptions are prevented by platform-switch 
    Output:
    
MBL in all dental implants can be considered independent of the type of prosthetic rehabilitation and the moment of load ; this was emphasized .
The MBL is smaller in dental implants with rough surfaces , switch platforms and infracrestal localization , as they are of multifactorial origin .