***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: PURPOSE The aim of this study was to compare clinical outcomes and stability following immediate loading of two types of  tapered implants in the partially edentulous posterior maxilla and m and ible . MATERIAL S AND METHODS A r and omized controlled trial with 1 year of follow-up was performed on participants missing two consecutive teeth in a posterior quadrant with tapered implants with a hybrid textured surface . Group 1 received Osstem TSIII HA implants , and group 2 received Zimmer TSV implants . Group 1 implants were 4.5 or 5.0 mm in diameter , and group 2 implants were 4.7 mm in diameter ; all implants were 10 mm long . Subjects received provisional restorations within 48 hours . Definitive restorations were provided 3 months ( m and ible ) or 6 months ( maxilla ) later . Outcome measures were survival and success rates , marginal bone level change , implant stability quotient , and peri-implant soft tissue indices . RESULTS Fifty participants completed the trial ( group 1 : 52 implants in 26 patients ; group 2 : 48 implants in 24 patients ) . The success rates were similar--98.1 % in group 1 and 97.9 % in group 2 - -at 12 months after immediate loading , but marginal bone loss was significantly different according to the implant design . Implant stability increased significantly in both arches . There were no significant differences in soft tissue indices between implant systems . CONCLUSION If high primary stability is acquired , tapered implants with hybrid textured surfaces are predictable for immediate loading in the posterior maxilla and m and ible . In spite of the influence of implant design on marginal bone loss , all tapered implants showed successful clinical outcomes and stability in immediate loading 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 PURPOSE To evaluate the influence of macro- and microstructure of the implant surface at the marginal bone level after functional loading . MATERIAL S AND METHODS Sixty-eight patients were r and omly assigned to 1 of 3 groups . The first group received 35 implants with a machined neck ( Ankylos ) ; the second group , 34 implants with a rough-surfaced neck ( Stage 1 ) ; and the third , 38 implants with a rough-surfaced neck with microthreads ( Oneplant ) . Clinical and radiographic examinations were conducted at baseline ( implant loading ) and 3 , 6 , and 12 months postloading . Two-way repeated analysis of variance ( ANOVA ) was used to test the significance of marginal bone change of each tested group at baseline , 3 , 6 , and 12 month follow-ups and 1-way ANOVA was also used to compare the bone loss of each time interval within the same implant group ( P < .05 ) . RESULTS At 12 months , significant differences were noted in the amount of alveolar bone loss recorded for the 3 groups ( P < .05 ) . The group with the rough-surfaced microthreaded neck had a mean crestal bone loss of 0.18 + /- 0.16 mm ; the group with the rough-surfaced neck , 0.76 + /- 0.21 mm ; and the group with the machined neck , 1.32 + /- 0.27 mm . In the rough-surfaced group and the rough-surfaced microthreaded group , no statistically significant changes were observed after 3 months , whereas the machined-surface group showed significant bone loss for every interval ( P < .05 ) . DISCUSSION To minimize marginal bone loss , in addition to the use of a rough surface at the marginal bone level , a macroscopic modification such as the addition of microthreads could be recommended . A rough surface and microthreads at the implant neck not only reduce crestal bone loss but also help with early biomechanical adaptation against loading in comparison to the machined neck design . CONCLUSION A rough surface with microthreads at the implant neck was the most effective design to maintain the marginal bone level against functional loading 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 Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more PURPOSE To present long-term clinical and radiographic data on single-implant treatment in the anterior maxilla and to compare these results with comparable data of central implants supporting fixed prostheses in the edentulous maxilla . MATERIAL S AND METHODS A total of 38 patients consecutively restored with 47 single-implant crowns in the anterior maxilla were included in the single-implant ( study ) group . The implants in the edentulous group ( control ) were included by r and omly selecting one of the central implants ( closest to midline ) from 76 consecutively treated edentulous patients . Mean age was 25.4 years ( SD : 10.0 ) and 60.1 years ( SD : 11.6 ) at inclusion ( P < .001 ) for the study and control groups , respectively . Clinical and radiographic data were retrospectively retrieved from files holding up to 15 years of function in both groups . RESULTS No implants in the study group were lost ( cumulative success rate : 100 % ) , while 3 implants in the control group were lost ( cumulative success rate : 95.4 % ) . Ten single crowns were replaced ( 15-year cumulative survival rate : 77.0 % ) , and the study group showed more mucosal problems and fistulas compared to the implants in the control group ( P < .05 ) . Loose screws were a common problem in the single-implant group during the first 5 years of function , but bone loss did not differ significantly between patients with stable and loose screws/fistulas ( P > .05 ) or between study and control implants after 15 years ( P > .05 ) . CONCLUSIONS There is an obvious difference between the survival of the implants ( 100 % ) and original implant crowns ( 77 % ) in the study group . The present early single-implant restorations showed significantly more mechanical/fistula problems compared to central implants in the edentulous maxilla ( P < .05 ) , but bone response was similar for both groups during 15 years of follow-up . Bone loss was not affected by the level of the implant head in relation to the cementoenamel junction of adjacent teeth , nor was it affected by mechanical or mucosal problems or persistent fistulas of the single implants during the entire follow-up period BACKGROUND Numerous new implant design s and material s have become available over the last decade , each with special cl aims of superiority in restoring complex cases . Differences in existing clinical data bases , study design s , and methods of determining failures/survival are seldom st and ardized , which complicates comparisons of clinical performance of these new design s. Little information is available concerning the changes in stability of various design s and material s following clinical loading . METHODS A total of 30 VA medical centers and 2 dental schools combined to form the Dental Implant Clinical Research Group ( DICRG ) . More than 2,900 implants were placed , restored and data gathered from the time of placement to 36 months . Implant stability from uncovering to 36 months and survival from placement to 36 months were determined . Survival was determined using two different approaches -- considering all implants removed at any time , regardless of the reason ( DICRG approach ) , and considering only those that were removed following loading of the prosthesis ( post-loading approach ) . Survival was also determined for each of the three phases of implant treatment -- phase 1 , from the time of placement to uncovering and abutment connection ; phase 2 , from uncovering to placement and loading of the prosthesis ; and phase 3 , from loading of the prosthesis to 36 months . RESULTS The two approaches to determining survival for each implant design and /or material included in the study showed differences in reported numbers ranging from 1.1 % to 21.7 % . The largest difference in survival was for the commercially pure titanium screw ( used in this study only in the maxillary completely edentulous applications ) , which showed a 21.7 % greater survival rate . With the DICRG approach , the hydroxyapatite (HA)-cylinder had the highest survival ( 97.5 % ) . When considering the post-loading approach , the titanium-alloy screw had the highest survival ( 99.4 % ) , with the HA-cylinder having the next highest survival ( 98.6 % ) . The HA-cylinder did not show increased stability from uncovering to 36 months , and the HA-grooved implant became less stable . CONCLUSIONS HA-coated implants demonstrated the highest survival rate ; 2 ) the post-loading analysis approach inflated survival ; 3 ) non-HA implants showed increased stability following loading ; 4 ) HA-coated implants showed a slight decrease or no change in stability ; and 5 ) the clinical significance of the changes in implant stability must be determined for the long-term Purpose : This study was design ed to compare radiographically the effect of microthread on the coronal portion of the fixture on marginal bone level ( MBL ) around immediately placed dental implants in human subjects . Material and Methods : Forty-one roughened surface screw type Dentium oral implants ( Dentium ) were inserted in fresh extraction sockets of the anterior segment of maxilla of 30 patients . The implants were selected r and omly using either microthread design on coronal portion of the fixture ( Implantium ) ( test group ) or without microthread thread design ( Superline ) ( control group ) . MBL was measured using digital subtraction radiography technique after 3 , 6 , and 12 months . Results : At month 3 , the microthread groups have been associated with more marginal bone loss than the control group ( P = 0.04 ) . At months 6 and 12 , both groups had compar 
    Output:
    
A similar behavior of marginal bone loss between tapered and cylindrical geometries was observed ; however , implants that had micro-threads in the neck presented a slight decrease of marginal bone loss compared to implants with straight or smooth neck .
Success and survival rates were high , with cylindrical implants presenting higher success and survival rates than tapered ones .