***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 This r and omized clinical trial tested hypotheses that there are no differences in patient satisfaction , component costs , or treatment and maintenance times when m and ibular overdentures are retained by one or two implants . MATERIAL S AND METHODS Subjects wearing conventional complete dentures were r and omized to receive either one midline or two bilateral m and ibular implants followed by a m and ibular denture reline to incorporate implant retention . They indicated on a visual analog scale satisfaction with their dentures before implants and at 2 months and 1 year after implant retention . Satisfaction outcomes between the two groups were compared using the Wilcoxon/Mann-Whitney nonparametric rank test , while changes within each group were analyzed using signed-rank tests . Component costs and times for surgery , prosthodontic treatment , and maintenance were compared using nonparametric and t tests . RESULTS Eighty-six subjects enrolled in this study and 85 completed the 1-year follow-up , at which median satisfaction was 93 ( maximum 100 ) in the single-implant group and 94 in the two-implant group ( P > .5 ) . Within each group , median improvement in satisfaction was similarly dramatic ( approximately 44 ) and significant ( P < .001 ) . Prosthodontic maintenance time was similar for both groups ( P > .37 ) , but the single-implant group had significantly lower component costs ( P < .001 ) and lower times for surgery ( P = .002 ) , postsurgical denture maintenance ( P = .021 ) , and denture reline ( P < .001 ) . Five implants failed in four subjects , all in the two-implant group and all before denture reline . CONCLUSION Lower component costs and treatment times , with comparable satisfaction and maintenance time over the first year , indicate that a m and ibular overdenture retained by a single midline implant may be an alternative to the customary two-implant overdenture for maladaptive denture patients BACKGROUND The aim of the present study was to compare the peri-implant soft tissue health status of implants supporting overdentures with bar attachments or ball attachments in the m and ible , as well as patient satisfaction with these attachment types . METHODS The study included a Dolder bar group with 18 cases ( 43 implants ) and a ball attachment group with 18 cases ( 51 implants ) . The mean function period in the Dolder bar group was 49 months ( range : 12 to 72 months ) and in the ball attachment group , the mean was 23 months ( range : 12 to 40 months ) . Implants were clinical ly evaluated by using a modified plaque index ( mPI ) , modified sulcus bleeding index ( mSBI ) , and probing depths . Patient satisfaction with the treatment was recorded using a question naire . RESULTS mPI , probing depth , and mSBI did not statistically differ between groups ( Mann-Whitney U test , P > 0.05 ) . Patient satisfaction was similar with both retentive systems . CONCLUSION Within the limits of this study , we concluded that there was no significant difference between the 2 attachment types used for implant-supported overdentures with respect to the soft tissue health status or patient satisfaction OBJECTIVES Immediate loading of two unsplinted m and ibular implants by means of an overdenture may be a viable and cost-effective treatment option to improve the patient 's oral health-related quality of life . We therefore conducted a prospect i ve observational study to estimate implant survival and patient satisfaction after an immediate loading protocol in edentulous patients . MATERIAL S AND METHODS Twenty edentulous patients who received two interforaminal implants ( Straumann St and ard implant , length 12 mm ) were included in our study . Immediately after implant placement , ball attachments with a diameter of 2.25 mm were placed on the implants and the respective matrices were directly incorporated in the existing complete denture . Clinical recalls were scheduled 1 week , 1 , 3 , 6 months , and 1 and 2 years after implant placement . The following clinical parameters were assessed : gingival bleeding index ( GBI ) , visual plaque index ( VPI ) , and soft tissue overgrowth . In addition , we also assessed radiological bone level change ( RBLC ) using panoramic radiographs , and patient satisfaction using a visual analogue scale at baseline , after 6 months and 2 years . RESULTS No implant failures occurred during the 2-year observation period , result ing in a survival rate of 100 % . The mean RBLC was 0.67 mm ( 95 % Confidence Interval [ 95 % CI ] : 0.47 - 0.86 mm ) two years after surgery . The GBI and VPI after two years were 24 ( 95 % CI : 9 - 38)% and 36 ( 95 % CI : 19 - 53)% , respectively . Soft tissue overgrowth was 1.6 mm ( 95 % CI : 1.1 - 2.1 ) on average after two years . In a multivariate regression model , patients with a GBI ≥50 % on average showed an increased RBLC ( -0.6 mm , p = 0.007 ) . High patient ratings were recorded for overall satisfaction . Overall patient satisfaction measured on a scale between one and ten was 5.2 ( 95 % CI : 2.1 - 8.5 ) before implant placement and 9.5 ( 95 % CI : 9.1 - 10 ) after 2 years . CONCLUSION Immediate loading of two unsplinted interforaminal implants in overdenture patients using ball attachments is a clinical ly viable treatment option that leads to a high survival rate and oral health-related quality of life This study was design ed to compare the results of immediate and delayed loading of implants with implant-retained m and ibular overdentures . Ten patients ( test group ) received 40 Brånemark System MKII implants ( 4 per patient ) placed in the interforaminal area of the m and ible . St and ard abutments were immediately screwed to the implants , rigidly connected with a bar , and immediately loaded with an overdenture . Ten patients ( control group ) received the same type and number of implants in the same area , but the implants were left to heal submerged . Four to 8 months later , st and ard abutments were screwed to the implants and the same prosthetic procedure was applied . Each implant was evaluated at the time of prosthetic loading and at 6 , 12 , and 24 months after the initial prosthetic load with the following parameters : modified Plaque Index ( MPI ) , modified Bleeding Index ( MBI ) , probing depth ( PD ) , and Periotest . Peri-implant bone resorption was evaluated on panoramic radiographs taken 12 and 24 months after initial prosthetic loading . No significant differences were found between the 2 groups regarding MPI , MBI , Periotest , peri-implant bone resorption , and PD at 6 and 24 months ( P > .05 ) . The only difference was found regarding PD values on the mesial and lingual sites at 12 months ( P < .05 ) . The cumulative success rate of implants was 97.5 % in both groups . Results from this study showed that immediate loading of endosseous implants rigidly connected with a U-shaped bar does not seem to have any detrimental effect on osseointegration . Conversely , this method significantly shortens the duration of treatment with relevant satisfaction for the patients PURPOSE The purpose of the present study was to evaluate and compare treatment with m and ibular overdentures supported by one or two implants placed and loaded immediately . MATERIAL S AND METHODS Edentulous subjects with maxillary and m and ibular complete dentures were recruited to participate in the study . All subjects received new maxillary and m and ibular complete dentures , after which they were scheduled for implant surgery . Using a r and omized sampling system , one or two implants were placed in the interforaminal area , and separate ball attachments were connected to the implants . The existing m and ibular denture was relined , provided with retentive o-rings , and delivered the day of surgery . Subjects were seen for follow-up examinations after 3 , 6 , and 12 months , during which marginal bone levels and implant stability were measured . Survival rates were calculated and the data were analyzed statistically . RESULTS Thirty-six subjects ( 16 men and 20 women with a mean age of 53.2 years [ range , 38 to 69 years ] ) received 55 implants . Seventeen subjects received one implant in the symphyseal area , and the other 19 received two implants in the canine positions . Ten implants in nine subjects failed during the observation period , and three subjects with two implants each withdrew from the study , result ing in a 12-month implant survival rate of 81.8 % . Three subjects lost their only implant and one patient lost both implants . The remaining five subjects lost one of their two implants . Six of the failures occurred during the first month after placement . CONCLUSION Immediate loading of one or two separate implants by means of ball attachment-supported m and ibular overdentures should be performed with caution , as a higher than expected implant failure rate was observed . No statistically significant differences in failure rates between the two groups were observed Several surgical and prosthetic concepts for the treatment of patients with m and ibular atrophy and related lower denture problems are proposed and described in the literature . The present study discusses and evaluates the use of a new single-stage implant and overdenture with ball-attachment for this purpose . This study evaluates the clinical performance of the implants and abutments and addresses surgical and prosthetic complications that were encountered . Eighteen fully edentulous patients received two , single-stage Frialoc implants ( Friadent , Mannheim , Germany ) . The implants were left to osseointegrate for 3 months and were subsequently provided with ball-abutments and loaded through a m and ibular overdenture . After 1-year of clinical service , two implants were lost , which accumulated to a 1-year survival rate of 93.9 % ( SE 4.2 % ) . Patient satisfaction was high , and prosthetic complications and postinsertion maintenance were minimal . Three abutments loosened , one of which subsequently broke after 5 months of loading . Retightening of the attachment ( gold matrix ) was performed on seven occasions in four patients . Soft tissue response was excellent . Although minor hypertrophy of the peri-implant mucosa was observed , hardly any marginal bone loss between baseline and 1-year observations occurred . Short-term results indicate that m and ibular implant overdenture treatment by means of two ball-abutments , using Frialoc implants and prosthetic components , leads to good clinical results , both from an objective and a subjective perspective PURPOSE The aim of this study was to evaluate long-term marginal bone levels for two unsplinted implants supporting m and ibular overdentures using conventional and early loading protocol s with different implant surfaces and attachment systems . MATERIAL S AND METHODS A cohort of 106 edentulous participants ( mean age : 65 years ) was treated with m and ibular two-implant overdentures opposing complete maxillary dentures . Participants were r and omly allocated into three loading protocol groups using four implant systems ; single-stage surgery was performed for all participants , followed by an unsplinted prosthesis using six different attachment systems . St and ardized intraoral radiographs taken at baseline ( loading ) and over 10 years appraised marginal bone levels mesially and distally from reference points under magnification . Three calibrated examiners repeated measurements , diminishing intra- and interobserver variability . Progressive attrition of participants occurred as a result of deaths , dropouts , and emigration . Seventy-nine participants ( 74.5 % , mean age : 72 years ) were available at the 10-year recall . Differences in bone loss among different loading protocol s , implant surfaces , and attachment systems were tested using chi-square and one-way analysis of variance tests . RESULTS Minimal , time-dependent , long-term marginal bone loss occurred with all loading protocol s. Annual marginal bone loss progressed at low levels after the first year with episodes of bone loss and gain . There was stability in marginal bone levels over the long term , with the majority of remodeling occurring during the first year of function . Roughened implant surfaces may be beneficial during the early remodeling period . The amount of marginal bone loss in the first year of loading differed significantly by loading protocol and implant surface , whereas attachment system had a minor influence . Differences were not reflected in the success rates calculated using st and ard criteria . The remaining participants at 10 years were classified as successful related to the criterion of marginal bone loss , irrespective of the determining criteria for success . CONCLUSIONS Either a 2- , 6- , or 12-week loading protocol for m and ibular two-implant overdentures is possible in the long term , irrespective of the attachment system used . Minimal marginal bone loss may be attributed primarily to m and ibular basal bone remaining from long-term edentulism . Revision of the current implant success criteria to offer a stricter limit is desirable Purpose . To compare treatment outcome ( survival rate , condition of hard and soft peri-implant tissues ) and prosthodontic maintenance requirements of two versus three narrow-diameter bone level implants with Locator attachments supporting m and ibular overdentures . Material s and Methods . Twenty completely edentulous patients with atrophic m and ibles were treated . Ten patients ( Group A ) were treated with overdentures supported by two narrow ( 3.3-mm diameter ) implants ( Straumann AG , Basel , Switzerl and ) and ten patients ( Group B ) were treated with overdentures supported by three narrow implants . Locator ( Zest Anchors , USA ) attachments were used for prosthetic anchorage . St and ardized clinical and radiographic parameters ( survival rate , plaque index , calculus index , gingival index , bleeding index , probing depth and marginal bone loss ) were evaluated 
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Most investigators preferred verifying an initial high insertion torque ( ≥ 35 Ncm ) or ISQ value ( ≥ 60 ) before considering an implant for an immediate or early loading protocol .
Although all three loading protocol s provide high survival rates , early and conventional loading protocol s are still better documented than immediate loading and seem to result in fewer implant failures during the first year .
Only a few prospect i ve case series are available to document immediate loading of implants supporting an overdenture in the edentulous maxilla