***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: BACKGROUND The aim of the present prospect i ve longitudinal study of periodontally diseased and periodontally healthy patients was a clinical , microbiological , and radiographic comparison of teeth and implants and an assessment of the implant success rate . METHODS Thirty-nine partially edentulous patients provided with a total of 150 implants were enrolled in the study . Oral rehabilitation was undertaken in 15 patients treated for generalized aggressive periodontitis ( GAgP ) , 12 patients treated for generalized chronic periodontitis ( GCP ) , and 12 periodontally healthy patients . The examinations of the teeth and implants were carried out within the framework of a 3-month recall schedule over a 3-year period . At each session , clinical parameters for probing depth ( PD ) , gingival recession ( GR ) , attachment level ( AL ) , gingival index ( GI ) , and plaque index ( PI ) were recorded , and the composition of the subgingival microflora determined by dark-field microscopy . In the periodontally diseased patients , Actinobacillus actinomycetemcomitans ( A.a . ) , Porphyromonas gingivalis ( P.g . ) , and Prevotella intermedia ( P.i . ) were detected at teeth and implants by DNA analysis in the first and third years after insertion of the superstructure . Intraoral radiographs of the teeth and implants were taken at baseline , immediately after insertion of the superstructure , and then 1 and 3 years later . RESULTS The GI and PI at implants and teeth remained below 0.25 and 0.6 , respectively , in all patient groups throughout the study period . At the implants and teeth , a slight increase in PD and a continuous attachment loss was recorded in the GAgP patients . The attachment loss was greater at the implants than at the teeth in all groups . The morphological distribution of the microorganisms revealed virtually healthy conditions in all groups . A.a . was detected in two GAgP patients , whereas P.g . and P.i . were found more frequently both in the GAgP and in the GCP patients . Radiographically detected bone loss was higher after 3 years at implants and teeth in the GAgP patients than in the other two groups . The implant success rates recorded were 100 % in the periodontally healthy and GCP patients , and 95.7 % in the maxilla and 100 % in the m and ible of the GAgP patients . CONCLUSIONS The results show that oral rehabilitation can be performed with implants in patients treated for generalized aggressive and chronic periodontitis . However , slight attachment loss and bone loss were registered at the implants and teeth in the patients with aggressive periodontitis BACKGROUND Periodontitis and peri-implantitis are linked to the presence of several key pathogens . The treatment of these infectious processes therefore involves the reduction/eradication of bacteria associated with periodontitis . METHODS This prospect i ve , split-mouth , single-blind study followed the colonization of ' pristine ' sulci created in 42 partially edentulous patients during implant surgery ( e.g. abutment connection ) . The hypothesis was that the composition of the maturing subgingival plaque in these ' fresh ' peri-implant pockets would soon ( within 2 weeks ) be comparable to the subgingival microbiota of teeth with similar clinical parameters ( reference sites ) , including the presence of bacteria associated with periodontitis . Per patient , four subgingival plaque sample s were taken from shallow and medium pockets around implants ( test sites ) , and teeth within the same quadrant ( undisturbed microbiota as control sites ) , 1 , 2 , 4 , 13 , 26 and 78 weeks after abutment connection , respectively . The sample s were analysed by either checkerboard DNA-DNA hybridization , or cultural techniques , or real-time polymerase chain reaction ( PCR ) for intra-subject comparisons ( teeth vs. implant , for comparable probing depths ) . RESULTS Checkerboard DNA-DNA hybridization and real-time PCR revealed a complex microbiota ( including several pathogenic species ) in the peri-implant pockets within 2 weeks after abutment connection . After 7 days , the detection frequency for most species ( including the bacteria associated with periodontitis ) was already nearly identical in sample s from the fresh peri-implant pockets ( 5 % and 20 % of the microbiota belonging to red and orange complex , respectively ) when compared with sample s from the reference teeth . Afterwards ( e.g. between weeks 2 and 13 ) , the number of bacteria in peri-implant pockets only slightly increased ( + /-0.1 log value ) , with minor changes in the relative proportions of bacteria associated with periodontitis ( 8 % and 33 % of the microbiota belonging to red and orange complex , respectively ) . Although small differences were seen between teeth and implants at week 2 with cultural techniques , a striking similarity in subgingival microbiota was found with this technique from month 3 on , with nearly identical detection frequencies for bacteria associated with periodontitis for both abutment types . CONCLUSIONS This study indicates that the initial colonization of peri-implant pockets with bacteria associated with periodontitis occurs within 2 weeks OBJECTIVES To evaluate the long-term survival rates of dental implants  according to the patient 's periodontal status , as well as to estimate if the effect of periodontal status regarding implant failure is constant throughout the long-term follow-up . MATERIAL S AND METHODS This was a historical prospect i ve cohort study design of all consecutive patients operated from 1996 to 2006 at a periodontal clinic . The cohort consisted of 736 patients , with a total of 2336 dental implants .  An extended Cox proportional hazards model , which includes interaction terms between survival time and variables of interest , was used . RESULTS Patients ' mean ( SD ) age was 51.13 ( 12.35 ) . The follow-up time was up to 144 months , with a mean ( SD ) of 54.4 ( 35.6 ) months . The overall implant raw survival rate was 95.9 % . The Kaplan-Meier estimates for the cumulative survival rate ( CSR ) at 108 months were 0.96 and 0.95 for implants inserted into healthy and moderate chronic periodontal patients , respectively . The CSR declined to 0.88 at 108 months for the severe periodontitis group . The extended Cox model revealed that severe chronic status turned out to be a significant risk factor for implant failure after 50 months of follow-up [ hazard ratio (HR)=8.06 ; p<0.01 ] . The extended Cox model for smoking indicates a near-significant effect after 50 months ( HR=2.76 ; p=0.061 ) . CONCLUSIONS Periodontal status and smoking are significant risk factors for late implant failures . The HR for periodontal and smoking status are not constant throughout the follow-up period BACKGROUND The aim of this prospect i ve study is to evaluate the three-dimensional marginal bone level around implants 5 to 15 years after loading in partially edentulous patients treated for generalized chronic periodontitis ( GCP ) and generalized aggressive periodontitis ( GAgP ) . METHODS Seventeen patients with GCP and 17 patients with GAgP were treated with a total of 119 implants .  Patients were examined clinical ly on a 3-month recall schedule after insertion of the superstructure , and radiographs were taken at fixed intervals . At the end of the observation period , cone-beam computed tomography was used for the analysis of the circumferential three-dimensional bone level ( mesial , distal , buccal , and lingual/palatal ) and determination of keratinized mucosa thickness ( KMT ) . RESULTS In both groups , a significant bone loss at implants was observed buccally ( GAgP group : 4.49 ± 2.93 mm ; GCP group : 3.57 ± 2.94 mm ) with significantly more average bone loss in patients with GAgP ( 3.00 ± 1.67 mm ) compared to in patients with GCP ( 2.45 ± 1.08 mm ) . The lowest values for KMT in both groups were found in the anterior m and ible ( GAgP group : 0.99 ± 1.13 mm ; GCP group : 0.82 ± 0.91 mm ) . There were significant correlations between clinical parameters and bone loss in m and ibles of patients with GAgP. CONCLUSIONS The lowest value for KMT in both groups was found in the m and ible . Bone loss was observed buccally and was more pronounced in patients with GAgP , with a significant correlation with keratinized mucosa and increased inflammation BACKGROUND The aim of this prospect i ve 10-year study of partially edentulous subjects treated for generalized aggressive periodontitis and periodontally healthy subjects was a clinical , microbiologic , and radiographic comparison of teeth and implants and assessment of the implants ' success rate . METHODS Five subjects treated for generalized aggressive periodontitis ( GAgP ) and five periodontally healthy subjects who were orally rehabilitated with osseointegrated implants  participated in the study . First , they were examined 2 to 4 weeks before extraction of the non-retainable teeth ( baseline ) and 3 weeks after insertion of the final abutments . All further examinations were performed during a 3-month recall schedule over a 10-year period . At every session , clinical parameters were recorded , and the composition of the subgingival microflora was determined . Radiographs were taken at baseline after insertion of the superstructure and 1 , 3 , 5 , 8 , and 10 years later . RESULTS Throughout the follow-up period , the peri-implant gingival index of GAgP subjects was significantly higher than in periodontally healthy subjects . There was no difference in plaque index between teeth and implants or between the two groups . The peri-implant probing depths were comparable in the two groups and remained < or = 4 mm throughout the follow-up . The probing depth was significantly higher around the teeth of the GAgP subjects compared to periodontally healthy subjects . Implants of GAgP subjects showed a significantly higher attachment loss ( Ø 2.4 mm ) . The attachment level at teeth and implants of the periodontally healthy subjects and at teeth of the GAgP subjects was almost unchanged . Microbiologically , GAgP subjects had fewer cocci and more motile rods and filaments at teeth and implants than periodontally healthy subjects . GAgP subjects showed significantly more peri-implant bone loss in the first year ( Ø 2.07 mm ) and in the subsequent 9 years ( total 1.3 mm ) . Bone loss at teeth also was significantly higher at baseline ( Ø 26.39 % ) and in the following years ( total 9.3 % ) . Implant survival rates were 100 % in periodontally healthy subjects versus 83.33 % in GAgP subjects . CONCLUSIONS This 10-year study showed that partially edentulous subjects treated for GAgP can be rehabilitated successfully with osseointegrated implants . However , the bone and attachment loss at the implants were higher than in periodontally healthy subjects The aim of this study was to longitudinally follow up osseointegrated titanium implants in partially dentate patients by clinical , radiographic and microbiological parameters in order to evaluate possible changes in the peri-implant health over time . Fifteen individuals treated with titanium implants , ad modum Brånemark , and followed for ten years were included in the study . Before implant placement ten years previously , the individuals had been treated for advanced periodontal disease and thereafter been included in a maintenance care program . The survival rate of the implants after ten years was 94.7 % . The bone loss was 1.7 mm when using the abutment-fixture junction as a reference point . Of the individuals , 50 % were positive for plaque at the implants . Bleeding on sulcus probing was present at 61 % of the implant surfaces . Ten years previously , the individuals had been carriers of putative periodontal pathogens , such as Porphyromonas gingivalis , Prevotella intermedia , Actinobacillus actinomycetemcomitans , Capnocytophaga spp . and Campylobacter rectus , and were also carriers of these species at the current examination . The results of the present study suggest that the presence of these putative periodontal pathogens at implants may not be associated with an impaired implant treatment . These species are most likely part of the normal resident microbiota of most individuals and may therefore be found at r and om at both stable and progressing peri-implant sites BACKGROUND Comparatively few studies with at least 5 years of follow-up are available that describe the use of implants in prosthetic rehabilitation of partially edentulous patients . R and omized , controlled clinical studies that evaluated the effect of different surface design s of screw-shaped implants on the outcome of treatment are also sparse . OBJECTIVE To determine , in a prospect i ve r and omized , controlled clinical trial , the outcome of restorative therapy in periodontitis-susceptible patients who , following basic periodontal therapy , had been restored with implants with either a machined- or a rough-surface topography . MATERIAL AND METHODS Fifty-one subjects ( mean age , 59.5 years ) , 20 males and 31 females who , following treatment of moderate-to-advanced chronic periodontitis , required implant therapy for prosthetic rehabilitation were recruited . Seventeen of the patients were current smokers . Following the active treatment , all subjects were included in an individually design ed maintenance program . A total of 56 fixed partial dentures ( FPDs ) and a total of 149 screw-shaped , and self-tapping implants ( Astra Tech implants ) -- 83 in the maxilla and 66 in the m and ible -- were installed in a two-stage procedure . Each patient received a minimum of two implants and by r and omization every second implant that was 
    Output:
    
There is no difference , in terms of implant survival rate , between periodontitis and non-periodontitis patients .
However , patients with history of periodontitis had lower implant success rate ( more MBL and incidence of peri-implantitis ) when compared with non-periodontitis patients