***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: OBJECTIVES the aim of this r and omized-controlled clinical trial was to compare the objective and subjective esthetic outcomes of two types of  screwed-retained single-implant crowns .  MATERIAL S AND METHODS participants were r and omly assigned to the test ( all-ceramic ) and control [ porcelain-fused-to-ceramic ( PFM ) ] groups and were seen under investigation at baseline ( B ) , crown insertion ( CI ) , 1-year follow-up ( 1Y ) , and 2-year follow-up ( 2Y ) . Objective parameters were assessed by an intra-oral digital photograph ( 1:1 ratio ) , a study cast , a st and ardized radiograph , periodontal/peri-implant measurements , and question naires were obtained for the subjective parameters . In addition , pink esthetic score ( PES ) and white esthetic score ( WES ) were calculated for both groups . For the subjective evaluation , a visual analogue scale ( VAS ) question naire was used to assess the level of patient satisfaction regarding the esthetic outcome . Then , nine expert clinicians visually inspected and assessed subjective evaluation at the professional level . Statistical analysis was used to compare between groups and investigational appointments . RESULTS twenty patients were included in the study , 10 allocated to the all-ceramic group and 10 to the PFM group . No statistically significant differences were observed for the objective measurements comparing the test and control groups . Minor chipping of the ceramic veneering material was observed in the two patients of control group . The mean difference for all groups comparing objective parameters revealed an increase of papilla height between time points . A slight recession ( 0.26 mm ) of the peri-implant mucosal margin at the implant site was observed between 1Y and 2Y . Mean values for PES and WES were 13.9 and 13.1 for the PFM group and for the all-ceramic group , respectively . These values were not statistically significant . Implant crown volume , outline , translucency , and characterization showed major discrepancies with the contra-lateral natural teeth . As for subjective parameters , VAS patients ' responses regarding their perceptions of the esthetic outcome showed no statistical differences between groups and clinicians ' accuracy scores were 50 % and 47 % for PFM and all-ceramic crowns , respectively . CONCLUSION PFM and all-ceramic single-implant restorations may be indistinguishable from each other regarding the objective /subjective assessment of esthetic integration . The material chosen for fabricating an implant crown per se does not ensure an optimal esthetic outcome if other esthetic parameters are not present OBJECTIVES The aim of the present study was to evaluate the outcome of immediate functional loading of implants in single-tooth replacement using two different installation procedures . MATERIAL AND METHODS One hundred and fifty-one subjects , who required single-tooth rehabilitation in the area of 15 - 25 and 35 - 45 , were enrolled in eight private clinics in Italy . The implant sites were r and omly allocated to one of the following treatment groups . In the control group , in which a st and ard preparation procedure for implant placement and submerged healing of the implant was used , abutment connection and loading of the implants were performed 3 months after installation . In the test group 1 , a st and ard preparation procedure for the implant placement and immediate functional loading of implant was carried out . In the test 2 group , however , a modified implant installation procedure ( osteotome technique ) was used followed by immediate functional loading of the implant . Clinical and radiographic examinations were performed at 3 and 12 months of follow-up at all sites . RESULTS Three implants ( 5.5 % ) from the test 2 group ( osteotome preparation ) and one ( 2 % ) from the test 1 group ( conventional drill preparation ) failed to integrate and were removed one and three months after implant installation . The mean marginal bone loss assessed at 12 months was 0.31 mm ( test 1 ) , 0.25 mm ( test 2 ) and 0.38 mm ( control ) ( no statistically significant differences were found between the three treatment groups . ) CONCLUSION It is suggested that immediate functional loading of implants that are placed with a conventional installation technique and with sufficient primary stability may be considered as a valid treatment alternative in a single-tooth replacement AIM The purpose of this prospect i ve study was to evaluate radiographic , clinical and aesthetic outcomes and patient satisfaction of cases treated with  platform-switched single implant restorations in the aesthetic region of the maxilla . Furthermore , the influence of an augmentation procedure 3 months before implant placement and the type of restoration ( screw-retained vs. cement-retained ) was evaluated . MATERIAL AND METHODS Sixty patients with a missing anterior tooth in the maxilla were treated with a Straumann Bone Level Implant . Bone augmentation was performed in 29 patients at 3 months before implant placement . Implants were loaded after 3 months of submerged healing . Follow-up was conducted at 7 and 18 months after implant placement . Peri-implant mucosa and implant crown aesthetic outcomes were determined using the Implant Crown Aesthetic Index ( ICAI ) and the Pink Esthetic Score-White Esthetic Score ( PES-WES ) . RESULTS No implants were lost . At 18 months after implant placement , mean bone level change was -0.10 ± 0.27 mm and mean probing pocket depth was 2.57 mm . No differences were found between augmented and nonaugmented sites ( P = 0.28 ) . The ICAI indicated satisfactory mucosa and crown aesthetics in 67 % and 75 % of the cases , respectively , while the PES score was 14.4 . ICAI mucosa ( P = 0.004 ) and PES ( P = 0.02 ) scores were significantly less favourable for augmented sites compared with nonaugmented sites . Patient satisfaction was high ( 8.9 ± 1.1 on VAS-score ) . CONCLUSIONS From the present prospect i ve , clinical study , it can be concluded that the Straumann Bone Level Implant shows an excellent survival rate , marginal bone stability and good clinical and aesthetic results . Bone augmentation before implant placement does not lead to more marginal bone loss . However , less favourable pink aesthetic outcomes were found in augmented sites compared with nonaugmented sites , while no differences were found between cement-retained and screw-retained restorations BACKGROUND The concept of early implant placement is a treatment option in post extraction sites of single teeth in the anterior maxilla .  Implant placement is performed after a soft tissue healing period of 4 to 8 weeks . Implant placement in a correct three-dimensional position is combined with a simultaneous guided bone regeneration procedure to rebuild esthetic facial hard and soft tissue contours . METHODS In this retrospective , cross-sectional study , 45 patients with an implant-borne single crown in function for 2 to 4 years were recalled for examination .  Clinical and radiologic parameters , routinely used in implant studies , were assessed . RESULTS All 45 implants were clinical ly successful according to strict success criteria . The implants demonstrated ankylotic stability without signs of a peri-implant infection . The peri-implant soft tissues were clinical ly healthy as indicated by low mean plaque ( 0.42 ) and sulcus bleeding index ( 0.51 ) values . None of the implants revealed a mucosal recession on the facial aspect as confirmed by a clearly submucosal position of all implant shoulders . The mean distance from the mucosal margin to the implant shoulder was -1.93 mm on the facial aspect . The periapical radiographs showed stable peri-implant bone levels , with a mean distance between the implant shoulder and the first bone-implant contact of 2.18 mm . CONCLUSIONS This retrospective study demonstrated successful treatment outcomes for all 45 implants examined . The mid-term follow-up of 2 to 4 years also showed that the risk for mucosal recession was low with this treatment concept . Prospect i ve clinical studies are required to confirm these encouraging results PURPOSE The possibility of expediting dental implant therapy by early or immediate loading protocol s requires long-term clinical investigation . The aim of this prospect i ve cohort trial was to determine the 3-year implant success rate and prosthesis complications associated with functional loading 3 weeks after 1-stage placement of Astra Tech single-tooth implants replacing maxillary anterior teeth . A secondary objective was to determine peri-implant tissue responses at these implants . MATERIAL S AND METHODS The peri-implant bone and mucosal conditions of 43 implants in 39 subjects were radiographically and clinical ly measured 3 years after implant placement . RESULTS Of the 48 patients originally treated , 39 patients and 43 implants were examined at the 3-year time point . Three of 54 implants failed within the first year . No additional failures were recorded since the 12-month reporting period . Peri-implant bone levels were stable for the 3-year period following implant placement . The change in marginal bone levels after 3 years was 0.42 + /- 0.59 mm . Papilla growth was measured at 1 and 3 years ( 0.61 + /- 0.95 mm and 0.74 + /- 0.79 mm , respectively ) . The buccal peri-implant tissue dimensions at the gingival zenith also increased at 1 and 3 years ( 0.34 + /- 0.94 mm and 0.51 + /- 1.42 mm , respectively ) . No abutment screw loosening or fracture occurred . DISCUSSION AND CONCLUSIONS Early loading of endosseous dental implants placed in healed ridges offers select benefits to clinicians and their patients AIM this study compared the outcome of immediate non-occlusal loading with conventional loading for single implants in the maxillary aesthetic zone . It was hypothesized that immediate non-occlusal loading is not inferior to conventional loading . MATERIAL S AND METHODS sixty-two patients with a missing maxillary anterior tooth were r and omly assigned to be treated with an implant that was either restored with a non-occluding temporary crown within 24 h after implant placement ( the " immediate group " ) or was restored according to a two-stage procedure after 3 months ( the " conventional group " ) . All implants were installed in healed sites . Follow-up visits were conducted after 6 and 18 months post-implant placement . Outcome measures were radiographic marginal bone-level changes , survival , soft tissue aspects ( probing depth , plaque , bleeding , soft tissue level ) , aesthetics and patient satisfaction . RESULTS no significant differences were found between both study groups regarding marginal bone loss ( immediate group 0.91 ± 0.61 mm , conventional group 0.90 ± 0.57 mm ) , survival ( immediate group 96.8 % : one implant lost , conventional group 100 % ) , soft tissue aspects , aesthetic outcome and patient satisfaction . CONCLUSION within the limitations of this study ( sample size , follow-up duration ) , it was demonstrated that , for single implants in the anterior maxilla , the outcome of immediate non-occlusal loading was not less favourable than conventional loading OBJECTIVES The aim of this prospect i ve study was to evaluate dimensional alterations of the peri-implant tissues at  single-tooth restorations  from the time of implant placement to 1-year post-loading . MATERIAL AND METHODS Eleven patients , aged 18 - 36 years , subjected to single-tooth replacements with implant-supported restorations ( Brånemark implant system ) in the maxillary anterior region were included in the analysis . The implant installation was performed as a two-stage procedure with a 6-month healing interval . Bone dimensions were determined by direct assessment s immediately following implant placement and at abutment connection . The prosthetic restoration was placed approximately 1 month after abutment surgery . Radiographic and clinical examinations were performed at crown placement and at 1-year post-loading . Assessment s of the soft tissues at the implant site and at the neighboring teeth were performed before and during implant placement , before abutment connection , after crown placement and at the 1-year follow-up examination . Mean values and st and ard deviations were calculated for each variable and interval , with the subject as the statistical unit . RESULTS At the time of abutment connection , a mean loss of bone height at the facial and lingual aspect of the implant amounting to 0.7 - 1.3 mm ( P < 0.05 ) was recorded , whereas no significant change was noted at proximal sites . A mean reduction of 0.4 mm of the labial bone thickness was observed between implant placement and the second-stage surgery . The radiographic bone-to-implant level showed a mean loss of 0.9 mm between abutment connection and crown placement ( P<0.05 ) and a further 0.7 mm loss at 1 year ( P < 0.05 ) . The thickness of the labial mucosa was increased at crown placement followed by a slight remission at 1 year . During the corresponding interval , a mean apical displacement of the labial soft tissue margin of 0.6 mm had taken place ( P < 0.05 ) . A papilla fill of > or = 50 % was observed at a frequency of 32 % at crown placement and 86 % at 1 year . CONCLUSIONS The results demonstrated that following implant surgery remodeling takes place , which is manifested in diminished bone dimensions , both horizontally and vertically , at the facial aspect of the implant . The observed soft tissue alterations after the crown placement may affect the esthetic appeal of the restorative therapy BACKGROUND Early implant placement is one of the treatment options after tooth extraction .  Implant surgery is performed after a healing period of 
    Output:
    
It was consistently reported that facial malpositioning of implants increases the likelihood of mucosal recession .
It is not possible to identify any significant variation in esthetic outcomes based on the character of the abutment platform from the current literature .
Based on the findings , no significant difference can be established between all-ceramic and metal-ceramic prostheses with regard to esthetic indices over short observation periods .
No firm conclusions relating esthetic benefits for cement in comparison to screw retention can be identified .