***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: AIM To compare the immediate restoration of single implants in the esthetic zones performed on implants placed immediately after tooth extraction or 8 weeks later ( immediate replacement vs. immediate restoration ) . METHODS Sixteen patients ( 10 women and 6 men ) with a mean age of 35 years ( ranging from 21 to 49 years old ) were treated from 2004 to 2005 for single-tooth replacement in the upper arch . The patients were r and omly divided into two groups : in the test group patients received implants placed and restored ( non-occlusal loading ) at the time of tooth extraction ; in the control group implants were placed 8 weeks after tooth extraction and immediately restored .  All the patients received tapered effect ( TE ) implants from the Straumann Dental Implant System . The following parameters were evaluated at the moment of provisional restoration ( within 48 h after implant placement ) and at the 2 years follow-up visit : marginal bone resorption , papilla index , position of the mucosal margin . The implant stability quotient was measured at the moment of implant placement and at the moment of the delivery of the definitive restoration . RESULTS No statistically significant differences were found in any of the studied parameters between the test and the control groups ( P>0.05 ) . The implant stability quotient values between the test and control groups were significant ( P<0.05 ) at the moment of implant placement but were no more significant at the loading of the definitive restoration ( P>0.05 ) . CONCLUSION The results of the present study suggest that immediate replacement without functional loading may be considered a valuable therapeutic option for selected cases of single-tooth replacement in the esthetic area when TE implants are used . Implant stability at the moment of implant placement is slightly inferior in the immediate replacement group , but it does not affect the treatment result 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 The aim of this study was to report a clinical comparative assessment of crestal bone level change around single implants in fresh extraction sockets in the esthetic zone of the maxilla either immediately loaded or loaded after a delay . MATERIAL S AND METHODS Forty patients were included in a prospect i ve , r and omized study . All patients required 1 tooth extraction ( ie , 1 tooth with a hopeless prognosis ) and were r and omized into either the test group or the control group . Implants were positioned immediately after tooth extraction and were loaded immediately in the test group ( 20 implants ) and after 3 months in the control group ( 20 implants ) . The implant site was prepared , with at least 4 mm of sound apical bone below the implant apex , and the coronal margin of the implant was placed at the buccal level of the bone crest . All implants were 13 mm long ; 30 implants had a diameter of 5 mm , and 10 had a diameter of 3.75 mm . Radiographic examinations were made at baseline , at 6 months , and at 24 months . To compare the mean values between test and control group , a paired t test was performed ( considered statistically significant at P < .05 ) . RESULTS After a 24-month follow-up period , a cumulative survival rate of 100 % was reported for all implants . The control group result ed in a mean mesial bone loss of 1.16 + /- 0.32 mm and a mean distal bone loss of 1.17 + /- 0.41 ( mean bone loss , 1.16 + /- 0.51 mm ) . The test group result ed in a mesial bone loss of 0.93 + /- 0.51 mm and a distal bone loss of 1.1 + /- 0.27 mm ( mean bone loss , 1.02 + /- 0.53 mm ) . No statistically significant difference between control and test groups ( P > .05 ) was found . CONCLUSION The success rate and radiographic results of immediate restorations of dental implants placed in fresh extraction sockets were comparable to those obtained in delayed loading group BACKGROUND Single-rooted teeth deemed not restorable via conventional means may be c and i date s for implant placement at the time of tooth extraction .  Immediate implant placements are believed to preserve soft and hard tissue form and contours , reduce the need for augmentation procedures , minimize surgical exposure of the patient , reduce treatment time and improve esthetic outcomes . METHOD This retrospective review analyzed the  esthetic outcomes of 42 non-adjacent single-unit implant restorations completed using an immediate implant surgical placement protocol .  RESULTS The mean time in function was 18.9 months ( range 6 - 50 months ) and the majority of implants placed had a restorative platform diameter of 4.1 and 4.8 mm . A highly significant change in crown height due to marginal tissue recession of 0.9 + /- 0.78 mm ( P=0.000 ) was recorded for all sites , with no difference seen between implant systems ( P=0.837 ) . Thin tissue biotype showed slightly greater recession than thick tissue biotype ( 1 + /- 0.9 vs. 0.7 + /- 0.57 mm , respectively ) ; however , this difference was not statistically significant ( P=0.187 ) . Implants with a buccal shoulder position showed three times more recession than implants with a lingual shoulder position ( 1.8 + /- 0.83 vs. 0.6 + /- 0.55 mm , respectively ) with the difference being highly statistically significant ( P=0.000 ) . CONCLUSIONS Immediate implant placement requires very careful case selection and high surgical skill levels if esthetic outcomes are to be achieved . Long-term prospect i ve studies on tissue stability and esthetic outcomes are needed PURPOSE The aim of this study was to evaluate the feasibility of using a 2-stage implant system in a single-stage procedure and to study the impact of the microgap between the implant and the abutment . MATERIAL S AND METHODS Sixty edentulous patients ( Cawood class V or VI ) participated in this study . After r and omization , 20 patients received 2 IMZ implants placed in a single-stage procedure , 20 patients received 2 IMZ implants placed in the traditional 2-stage procedure , and 20 patients were treated with 2 ITI implants ( single-stage procedure ) . The implants were placed in the canine area of the m and ible . After 3 months , m and ibular overdentures were fabricated , supported by a bar- and -clip attachment . A st and ardized clinical and radiographic evaluation was performed immediately after prosthesis placement and after 12 and 24 months . RESULTS One IMZ implant of the 1-stage group and 1 IMZ implant of the 2-stage group were lost after 6 and 12 months , respectively . Apart from several significant but clinical ly irrelevant differences , the 3 groups did not appear to differ markedly with regard to clinical parameters during the evaluation period . The mean bone loss within the first 2 years of functioning ( 1.1 mm IMZ 1-stage , 0.8 mm IMZ 2-stage , 1.2 mm ITI ) was comparable for the 3 groups . DISCUSSION AND CONCLUSIONS The results of this study suggest that dental implants design ed for a submerged implantation procedure can also be used in a single-stage procedure and may be as predictable as when the same implants used in a 2-stage procedure or as 1-stage implants . Placement of the microgap at the crestal level in 2-stage implants did not appear to have an adverse effect on the amount of peri-implant bone loss at 2 years in this study population AIM The aim of this study was to compare the clinical outcome of submerged vs. non-submerged tapered implants placed into fresh extraction sockets . MATERIAL S AND METHODS A prospect i ve , controlled , multicenter , r and omized , clinical trial has been performed in two centers in Rome and Torino ( Italy ) . Thirty healthy patients were recruited according to the following inclusion criteria : need for an immediate post extraction implant , ages between 18 and 70 , horizontal defect depth < 2 mm , smokers < 10 cigarettes/day and absence of any circumstance or condition that could represent contraindications to implant surgery . The patients were r and omly allocated to submerged or non-submerged treatment groups immediately after flap elevation and tooth extraction . Submerged implants were exposed 8 weeks after the first surgery ; all implants were loaded with provisional restorations 12 weeks after the first surgery and with definitive restoration 12 weeks thereafter . Clinical and radiographic parameters were evaluated at baseline , at implant loading and at the 1-year follow-up visit . RESULTS The results showed statistically significant differences between the two groups in the mean value of keratinized tissue ( KT ) height after surgery that was significantly reduced for submerged implants when compared with transmucosal implants ( mean reduction of KT at year follow-up : T group 0.2 mm , S group 1.3 mm ; P=0.007 ) . CONCLUSION Similar outcomes were found for submerged and non-submerged implants placed in fresh extraction sockets with a horizontal peri-implant defect smaller than 2 mm , except for a reduction of KT in the submerged group . Either with a submerged or a non-submerged procedure , 1 mm of mean soft tissue recession is seen after 1 year when compared with the pre- extraction situation BACKGROUND Early implantation may preserve the alveolar anatomy , and the placement of a fixture in a fresh extraction socket helps to maintain the bony crest . Although a number of clinical studies exist , no histological reports show the outcome of implantation in fresh extraction sockets without the use of membranes in humans compared to implants placed in mature bone . METHODS Forty-eight healthy patients , receiving at least 4 fixtures in each of 2 symmetrical quadrants , underwent placement of 1 experimental fixture placed in a fresh extraction socket ( TI ) and 1 contralateral fixture in mature bone ( CI ) . TI were placed after atraumatical tooth extraction , with a surgical site at the apex of the socket and a tight contact between the fixture and the socket 's walls , but without the use of filling material s or membranes . The flap was coronally repositioned to obtain primary wound closure . Immediately after surgical intervention , a st and ardized periapical radiograph was taken . Second-stage surgery was done after 6 months . Six months after the second surgery , a second st and ardized periapical radiograph was taken and clinical parameters ( bleeding and plaque index ) recorded . Marginal bone loss ( MBL ) from the time of implant placement to the time of fixture removal was calculated by comparing periapical radiographs . TI and CI were then removed by a hollow drill to obtain histological specimens . Non-demineralized sections were stained by acid fuchsin and toluidine blue , and by von Kossa to evaluate the degree of bone mineralization . The percentage of direct implant-bone contact ( DBC ) was calculated by a computerized microscopic digitizer . RESULTS No significant differences in the clinical and radiographic parameters were observed between the 2 experimental categories . There was no statistically significant difference between TI and CI for DBC either in the maxilla or in the m and ible . No connective or fibrous tissues were present around TI or CI . Bone resorption was not present in any of the histological sections . CONCLUSIONS The present study shows that when a screw-type dental implant is placed without the use of barrier membranes or other regenerative material s into a fresh extraction socket with a bone-to-implant gap of 2 mm or less , the clinical outcome and degree of osteointegration does not differ from implants placed in healed , mature bone OBJECTIVE To determine clinical success when implants are placed in chronic periapical infected sites . STUDY DESIGN Fifty patients ( 25 females , 25 males , mean age 39.7 + /- 14.5 years ) were included in this prospect i ve controlled study . After r and omization , 25 Frialit-2 Synchro implants were immediately placed ( IP ) after extraction , and 25 Frialit-2 Synchro implants were placed after a 3-month healing period ( DP ) . Thirty-two implants were placed in the anterior maxilla and 18 implants were placed in the premolar region . Implant survival , mean Implant Stability Quotient ( ISQ ) values , gingival aesthetics , radiographic bone loss , and microbiologic characteristics of periapical lesions were evaluated for both groups . RESULTS Overall , 2 implants belonging to the IP group were lost , result ing in a survival rate of 92 % for IP implants versus 100 % for DP implants . Mean ISQ , gingival aesthetics and radiographic bone resorption , and periapical cultures were not significantly different with the IP and DP implants . CONCLUSIONS Immediate implant placement in chronic periapical lesions may be indicated BACKGROUND Dental implants have been used to replace missing teeth to provide function and esthetics . One goal of such restorations is to maintain host tissue around the implants . The purpose of this prospect i ve multicenter human clinical trial was to evaluate radiographic marginal bone levels around non-submerged hollow cylindrical and solid-screw implants for 5 years after loading . METHODS Patients older than 18 years of age with sufficient native bone to surround a dental implant without imposing on a vital structure were recruited at five sites .  Solid-screw or hollow-cylinder implants with a 
    Output:
    
Meta-analyses showed less CBL loss around IIP compared with implant placement in healed bone .
Platform-switched implants showed greater crestal bone preservation than non-platform-switched implants .
There was no significant difference in CBL with one- versus two-stage placement or use of immediate versus delayed IIP loading .
Although there were statistically significant differences favoring IIP , the small differences may not be clinical ly relevant .