Surgical crown lengthening: evaluation of the biological width. Placement of the preparation line and periodontal health--a prospective 2-year clinical study. Biological width formation to immediate implants placed at different level in relation to the crestal bone: an experimental study in dogs. Culture of human gingival fibroblasts on a biodegradable scaffold and evaluation of its effect on attached gingiva: a randomized, controlled pilot study. Analysis of the socket bone wall dimensions in the upper maxilla in relation to immediate implant placement. Clinical evaluation of a new collagen matrix (Mucograft prototype) to enhance the width of keratinized tissue in patients with fixed prosthetic restorations: a randomized prospective clinical trial. Dental implants for immediate fixed restoration of partially edentulous patients: a 1-year prospective pilot clinical trial in periodontally susceptible patients. Impact of implant diameter on bone level changes around platform switched implants: preliminary results of 18 months follow-up a prospective randomized match-paired controlled trial. A prognostic model for assessment of the outcome of endodontic treatment: Effect of biologic and diagnostic variables. Platelet-rich plasma-assisted guided bone regeneration for ridge augmentation: a randomized, controlled clinical trial. Arthroscopic Single-Row versus Double-Row Suture Anchor Rotator Cuff Repair Alveolar ridge reconstruction and/or preservation using root form bioglass cones. Ridge preservation with freeze-dried bone allograft and a collagen membrane compared to extraction alone for implant site development: a clinical and histologic study in humans. Buccal bone formation after flapless extraction: a randomized, controlled clinical trial comparing recombinant human bone morphogenetic protein 2/absorbable collagen carrier and collagen sponge alone. Recommendations for conducting controlled clinical studies of dental restorative materials Ridge Preservation for Implant Therapy: a Review of the Literature Physical activity and strength of the femoral neck during the adolescent growth spurt: a longitudinal analysis. Five-year evaluation of the influence of keratinized mucosa on peri-implant soft-tissue health and stability around implants supporting full-arch mandibular fixed prostheses. Clinical evaluation of a dermic allograft in procedures to increase attached gingiva width. Comparison of panoramic and conventional cross-sectional tomography for preoperative selection of implant size. Ridge preservation comparing socket allograft alone to socket allograft plus facial overlay xenograft: a clinical and histologic study in humans. Periodontal regeneration versus extraction and prosthetic replacement of teeth severely compromised by attachment loss to the apex: 5-year results of an ongoing randomized clinical trial. Effects of oral chondroitin sulfate on the progression of knee osteoarthritis: a pilot study.
BACKGROUND Previous surgical crown lengthening studies have investigated positional changes of the free gingival margin but not the biological width . Histological studies utilizing animal models have shown that postoperative crestal resorption allowed reestablishment of the biological width . However , very little work has been done in humans . Therefore , the purpose of this study was to evaluate the positional changes of the periodontal tissues , particularly the biological width , following surgical crown lengthening in human subjects . METHODS Twenty-three ( 23 ) patients who needed surgical crown lengthening to gain retention necessary for prosthetic treatment and /or to access caries , tooth fracture , or previous prosthetic margins entered the study . The following parameters were obtained from line angles of treated teeth ( teeth requiring surgical crown lengthening ) and adjacent teeth with adjacent and non-adjacent sites : plaque and gingival indexes , free gingival margin , probing depth , attachment level , bone level , direct bone level , and biological width . During surgery , the bone level was reduced based on the future prosthetic margin and predetermined biological width ; flaps were placed at the bony crest . Patients were examined at baseline and at 3 and 6 months postoperatively . RESULTS Eighteen patients completed the study . Overall , the amount of bone resected was 1 to 5 mm . At 90 % of treated sites , > or = 3 mm of bone was removed . At 3 months , the apical displacement of the free gingival margin at non-adjacent , adjacent , and treated sites was 2.46 + /- 0.25 mm , 2.68 + /- 0.20 mm , and 3.07 + /- 0.16 mm , respectively . There was no significant change in the position of the free gingival margin from 3 to 6 months . The biological width at all sites was smaller at 3 and 6 months compared to baseline ( P<0.05 ) except for the treated sites , which were not significantly different from baseline at 6 months . CONCLUSIONS During surgical crown lengthening , the bone level was lowered for placement of the prosthetic margin and reestablishment of the biological width . The biological width , at treated sites , was reestablished to its original vertical dimension by 6 months . In addition , a consistent 3 mm gain of coronal tooth structure was observed at the 3- and 6-month examinations The aim of this prospect i ve clinical 2-year study was to determine whether the placement of the proximal margins of crowns within the zone of the biologic width results in periodontal alterations . In 41 patients , 116 prepared teeth as well as 82 unrestored , healthy contralateral teeth were examined . The following indices were determined before as well as 3 , 6 , 12 , and 24 months after preparation :  hygiene index , papillary bleeding index ( PBI ) , and probing depth .  After preparation , the distance between the restoration margins and the alveolar crest was measured with a modified periodontal probe on both proximal aspects of each tooth . These values were classified into 3 groups : I = < or = 1 mm between crown margin and alveolar crest , II = 1 to 2 mm , and III = > 2 mm . In addition , radiographs were taken directly after cementation of each restoration and after 12 and 24 months . The hygiene index did not significantly vary during the investigation , but PBI increased in all groups . The highest PBI increase was found in group I ; in this group , the most significant increase was found between 3 and 6 months after preparation . The mean probing depth only increased in group I during the first 3 months after preparation on the mesial aspects . Only minor changes were found on the distal aspects of the teeth in group I and on all aspects in groups II and III . No alterations of the bone levels were diagnosed on the radiographs . These results indicate that the location of the restoration margins within the zone of the biologic width may impair the periodontal health of restored teeth PURPOSE / AIM Evaluate differences in bone remodeling , soft tissue reactions and biological width formation around immediate implants placed at different level in relation to the crestal bone in beagle dogs . MATERIAL AND METHODS The m and ibular second , third and fourth premolars of six beagle dogs were extracted , and three implants were placed in the right side of each dog . Healing abutments were adjusted ( n = 18 ) . After 4 weeks , the procedure was repeated on the left side of the m and ible ( n = 18 ) . R and omly , three implants were placed at crestal level ( control group ) , and three implants were placed 2 mm subcrestally ( test group ) in relation to the crestal bone in each animal . The dogs were sacrificed after 8 weeks from the first surgical procedure , and biopsies were obtained . Sample s were processed for ground sectioning . Histometric analysis was carried out to compare buccal and lingual bone resorption , soft tissue behavior and biological width formation in both groups . RESULTS Crestal bone resorption was higher in the test group when considering the difference of 2 mms ( IS-B = 2.05 ± 0.36 mm , control ; 1.75 ( + 2 ) ± 0.38 mm , test ) . However , the dimensions of the biological width were similar for both groups ( PM-C = 3.34 ± 0.53 mm , control ; 3.13 ± 0.55 mm , test ) . CONCLUSIONS The alterations that occurred in the peri-implant soft tissues may be related to the hard tissue remodeling , showing similar quantitative findings in the biological width formation in both groups . Even though the subcrestal placement might reduce the distance from the implant shoulder to the first bone-to-implant contact and reestablish the biological width dimension in a most coronal position , it might not have any effect on minimizing the marginal bone loss BACKGROUND An adequate width of attached gingiva is necessary to maintain healthy periodontium , especially in orthodontics or restorative treatments in periodontics . The purpose of this study was to evaluate the width of attached gingiva after clinical application of a cultured gingival graft compared to a periosteal fenestration technique . METHODS This study was conducted on nine patients ( 18 sites ) with insufficient attached gingiva adjacent to at least two teeth in contralateral quadrants of the same jaw . A small portion ( approximately 3 x 2 x 1 mm ) of attached gingiva ( epithelial + connective tissue ) was removed with a surgical blade . After culture of gingival fibroblasts , 2 x 10(5 ) cells in 250 microl nutritional medium were added to 250 microl collagen gel . One tooth in each patient was r and omized to receive a periosteal fenestration technique for gingival augmentation ( control ) or a tissue-engineered mucosal graft ( test ) . Clinical parameters measured at baseline and 3 months included width of keratinized tissue , probing depth , and width of attached gingiva . RESULTS An increased amount of keratinized tissue was seen at all treated sites after 3 months . The mean increased amount of attached gingiva was 2.8 mm at test sites and 2 mm at control sites ; this difference was significant ( P < 0.05 ) . CONCLUSION Based on the results of this investigation , the tissue-engineered mucosal graft is safe and capable of generating keratinized tissue BACKGROUND Animal and human research es have shown that immediate implant placement into extraction sockets failed to prevent socket dimensional changes following tooth extraction . It has been suggested that a minimal width of 1 - 2 mm of buccal bone is necessary to maintain a stable vertical dimension of the alveolar crest . AIM To determine the dimensions of the bony wall at extraction sites in the esthetic zone ( anterior teeth and premolars in the maxilla ) and relate it to immediate implant placement . METHODS As part of an ongoing prospect i ve r and omized-controlled multicenter clinical study on immediate implant placement , the width of the buccal and palatal bony walls was recorded at 93 extraction sites . RESULTS The mean width of the buccal and palatal bony walls was 1 and 1.2 mm , respectively ( P<0.05 ) . For the anterior sites ( canine to canine ) , the mean width of the buccal bony wall was 0.8 mm . For the posterior ( premolar ) sites , it was 1.1 mm ( P<0.05 ) . In the anterior sites , 87 % of the buccal bony walls had a width < or = 1 mm and 3 % of the walls were 2 mm wide . In the posterior sites , the corresponding values were 59 % and 9 % , respectively . CONCLUSIONS If the criterion of a minimal buccal bone width of 2 mm to maintain a stable buccal bony wall is valid , only a limited number of sites in the anterior maxilla display such a clinical situation . The data suggested that in the majority of extraction sites in the anterior maxilla , thin ( < or = 1 mm ) buccal walls were present . This , in turn , means that in most clinical situations encountered , augmentation procedures are needed to achieve adequate bony contours around the implant AIM The aim of this study was to test a new collagen matrix ( CM ) aim ed to increase keratinized gingiva/mucosa when compared with the free connective tissue graft ( CTG ) . MATERIAL AND METHODS This r and omized longitudinal parallel controlled clinical trial studied 20 patients with at least one location with minimal keratinized tissue ( < or=1 mm ) . MAIN OUTCOME MEASURE The 6-month width of keratinized tissue . As secondary outcomes , the aesthetic outlook , the maintenance of periodontal health and the patient morbidity were assessed pre-operatively at 1 , 3 and 6 months . RESULTS At 6 months , the CTG attained a mean width of keratinized tissue of 2.6 ( 0.9 ) mm , while the CM was 2.5 ( 0.9 ) mm , these differences being insignificant . In both groups , there was a marked contraction ( 60 % and 67 % , respectively ) although the periodontal parameters were not affected . The CM group had a significantly lower patient morbidity ( pain and medication intake ) as well as reduced surgery time . CONCLUSIONS These results prove that this new CM was as effective and predictable as the CTG for attaining a b and of keratinized tissue , but its use was associated with a significantly lower patient morbidity BACKGROUND The aim of this study was to evaluate the survival of dental implants  in periodontally susceptible patients using immediate loading/restoration ( ILR ) protocol s and the factors that modulate this response . METHODS Systemically healthy patients who were treated previously for chronic periodontitis and who required implant therapy were recruited . Following data collection , " surgical templates " and provisional fixed restorations were fabricated . Transgingival implants were inserted , and surgical measurements were performed . After abutment connection , the crown/bridge was relined and cemented . Patients were monitored for 12 months , at which time final measurements were performed . RESULTS Twenty patients ( 49 implants ) completed this study ; five implants failed and were removed ( 90 % survival rate ) . All implants were removed during the first 6 months . At 12 months , the mean implants ' probing depth was 2.87 + /- 0.9 mm . The mean electronic mobility testing device value ( -1.3 + /- 0.7 ) was slightly higher than at baseline ( -3.53 + /- 10.7 ) . Radiographic bone loss ranged between -1.24 and 2.77 mm ( mean + /- SD : 0.91 + /- 0.2 mm ) . All of the implants ( 16 ) that were inserted in the premolar region were successful , whereas three of nine implants in the molar region and two of 24 implants in the canine/incisor region failed ( P = 0.0278 ) . Survival in the immediately loaded group ( 83 % ) was slightly lower than in the immediately restored group ( 96 % ) ; however , these differences did not reach statistical significance . None of the other variables ( smoking , arch , stability , implant length and diameter , and bone width ) affected the outcome of this procedure . CONCLUSIONS ILR protocol s are predictable alternatives in periodontally susceptible patients . Results in the molar regions suggested that careful consideration should be given to implants placed in these sites . Long-term success in these patients has not been addressed OBJECTIVE This prospect i ve r and omized match-paired controlled trial aim ed to evaluate the impact of implant platform diameter on marginal bone level around implants restored according to the platform switching ( PS ) concept . MATERIAL AND METHODS A total of 24 implants were examined in 12 patients . All patients received two adjacent implants inserted at the crestal level : 4.3 mm ( control group ) and 4.8 mm ( test group ) in diameter . Mesio-distal implant position was r and omly performed . According to the PS concept , for restoration , a 3.8 and 4.3 mm diameter abutment was used , respectively in the control and test groups , result ing , in both groups , with 0.25 mm of implant/abutment mismatching . Implant restorations were splinted . Eighteen months after final restoration , periapical st and ardized digital radiographs were taken to evaluate marginal bone level alterations after loading . The Wilcoxon Signed-Rank Test was selected to identify differences between groups . RESULTS At the last follow-up , control implants exhibited a mean bone loss value of 1.10 mm ( SD : 0.47 mm ) ; the test group showed a mean value of 1.09 mm ( SD : 0.08 mm ) . No statistically significant differences were found between test and control groups . CONCLUSIONS Within the limits of this study , the present results suggest that bone resorption is mostly related to biologic ( biologic width re-establishment ) rather than to biomechanical factors ( implant platform diameter ) . Furthermore long-term studies with a wider sample size are needed to confirm the platform diameter influence on hard tissue response around implants restored according to the PS concept OBJECTIVE Many biological variables , endodontic treatment factors , and restorative considerations have been suggested in the literature to affect the outcome of endodontic treatment . However , few attempts have been made recently to study these variables further . The purpose of this study was to identify the biologic and endodontic treatment-associated variables that are most predictive of treatment outcome for conventional endodontic therapy and to determine the magnitude of risk these variables pose on the outcome . STUDY DESIGN The population of this historical prospect i ve cohort study comprised a total of 200 teeth with 441 root canals . Diagnostic and treatment information was abstract ed from the original patient records . An endodontic follow-up examination was conducted 4 + /- 0.5 years after obturation . Each tooth/root was analyzed according to 3 indices of periradicular status at 2 time points . The main outcome measure was the presence of apical periodontitis . The criteria used for evaluation of the outcome were modified from Strindberg . Data were subjected to univariate and multivariate analysis . Logistic regression models were fit by using various clinical measures to determine which combination of biologic and treatment-associated factors best predicted treatment outcome . RESULTS The preoperative pulp diagnosis , the periapical diagnosis , the preoperative periapical radiolucency size , and the sex of the patients were revealed , by means of univariate analysis , to exert a significant influence on endodontic treatment outcome ( P < .05 ) . In the logistic regression model , the strongest effect on postoperative healing was the presence and magnitude of preoperative apical periodontitis . In the presence of this variable , no other factor contributed value to the prediction . The correct prediction of this model was 74.7 % ( P < .05 ) . CONCLUSION The major biologic factors influencing the outcome of endodontic treatment appear to be the extent of microbiological insult to the pulp and periapical tissue , as reflected by the periapical diagnosis and the magnitude of periapical pathosis BACKGROUND Platelet-rich plasma ( PRP ) contains a number of biologically active growth factors , and previous studies have reported conflicting ridge augmentation results . The primary aim of this r and omized , controlled , masked , clinical trial was to determine if PRP combined with a rapidly resorbing cancellous allograft would enhance the regenerative result compared with an allograft without PRP . METHODS Thirty-two patients with an edentulous ridge defect were sequentially entered into the study ; four were excluded from data analysis . Fourteen patients received a cancellous allograft ( CAN group )  and the other 14 received a cancellous allograft mixed with PRP ( PRP group ) . All 28 grafted sites were covered with a resorbable polylactide membrane . After elevation of a full-thickness flap , horizontal ridge dimensions were measured with a digital caliper at the crest and 5 mm apical to the crest . Vertical ridge dimensions were measured from a tooth-supported stent . All sites were reentered at 4 months , and a trephine core was obtained for histologic analysis before implant placement . RESULTS The crestal ridge width for the CAN group had a mean gain of 2.0 ± 1.2 mm , whereas the PRP group gained 2.9 ± 1.0 , and the difference was statistically significant between groups ( P < 0.05 ) . The percent vital bone was 36 % ± 14 % for the CAN group compared with 51 % ± 15 % for the PRP group and was statistically significant between groups ( P < 0.05 ) . Loss of augmented ridge width was 34 % ± 17 % for the CAN group and 28 % ± 17 % for the PRP group ( P > 0.05 ) . CONCLUSION These clinical and histologic findings suggest that PRP  enhanced bone regeneration and result ed in increased horizontal bone gain and percentage vital bone Background Recurrent defects after open and arthroscopic rotator cuff repair are common . Double-row repair techniques may improve initial fixation and quality of rotator cuff repair .  Purpose To evaluate the load to failure , cyclic displacement , and anatomical footprint of 4 arthroscopic rotator cuff repair techniques .  Hypothesis Double-row suture anchor repair would have superior structural properties and would create a larger footprint compared to single-row repair . Study Design Controlled laboratory study . Methods Twenty fresh-frozen cadaveric shoulders were r and omly assigned to 4 arthroscopic repair techniques . The repair was performed as either a single-row technique or 1 of 3 double-row techniques : diamond , mattress double anchor , or modified mattress double anchor . Angle of loading , anchor type , bone mineral density , anchor distribution , angle of anchor insertion , arthroscopic technique , and suture type and size were all controlled . Footprint length and width were quantified before and after repair . Displacement with cyclic loading and load to failure were determined . Results There were no differences in load to failure and displacement with cyclic loading between the single-row repair and each double-row repair . All repair groups demonstrated load to failure greater than 250 N. A significantly greater supraspinatus footprint width was seen with double-row techniques compared to single-row repair . Conclusions The single-row repair technique was similar to the double-row techniques in load to failure , cyclic displacement , and gap formation . The double-row anchor repairs consistently restored a larger footprint than did the single-row method . Clinical Relevance The arthroscopic techniques studied have strong structural properties that approached the reported performance of open repair techniques . Double-row techniques provide a larger footprint width ; although not addressed by this study , such a factor may improve the biological quality of repair Extraction of a tooth necessitated by factors such as developmental problems , trauma , severe periodontal disease and endodontic problems often causes deformities of the residual alveolar ridge in the maxillary anterior region . These cases are usually difficult to restore prosthetically and they result in poor esthetics and insufficient occlusal function . This study investigated the efficacy of root form bioactive glass cones implanted into ( a ) artificial sockets produced by bone splitting of previous extraction sites ( group BS ) and ( b ) fresh extraction sockets ( group FES ) . We included conventional extraction sockets sutured without implanting the root form bioactive glass cones as a control ( group C ) . A total of 16 patients were treated for whom extraction s had been indicated due to severe periodontitis . 6 patients with 7 implant sites having Class II or III alveolar ridge deformities comprised the BS group . 5 patients with 10 implant sites comprised the FES group . Group C , comprised 5 patients with 10 extraction sites .  Alveolar ridge width and height measurements were obtained using study casts preoperatively , immediately postoperatively , and at 3 and 12 months after operation . In the BS group , while the width of the alveolar ridge increased by 2.8+/-1.18 mm immediately after ridge augmentation procedure and by 2.4+/-0.93 mm at 1 year after operation ( p<0.01 ) , the height of the alveolar ridge increased by 1.8+/-1.99 mm and 1.4+/-1.74 mm respectively ( p<0.05 ) . In the FES group , the differences between preoperative original ridge height and width and postoperative measurements were not statistically significant , which demonstrated the efficiency of this method in preserving the alveolar ridge . In group C , while alveolar ridge width after 12 months had not significantly changed , alveolar ridge height decreased significantly ( 1.35+/-1.05 mm , p<0.01 ) . After 12 months , no dehiscences were detected and the differences in height between the groups remained significant . The results of this study indicate that this procedure is efficient in reconstructing alveolar ridges deformed as a result of extraction , particularly relevant in relation to preparation for subsequent restorative treatment BACKGROUND Tooth extraction typically leads to loss of ridge width and height . The primary aim of this 6-month r and omized , controlled , blinded , clinical study was to determine whether ridge preservation would prevent post- extraction resorptive changes as assessed by clinical and histologic parameters . METHODS Twenty-four patients , 10 males and 14 females , aged 28 to 76 ( mean 51.5 + /- 13.6 ) , requiring a non-molar extraction and delayed implant placement were r and omly selected to receive either extraction alone ( EXT ) or ridge preservation ( RP ) using tetracycline hydrated freeze-dried bone allograft ( FDBA ) and a collagen membrane . A replaced flap , which did not completely cover the sockets , was used . Following extraction , horizontal and vertical ridge dimensions were determined using a modified digital caliper and an acrylic stent , respectively . Prior to implant placement , a 2.7 x 6.0 mm trephine core was obtained and preserved in formalin for histologic analysis . RESULTS The width of the RP group decreased from 9.2 + /- 1.2 mm to 8.0 + /- 1.4 mm ( P<0.05 ) , while the width of the EXT group decreased from 9.1 + /- 1.0 mm to 6.4 + /- 2.2 mm ( P<0.05 ) , a difference of 1.6 mm . Both the EXT and RP groups lost ridge width , although an improved result was obtained in the RP group . Most of the resorption occurred from the buccal ; maxillary sites lost more width than m and ibular sites . The vertical change for the RP group was a gain of 1.3 + /- 2.0 mm versus a loss of 0.9 + /- 1.6 mm for the EXT group ( P<0.05 ) , a height difference of 2.2 mm . Histologic analysis revealed more bone in the RP group : about 65 + /- 10 % versus 54 + /- 12 % in the EXT group . The RP group included both vital bone ( 28 % ) and non-vital ( 37 % ) FDBA fragments . CONCLUSIONS Ridge preservation using FDBA and a collagen membrane improved ridge height and width dimensions when compared to extraction alone . These dimensions may be more suitable for implant placement , especially in areas where loss of ridge height would compromise the esthetic result . The quantity of bone observed on histologic analysis was slightly greater in preservation sites , although these sites included both vital and non-vital bone . The most predictable maintenance of ridge width , height , and position was achieved when a ridge preservation procedure was employed BACKGROUND Flapless extraction of teeth allows for undisturbed preservation of the nearby periosteum and a source of osteoprogenitor cells . Recombinant human bone morphogenetic protein 2 ( rhBMP-2 ) has been used for different bone augmentation purpose s with great osteoinductive capacity . The aim of this study is to compare the bone regenerative ability of rhBMP-2 on an absorbable collagen sponge ( ACS ) carrier to a collagen sponge ( CS ) alone in extraction sites with ≥50 % buccal dehiscence . METHODS Thirty-nine patients requiring extraction of a hopeless tooth with ≥50 % buccal dehiscence were enrolled . After flapless extraction and r and omization , either rhBMP-2/ACS carrier or CS alone was placed in the extraction site . After extraction , a baseline cone beam computed tomography ( CBCT ) scan was obtained of the site , and a similar scan was obtained 5 months postoperatively . Medical imaging and viewing software were used to compare the baseline and 5-month postoperative images of the study site and assess ridge width measurements , vertical height changes , and buccal plate regeneration . RESULTS Radiographically , CBCT analysis showed that with ≥50 % of buccal bone destruction , rhBMP-2/ACS was able to regenerate a portion of the lost buccal plate , maintain theoretical ridge dimensions , and allow for implant placement 5 months after extraction . The test group performed significantly ( P < 0.05 ) better in regard to clinical buccal plate regeneration ( 4.75 versus 1.85 mm ) , clinical ridge width at 5 months ( 6.0 versus 4.62 mm ) , and radiographic ridge width at 3 mm from the alveolar crest ( 6.17 versus 4.48 mm ) after molar exclusion . There was also significantly ( P < 0.05 ) less remaining buccal dehiscence , both clinical ly ( 6.81 versus 10.0 mm ) and radiographically ( 3.42 versus 5.16 mm ) , at 5 months in the test group . Significantly ( P < 0.05 ) more implants were placed in the test group without the need for additional augmentation . The mean loss in vertical ridge height ( lingual/palatal ) was less in the test sites but was not significantly ( P = 0.514 ) different between the test and control groups ( 0.39 versus 0.64 mm ) . CONCLUSIONS rhBMP-2/ACS compared to CS alone used in flapless extraction sites with a buccal dehiscence is able to regenerate lost buccal plate , maintain theoretical ridge dimensions , and allow for implant placement 5 months later About 35 years ago , Ryge provided a practical approach to evaluation of clinical performance of restorative material s. This systematic approach was soon universally accepted . While that methodology has served us well , a large number of scientific method ologies and more detailed questions have arisen that require more rigor . Current restorative material s have vastly improved clinical performance and any changes over time are not easily detected by the limited sensitivity of the Ryge criteria in short term clinical investigations . However , the clinical evaluation of restorations not only involves the restorative material per se but also different operative techniques . For instance , a composite resin may show good longevity data when applied in conventional cavities but not in modified operative approaches . Insensitivity , combined with the continually evolving and non-st and ard investigator modifications of the categories , scales , and reporting methods , has created a body of literature that is extremely difficult to meaningfully interpret . In many cases , the insensitivity of the original Ryge methods is misinterpreted as good clinical performance . While there are many good features of the original system , it is now time to move to a more contemporary one . The current review approaches this challenge in two ways : ( 1 ) a proposal for a modern clinical testing protocol for controlled clinical trials , and ( 2 ) an in-depth discussion of relevant clinical evaluation parameters , providing 84 references that are primarily related to issues or problems for clinical research trials . Together , these two parts offer a st and ard for the clinical testing of restorative material s/ procedures and provide significant guidance for research teams in the design and conduct of contemporary clinical trials . Part 1 of the review considers the recruitment of subjects , restorations per subject , clinical events , validity versus bias , legal and regulatory aspects , rationale s for clinical trial design s , guidelines for design , r and omization , number of subjects , characteristics of participants , clinical assessment , st and ards and calibration , categories for assessment , criteria for evaluation , and supplemental documentation . Part 2 of the review considers categories of assessment for esthetic evaluation , functional assessment , biological responses to restorative material s , and statistical analysis of results . The overall review represents a considerable effort to include a range of clinical research interests over the past years . As part of the recognition of the importance of these suggestions , the review is being published simultaneously in identical form in both the “ Journal of Adhesive Dentistry ” and the “ Clinical Oral Investigations . ” Additionally an extended abstract will be published in the “ International Dental Journal ” giving a link to the web full version . This should help to introduce these considerations more quickly to the scientific community Healing of the extraction socket after tooth removal involves retention of the blood clot followed by a sequence of events that lead to changes in the alveolar process in a three dimensional fashion . This normal healing event results in a minimal loss of vertical height ( around 1 mm ) , but a substantial loss of width in the buccal-lingual plane ( 4 - 6 mm ) . During the first three months following extraction that loss has been shown to be significant and may result in both a hard tissue and soft tissue deformity affecting the ability to restore the site with acceptable esthetics . Procedures that reduce the resorptive process have been shown to be predictable and potentially capable of eliminating secondary surgery for site preparation when implant therapy is planned . The key element is prior planning by the dental therapist to act at the time of extraction to prevent the collapse of the ridge due to the loss of the alveolus . Several techniques have been employed as ridge preservation procedures involving the use of bone grafts , barrier membranes and biologics to provide a better restorative outcome . This review will explore the evidence behind each technique and their efficacy in accomplishing site preparation . The literature does not identify a single technique as superior to others ; however , all accepted therapeutic procedures for ridge preservation have been shown to be more effective than blood clot alone in r and omized controlled studies Loading of the femoral neck ( FN ) is dominated by bending and compressive stresses . We hypothesize that adaptation of the FN to physical activity would be manifested in the cross-sectional area ( CSA ) and section modulus ( Z ) of bone , indices of axial and bending strength , respectively . We investigated the influence of physical activity on bone strength  during adolescence using 7 years of longitudinal data from 109 boys and 121 girls from the Saskatchewan Paediatric Bone and Mineral Accrual Study ( PBMAS ) .  Physical activity data ( PAC-Q physical activity inventory ) and anthropometric measurements were taken every 6 months and DXA bone scans were measured annually ( Hologic QDR2000 , array mode ) . We applied hip structural analysis to derive strength and geometric indices of the femoral neck using DXA scans . To control for maturation , we determined a biological maturity age defined as years from age at peak height velocity ( APHV ) . To account for the repeated measures within individual nature of longitudinal data , multilevel r and om effects regression analyses were used to analyze the data . When biological maturity age and body size ( height and weight ) were controlled , in both boys and girls ,  physical activity  was a significant positive independent predictor of CSA and Z of the narrow region of the femoral neck ( P < 0.05 ) . There was no independent effect of physical activity on the subperiosteal width of the femoral neck . When leg length and leg lean mass were introduced into the r and om effects models to control for size and muscle mass of the leg ( instead of height and weight ) , all significant effects of physical activity disappeared . Even among adolescents engaged in normal levels of physical activity , the statistically significant relationship between physical activity and indices of bone strength demonstrate that modifiable lifestyle factors like exercise play an important role in optimizing bone strength during the growing years . Physical activity differences were explained by the interdependence between activity and lean mass considerations . Physical activity is important for optimal development of bone strength BACKGROUND The question of the importance of keratinized mucosa around dental implants for the prevention of peri-implant disease could not be answered in the relevant literature so far . OBJECTIVE To investigate the influence of peri-implant keratinized mucosa on long-term peri-implant soft-tissue health and stability over a period of 5 years . MATERIAL AND METHODS A total of 386 m and ibular dental implants were placed in 73 completely edentulous patients , and subsequently restored with fixed full-arch prostheses . At prosthesis delivery ( baseline ) and after 3 , 6 , 12 , 18 , 24 , 36 , 48 and 60 months , modified plaque index ( mPlI ) , modified sulcus bleeding index ( mBI ) , distance between implant shoulder and mucosal margin ( DIM ) and width of peri-implant keratinized mucosa ( KM ) were recorded . Statistical analysis included multivariate logistic regression , multivariate ordinal logistic regression , generalized estimating equations and Bonferroni 's correction . RESULTS Fifty-eight patients with 307 implants completed the 5-year study . Statistically significantly higher plaque accumulation on lingual sites ( mean mPlI 0.67 , SD 0.85 ) , bleeding tendencies on lingual sites ( mean mBI 0.22 , SD 0.53 ) and larger soft-tissue recession on buccal sites ( mean DIM -0.69 mm , SD 1.11 mm ) were found when the width of KM was < 2 mm , compared to sites with > or=2 mm of KM ( mean mPlI 0.40 , SD 0.68 , P=0.001 ; mean mBI 0.13 , SD 0.41 , P<0.01 ; mean DIM -0.08 mm , SD 0.86 mm , P<0.001 ) . The width of keratinized mucosa had no effect on bleeding tendency or plaque accumulation on buccal sites ( P>0.05 ) . CONCLUSION In patients exercising good oral hygiene and receiving regular implant maintenance therapy , implants with a reduced width of < 2 mm of peri-implant keratinized mucosa were more prone to lingual plaque accumulation and bleeding as well as buccal soft-tissue recession over a period of 5 years The aim of this study was to clinical ly evaluate the use of alloderm to increase the width of attached gingiva . Nine patients were selected . The inclusion criteria were : attached gingiva smaller than 1 mm ; Miller 's class I and II gingival recession ; patients able to attend control dental appointments ; absence of periodontal pocket and endodontic treatment in the neighboring area where the acellular dermal graft would be placed . The clinical evaluation included :  allograft shrinkage 7 , 14 , 21 , 30 , 60 and 90 days after surgery ; width of attached gingiva at the end of the study ; difference in color and mobility of allograft . Allograft shrinkage was calculated by comparing its area immediately after surgery to its areas in the other days . Five st and ardized photographs were taken , digitized and the allograft area was measured . Paired Student 's t-test was used to compare the clinical data ( alpha=0.05 ) . The mean allograft shrinkage 90 days after surgery was 90.43 % and the mean width was 1.27 mm . Difference in color was observed in only 1 subject and no allograft mobility was detected . The results showed a large shrinkage of allograft  90 days after its insertion , raising doubts as to its validity for increasing the width of attached gingiva OBJECTIVE To compare panoramic and conventional cross-sectional tomography for preoperative selection of implant size for three implant systems ( Brånemark , Straumann ( ® ) , 3i ) . MATERIAL AND METHODS Presurgical panoramic ( Pan ) and cross-sectional tomograms ( Tomo ) of 121 implant sites in 121 patients scheduled for single-tooth implant treatment were recorded ; in 70 of the Pans ( Pan-B ) , a metal ball was placed in the edentulous area . By means of dedicated software , an implant with subjectively determined proper dimensions for the respective site was outlined by manually placing four reference points in each image by three observers . Additionally , four reference points corresponding to the margins of the metal ball were manually placed in Pan-Bs . The length and width of the implant were calculated after calibration to the reference ball ( true magnification ) in Pan-Bs and to a " st and ard " calibration method in all images ( magnification factor 1.25 in Pans and 1.7 in Tomos ) . Based on the corrected dimensions , the nearest , smaller implant size was selected among those available in each of the three implant systems . RESULTS When comparing Pans with Tomos , selected implant size differed in on average 89 % of the cases . The length differed in 69 % and the width in 66 % . Implants planned on Tomos were longer than those planned on Pans in 47 % and narrower in 30 % ( < 10 % in posterior regions ) . The Straumann ( ® ) system , with the smallest range of available implant sizes was significantly less affected by the radiographic method compared with the other two systems . CONCLUSION The selected implant size differed considerably when planned on panoramic or cross-sectional tomographs BACKGROUND Previous studies of ridge preservation showed a loss of ≈18 % or 1.5 mm of crestal ridge width in spite of treatment . The primary aim of this r and omized , controlled , masked clinical trial is to compare a socket graft to the same treatment plus a buccal overlay graft , both with a polylactide membrane , to determine if loss of ridge width can be prevented by use of an overlay graft . METHODS Twelve patients who served as positive controls received an intrasocket mineralized cancellous allograft ( socket group ) , and 12 patients received the same socket graft procedure plus buccal overlay cancellous xenograft ( overlay group )  . Horizontal ridge dimensions were measured with a digital caliper , and vertical ridge changes were measured from a stent . Before implant placement , at 4 months , a trephine core was obtained for histologic analysis . RESULTS The mean horizontal ridge width at the crest for the socket group decreased from 8.7 ± 1.0 to 7.1 ± 1.5 mm for a mean loss of 1.6 ± 0.8 mm ( P < 0.05 ) , whereas the same measurement for the overlay group decreased from 8.4 ± 1.4 to 8.1 ± 1.4 mm for a mean loss of 0.3 ± 0.9 mm ( P > 0.05 ) . The overlay group was significantly different from the socket group ( P < 0.05 ) . Histologic analysis revealed that the socket group had 35 % ± 16 % vital bone , and the overlay group had 40 % ± 16 % ( P > 0.05 ) . CONCLUSIONS The overlay treatment significantly prevented loss of ridge width and preserved or augmented the buccal contour . The socket and overlay groups healed with a high percentage of vital bone AIMS Aim of this r and omized , long-term clinical trial was to compare clinical - and patient-based outcomes following periodontal regeneration or extraction and replacement of hopeless teeth with chronic perio-endo lesions and /or attachment loss to or beyond the apex . METHODS Fifty patients presenting with generalized severe periodontitis and at least one hopeless tooth to be extracted for periodontal reasons were entered in this study . The test treatment consisted in the application of a regenerative strategy to 25 hopeless teeth . The control treatment consisted in the extraction of the 25 hopeless teeth and their replacement with conventional or implant-supported fixed partial dentures . RESULTS In the control group , 14 teeth were replaced with implant-supported restorations , eight with tooth-supported bridges , two with Maryl and bridges , while one was not replaced . All fixed partial dentures survived the 5-year follow-up period and 83 % were free from biological complications . In the test group , 23 of the 25 regenerated teeth showed important clinical improvements : the two teeth with unsatisfactory outcomes were extracted at 1 year . The 23 successfully regenerated teeth ( 92 % ) were in good health and function at 5-year examination visit and 84 % did not develop biological complications during the recall period . All patients consistently reported comfort in function at the experimental test and control units . In the test group , average clinical attachment level gains were 7.7±2.8 mm , radiographic bone gain 8.5±3.1 mm , probing pocket depth ( PPD ) reduction 8.8±3 mm . Residual PPDs were 4±1.7 mm . Most of the regenerated teeth showed a decrease in tooth mobility . CONCLUSIONS Regenerative therapy can be applied at hopeless teeth and has the potential to change their prognosis ; it is a suitable alternative to extraction of severely compromised teeth with intra-bony defects to or beyond the root apex The aim of this study was to assess the clinical , radiological and biological efficacy and tolerability of the SYSADOA , chondroitin 4- and 6-sulfate ( CS , Condrosulf , IBSA , Lugano , Switzerl and ) , in patients suffering from knee osteoarthritis . This was a 1-year , r and omized , double-blind , controlled pilot study which included 42 patients of both sexes , aged 35 - 78 years with symptomatic knee OA . Patients were treated orally with 800 mg chondroitin sulfate ( CS ) per day or with a placebo ( PBO ) administered in identical sachets . The main outcome criteria were the degree of spontaneous joint pain and the overall mobility capacity . Secondary outcome criteria included the actual joint space measurement and the levels of biochemical markers of bone and joint metabolism . This limited study confirmed that chondroitin sulfate was well-tolerated and both significantly reduced pain and increased overall mobility capacity . Treatment with CS was also associated in a limited group of patients with a stabilization of the medial femoro-tibial joint width , measured with a digitized automatic image analyzer , whereas joint space narrowing did occur in placebo-treated patients . In addition , the metabolism of bone and joint assessed by various biochemical markers also stabilized in the CS patients whereas it was still abnormal in the PBO patients . These results confirm that oral chondroitin 4- and 6-sulfate is an effective and safe symptomatic slow-acting drug for the treatment of knee OA . In addition , CS might be able to stabilize the joint space width and to modulate bone and joint metabolism . This is the first preliminary demonstration that a SYSADOA might influence the natural course of OA in humans
No universal dimension of the biologic width appears to exist .
BACKGROUND Consideration of the biologic width in restorative dentistry seems to be important for maintaining periodontal health .
OBJECTIVE To evaluate the dimensions of the biologic width in humans .