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PURPOSE A prospective cohort multicenter study was undertaken to identify risk factors for implant survival, complications, and patient-centered outcomes following single-tooth immediate implant placement and loading in esthetic areas. MATERIALS AND METHODS Consecutive immediate implants placed in incisors, canines, and premolar sites were included. Variables recorded as possible risk factors included smoking habit, systemic conditions or therapies, previous assumption of bisphosphonates, inability to take amoxicillin, untreated periodontitis, thin periodontium, parafunctional habits, suppuration, bone dehiscences, and buccal bone fracture during implant insertion. Outcome variables included implant survival, recession, other complications, and patient satisfaction. RESULTS Data of 215 implants in 215 patients were collected in 15 centers in 2 years. One implant was seated with a torque < 30 Ncm and was not immediately loaded. It was successfully loaded 10 weeks after placement and was healthy 2 years later. This implant was excluded from subsequent analysis. Potential risk factors were identified in 116 patients (54.21%). There were 11 dropouts after 1 year and 37 after 2 years. Failures were relatively frequent (14.6%) before the delivery of the definitive prosthesis. No significant association was observed between early failures and risk factors. One failure and six recessions were observed after the definitive prosthesis. High satisfaction scores (mean score of 9.47/10 and 9.55/10 for esthetics and function, respectively) were recorded at 2 years. No recession occurred in the no-risk group. Five mucositis cases and one peri-implantitis case were observed in the 2-year follow-up. CONCLUSION Failures were frequent before the definitive restoration and could not be explained by specific risk factors. Tissues appeared stable after the definitive restoration. Patients were very satisfied during the follow-up.

The aim of this study was to assess the combined role of current radiographic risk indicators and patient age in predicting lower lip sensitivity disturbances after surgical removal of impacted lower third molars. The question was which combinations indicate low or high risk. A prospective study was implemented involving 247 consecutive outpatients who underwent 423 surgical extractions. The predictor variables were patient age and risk indicators observed on panoramic radiographs. The outcome variable was the incidence of self-assessed lip sensitivity alterations. The extractions were subdivided into four groups according to the predictors. Two hundred forty-five teeth were extracted in patients younger than 25 years and 178 in patients 25 years old or older; radiographic risk indicators were associated with 226 out of 423 teeth (53.43%). No permanent neurological damage was observed. Transient lip sensitivity alterations were observed in five cases (1.18%; 95% confidence interval = 0.4 to 2.7%), all in the older group with radiographic risk indicators. The data indicate a low overall incidence of transient lip sensitivity impairment that occurred only in the presence of radiographic risk indicators in patients aged ≥ 25 years. Informed consent should include the possibility of inferior alveolar nerve injury in mature patients with radiographic risk indicators. Prophylactic removal of impacted teeth with radiographic signs of risk may be indicated when the patient is not yet aged 25 years.

The autogenous tooth transplantation approach to replace missing teeth has been in use for a long time. Different surgical techniques have been developed to improve prognosis and longevity of transplanted teeth with complete root formation. Many factors reportedly affected short- and long-term success of the procedure: complications such as ankylosis and root resorption up to the tooth exfoliation have occurred frequently. Several studies have appeared on this issue over the years. However, outcomes of transplantations have not yet been conclusively determined as no randomized clinical trials have been published on this issue, and their effectiveness has been evaluated only in observational studies. On the other hand, interesting information from specific experimental studies on the healing pattern of the interface between the root surface and alveolar bone in the replantation/transplantation model, and from non-related studies dealing with mechanically induced periodontal trauma, has been available and potentially useful since the 1970s to 1980s. However, this information has not been incorporated into clinical literature regarding tooth autotransplantation. This commentary aims to show how information from related and unrelated experimental models was translated to a clinical setting and led to a novel approach, successfully applied, in the autotransplantation of a multirooted tooth with completed root formation.

Background A new, computerized diagnostic tool, called the Longevity Protocol, was recently developed to predict implant failure. The present retrospective analysis was undertaken to assess the prognostic validity of this protocol. Materials and Methods A selected group of patients who had been treated with implants over the past 10 years at six dental clinics and experienced implant failure were included in the analysis. Another group of patients with similar characteristics, not experiencing implant failure, was used as control. In April of 2015, data about each of the patients was entered into the Longevity Protocol database. For each patient, the risk assessment produced by the protocol was compared to whether the implants eventually failed. The implant failure predictions and actual implant failures were compared. Results The Longevity Protocol analyzed the possible failure of 595 implants placed in 221 patients (323 implants placed in 138 patients classified as low risk, 180 implants placed in 55 patients classified as moderate risk, and 92 implants placed in 28 patients classified as high risk). The actual percentage of implant failure in the three groups was 10%, 15%, and 22%, respectively. The differences between the groups were statistically significant. The sensitivity and specificity of the Longevity Protocol was 84.9% and 11.90% in the high/moderate risk group and 47.17% and 32.74% in the low risk group, respectively. Conclusions Statistically significant results were obtained. The Longevity Protocol reliably identified patients who risked implant failure. The protocol appears to be an important tool for prognosis assessment.

Aim To investigate the aesthetic perception of the clinical outcomes of a simulated root coverage procedure in three different groups: patients, dentists, and periodontists. Material and methods 100 patients, 107 general dentists affiliated with the Dental Association of Prato, Italy, and 81 active members of the Italian Society of Periodontology were recruited for this study. The following variables: age, gender, level of education, place of residence, and years of practice (only for dentists and periodontists) were recorded by means of a questionnaire administered to each subject within the three different groups. In addition, the participants in the study were requested to assign scores to images of eight simulated clinical cases of gingival recessions: a pre- and post-treatment image for each case. Results Statistically significant differences between groups were not detected in most of the scores. Gender and residence were not significantly associated with the scores, while age was correlated for two clinical cases (p=0.0014 and 0.0017). All the cases of complete root coverage showed the highest scores among all the participants. Conclusions These results showed that complete root coverage following root coverage procedure is perceived as the most successful outcome by patients, dentists, and periodontists.

A new, computerized diagnostic tool, called the Longevity Protocol, was recently developed to predict implant failure. The present retrospective analysis was undertaken to assess the prognostic validity of this protocol.A selected group of patients who had been treated with implants over the past 10 years at six dental clinics and experienced implant failure were included in the analysis. Another group of patients with similar characteristics, not experiencing implant failure, was used as control. In April of 2015, data about each of the patients was entered into the Longevity Protocol database. For each patient, the risk assessment produced by the protocol was compared to whether the implants eventually failed. The implant failure predictions and actual implant failures were compared.The Longevity Protocol analyzed the possible failure of 595 implants placed in 221 patients (323 implants placed in 138 patients classified as low risk, 180 implants placed in 55 patients classified as moderate risk, and 92 implants placed in 28 patients classified as high risk). The actual percentage of implant failure in the three groups was 10%, 15%, and 22%, respectively. The differences between the groups were statistically significant. The sensitivity and specificity of the Longevity Protocol was 84.9% and 11.90% in the high/moderate risk group and 47.17% and 32.74% in the low risk group, respectively.Statistically significant results were obtained. The Longevity Protocol reliably identified patients who risked implant failure. The protocol appears to be an important tool for prognosis assessment.

Case presentation Systematic reviews play an increasingly important role in establishing recognized evidence to guide clinical decision making. The evidence is usually graded on a scale that depends on the reliability of the reviewed material. To take into account any factor affecting the reliability of the conclusions of articles dealing with treatment outcomes, the grading scales of JEBDP are continuously reviewed. The aim of this article is to propose a modification of the JEBDP grading system, to take into account the value of individual patient data (IPD). The availability of IPD may be crucial for assessing the reliability of a systematic review, especially when the influence of patient-related features affect the outcome of therapy. We use simulated and published data to illustrate the role of IPD in assessing the contribution of individual prognostic factors to the final outcome and in preventing ecological bias.

Systematic reviews of the literature are an increasingly important tool for providing evidence-based guidance to the practitioner. This review article and a companion paper deal with the surgical coverage of exposed root surfaces, but their aim is to promote a more up-to-date way of writing and publishing scientific articles in this field. This article presents the published data about surgical root coverage in table form and its aim is to identify updated minimum standards for data presentation.Manual and computer-assisted searches were conducted to find the articles published on this topic during the 30-year period from 1970 to 2000. Articles that described the surgical procedure and reported at least the number of treated recessions and the duration of the follow-up, including case series, controlled studies, and randomized trials were selected and data were arranged in tables.Only 90 of the 290 articles that dealt with root coverage met the entry criteria; 25 of these were found only through manual searching. The overall clinical outcomes of different techniques appear to be satisfactory, but the published evidence is of little help in deciding which procedure is best suited for each clinical situation. Only a more homogeneous way of collecting and reporting clinical data and especially outcome measures will allow for an effective reanalysis which could help in everyday clinical decision making. Perhaps studies should be carried out and presented keeping in mind that the published results of sound clinical studies will, sooner or later, be reviewed and compared with other studies.A standard format with minimum requirements for data collection and presentation should be established and imposed by international journals in order to provide readers and researchers with more useful information.

The objective of the study was to compare the clinical efficacy of 3 surgical approaches in the treatment of deep recession type defects. Fifty-four (54) gingival recessionsor = 5 mm were randomly assigned to 1 of the 3 treatment groups by blocking the prognostic variables. The first group was treated with a guided tissue regeneration (GTR) procedure using a bioabsorbable membrane, the second with non-resorbable membrane, and the third with a mucogingival surgical approach consisting of a connective tissue graft combined with a coronally advanced flap (bilaminar technique). No differences, in terms of baseline oral hygiene and defect characteristics, were observed among the 3 groups showing an effective blocking approach. The 1-year results indicated that 1) all treatment approaches resulted in clinically significant root coverage and attachment gain; 2) a statistically significant treatment effect (P = 0.012, ANOVA) was observed comparing the bioabsorbable (4.9+/-0.3 mm), the non-resorbable (4.5+/-0.8 mm), and the bilaminar (5.3+/-0.7 mm) groups, in terms of root coverage; 3) the difference in terms of root coverage between the bilaminar and the non-resorbable membrane groups was statistically significant while differences between the 2 GTR groups or between the bilaminar and the bioabsorbable membrane groups did not reach statistical value; 4) the 95% confidence intervals for the proportions of complete successes showed a similar pattern; 5) no statistical difference was demonstrated in the amount of attachment gain among the 3 groups (P=0.73, ANOVA). A regression model showed that the amount of root coverage was significantly affected by the initial recession depth, the procedure and smoking habits: a poorer root coverage result is expected in case of shallow recession type defects, when either bioabsorbable (P0.05) or non-resorbable (P0.001) membranes are used instead of a bilaminar technique and if the patient smokes (P0.01). It was concluded that the mucogingival bilaminar technique is at least as effective as GTR procedures in the treatment of gingival recessionor = 4 mm and thus recession depth is not the parameter which influences the selection of the surgical procedure.

The aim of this study was to review recent randomized clinical trials (RCTs) dealing with the effectiveness of various modalities of orthopaedic/orthodontic expansion of maxillary arches with crossbite and the associated 6 month post retention stability. The study selection criteria included RCTs involving subjects with maxillary deficiency with crossbite, with no limits of age. The authors searched the following electronic databases from 1999 to January 2011: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, LILACS, and WEB of SCIENCE. The search strategy resulted in 12 articles meeting the inclusion criteria. Most of the studies did not meet major methodological requirements; some studies were not relevant because of small sample size, possible bias and unaccounted for confounding variables, lack of blinding in measurements, and deficient statistical methods. Treatment outcomes were different depending on the appliance used, tooth tissue-borne/tooth-borne expanders, bonded semi-rapid maxillary expansion (SRME), or rapid maxillary expansion (RME); in any case, methodological flaws prevent any sound conclusion. Stable results have been measured at the 6 month follow-up after removal of the retention plate in the treated groups in the maxillary intermolar and intercanine distances. Long-term stability results should be assessed. The Consolidated Standards of Reporting Trials (CONSORT) Statement could be helpful in improving the reporting of RCTs.

A technique for fabricating a definitive immediate fixed implant-supported prosthesis to rehabilitate the edentulous mandible is described. Temporary abutments were used first as impression copings, later modified to achieve parallelism, and finally incorporated in the definitive framework. The metal framework was fabricated with holes for the abutments and connected to the abutments with composite resin cement intraorally to obtain passive fit. This technique reduced the number of steps, thereby decreasing insertion time of the definitive prosthesis to 2 days.

The aim of this survey is to assess the different radiographic interpretations of simulated dental implant cases among a group of specialists in oral surgery.A total of 76 active members of the Italian Society of Oral Surgery and Implantology were recruited for the study. The participants in the study were requested to assign scores to radiographic images of 12 simulated cases of dental implants: a baseline and follow-up image for cases with different bone loss (0, 1 or 5 mm), implant length (8 or 12 mm) and years of follow-up (1 or 5 years).In total, 63 active members agreed to participate in the survey. The inter-rater agreement was 0.86 (CI 95% 0.74; 0.95). In cases where the bone loss was absent (0 mm) no difference was detected at 1 or 5 years of follow-up. In contrast, when bone loss was present (1 or 5 mm) the longer follow-up (5 years) revealed the highest score. The lowest score was attributed to 5 mm of bone loss and 1 year of follow-up. Moreover, a significant difference between the short (8 mm) and the long (12 mm) implant was observed (score difference 0.45; CI 95% 0.28; 0.63).This investigation suggests that subjective evaluation of radiographs on simulated implants by skilled clinicians is rather uniform, and bone loss, follow-up and implant length are factors considered in the perception of implant success.

Nine localized buccal ridge deformities were treated combining the use of barrier membranes and resorbable space-making material. After elevating flaps, the bone defects were completely filled with calcium carbonate and a fibrin-fibronectin sealing system (FFSS). Membranes (Gore-Tex aug-mentation material) were then shaped and positioned to cover the calcium carbonate overlapping the surrounding bone. The flaps were sutured, taking care to avoid any compression on the treated area. The membranes were removed 4 to 5 months postoperatively: in all cases the membranes were tightly adapted to the regenerated tissues and force was required to separate them from the underlying tissues. The defects were filled with hard, bone-like tissue. The histology from one case, taken 1 year post-operatively, confirmed the regeneration of bone and revealed the presence of a few residual particles of calcium carbonate in the sample. The clinical appearance of the treated areas was satisfactory for colour. texture and form. The horizontal deficiencies were almost completely resolved in all cases, while the vertical component showed incomplete filling in some cases.

A surgical technique involving membranes was used to treat localized human buccal recessions 3 mm to 8 mm. The results on 25 patients (test group) were evaluated 18 months postoperatively and compared with the results obtained in 25 other patients (control group) having undergone mucogingival surgery. In the test group, a trapezoidal flap with a large base was raised beyond the mucogingival junction. The exposed root surface was scaled thoroughly to a concave shape. A membrane was bent and adapted onto the concave root surface. The flap was sutured far coronally and the membrane removed one month later. The control patients underwent a 2-step procedure, consisting of a free gingival graft and a coronally positioned flap. The amount of root coverage obtained was similar in the 2 groups (test = 72.73%; control = 70.87%), although the clinical attachment gain (test = 5.12 mm; control = 3.56 mm) and pocket variation (test = 1 mm reduction; control = 0.06 mm increase) differed significantly (P < 0.001). The keratinized tissue width was greater in the control group. The regression analysis showed that the amount of covered root surface after treatment was in strict correlation with the depth of the original recession in the test group, while no correlation was found in the control group. The expected root coverage was greater in the test group when the recession was greater than 4.98 mm, while it was greater in the control group when the recession was less than 4.98 mm. These results indicate that a guided tissue regeneration procedure can be used to successfully treat recession. The membrane procedure compared favorably with the mucogingival surgery in the treatment of deep recession.

Randomized controlled trials (RCTs) are considered the highest level in the hierarchy of evidence for treatment effectiveness. However, RCTs have also been criticized for various shortcomings. The purpose of this article was to review the most common criticisms against RCTs and answer them based on the principles of scientific inquiry, so that orthodontists can build their evidence-based practice on the best scientific research. In the era of evidence-based medicine, designing RCTs is the challenge for researchers in orthodontics.

An assessment of the factors affecting the clinical outcome of root coverage procedures may be useful in clinical decision making. The aim of this study is to investigate whether the post-surgical location of gingival margin relative to the cemento-enamel junction (CEJ) can influence the recession reduction (RecRed) and complete root coverage (CRC) following coronally advanced flap procedure (CAF).Sixty patients, aged between 22 and 57 years, 15 males and 45 females, each showing maxillary buccal recessions (or =2 mm) identified as Miller's Class I were consecutively enrolled. All the defects were treated by CAF procedure from 2000 to 2003 by a single operator with more than 20 years of clinical experience. Age, gender, smoking habits, and type of tooth of each patient were recorded. In addition, the following clinical data were measured or computed: recession depth, width of keratinized tissue, probing depth, distance between incisal margin (IM) and CEJ, dental hypersensitivity, clinical attachment level, distance between IM and gingival margin (IMGM), distance between IM and mucogingival junction (IMMG), and the location of gingival margin relative to the CEJ following CAF procedure (GM(1)). A multiple linear regression, and a logistic linear regression analyses were performed.The recession depth at baseline (Rec(T0)) and the location of the gingival margin after suturing (GM(1)) are positively correlated to recession reduction. Complete root coverage appeared to be influenced by GM(1): the more coronal the level of the gingival margin after suturing (GM(1)), the greater the probability of CRC.The location of the gingival margin relative to the cemento-enamel junction following CAF procedure seems to affect CRC.

The literature (1970-2000) on the outcome of surgical root coverage has been revised and summarized in a companion paper. The overall conclusion was that the various procedures are effective, but it was not possible to determine which procedure was best indicated in different clinical conditions. In this study, meta-analysis techniques were used to seek evidence for guiding clinical decisions when planning root coverage surgery. The aim of this study was to illustrate the differences between meta-analyses applied to summarized and individual patient data (IPD) and to present suggestions for reducing the costs of IPD meta-analysis.Only clinical trials and case series that included data on the number of teeth treated, baseline recession depth (BRD) and the proportions of postoperative complete root coverage (CRC) were considered. The first group of meta-analyses (the outcome of each procedure based on summarized data) covered 65 studies dealing with coronally advanced flap (CAF), epithelial free gingival graft (EFGG), connective tissue graft (CTG), and guided tissue regeneration (GTR) procedures. The second group of meta-analyses was done to determine the outcome of each procedure on the basis of 26 studies that reported IPD for at least baseline recession depth (BRD) and final CRC for each site. The third group of meta-analysis compared the outcomes of CTG and GTR in 5 randomized studies, 4 of which reported only summarized data.The first analysis showed that CRC was achieved more often in non-randomized than in randomized studies. The heterogeneity tests revealed great variability of results in both the randomized and non-randomized studies, which makes it difficult to draw any definite conclusions. In the second analysis all the tested techniques revealed similar trends: greater baseline recession depths were always associated with a decreased CRC. The third analysis showed that CRC was achieved more frequently in the sites treated with CTG as opposed to GTR. The small sample size and the lack of IPD rendered the analyses inconclusive despite the randomized design.Few studies reported individual patient data; they are a valuable contribution to clinical decision making, but IPD published in the literature are still insufficient to provide a reliable guide for clinical decision making. Therefore, decisive steps should be taken to facilitate the publication of IPD, in electronic format, whenever a clinical study is published in a leading journal.

Different membrane materials accumulate varying amounts of bacteria when exposed in the oral cavity, due to their textural and structural surface characteristics. The aim of the study was to evaluate the effect of chlorhexidine mouthrinses on the in vivo early bacterial colonization of 3 different guided tissue regeneration membrane materials.Rectangular-shaped strips cut from 3 periodontal membranes (expanded polytetrafluoroethylene, polyglactin 910, and polylactic acid) were glued to removable devices adapted to the 2 upper quadrants in 8 dental students. In each student 1 quadrant was randomly selected as test side while the other served as control side. The experiment was divided in 2 phases: in the first phase plaque accumulation was followed for 4 hours while the second accumulation was followed for 24 hours. During the 4-hour experiment, students rinsed the test device twice (immediately following device application and after 2 hours) with 0. 12% chlorhexidine solution. The control device was rinsed with saline. In the second phase, students rinsed the test device with chlorhexidine and the control devices with saline 3 times (after device application and at 8 and 16 hours). Both the 4-hour and the 24-hour specimens were processed for scanning electron microscopy analysis. Fifty-four fields (at 200x magnification) were randomly selected and analyzed on each strip. Magnification was increased to determine the presence and morphotype of bacteria. The presence or absence of bacteria was assessed in a binomial fashion: the field was bacteria-positive when bacteria constituted the deposits covering the membrane surface. The microscopic field was negative (bacteria-negative) when no bacteria were observed. Bacteria-positive fields showing rods and filaments as prevalent morphotypes were recorded as rod-positive fields.The results of data analysis suggest that bacterial contamination of membrane materials is significantly reduced by treatment with chlorhexidine. They also suggest that other variables affect plaque accumulation as well; i.e., the time allowed (4 versus 24 hours) and the different membrane materials. The interaction between these 2 variables is also highly significant, thereby indicating a different rate of plaque accumulation on different materials, irrespective of the treatment with chlorhexidine.It was concluded that chlorhexidine mouthrinses may be effective in reducing and delaying the early bacterial accumulation on membrane materials although they are not able to fully prevent it. Membrane surface characteristics seem to be a more critical factor than the use of chlorhexidine, in influencing bacterial adhesion and colonization of barrier materials.

Summary Subjects All of the partially edentulous patients (660) treated with0689 Branemark implants in the departments of periodontology and prosthodontics at the Catholic University of Leuven between December 1982 and June 1998 were included in the study. The patients were followed up until June 1999 (1 to 16.5 years, with a mean follow-up duration of 5.5 years). There were 248 males and 412 females; ages ranged from 15 to 83 years with a mean of 50.5. A total of 1956 implants with different thread profiles were placed: 270 were intended to support single crowns and 1686 to serve for fixed partial prostheses. Medical problems, bone dehiscence at the time of installation, and use (in 170 sites) of membranes and/or autologous bone grafts or xenografts were not exclusion criteria. Exposure The relationship between failure rates and several 0689 prognostic variables was analyzed. Tested predictors included patient's sex and age; implant length and location (anterior, posterior, maxilla, mandible); splinting (subsequent single crowns vs fixed partial dentures); prosthetic connection with natural teeth; use of membranes and/or grafts; implant thread profile; number of implants and prostheses per patient; and number of implants supporting each prosthesis. Main outcome measure Cumulative failure rates, estimated by life table analysis,0689 served as the main outcome measure. Mobility, radiolucency, pain, infection, or fracture identified implant failure. Main results Higher implant failure rates were significantly associated 0689 with different variables, including (1) use of membranes and/or grafts (estimated hazard rate: 4.2 times the standard procedure; 95% confidence interval = 1.8; 9.6) and (2) short implants (decreasing length was associated with an increase in the hazard rate: estimated survival rate for implants was 81.5% for implants less than 10 mm long, 91% for implants 10 to 13 mm long, and 94.6% for longer implants).

This study compared the thermal distortion of all-ceramic crowns with porcelain-fused-to-metal crowns. The materials exhibited different responses: metal ceramic crowns stabilized after an initial loss of marginal precision, and the all-ceramic crowns continued to distort with each firing cycle.

A deep, long-standing recession on a mandibular incisor was treated in a 56-year-old female patient. The tooth was tilted buccally and was scheduled for extraction. The recession was 8 mm deep, with a pocket depth of 1 mm and no keratinized tissue. The recession was treated by guided tissue regeneration; the membrane was left in place for 4 weeks. The tooth was extracted along with marginal tissues 5 months after the removal of the membrane. At the time of extraction, 4 mm of root coverage had been achieved and 3 mm of keratinized tissue were measured buccally. Histologic measurements showed that 3.66 mm of new connective tissue attachment had been obtained associated with newly formed cementum (2.48 mm) and bone growth (1.84 mm). The crestal bone level after treatment was located coronal to the preoperative location of the gingival margin.

Activators of fibrinolysis are found in the gingival connective tissue and in the sulcular epithelium. The influence of plaque bacteria and the related inflammatory reaction on the fibrinolytic activity has been evaluated in the human gingiva. An autohistographic technique was applied to sections taken from three groups of 6 specimens each: group A from clinically healthy sites with plaque index = 1 and no bleeding on probing; group B from areas with unambiguous visual signs of gingivitis, with plaque index = 2-3 and bleeding on probing; group C from sites previously treated with professional toothcleaning twice a week for 3 months and with chlorhexidine mouthrinses twice a day for the final 3 wk, in order to obtain a virtually complete elimination of the plaque bacteria. In group C the plaque index was 0 and there was no bleeding on probing. Connective tissue fibrinolytic activity was present in all the sections from the three groups. The sulcular fibrinolytic activity was observed in all the sections taken from the specimens of groups A and B. In contrast, no fibrinolytic activity was observed over the sulcular area in any section taken from the specimens of group C. Therefore, this study does not support previous claims that healthy sulcular epithelium is capable of releasing activators of fibrinolysis. It can be concluded that the presence of any amount of plaque bacteria is associated with sulcular fibrinolytic activity. Contrarily, the elimination of plaque bacteria is associated with the absence of any detectable sign of fibrinolytic activity in the gingival sulcus.

A case is reported showing an iatrogenic, chronic abscess of six years' duration associated with a bony defect between the maxillary right central and lateral incisors. The osseous defect was treated by a guided tissue regeneration procedure with the use of a fibrin and fibronectin sealing system. The system was employed to fix the membranes and keep them apart from the root surface, thereby maintaining room for bone regeneration. This operation resulted in a 9-mm clinical attachment gain and in an 11-mm filling of the osseous defect. The second surgical stage after a three-month reentry procedure was strictly for cosmetic improvement by means of a free gingival graft.

Two sets of experimental linear osteotomies were performed on frozen cortical bone by means of a high-power industrial CO2 laser in the rapid superpulsed mode, varying the velocity of the operating table, the mean power of the laser beam, the pulsewidth, the pulse repetition rate, and the peak power. Both the depth and the width of the osteotomies were inversely related to the velocity and directly related to the mean power and to the pulsewidth, but they were not affected by changes in the repetition rate. The depth/width ratio, which describes the profile of the osteotomies, was affected by the mean power only. These data permit greater accuracy in the planning of laser osteotomies in cortical bone when using the rapid super-pulsed mode.

This study was undertaken to evaluate the effects of a commercially available tissue adhesive upon healing of the coronal periodontium. In four squirrel monkeys, 24 teeth were extracted, and the coronal third of the roots planed free of fibers and cementum. Eight teeth were replanted without further alteration and eight were coated with tissue adhesive prior to replantation. In the remaining eight teeth, the planed surface was decalcified, coated with tissue adhesive and replanted. Histological observations were made at 1 and 7 days after replantation. In the teeth replanted after root planing alone and root planing plus tissue adhesive, epithelium migrated apically and was within the ligament space lining the denuded root at 7 days. In contrast, those teeth which were decalcified prior to application of tissue adhesive demonstrated fiber attachment to the planed root surface and little or no epithelial downgrowth.

A fibrin-sealing system consisting of symmetrical flap and graft procedures versus silk sutures in a split-mouth clinical trial was tested in 51 patients. Clinical parameters and operative times were recorded and compared. In clinical use, the fibrin glue provided quick hemostasis and adequate tissue adhesion on the whole inner surface of grafts or flaps. Its use saved remarkable amounts of time and made it easier to fix tissues in difficult areas. The time saved ranged from 3 to 19.5 minutes per procedure, and 1 to 8.5 minutes per tooth. The convenience of the fibrin glue was especially appreciated in pedicle flap procedures.

The use of fibrin sealant (Tissucol) in periodontal surgery was tested in animal experiments, which showed an increase in the number of fibroblasts in the wound 3 days after surgery. No delay in wound healing was found on histologic sections. A clinical evaluation was also carried out, with a split-mouth design at first, and as a standard procedure later. Follow-up of 128 patients up to 3 years showed no adverse effect attributable to Tissucol. Instead hemostatic and adhesive qualities of the system facilitated surgery and shortened operating times, while wound healing appeared better in the first postoperative days.

A diagnostic technique to detect residual tissues at different levels of the root canal during an endodontic treatment is presented. The diagnostic system is based on ultraviolet-induced fluorescence spectroscopy and uses suitable optical fibers for local delivery of excitation light and to collect back fluorescence spectra. Spectra of root canal tissues have been obtained from split teeth by labeling with a fluorescent solution. Residual tissue can be discriminated in respect to healthy dentin because of their different spectral responses: the spectral shape of the first response shows a clear peak at 530 nm because of a selective absorption of the fluorescent dye, whereas for the second response, the spectral curve monotonically increases toward ultraviolet wave-lengths with no particular structure. This technique has been tested on unsplit teeth simulating operative conditions. A compact spectroscopic system has been devised that can be easily integrated in an excimer laser system to perform residual tissue detection during laser cleaning of the canals.

We report the first study of the application of excimer lasers in dentistry for the treatment of dental root canals. High-energy ultraviolet (UV) radiation emitted by an XeCl excimer laser (308 nm) and delivered through suitable optical fibers can be used to remove residual organic tissue from the canals. To this aim, UV ablation thresholds of dental tissues have been measured, showing a preferential etching of infiltrated dentin in respect to healthy dentin, at laser fluences of 0.5-1.5 J/cm2. This technique has been tested on extracted tooth samples, simulating a clinical procedure. Fibers of decreasing core diameters have been used to treat different sections of the root canal down to its apical portion, resulting in an effective, easy, and fast cleaning action. Possible advantages of excimer laser clinical applications in respect to usual procedures are also discussed.