Giulio Rasperini

Does placement of a connective tissue graft improve the outcomes of coronally advanced flap for coverage of single gingival recessions in upper anterior teeth? A multi‐centre, randomized, double‐blind, clinical trial

AIMS This parallel-group, multi-centre, double-blind, randomized-controlled clinical trial was undertaken to compare the clinical outcomes and patient morbidity of coronally advanced flap (CAF) alone or in combination with a connective tissue graft (CAF+CTG) in single Miller Class I and II gingival recessions. MATERIAL AND METHODS Three centres enrolled 85 patients with one recession each. Surgery was performed elevating a pedicle flap; 42 sites randomly received a graft under the flap. Measurements were taken by blind and calibrated examiners. Outcome measures included recession reduction, complete root coverage (CRC), intra-operative and post-operative morbidity, dentine sensitivity, and side effects. RESULTS No differences were noted in the intra-operative and post-operative patient-related variables between the two groups. Surgical time was significantly shorter in the CAF group. Recession reduction was not statistically different between the two groups, even though a model showed a tendency towards improved outcomes in sites treated with CAF+CTG (adjusted difference 0.33 mm, 95% CI=-0.06 to 0.72, p=0.1002). Significantly greater probability of CRC was observed after CAF+CTG (adjusted OR=5.09, 95% CI=1.69-17.57, p=0.0033). Dentine hypersensitivity improved in both the groups. CONCLUSIONS Both treatments were effective in providing a significant reduction of the baseline recession and dentine hypersensitivity, with only limited intra-operative and post-operative morbidity and side effects. Adjunctive application of a CTG under a CAF increased the probability of achieving CRC in maxillary Miller Class I and II defects.

Platelet-derived growth factor applications in periodontal and peri-implant bone regeneration

Introduction: Achieving successful tissue regeneration following traditional therapeutic protocols, combining bone grafts and barrier membranes, may be challenging in certain clinical scenarios. A deeper understanding of periodontal and peri-implant wound healing and recent advances in the field of tissue engineering have provided clinicians with novel means to obtain predictable clinical outcomes. The use of growth factors such as recombinant human platelet-derived growth factor-BB (rhPDGF) with biocompatible matrices to promote tissue regeneration represents a promising approach in the disciplines of periodontology and implantology. Areas covered: This review covers the basic principles of bone and periodontal regeneration, and provides an overview of the biology of PDGF and its potential to predictably and reproducibly promote bone regeneration in regular clinical practice. The results of preclinical and clinical human studies evaluating the effectiveness of growth-factor-enhanced matrices are analyzed and discussed. Expert opinion: Current available evidence supports the use of rhPDGF-enhanced matrices to promote periodontal and peri-implant bone regeneration.

Advanced reconstructive technologies for periodontal tissue repair

Reconstructive therapies to promote the regeneration of lost periodontal support have been investigated through both preclinical and clinical studies. Advanced regenerative technologies using new barrier-membrane techniques, cell-growth-stimulating proteins or gene-delivery applications have entered the clinical arena. Wound-healing approaches using growth factors to target the restoration of tooth-supporting bone, periodontal ligament and cementum are shown to significantly advance the field of periodontal-regenerative medicine. Topical delivery of growth factors, such as platelet-derived growth factor, fibroblast growth factor or bone morphogenetic proteins, to periodontal wounds has demonstrated promising results. Future directions in the delivery of growth factors or other signaling models involve the development of innovative scaffolding matrices, cell therapy and gene transfer, and these issues are discussed in this paper.

A 10-year retrospective analysis of radiographic bone-level changes of implants supporting single-unit crowns in periodontally compromised vs. periodontally healthy patients

AIM To compare the 10-year peri-implant bone loss (BL) rate in periodontally compromised (PCP) and periodontally healthy patients (PHP) around two different implant systems supporting single-unit crowns. MATERIALS AND METHODS In this retrospective, controlled study, the mean BL (mBL) rate around dental implants placed in four groups of 20 non-smokers was evaluated after a follow-up of 10 years. Two groups of patients treated for periodontitis (PCP) and two groups of PHP were created. For each category (PCP and PHP), two different types of implant had been selected. The mBL was calculated by subtracting the radiographic bone levels at the time of crown cementation from the bone levels at the 10-year follow-up. RESULTS The mean age, mean full-mouth plaque and full-mouth bleeding scores and implant location were similar between the four groups. Implant survival rates ranged between 85% and 95%, without statistically significant differences (P>0.05) between groups. For both implant systems, PCP showed statistically significantly higher mBL rates and number of sites with BL> or =3 mm compared with PHP (P<0.0001). CONCLUSIONS After 10 years, implants in PCP yielded lower survival rates and higher mean marginal BL rates compared with those of implants placed in PHP. These results were independent of the implant system used or the healing modality applied.

3D-printed Bioresorbable Scaffold for Periodontal Repair

DOI: 10.1177/0022034515588303. Department of Biomedical, Surgical, and Dental Sciences, Unit of Periodontology, Foundation IRCCS Ca’ Granda Polyclinic, University of Milan, Milan, Italy; Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI, USA; Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, MI, USA; Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, South Korea; Department of Surgery, School of Medicine, University of Michigan, Ann Arbor, MI, USA; and Department of Mechanical Engineering, College of Engineering, University of Michigan, Ann Arbor, MI, USA; *corresponding author, wgiannob@umich.edu

A 10-year retrospective analysis of marginal bone-level changes around implants in periodontally healthy and periodontally compromised tobacco smokers

AIM to compare the 10-year marginal bone loss rates around implants supporting single-unit crowns in tobacco smokers with and without a history of treated periodontitis. MATERIALS AND METHODS in this retrospective controlled study, 40 tobacco smokers were divided into four groups of 10 patients each. Two groups of periodontally compromised (PC) patients and two groups of periodontally healthy (PH) patients were established. PC patients had been treated for their periodontal conditions before implant placement. All patients were enrolled in a regular, individually tailored maintenance care program. For the rehabilitation of PC and PH patients, two different types of implants were used (Nobel Biocare AB; Straumann Dental Implant System). The radiographic bone loss rate was calculated by subtracting the bone levels at the time of crown delivery from the bone levels at the 10-year follow-up. RESULTS the mean age, mean full-mouth plaque score and full-mouth bleeding score and implant location were similar for the four groups. Implant survival rates ranged between 70% and 100%, without statistically significant differences between the four groups (P>0.05). Implants placed in PC patients yielded statistically significantly higher marginal bone loss rates compared with those in PH patients (P<0.05), independent of the implant system used. CONCLUSION after 10 years, implants placed in tobacco smokers with a history of treated periodontitis and enrolled in a supportive therapy program yielded lower survival rates and higher marginal bone loss rates compared with those of implants placed in PH smokers. These outcomes were independent of the implant system installed or the healing modality applied.

Postextraction Alveolar Ridge Preservation: Biological Basis and Treatments

Following tooth extraction, the alveolar ridge undergoes an inevitable remodeling process that influences implant therapy of the edentulous area. Socket grafting is a commonly adopted therapy for the preservation of alveolar bone structures in combination or not with immediate implant placement although the biological bases lying behind this treatment modality are not fully understood and often misinterpreted. This review is intended to clarify the literature support to socket grafting in order to provide practitioners with valid tools to make a conscious decision of when and why to recommend this therapy.

Root Coverage Esthetic Score After Treatment of Gingival Recession: An Interrater Agreement Multicenter Study

BACKGROUND The root coverage esthetic score (RES) system was proposed for evaluating esthetic outcomes of root coverage procedures. The aim of this multicenter study is to assess the interrater agreement of the RES among expert periodontists. METHODS Eleven periodontists were selected in different clinical centers. Each operator had ≥15 years of experience in mucogingival surgery. Each periodontist was trained to use RES before the beginning of the study. Subsequently, baseline and post-treatment (6 months) photographs of 41 Class I and II gingival recessions in 41 patients were separately given to each operator who evaluated the outcomes according to the RES method. A two-way random interclass correlation coefficient and 95% confidence interval (CI) were used to assess the global interrater agreement for RESs. RESULTS The total interrater agreement for RESs was 0.92 (95% CI: 0.88 to 0.95), which indicated that an almost perfect agreement was achieved. CONCLUSION Tested individually by a group of periodontists, the RES seems to be a reliable method for assessing the esthetic outcomes of root coverage procedures.

120 Infrabony Defects Treated With Regenerative Therapy : Long Term Results

BACKGROUND The aim of this study is to evaluate the long-term benefits of regenerative therapy and which factors (i.e., smoking, oral hygiene, radiographic angle, tooth, clinical center, and biomaterial) influence results. METHODS A total of 120 infrabony defects were treated with guided tissue regeneration using bioabsorbable and non-resorbable membranes with grafts or enamel matrix derivative (EMD) proteins. At baseline, smoking, x-ray angle, probing depth (PD), recession, and clinical attachment level (CAL) were recorded. CAL was measured 1 year post-surgery and every 2 years for ≤16 years. The participation of patients in oral hygiene protocols was recorded. RESULTS The mean ± SD baseline CAL was 8.5 ± 2.3 mm, baseline PD was 7.8 ± 2.1 mm, and baseline x-ray angle was 31.8° ± 8.9°. One year post-surgery, CAL gain was 4.1 ± 2.1 mm. EMD was used in 47 defects, bioabsorbable membranes with deproteinized bovine bone were used in 41 cases, non-resorbable membranes were used in seven defects, bioabsorbable membranes and autogenous bone were used in five defects, and a combination was used in 20 defects. A total of 10% of subjects were smokers, and 20% of subjects did not participate in an oral hygiene program. The average follow-up was 9 years. A total of 90% teeth survival was achieved at 13 years, and CAL gain was maintained at 82% for 11 years. Statistical analyses demonstrated that smoking and oral hygiene maintenance influenced long-term outcomes. The x-ray angle, tooth, clinical center, and biomaterials did not influence results. CONCLUSIONS Regenerative therapy provided a high percentage of long-term success. Smoking and non-participation in oral hygiene maintenance negatively influenced the prognosis, whereas other factors did not affect long-term results.

Crestal bone changes at teeth and implants in periodontally healthy and periodontally compromised patients. A 10-year comparative case-series study.

BACKGROUND Limited data exist on the longitudinal crestal bone changes around teeth compared with implants in partially edentulous patients. This study sought to compare the 10-year radiographic crestal bone changes (bone level [BL]) around teeth and implants in periodontally compromised (PCPs) and periodontally healthy (PHPs) patients. METHODS A total of 120 patients were evaluated for the radiographic crestal BL around dental implants and adjacent teeth at time of implant crown insertion and at the 10-year follow-up. Sixty patients had a previous history of periodontitis (PCPs), and the remaining 60 were PHPs. In each category (PCP and PHP), two different implant systems were used. The mean BL change at the implant and at the adjacent tooth at the interproximal area was calculated by subtracting the radiographic crestal BL at the time of crown cementation from the radiographic crestal BL at the 10-year follow-up. RESULTS At 10 years after therapy, the survival rate ranged from 80% to 95% for subgroups for implants, whereas it was 100% for the adjacent teeth. In all eight different patient categories evaluated, teeth demonstrated a significantly more stable radiographic BL compared with adjacent dental implants (teeth BL, 0.44 ± 0.23 mm; implant BL, 2.28 ± 0.72 mm; P <0.05). Radiographic BL changes around teeth seemed not to be influenced by the presence or absence of advanced bone loss (≥3 mm) at the adjacent implants. CONCLUSIONS Natural teeth yielded better long-term results with respect to survival rate and marginal BL changes compared with dental implants. Moreover, these findings also extend to teeth with an initial reduced periodontal attachment level, provided adequate periodontal treatment and maintenance are performed. As a consequence, the decision of tooth extraction attributable to periodontal reasons in favor of a dental implant should be carefully considered in partially edentulous patients.