Harvest graft substitute for soft tissue volume augmentation around existing implants: A randomized, controlled and blinded multicenter trial.

BACKGROUND: Using a single-blind, randomized, controlled, multicenter, practice-based clinical trial, a volume-stable collagen matrix (VCMX) was compared with connective tissue graft (CTG) for soft tissue augmentation around existing dental implants. METHODS: Sixty patients (31 VCMX and 31 CTG) were included. The primary outcome was a soft tissue thickness change 3 mm below the gingival margin (GM). Secondary outcomes included clinical measures, such as keratinized tissue widths (KTw), probing pocket depths, and pink esthetic scores, and patient-reported outcomes (PRO). RESULTS: There were no significant differences between test and control patient demographics or clinical measures throughout the 1-year study. VCMX "grafts" were by design larger than CTG, and surgery time was less (27% less, p = 0.0005). Three millimeters below the GM (primary endpoint), tissue thickness increase was noninferior for VCMX compared with CTG (0.93 ± 0.80 mm vs. 1.10 ± 0.51 mm, respectively), inferior (by 0.25 mm) at 1 mm, and noninferior at 5 mm. Postoperative pain was significantly less for VCMX patients (p < 0.0001), but all other PRO measures, including esthetics and satisfaction, improved similarly for both therapies. CONCLUSIONS: Given the inclusion criteria for this study, namely soft tissue augmentation around existing implants with some evidence of KTw and minimal recession, VCMX provided soft tissue thickness and volume increases similar (noninferior) to CTG. Clinical measures and PRO were similar between therapies-site sensitivity and esthetics improved similarly for both therapies-but surgery time and pain following surgery were significantly less for VCMX.

A Prospective, Randomized, Controlled, Multicenter Evaluation of Extraction Socket Management Comparing a Wound Dressing and a Soft Tissue Substitute.

Postextraction bone grafting and implant placement help preserve alveolar bone volume. Collagen wound dressings and soft tissue graft substitutes may help protect extraction socket bone grafts and provide better gingival contours. This randomized, controlled, multicenter, and double-blinded study was conducted to compare a control (wound dressing) and a test (soft tissue graft) substitute in nearly intact extraction sockets. Both test and control sockets were grafted with a xenogeneic bone graft. Graft containment, extraction socket soft tissue gap closure, gingival contour, and gingival thickness were examined over 16 weeks, at which time implants were placed. Healing was uneventful for both groups, and there was no significant difference (P < .05) between the times required to close the extraction socket soft tissue gap (~80% of sites closed by 8 weeks). Bone grafts were covered and contained longer in the test group (~4 weeks vs ~2 weeks), with less contour disruption out to 4 weeks; however, at implant placement, soft tissue contours in both groups were comparable, and soft tissue thicknesses were not significantly different.

The use of recombinant human platelet-derived growth factor-BB in combination with ß-tricalcium phosphate and rhPDGF-BB in combination with freeze-dried bone allograft plus barrier in two separate complex infrabony defects with long-term follow-up.

BACKGROUND: Reports from a large-scale, prospective, masked, randomized controlled clinical trial demonstrated gain in attachment level, linear bone gain, and percentage bone fill in infrabony defects treated with recombinant human platelet-derived growth factor-BB (rhPDGF-BB) and ß-tricalcium phosphate (ß-TCP) at 6 months. A follow up to that trial at 24 months showed the results were stable in terms of gain in clinical parameters, and assessment of selective cases demonstrated stability at 5 years. The cases presented in this report provide clinical applications to support the use of this biologic in complex infrabony defects. An infrabony defect is described as a periodontal pocket with its base apical to the crest of the alveolar bone. Infrabony defects may have one, two, or three bony walls creating challenges in management. METHODS: Two complex infrabony defect cases are presented in this report: one using rhPDGF-BB with ß-TCP and the other using rhPDGF-BB with freeze-dried bone allograft (FDBA) and a resorbable barrier membrane. The techniques are described with results showing long-term follow up and reentry at 8 and 14 years (respectively). RESULTS: Both cases demonstrate significant gains in clinical attachment levels as well as bone-like fill as observed radiographically and at reentry. CONCLUSIONS: These case reports of combining rhPDGF-BB with ß-TCP or with FDBA and a barrier membrane support the literature showing improvement in attachment levels and demonstrating bone fill in complex infrabony defects. The results can be maintained long term.

Application of enamel matrix derivative in conjunction with non-surgical therapy for treatment of moderate to severe periodontitis: A 12-month, randomized prospective, multicenter study.

BACKGROUND: Treatment of periodontitis aims to halt progressive bone and attachment loss and regenerate periodontal structures. In this study, the effect of using an enamel matrix derivative (EMD) as an adjunct to non-surgical periodontal therapy (test) versus non-surgical therapy alone (control) was evaluated. METHODS: A prospective, split-mouth, multicenter study evaluated scaling and root planing (SRP) with and without EMD in 51 patients presenting with moderate to severe periodontitis (PPD = 5 to 8 mm) in at least 2 pockets per contralateral quadrants within the same arch. The primary outcome variable was change in clinical attachment level (CAL) after 12 months. Secondary variables included probing pocket depth (PPD), bleeding on probing (BoP), gingival margin level, dentin hypersensitivity, and percent of pockets converted to sites no longer requiring surgical treatment. RESULTS: CAL changed significantly (P  < 0.001) from baseline to 12 months for both treatment modalities (test = -2.2 ± 1.5 mm versus control = -2.1 ± 1.3 mm) and similarly for PPD; the difference between groups was not significant. A significant difference, favoring test conditions, was observed in percentage of both healthy PPDs (pockets < 5 mm) and converted pockets (sites no longer requiring surgical treatment); 79.8% of test versus 65.9% of control sites. BoP decreased significantly more (P < 0.05) in test sites (BoP at 17.8% test versus 23.1% control). CONCLUSIONS: Both test and control treatments resulted in significant improvements in CAL and PPD. The adjunct use of EMD with SRP resulted in significantly greater improvements in overall periodontal health with less frequent BoP and a higher number of healthy PPDs.

Evaluation of a porcine collagen matrix used to augment keratinized tissue and increase soft tissue thickness around existing dental implants.

Implant-supported prostheses often present with mucogingival deficiencies that may cause esthetic or hygienic issues. These issues may present as limited or no keratinized tissue, irregular soft tissue contour or concavity, and gray "showthrough" of the implant abutment and root forms. An interpositional soft tissue graft substitute that generates keratinized tissue and increases soft tissue thickness would be beneficial, as it would reduce donor site morbidity and be available in unlimited, off-the-shelf supply. Thirty patients were assessed as part of a multicenter, practice-based evaluation of the material. A xenogeneic collagen matrix was placed as an interpositional graft on the buccal aspect of implant sites; sites were reassessed at 6 months posttreatment. Results indicated that the collagen matrix increased tissue thickness and keratinized tissue around existing dental implants.

Maintenance: the key to successful periodontal and implant therapy.

The management of periodontal diseases requires an effective treatment and maintenance program, as well as collaboration among clinicians. Having a better understanding of the factors contributing to periodontal maintenance is key. The components of a maintenance program and determining proper intervals ensure that patients increase their chances for maintaining their teeth and implants in an optimal state of health.

Periodontal regeneration: management of periodontal osseous defects by the periodontist-dental hygienist team.

UNLABELLED: Periodontal health can be restored through assessment, diagnosis, treatment and management of periodontal osseous defects by the periodontist-dental hygienist team. BACKGROUND AND PURPOSE: Treatment of periodontitis has evolved over time, with regenerative periodontal therapy at the forefront in cutting-edge periodontal care. While the techniques and materials available today are allowing therapists to push the limits of periodontal regeneration and achieve success in increasingly more difficult cases, the principles of successful regeneration remain the same. Case selection, identification and resolution of etiologic and contributing factors, proper surgical technique, follow-up and patient education are keys to obtaining a successful outcome. The impact of the dental hygienist in assessment and maintenance is highlighted. METHODS: Literature review of the key research studies evaluating the etiology and contributing factors in the development osseous defects, osseous defect and tooth-related characteristics, and principles of successful regenerative therapy. The authors draw upon their experience with patient care and clinical research to synthesize the evidence relevant to today's dental hygienist. CONCLUSIONS: Periodontal regeneration is a well-supported and predictable therapy that can be utilized to restore periodontal support and health. The dental hygienist is key in assessing and caring for the periodontal health of patients over time. Identifying who may benefit from regenerative periodontal therapy is an essential skill for today's practicing dental hygienist.

Platelet-derived growth factor promotes periodontal regeneration in localized osseous defects: 36-month extension results from a randomized, controlled, double-masked clinical trial.

BACKGROUND: Recombinant human platelet-derived growth factor (rhPDGF) is safe and effective for the treatment of periodontal defects in short-term studies up to 6 months in duration. We now provide results from a 36-month extension study of a multicenter, randomized, controlled clinical trial evaluating the effect and long-term stability of PDGF-BB treatment in patients with localized severe periodontal osseous defects. METHODS: A total of 135 participants were enrolled from six clinical centers for an extension trial. Eighty-three individuals completed the study at 36 months and were included in the analysis. The study investigated the local application of ß-tricalcium phosphate scaffold matrix with or without two different dose levels of PDGF (0.3 or 1.0 mg/mL PDGF-BB) in patients possessing one localized periodontal osseous defect. Composite analysis for clinical and radiographic evidence of treatment success was defined as percentage of cases with clinical attachment level (CAL) ≥2.7 mm and linear bone growth (LBG) ≥1.1 mm. RESULTS: The participants exceeding this composite outcome benchmark in the 0.3 mg/mL rhPDGF-BB group went from 62.2% at 12 months, 75.9% at 24 months, to 87.0% at 36 months compared with 39.5%, 48.3%, and 53.8%, respectively, in the scaffold control group at these same time points (P <0.05). Although there were no significant increases in CAL and LBG at 36 months among all groups, there were continued increases in CAL gain, LBG, and percentage bone fill over time, suggesting overall stability of the regenerative response. CONCLUSION: PDGF-BB in a synthetic scaffold matrix promotes long-term stable clinical and radiographic improvements as measured by composite outcomes for CAL gain and LBG for patients possessing localized periodontal defects ( ClinicalTrials.gov no. CT01530126).

Local minocycline as an adjunct to surgical therapy in moderate to severe, chronic periodontitis.

OBJECTIVE: The aim of the study was to evaluate the effects of minocycline microspheres on periodontal probing depth reduction when used in combination with surgery in adults with moderate to severe, chronic periodontitis. MATERIAL AND METHODS: Sixty patients with a minimum of one non-molar periodontal site > or =6 mm in two oral quadrants received either local minocycline microspheres at baseline, immediately following each of two surgical therapies (Weeks 2 and 3), and at Week 5 or surgery alone. RESULTS: The mean probing depth reduction at Week 25 at sites > or =5 mm at baseline was 2.51 mm in the test group and 2.18 mm in the control group. Smokers in the test group had a significantly greater probing depth reduction (2.30 mm) than smokers in the control group (2.05 mm). The number of sites with probing depth reductions of > or =2 and > or =3 mm were significantly higher in the test group than in the control group. CONCLUSION: Applications of local minocycline as an adjunct to surgery in adults with moderate to severe, chronic periodontitis were associated with statistically significant greater reductions in probing depth than surgery alone.

Effect of rhPDGF-BB on bone turnover during periodontal repair.

PURPOSE: Growth factors such as platelet-derived growth factor (PDGF) exert potent effects on wound healing including the regeneration of periodontia. Pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP) is a well-known biomarker of bone turnover, and as such is a potential indicator of osseous metabolic activity. The objective of this study was to evaluate the release of the ICTP into the periodontal wound fluid (WF) following periodontal reconstructive surgery using local delivery of highly purified recombinant human PDGF (rhPDGF)-BB. METHODS: Forty-seven human subjects at five treatment centres possessing chronic severe periodontal disease were monitored longitudinally for 24 weeks following PDGF regenerative surgical treatment. Severe periodontal osseous defects were divided into one of three groups and treated at the time of surgery with either: beta-tricalcium phosphate (TCP) osteoconductive scaffold alone (active control), beta-TCP+0.3 mg/ml of rhPDGF-BB, or beta-TCP+1.0 mg/ml of rhPDGF-BB. WF was harvested and analysed for local ICTP levels by radioimmunoassay. Statistical analysis was performed using analysis of variance and an area under the curve analysis (AUC). RESULTS: The 0.3 and 1.0 mg/ml PDGF-BB treatment groups demonstrated increases in the amount of ICTP released locally for up to 6 weeks. There were statistically significant differences at the week 6 time point between beta-TCP carrier alone group versus 0.3 mg/ml PDGF-BB group (p<0.05) and between beta-TCP alone versus the 1.0 mg/ml PDGF-BB-treated lesions (p<0.03). The AUC analysis revealed no statistical differences amongst groups. CONCLUSION: This study corroborates the release of ICTP as a measure of active bone turnover following local delivery of PDGF-BB to periodontal osseous defects. The amount of ICTP released from the WF revealed an early increase for all treatment groups. Data from this study suggests that when PDGF-BB is delivered to promote periodontal tissue engineering of tooth-supporting osseous defects, there is a direct effect on ICTP released from the wound.

Platelet-derived growth factor stimulates bone fill and rate of attachment level gain: results of a large multicenter randomized controlled trial.

BACKGROUND: Growth factors are generally accepted to be essential mediators of tissue repair via well-established mechanisms of action that include stimulatory effects on angiogenesis and cellular proliferation, ingrowth, differentiation, and matrix biosynthesis. The aim of this study was to evaluate in a large-scale, prospective, blinded, and randomized controlled clinical trial the safety and effectiveness of purified recombinant human platelet-derived growth factor (rhPDGF-BB) mixed with a synthetic beta-tricalcium phosphate (beta-TCP) matrix for the treatment of advanced periodontal osseous defects at 6 months of healing. METHODS: Eleven clinical centers enrolled 180 subjects, each requiring surgical treatment of a 4 mm or greater intrabony periodontal defect and meeting all inclusion and exclusion criteria. Subjects were randomized into one of three treatment groups: 1) beta-TCP + 0.3 mg/ml rhPDGF-BB in buffer; 2) beta-TCP + 1.0 mg/ml rhPDGF-BB in buffer; and 3) beta-TCP + buffer (active control). Safety data were assessed by the frequency and severity of adverse events. Effectiveness measurements included clinical attachment levels (CAL) and gingival recession (GR) measured clinically and linear bone growth (LBG) and percent bone fill (% BF) as assessed radiographically by an independent centralized radiology review center. The area under the curve (AUC), an assessment of the rate of healing, was also calculated for CAL measurements. The surgeons, clinical and radiographic evaluators, patients, and study sponsor were all masked with respect to treatment groups. RESULTS: CAL gain was significantly greater at 3 months for group 1 (rhPDGF 0.3 mg/ml) compared to group 3 (beta-TCP + buffer) (3.8 versus 3.3 mm; P = 0.032), although by 6 months, this finding was not statistically significant (P = 0.11). This early acceleration of CAL gain led to group 1 exhibiting a significantly greater rate of CAL gain between baseline and 6 months than group 3 as assessed by the AUC (68.4- versus 60.1-mm weeks; P = 0.033). rhPDGF (0.3 mg/ml)-treated sites also had significantly greater linear bone gain (2.6 versus 0.9 mm, respectively; P < 0.001) and percent defect fill (57% versus 18%, respectively; P < 0.001) than the sites receiving the bone substitute with buffer at 6 months. There was less GR at 3 months in group 1 compared to group 3 (P = 0.04); at 6 months, GR for group 1 remained unchanged, whereas there was a slight gain in gingival height for group 3 resulting in comparable GR. There were no serious adverse events attributable to any of the treatments. CONCLUSIONS: To our knowledge, this study is the largest prospective, randomized, triple-blinded, and controlled pivotal clinical trial reported to date assessing a putative periodontal regenerative and wound healing therapy. The study demonstrated that the use of rhPDGF-BB was safe and effective in the treatment of periodontal osseous defects. Treatment with rhPDGF-BB stimulated a significant increase in the rate of CAL gain, reduced gingival recession at 3 months post-surgery, and improved bone fill as compared to a beta-TCP bone substitute at 6 months.

Interdisciplinary treatment for the advanced periodontal and restorative case.

While recent advances in implant therapy have expanded options for providing care, preserving the natural dentition in an optimal state of health, function, comfort, and esthetics remains a primary goal of dentistry. For patients with moderate to advanced periodontal disease, retention of the teeth through regenerative therapy has become a predictable form of treatment for many osseous defects. Periodontal therapy, including regenerative treatment, often can enhance restorative options by retaining key abutment teeth for fixed or removable partial dentures. A case involving regenerative and resective periodontal therapy as well as fixed prostheses is described.

Factors influencing the outcome of regenerative therapy in mandibular Class II furcations: Part I.

BACKGROUND: Factors influencing the outcome of regenerative therapy of Class II furcations are incompletely and poorly understood. The purpose of this 24-month prospective study was to examine the relationship of patient-, site-, and treatment-related factors to the clinical closure of randomly selected mandibular Class II furcations. Results of therapy were evaluated at 1 and 2 years postoperatively. One-year outcome data are presented in this report. METHODS: A total of 43 otherwise healthy individuals with chronic periodontitis (26 male, 17 female), 36 to 70 years of age, completed the 12-month evaluation of the study. Entry criteria included clinical and radiographic evidence of two or more mandibular facial Class II furcation defects (> or = 3 mm horizontal probing depth). Surgical therapy was completed by four periodontists (two each) in either a university clinic or private practice. Each patient contributed two furcation defects that were treated by combination therapy using an expanded polytetrafluoroethylene (ePTFE) membrane and demineralized freeze-dried bone allograft (DFDBA). Clinical measurements included a gingival index, plaque index, mobility, and, referencing an occlusal stent, probing depth (PD), probing attachment level-vertical (PAL-V), and probing attachment level-horizontal (PAL-H). Multiple linear measurements were recorded for each site clinically and after surgical debridement to characterize defect morphology, root configuration, and barrier placement. Defect volume was computed mathematically. Postsurgical maintenance care was provided at 1 to 2, 4, 6, and 8 weeks, and then biweekly until 3 months, with subsequent supportive periodontal maintenance visits at 3-month intervals. The clinical status of the furcation (open or closed), measured by a non-treating periodontist at 1 and 2 years, was the primary outcome measure. The association of patient-related factors (e.g., smoking), site-related factors (e.g., root configuration and defect morphology), and treatment-related factors (e.g., membrane exposure) to clinical status of furcations was assessed using random effects hierarchical logistic regression analysis, controlling for design and demographic variables. Non-parametric analysis was used for specific group comparisons. RESULTS: Complete clinical closure was achieved in 74% of all sites. Of the residual furcation defects, 68% were reduced to Class I. No defects progressed to Class III. Significant improvements in mean PD and PAL-V were obtained following surgical therapy. Although the proportion of sites demonstrating complete furcation closure was comparable for smokers and non-smokers, the proportion of Class II residual defects was significantly higher among smokers than non-smokers (62.5% versus 14.3%, respectively). Increases in presurgical PAL-H were associated with monotonic decreases in the percentage of sites demonstrating complete clinical closure, with only 53% of lesions > or = 5 mm responding with complete closure. Similarly, significant reductions in the frequency of clinical closure were associated with increases in the distance between the roof of furcation and crest of bone, roof of furcation and base of defect, depth of horizontal defect, and divergence of roots at the crest of bone. CONCLUSIONS: The successful clinical closure of Class II furcations was achievable at 1 year following combination therapy with an ePTFE membrane and DFDBA. The highest frequency of clinical furcation closure was observed in early Class II defects. Furcations with vertical or horizontal bone loss of 5 mm or greater responded with the lowest frequency of complete clinical closure. Nevertheless, complete furcation closure was achievable in 50% of molars with extensive bone loss. Also, 15 out of 22 (68%) of all residual defects were reduced to Class I and only seven (8%) failed to improve, demonstrating that successful clinical resolution of advanced defects remains an attainable goal.