Periodontal healing following reconstructive surgery: effect of guided tissue regeneration using a bioresorbable barrier device when combined with autogenous bone grafting. A randomized-controlled trial 10-year follow-up

Prognostic value of a composite outcome measure for periodontal stability following periodontal regenerative treatment: A retrospective analysis at 4 years

BACKGROUND

Recently, a composite outcome measure (COM) was proposed to describe the short-term results of periodontal regenerative treatment. The present retrospective study aimed at evaluating the prognostic value of COM on clinical attachment level (CAL) change over a 4-year period of supportive periodontal care (SPC).

METHODS

Seventy-four intraosseous defects in 59 patients were evaluated at 6 months and 4 years following regenerative treatment. Based on 6-month CAL change and probing depth (PD), defects were classified as: COM1 (CAL gain ≥3 mm, PD ≤4 mm); COM2 (CAL gain <3 mm, PD ≤4 mm); COM3 (CAL gain ≥3 mm, PD >4 mm); or COM4 (CAL gain <3 mm, PD >4 mm). COM groups were compared for "stability" (i.e., CAL gain, no change in CAL or CAL loss <1 mm) at 4 years. Also, groups were compared for mean change in PD and CAL, need for surgical retreatment, and tooth survival.

RESULTS

At 4 years, the proportion of stable defects in COM1, COM2, COM3, and COM4 group was 69.2%, 75%, 50%, and 28.6%, respectively, with a substantially higher probability for a defect to show stability for COM1, COM2, and COM3 compared with COM4 (odds ratio 4.6, 9.1, and 2.4, respectively). Although higher prevalence of surgical reinterventions and lower tooth survival were observed in COM4, no significant differences were detected among COM groups.

CONCLUSIONS

COM may be of value in predicting CAL change at sites undergoing SPC following periodontal regenerative surgery. Studies on larger cohorts, however, are needed to substantiate the present findings.

Two-stage method of free gingival graft prior to periodontal regenerative surgery for the treatment of intrabony defects with insufficient keratinised tissue width: a study protocol for an open-label randomised controlled trial

INTRODUCTION

Guided tissue regeneration (GTR) combined with bone grafting for periodontal regenerative surgery has ideal clinical results for intrabony defect. However, some sites of intrabony defects often suffer from insufficient keratinised gingival width, which affects the efficacy and long-term prognosis of periodontal tissue regeneration. Free gingival graft (FGG) is an effective surgical procedure to widen the keratinised gingiva, but there are few clinical studies on FGG prior to GTR combination with bone grafting to improve clinical outcomes.

METHODS

This study is an open-label randomised controlled trial. 68 patients with periodontitis with at least one intrabony defect depth with ≥3 mm are recruited and randomly grouped. In the test group, FGG is performed first, followed by GTR and bone grafting 3 months later; while in the control group, only periodontal tissue regenerative procedures are performed. After completion of all procedures, the patients will be recalled at 3 months, 6 months and 12 months and the relevant clinical and radiographic examinations will be carried out and statistical analysis of the data will also be performed. The present research has received approval from the Ethics Committee of Shanghai Stomatological Hospital (No.2022-007) on 4 August 2022.

DISCUSSION

Exploring the effectiveness of the two-stage approach of FGG prior to periodontal tissue regenerative surgery for the treatment of keratinised gingival width deficient intrabony defects can provide a high-level evidence-based basis for the formulation of relevant treatment strategies in clinical practice.

ETHICS AND DISSEMINATION

The present research has received approval from the Ethics Committee of Shanghai Stomatological Hospital (No.2022-007) on 4 August 2022. The patients will be incorporated into this trial only after their written informed consent has been obtained. The study will be performed according to the 2013 revision of the Helsinki Declaration of 1975. Personal information of all subjects will be stored in the Department of Periodontology of Shanghai Stomatological Hospital. Data of the present research will be registered with the Clinical Trials Registry Platform. Additionally, we will disseminate the results through scientific journals.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ID: ChiCTR 2200063180. Registered on 1 September 2022.

Long-term stability of infrabony defects treated with enamel matrix derivative alone: A retrospective two-centre cohort study

AIM

To assess the long-term stability of attachment gain in infrabony defects (IBDs) 10 years after regenerative treatment with an enamel matrix derivative (EMD) alone.

MATERIALS AND METHODS

Two centres (Frankfurt [F] and Heidelberg [HD]) invited patients for re-examination 120 ± 12 months after regenerative therapy. Re-examination included clinical examination (periodontal probing depths (PPD), vertical clinical attachment level (CAL), plaque index (PlI), gingival index (GI), plaque control record, gingival bleeding index and periodontal risk assessment) and review of patient charts (number of supportive periodontal care [SPC] visits).

RESULTS

Both centres included 52 patients (29 female; median baseline age: 52.0 years; lower/upper quartile: 45.0/58.8 years; eight smokers), each contributing one IBD. Nine teeth were lost. For the remaining 43 teeth, regenerative therapy showed significant CAL gain after 1 year (3.0; 2.0/4.4 mm; p < .001) and 10 years (3.0; 1.5/4.1 mm; p < .001) during which CAL remained stable (-0.5; -1.0/1.0 mm; p = 1.000) after an average SPC of 9 years. Mixed-model regression analyses revealed a positive association of CAL gain from 1 to 10 years with CAL 12 months post operation (logistic: p = .01) as well as a higher probability for CAL loss with an increasing vertical extent of a three-walled defect component (linear: p = .008). Cox proportional hazard analysis showed a positive association between PlI after 12 months and tooth loss (p = .046).

CONCLUSION

Regenerative therapy of IBDs showed stable results over 9 years. CAL gain is associated with CAL after 12 months and decreasing initial defect depth in a three-walled defect morphology. Tooth loss is associated with PlI 12 months post operation.

CLINICAL TRIAL NUMBER

DRKS00021148 (URL: https://drks.de).

Digital photometric analysis of gingival response to periodontal treatment

OBJECTIVES

The color is a major factor in determining inflammation status in most gingival indices. Current indices have limitations mainly due to subjective nature. Digital color analysis can provide objective and accurate measurements. Thus, the present study aimed to assess by digital tool the gingival color in the different stages of an active periodontal treatment.

METHODS

Forty patients (19 males and 21 females) diagnosed with periodontitis (stage III/ IV, grade C) and treated surgically were included in the study. Clinical data (probing depth, bleeding on probing, clinical attachment level, gingival index, and gingival recession) and photographs by digital single-lens-reflex (DSLR) camera were recorded before initial periodontal treatment, which included scaling and root surface debridement (T0); the same parameters were then re-evaluated 6-8 weeks (T1) and 3 months after periodontal surgery (regenerative/resective) (T2). Differences between clinical parameters were calculated. The color space defined by the International Commission on Illumination (CIELab) was used to analyze gingival color.

RESULTS

In 56 periodontal surgical sites, 168 photographs were taken. The a*-value of the CIELab color system (higher a*- value translate to a stronger red color) was significantly reduced between T0 to T1 and further decreased at T2 (32.01, 29.28, and 27.45 respectively). Significant improvement in clinical parameters were found between T0 to T1 and T1 to T2. Sub-analysis of two distinct surgical interventions revealed that only regenerative procedure improved the a*-value, which was significantly correlated with pocket depth reduction.

CONCLUSIONS

Photometric analysis can be used to assess gingival color change during periodontal treatment of patients with periodontitis.

CLINICAL SIGNIFICANCE

Gingival inflammation is a major factor in periodontal assessment; nevertheless, all current gingival inflammation indices are partially subjective and only semi-quantitative. The digital photometric analysis may allow for accurate and objective gingival color assessment during periodontal treatment.

Tooth preservation vs. extraction and implant placement in periodontally compromised patients: A systematic review and analysis of studies

PURPOSE

The aim of this systematic review was to identify studies with a minimum of 5-years follow-up, reporting on the management of periodontally compromised teeth with either extraction and subsequent implant placement or teeth preservation with conventional periodontal treatment and application of regenerative procedures. The outcomes of these two approaches, based on clinical and radiographic data and the incidence of tooth- and implant-loss, were also investigated.

MATERIAL AND METHODS

A systematic search for studies reporting on clinical and radiographic outcomes of periodontal treatment or replacement of periodontally compromised teeth with implants was conducted in 3 electronic databases, followed by a hand-search in 8 journals. Only randomized controlled trials (RCTs), cohort studies, and case series with prospective design were included.

RESULTS

The initial search resulted in 1080 papers. After the first two screenings, 24 publications were selected for inclusion in this systematic review. The treatment protocols for the teeth preservation group contained nonsurgical and/or surgical periodontal treatment with or without regeneration procedures. The implant studies included extraction of periodontally involved teeth and implant placement with or without bone and soft tissue augmentation, followed by restoration with fixed dental prostheses (FDPs). Survival rates ranged between 81.8% and 100% in the tooth retention group, and between 94.8% and 100% in the implant group. In the extraction group, no complications were reported for 76.09% of the implants. Similarly, no complications were reported for 86.83% of the tooth retention group. The lack of standardized comparable studies prohibited conduction of a metaanalysis.

CONCLUSION

Both treatment approaches, treatment of periodontally compromised teeth, or tooth extraction followed by implant placement, present high survival rates. The application of bone regeneration techniques improves the long-term prognosis of periodontally involved teeth. Hence, treatment of periodontally involved teeth with subsequent application of a rigorous maintenance protocol can be a viable alternative for a number of years, before proceeding to extraction and replacement with dental implants. More well-designed randomized controlled trials are needed in order to draw definite conclusions on the subject.

Modified minimally invasive surgical technique in human intrabony defects with or without regenerative materials-10-year follow-up of a randomized clinical trial: Tooth retention, periodontitis recurrence, and costs

AIM

The modified minimally invasive surgical technique (M-MIST) optimizes wound stability in the treatment of intrabony defects. Short-term observations show similar results as with flap alone or adjunctive regenerative materials. This study aims to compare the stability of the long-term outcomes, complication-free survival, and costs of the three treatment options.

MATERIALS AND METHODS

Forty-five intrabony defects in 45 patients were randomized to M-MIST alone (N = 15), combined with enamel matrix derivative (M-MIST + EMD, N = 15), or EMD plus bone-mineral-derived xenograph (M-MIST + EMD + BMDX, N = 15). Supportive periodontal care (SPC) and necessary re-treatment were provided for 10 years.

RESULTS

Three subjects were lost to follow-up. Clinical attachment level differences between 1 and 10 years were -0.1 ± 0.7 mm for M-MIST, -0.1 ± 0.8 mm for M-MIST + EMD, and -0.3 ± 0.6 mm for M-MIST + EMD + BMDX (p > .05 for within- and between-group differences). Four episodes of recurrence occurred in the M-MIST group, four in the M-MIST + EMD group, and five in the M-MIST + EMD + BMDX group. No significant differences in complication-free survival were observed between the three groups (p = .47). Complication-free survival was 7.46 years (95% confidence interval: 7.05-7.87) for the whole population. The M-MIST + EMD + BMDX group lost one treated tooth. Data indicated no significant inter-group difference of the total cost of recurrence over 10 years. When the baseline cost of treatment was considered, the total cost was lower for M-MIST alone.

CONCLUSIONS

Teeth with deep pockets associated with intrabony defects can be successfully maintained over the long term with either M-MIST alone or by adding a regenerative material in the context of a careful SPC programme. M-MIST alone provided similar short- and long-term benefits as regeneration, at a lower cost. These findings need to be confirmed in larger, independent studies.

Predictability and Clinical Stability of Barrier Membranes in Treatment of Periodontal Intrabony Defects: A Systematic Review and Meta-Analysis

The adjunctive use of GTR membranes helps us to achieve predictable periodontal regeneration. The aim of this systematic review was to evaluate and compare the treatment efficacy of resorbable versus non-resorbable barrier membranes used in guided tissue regeneration in the treatment of intrabony defects in chronic periodontitis patients. The following databases were searched: Medline, the Cochrane Central Register of Controlled Trails (CENTRAL), SCOPUS, EMBASE. Randomized clinical trials (RCTs) published in English languages over the past 25 years were included. The primary outcomes assessed were: change of probing pocket depth (PD), change in clinical attachment level (CAL) and gingival recession coverage (GRC), and intrabony defect fill (IBDF). A total of eight RCTs were included for systematic review. The outcome of GR at a six-month interval revealed a significant difference in treatment effect with a mean difference of 0.42, 95% CI [0.02, 0.81]; Z = 2.09, (p = 0.04) favouring the resorbable membrane group. The intrabony defect depth fill at a 12-month interval revealed a significant difference in treatment effect with MD of 0.79, p = 0.00001; favoring the resorbable membrane group. The resorbable membrane showed a significant improvement in gingival recession coverage and intrabony defect fill, owing to its advantage of avoiding the second surgical intervention.

Ten-Year Stability of Clinical Attachment after Regenerative Treatment of Infrabony Defects and Controls

Background: A similar long-term stable clinical attachment level (CAL) of infrabony defects (IBDs) after regenerative treatment compared to control teeth would indicate a high level of stability resulting from the regenerative approach. Methods: Patients with a regeneratively treated IBD were screened 120 ± 12 months postoperatively for eligibility for study participation, and were included if complete baseline and 12-month examinations (plaque (PlI), periodontal probing depth (PPD), CAL) were available and a respective control tooth could be identified. Re-examination included clinical examination (PPD, CAL, PlI/GI, bleeding on probing, plaque control record, gingival bleeding index). Results: A total of 27 patients (16 females; age (median; lower/upper quartile): 57.0; 44.0/60.0 years; 6 smokers) contributed 27 IBDs (test), for each of which a control tooth was identified. Five test teeth (18.5%) were lost between 12 and 120 months. The remaining 22 test teeth revealed a significant CAL gain after 1 (2.5 mm; 1.0/4.0 mm, p < 0.0001) and 10 (2.5 mm; 0.5/3.5 mm, p < 0.0001) years, whereas control teeth were stable (1 year: 0.0 mm; 0.0/1.0 mm, p = 0.396; 10 years: 0.0 mm; −1.0/1.5 mm, p = 0.215). The study did not detect any significant CAL change between 1 and 10 years for test (−0.5 mm; −1.0/0.5 mm, p = 0.414) and control teeth (0.0 mm; −1.0/1.0 mm, p = 0.739). In 15 patients, test and control teeth revealed stable CAL values between 12 and 120 months. Conclusion: Regenerative treatment of IBDs exhibited stability comparable to non-surgically treated, periodontally reduced sites over a 10-year period.

Composite outcome measure (COM) and pocket closure as clinical endpoints following treatment of infra bony defects with Guided tissue regeneration and Open flap debridement

Background

Clinical outcomes of regenerative periodontal therapy has been traditionally assessed using surrogate markers, primarily clinical attachment level (CAL) gain and probing pocket depth (PPD) reduction. This study tried to assess newer clinical endpoints namely pocket closure and composite outcome measure (COM) apart from CAL gain, PPD reduction and gingival recession in patients who underwent guided tissue regeneration (GTR) and compared the same with open flap debridement (OFD) six months post treatment.

Materials and Methods

Records of 58 sites in 48 patients who had undergone GTR (28 sites) and OFD (30 sites) for infrabony defects were evaluated for CAL gain, PPD reduction, change in GR, FMBS, and FMPS at baseline and 6 months after surgery. Pocket closure and COM were used to assess the efficacy of both treatments.

Results

Statistically significant improvements were seen in both the groups except GR from baseline to 6 months. GTR-treated sites showed better improvements with a statistically significant difference in CAL gain after 6 months. Pocket closure and percentage of treatment success and failure in both the groups assessed using a COM were similar and did not differ statistically.

Conclusion

Treatment of infrabony defects with GTR combined with a xenograft offers better CAL gain after 6 months compared to OFD alone and also found that baseline PPD and FMBS were the factors determining pocket closure.

Recurrence and progression of periodontitis and methods of management in long-term care: A systematic review and meta-analysis

AIM

To systematically review the literature to evaluate the recurrence of disease of people in long-term supportive periodontal care (SPC), previously treated for periodontitis, and determine the effect of different methods of managing recurrence. The review focused on stage IV periodontitis.

MATERIALS AND METHODS

An electronic search was conducted (until May 2020) for prospective clinical trials. Tooth loss was the primary outcome.

RESULTS

Twenty-four publications were retrieved to address recurrence of disease in long-term SPC. Eight studies were included in the meta-analyses for tooth loss, and three studies for disease progression/recurrence (clinical attachment level [CAL] loss ≥2 mm). For patients in SPC of 5-20 years, prevalence of losing more than one tooth was 9.6% (95% confidence interval [CI] 5%-14%), while experiencing more than one site of CAL loss ≥2 mm was 24.8% (95% CI 11%-38%). Six studies informed on the effect of different methods of managing recurrence, with no clear evidence of superiority between methods. No data was found specifically for stage IV periodontitis.

CONCLUSIONS

A small proportion of patients with stage III/IV periodontitis will experience tooth loss in long-term SPC (tendency for greater prevalence with time). Regular SPC appears to be important for reduction of tooth loss. No superior method to manage disease recurrence was found.

Medium- and long-term clinical benefits of periodontal regenerative/reconstructive procedures in intrabony defects: Systematic review and network meta-analysis of randomized controlled clinical studies

BACKGROUND

Systematic reviews have established the short-term improvements of periodontal regenerative/reconstructive procedures compared to conventional surgical treatment in intrabony defects. However, a hierarchy of periodontal regenerative/reconstructive procedures regarding the medium- to long-term results of treatment does not exist.

AIM

To systematically assess the literature to answer the focused question "In periodontitis patients with intrabony defects, what are the medium- and long-term benefits of periodontal regenerative/reconstructive procedures compared with open flap debridement (OFD), in terms of clinical and/or radiographic outcome parameters and tooth retention?".

MATERIAL & METHODS

Randomized controlled clinical trials (RCTs), reporting on clinical and/or radiographic outcome parameters of periodontal regenerative/reconstructive procedures ≥3 years post-operatively, were systematically assessed. Clinical [residual probing pocket depth (PD) and clinical attachment level (CAL) gain, tooth loss] and radiographic [residual defect depth (RDD), bone gain (RBL)] outcome parameters were assessed. Descriptive statistics were calculated, and Bayesian random-effects network meta-analyses (NMA) were performed where possible.

RESULTS

Thirty RCTs, presenting data 3 to 20 years after treatment with grafting, GTR, EMD, as monotherapies, combinations thereof, and/or adjunctive use of blood-derived growth factor constructs or with OFD only, were included. NMA based on 21 RCTs showed that OFD was clearly the least efficacious treatment; regenerative/reconstructive treatments resulted in significantly shallower residual PD in 4 out 8 comparisons [range of mean differences (MD): -2.37 to -0.60 mm] and larger CAL gain in 6 out 8 comparisons (range of MD: 1.26 to 2.66 mm), and combination approaches appeared as the most efficacious. Tooth loss after regenerative/reconstructive treatment was less frequent (0.4%) compared to OFD (2.8%), but the evidence was sparse. There were only sparse radiographic data not allowing any relevant comparisons.

CONCLUSION

Periodontal regenerative/reconstructive therapy in intrabony defects results, in general, in shallower residual PD and larger CAL gain compared with OFD, translating in high rates of tooth survival, on a medium (3-5 years) to long-term basis (5-20 years). Combination approaches appear, in general, more efficacious compared to monotherapy in terms of shallower residual PD and larger CAL gain. A clear hierarchy could, however, not be established due to limited evidence.

Tooth survival and clinical outcomes up to 26 years after guided tissue regeneration therapy in deep intra-bony defects: Follow-up investigation of three randomized clinical trials

AIM

To investigate tooth survival and clinical long-term outcomes up to 26 years following guided tissue regeneration (GTR) therapy in deep intra-bony defects.

METHODS

Patients from three prospective clinical split-mouth studies, which investigated the outcomes of GTR therapy, were re-evaluated 21-26 years after surgery independent of the membrane type used, and tooth survival was assessed according to several site-specific and patient-related factors.

RESULTS

About 50 patients contributing 102 defects were available for this long-term follow-up. After up to 26 years (median 23.3 years), 52.9% of the teeth were still in situ. The median survival of the extracted teeth was 13.8 years. Patients with diabetes mellitus and/or smoking history lost significantly more teeth in the long term. Compared to the 1-year situation, there was no new median CAL loss after up to 26 years in the teeth which were still in situ.

CONCLUSIONS

Within the limitations of this study, our data show that more than 50% of the initially seriously diseased teeth were still in situ up to 26 years following GTR therapy despite an overall limited adherence to SPT. In the majority of these teeth, the CAL gain 1 year after GTR could be maintained over this long period.

Periodontal regeneration versus extraction and dental implant or prosthetic replacement of teeth severely compromised by attachment loss to the apex: A randomized controlled clinical trial reporting 10-year outcomes, survival analysis and mean cumulative cost of recurrence

Background

Periodontal regeneration can change tooth prognosis and represents an alternative to extraction in teeth compromised by severe intra‐bony defects. The aim of this study was to compare periodontal regeneration (PR) with tooth extraction and replacement (TER) in a population with attachment loss to or beyond the apex of the root in terms of professional, patient‐reported and economic outcomes.

Methods

This was a 10‐year randomized controlled clinical trial. 50 stage III or stage IV periodontitis subjects with a severely compromised tooth with attachment loss to or beyond the apex were randomized to PR or TER with either an implant‐ or a tooth‐supported fixed partial denture. Subjects were kept on a strict periodontal supportive care regimen every 3 months and examined yearly. Survival and recurrence analysis were performed.

Results

88% and 100% survival rates were observed in the PR and TER groups. Complication‐free survival was not significantly different: 6.7–9.1 years for PR and 7.3–9.1 years for TER (p = .788). In PR, the observed 10‐year attachment gain was 7.3 ± 2.3 mm and the residual probing depths were 3.4 ± 0.8 mm. Recurrence analysis showed that the 95% confidence interval of the costs was significantly lower for PR compared with TER throughout the whole 10‐year period. Patient‐reported outcomes and oral health‐related quality‐of‐life measurements improved in both groups.

Conclusions

Periodontal regeneration can change the prognosis of hopeless teeth and is a less costly alternative to tooth extraction and replacement. The complexity of the treatment limits widespread application to the most complex cases but provides powerful proof of principle for the benefits of PR in deep intra‐bony defect.

Dual-Functionalized Apatite Nanocomposites with Enhanced Cytocompatibility and Osteogenesis for Periodontal Bone Regeneration

The development of biomimetic bone graft materials for periodontal tissue engineering is a field of topical interest. In this study, we designed a dual-functionalized apatite nanocomposite, which could integrate multiple molecular cues for manipulating the fate of periodontal ligament stem cells (PDLSCs). Briefly, inspired by mussels, a biomimetic nanohydroxyapatite was fabricated using a polydopamine structure as a template (named as tHA) and then surface-modified with bone-forming peptide-1 (BFP-1) and vascular endothelial growth factor-mimicking peptide (QK) via a single step of catechol chemistry. Our study showed that the biofunctions of tethered peptides were not compromised on the surface of apatite nanoparticles. Because of the synergistic effect of BFP-1 and QK peptides, the dual-functionalized apatite nanocomposite showed improved cytocompatibility compared to controls. Moreover, it can boost the proliferation and osteogenic differentiation of PDLSCs, indicating excellent bioactivity of tHA-BFP/QK nanoparticles on cell fate decision. More importantly, animal experiments showed that dual-functionalized apatite nanocomposites could dramatically promote the regeneration of periodontal bone. It is concluded that our work provides an instructive insight into the design of biomimetic apatite nanocomposites, which holds a great potential for applications in periodontal bone repair.

Regenerative potential of cultured gingival fibroblasts in treatment of periodontal intrabony defects (randomized clinical and biochemical trial)

BACKGROUND

Defective cellular elements constitute an important challenge to achieve predictable periodontal regeneration. In an attempt to improve the cellularity of periodontal defects, gingival fibroblasts were implanted without their associated extracellular elements in periodontal defects to expose them to periodontal tissue mediators. In order to investigate the regenerative potential of gingival fibroblasts translocated into periodontal defects, the present study was designed to clinically and biochemically investigate the use of gingival fibroblasts (GF) and their associated mesenchymal stem cells (GMSC) in the treatment of intrabony periodontal defects.

METHODS

A total of 20 subjects were randomly divided into two groups (n = 20). Group I: ten patients were included with ten intrabony periodontal defects that received β-calcium triphosphate (β-TCP) followed by collagen membrane defect coverage, while group II: (10 patients) ten periodontal defects received cultured gingival fibroblasts (GF) on the β-TCP scaffold and covered by a collagen membrane. The clinical evaluation was carried out at the beginning and at 6 months. Gingival crevicular fluid (GCF) samples were collected directly from the test sites for the quantitative measurement of PDGF-BB and BMP-2 using the ELISA kit at 1, 7, 14, and 21 days after surgery.

RESULTS

Group II reported a significantly greater reduction in vertical pocket depth (VPD) and CAL gain compared with group I after 6 months. Radiographic bone gain was statistically higher in group II compared with group I. A significantly higher concentration of PDGF-BB was observed in group II on days 1, 3, and 7 compared with group I.

CONCLUSIONS

Translocation of gingival fibroblasts from gingival tissue to periodontal defects could be a promising option that increases cellular elements with regeneration potential. The concept of total isolation of gingival fibroblasts using occlusive membranes must be re-evaluated.

Interests of Exosomes in Bone and Periodontal Regeneration: A Systematic Review

Periodontitis is an infectious inflammatory disease characterized by clinical attachment loss and tooth supporting tissue destruction. As exosomes demonstrated pro-regenerative ability, their use in periodontal treatment has been suggested. The aim of this systematic review is to gather and summarize the most recent data regarding exosomes to determine their potential impact in bone and periodontal regeneration. Electronic databases (Pubmed, Web of Science) were searched up to February 2020. Studies assessing the impact of exosomes administration in experimental bone and periodontal defects have been identified according to PRISMA guidelines. Among the 183 identified articles, 16 met the inclusion criteria and were included in this systematic review. Experimental bone defects were mainly surgically induced with a dental bur or distraction tools. All studies considered bone healing after exosomes administration as the primary outcome. Results showed that mesenchymal stem cells derived exosomes administration promoted bone healing and neovascularization. Nevertheless, a dose-effect relationship was observed. Exosomes administration appears to promote significantly the bone healing and periodontal regeneration. However, only a limited number of studies have been carried out so far and the optimized protocols in this context need to be evaluated.

Periodontal regenerative therapy in endo-periodontal lesions: a retrospective study over 5 years

Purpose

The aim of this study was to evaluate clinical and radiographic changes and the survival rate after periodontal surgery using deproteinized bovine bone mineral (DBBM) with 10% collagen or DBBM with a collagen membrane in endo-periodontal lesions.

Methods

A total of 52 cases (41 patients) with at least 5 years of follow-up were included in this study. After scaling and root planing with or without endodontic treatment, periodontal regenerative procedures with DBBM with 10% collagen alone or DBBM with a collagen membrane were performed, yielding the DBBM + 10% collagen and DBBM + collagen membrane groups, respectively. Changes in clinical parameters including the plaque index, bleeding on probing, probing pocket depth, gingival recession, relative clinical attachment level, mobility, and radiographic bone gains were evaluated immediately before periodontal surgical procedures and at a 12-month follow-up.

Results

At the 12-month follow-up after regenerative procedures, improvements in clinical parameters and radiographic bone gains were observed in both treatment groups. The DBBM + 10% collagen group showed greater probing pocket depth reduction (4.52±1.06 mm) than the DBBM + collagen membrane group (4.04±0.82 mm). However, there were no significant differences between the groups. Additionally, the radiographic bone gain in the DBBM + 10% collagen group (5.15±1.54 mm) was comparable to that of the DBBM + collagen membrane group (5.35±1.84 mm). The 5-year survival rate of the teeth with endo-periodontal lesions after periodontal regenerative procedures was 92.31%.

Conclusions

This study showed that regenerative procedures using DBBM with 10% collagen alone improved the clinical attachment level and radiographic bone level in endo-periodontal lesions. Successful maintenance of the results after regenerative procedures in endo-periodontal lesions can be obtained by repeated oral hygiene education within strict supportive periodontal treatment.

Influence of autogenous platelet concentrate on combined GTR/graft therapy in intra-bony defects: A 13-year follow-up of a randomized controlled clinical split-mouth study

AIM

To investigate the clinical long-term outcomes 13 years following guided tissue regeneration (GTR) in deep intra-bony defects with and without additional application of autogenous platelet concentrate (APC).

METHODS

In 25 patients, two deep contra-lateral intra-bony defects were treated according to GTR using β-TCP and bio-resorbable membranes. In test defects, APC was applied additionally. After 13 years, clinical healing results were assessed and compared to results at baseline and after 1 year. Furthermore, a tooth survival analysis was carried out.

RESULTS

After 13 years, 22 patients were available for tooth survival analysis showing 81.8% of test and 86.4% of control teeth still in situ. Based on the 15 patients still available for split-mouth analysis, median CAL was 10.0 mm in test and 12.0 mm in control sites at baseline. After 1 year, both groups revealed significant CAL gains of 5.0 mm, followed by a new CAL loss of 1.0 mm in the following 12 years. There were no significant differences between test and control sites.

CONCLUSION

Within the limits of this study, the data show that most of the CAL gain following GTR can be maintained over 13 years. The additional use of APC had no positive influence on the long-term stability.

A collagen membrane containing osteogenic protein-1 facilitates bone regeneration in a rat mandibular bone defect

OBJECTIVES

Osteogenic protein-1 (OP-1) has shown osteoinductive activities and is useful for clinical treatments, including bone regeneration. Regenerative procedures using a bioabsorbable collagen membrane (BCM) are well established in periodontal and implant dentistry. We evaluated the subsequent effects of the BCM in combination with OP-1 on bone regeneration in a rat mandibular circular critical-sized bone defect in vivo.

DESIGN

We used 8 rats that received surgery in both sides of the mandible, and created the total 16 defects which were divided into 4 groups: Group 1; no treatment, as a control, Group 2; BCM alone, Group 3; BCM containing low dose 0.5μg of OP-1 (L-OP-1), and Group 4; BCM containing high dose 2.0μg of OP-1 (H-OP-1). Newly formed bone was evaluated by micro computed tomography (micro-CT) and histological analyses at 8 weeks postoperatively. In quantitative and qualitative micro-CT analyses of the volume of new bone formation, bone density, and percentage of new bone area was evaluated.

RESULTS

BCM with rhOP-1 significantly increased and accelerated bone volume, bone mineral density, and percentage of new bone area compared to control and BCM alone at 8 weeks after surgery; these enhancements in bone regeneration in the OP-1-treated groups were dose-dependent.

CONCLUSIONS

OP-1 delivered with a BCM may have effective osteoinductive potency and be a good combination for bone regeneration. The use of such a combination device for osteogenesis may result in safer and more predictable bone regenerative outcomes in the future.

Natural graft tissues and synthetic biomaterials for periodontal and alveolar bone reconstructive applications: a review

Periodontal disease is categorized by the destruction of periodontal tissues. Over the years, there have been several clinical techniques and material options that been investigated for periodontal defect repair/regeneration. The development of improved biomaterials for periodontal tissue engineering has significantly improved the available treatment options and their clinical results. Bone replacement graft materials, barrier membranes, various growth factors and combination of these have been used. The available bone tissue replacement materials commonly used include autografts, allografts, xenografts and alloplasts. These graft materials mostly function as osteogenic, osteoinductive and/or osteoconductive scaffolds. Polymers (natural and synthetic) are more widely used as a barrier material in guided tissue regeneration (GTR) and guided bone regeneration (GBR) applications. They work on the principle of epithelial cell exclusion to allow periodontal ligament and alveolar bone cells to repopulate the defect before the normally faster epithelial cells. However, in an attempt to overcome complications related to the epithelial down-growth and/or collapse of the non-rigid barrier membrane and to maintain space, clinicians commonly use a combination of membranes with hard tissue grafts. This article aims to review various available natural tissues and biomaterial based bone replacement graft and membrane options used in periodontal regeneration applications.

Clinical outcome of periodontal regenerative therapy using collagen membrane and deproteinized bovine bone mineral: a 2.5-year follow-up study

BACKGROUND

This study aimed to evaluate, longitudinally, the outcome of periodontal regenerative therapy using a deproteinized bovine bone mineral (DBBM) in combination with a collagen barrier (CB) for the treatment of intrabony defects.

RESULTS

Patients with chronic periodontitis who have completed initial periodontal therapy participated in this study. They had at least one 2- or 3-wall intrabony periodontal defect of ≥3 mm in depth. During surgery, defects were filled with DBBM and covered with CB. Ten patients completed 2.5-year reevaluation. At baseline, mean clinical attachment level (CAL) of the treated site was 8.0 mm and mean probing depth (PD) was 7.5 mm. Mean depth of intrabony component was 4.6 mm. Mean gains in CAL at 6 months and 2.5 years were 2.8 ± 1.0 and 1.4 ± 1.5 mm, respectively, both showing a significant improvement from baseline. CAL gains at 1 and 2.5 years were significantly reduced from that at 6 months. A significant improvement in PD was also noted: mean reductions in PD at 6 months and 2.5 years were 4.0 ± 0.8 and 3.2 ± 0.8 mm, respectively.

CONCLUSIONS

The combination therapy using DBBM and CB yielded statistically significant effects such as CAL gain and PD reduction, up to 2.5 years in the treatment of intrabony defects. However, the trend for decrease in CAL gain over time calls for the need for careful maintenance care.

Periodontal regeneration compared with access flap surgery in human intra-bony defects 20-year follow-up of a randomized clinical trial: tooth retention, periodontitis recurrence and costs

AIM

Compare the long-term outcomes and costs of three treatment modalities in intra-bony defects.

MATERIALS AND METHODS

Forty-five intra-bony defects in 45 patients had been randomly allocated to receive: modified papilla preservation technique with titanium-reinforced expanded-polytetrafluoroethylene (ePTFE) membranes (MPPT Tit, N = 15); access flap with expanded-PTFE membranes (Flap-ePTFE, N = 15) and access flap alone (Flap, N = 15). Supportive periodontal care (SPC) was provided monthly for 1 year, then every 3 months for 20 years. Periodontal therapy was delivered to sites showing recurrences.

RESULTS

Forty-one patients complied with SPC. Four subjects were lost to follow-up. Clinical attachment-level differences between 1 and 20 years were -0.1 ± 0.3 mm (p = 0.58) in the MPPT Tit; -0.5 ± 0.1 mm (p = 0.003) in the Flap-ePTFE and -1.7 ± 0.4 mm (p < 0.001) in the Flap. At 20 years, sites treated with Flap showed greater attachment loss compared to MPPT Tit (1.4 ± 0.4 mm; p = 0.008) and to Flap-ePTFE (1.1 ± 0.4 mm; p = 0.03). Flap group lost two treated teeth. Five episodes of recurrences occurred in the MPPT Tit, six in the Flap-ePTFE and fifteen in the Flap group. Residual pocket depth at 1-year was significantly correlated with the number of recurrences (p = 0.002). Sites treated with flap had greater OR for recurrences and higher costs of re-intervention than regenerated sites over a 20-year follow-up period with SPC.

CONCLUSIONS

Regeneration provided better long-term benefits than Flap: no tooth loss, less periodontitis progression and less expense from re-intervention over a 20-year period. These benefits need to be interpreted in the context of higher immediate costs associated with regenerative treatment. These initial observations need to be extended to larger groups and broader clinical settings.

Thirty-year stability after regeneration of a deep intrabony defect: a case report

AIMS

Report clinical improvements and 30-year stability of clinical outcomes of an intrabony defect treated with non-resorbable barriers and mucogingival surgery.

METHODS

A 18-year-old male presenting with a very severe intrabony defect at the upper right central incisor was treated with periodontal regeneration with non-resorbable barriers and a fibrin-fibronectin glue. The barriers were removed after 3 months. At 6 months, a free gingival graft (FGG) was positioned to improve mucogingival conditions. The patient was enrolled into a 6-month supportive periodontal care programme (SPC) for 30 years.

RESULTS

Clinical attachment level (CAL) of 16 mm was associated with a 12 mm osseous defect and a pocket (PD) 14 mm deep. At 1 year, a CAL of 5 mm was associated with a PD of 2 mm. The 5 mm gingival recession measured at 6 months and treated with FGG was reduced to 3 mm. Measurements taken at 10, 20 and 30 years showed a consistent creeping of the gingival margin. At 30-year examination, CAL gain was 12 mm associated with a 2 mm PD and a minimal gingival recession.

CONCLUSIONS

This case demonstrates that it is possible to treat a very severe infrabony pocket applying regeneration and mucogingival surgery and to maintain the clinical outcomes for 30 years.

Combination of Bioactive Polymeric Membranes and Stem Cells for Periodontal Regeneration: In Vitro and In Vivo Analyses

Regeneration of periodontal tissues requires a concerted effort to obtain consistent and predictable results in vivo. The aim of the present study was to test a new family of bioactive polymeric membranes in combination with stem cell therapy for periodontal regeneration. In particular, the novel polyester poly(isosorbide succinate-co-L-lactide) (PisPLLA) was compared with poly(L-lactide) (PLLA). Both polymers were combined with collagen (COL), hydroxyapatite (HA) and the growth factor bone morphogenetic protein-7 (BMP7), and their osteoinductive capacity was evaluated via in vitro and in vivo experiments. Membranes composed of PLLA/COL/HA or PisPLLA/COL/HA were able to promote periodontal regeneration and new bone formation in fenestration defects in rat jaws. According to quantitative real-time polymerase chain reaction (qRT-PCR) and Alizarin Red assays, better osteoconductive capacity and increased extracellular mineralization were observed for PLLA/COL/HA, whereas better osteoinductive properties were associated with PisPLLA/COL/HA. We concluded that membranes composed of either PisPLLA/COL/HA or PLLA/COL/HA present promising results in vitro as well as in vivo and that these materials could be potentially applied in periodontal regeneration.

A comparative clinico-radiographic study of guided tissue regeneration with bioresorbable membrane and a composite synthetic bone graft for the treatment of periodontal osseous defects

Aim:

The aim was to evaluate the bonefill in periodontal osseous defects with the help of guided tissue regeneration, bioresorbable membrane (PerioCol) + bone graft (Grabio Glascera) in combination and with bonegraft (Grabio Glascera) alone.

Materials and Methods:

The study involved total 30 sites in systemically healthy 19 patients. The parameters for evaluation includes plaque index sulcus bleeding index with one or more periodontal osseous defects having (i) probing depth (PD) of ≥ 5 mm (ii) clinical attachment loss (CAL) of ≥ 5 mm and (iii) ≥3 mm of radiographic periodontal osseous defect (iv) bonefill (v) crestal bone loss (vi) defect resolution. The study involved the three wall and two wall defects which should be either located interproximally or involving the furcation area. The statistical analysis was done using Statistical Package for Social Sciences, the Wilcoxon signed rank statistic W + for Mann–Whitney U-test.

Results:

The net gain in PD and CAL after 6 months for Group I ([PerioCol] + [Grabio Glascera]) and Group II (Grabio Glascera) was 3.94 ± 1.81 mm, 3.57 ± 2.21 mm and 3.94 ± 1.81, 3.57 ± 2.21 mm, respectively. The results of the study for Group I and Group II with regards to mean net bonefill, was 3.25 ± 2.32 (58%) mm and 5.14 ± 3.84 (40.26 ± 19.14%) mm, crestal bone loss − 0.25 ± 0.68 mm and − 0.79 ± 1.19 mm. Defect resolution 3.50 ± 2.34 mm and 5.93 ± 4.01 mm, respectively.

Conclusion:

On comparing both the groups together after 6 months of therapy, the results were equally effective for combination of graft and membrane versus bone graft alone since no statistical significant difference was seen between above parameters for both the groups. Thus, both the treatment modalities are comparable and equally effective.

Mandibular tori as bone grafts: an alternative treatment for periodontal osseous defects - clinical, radiographic and histologic morphology evaluation

OBJECTIVES

The present study was designed to evaluate the clinical, radiographic and histochemical significance of using the mandibular tori as autogenous bone graft for treatment of intraosseous defects in patients with chronic periodontitis.

MATERIALS AND METHODS

Twenty-eight sites from 14 patients with chronic periodontitis were included in this study. Each patient was treated with split mouth design; one site received torus mandibularis bone graft and the other site received a full-thickness fap alone. Histopathologic assessment was evaluated on removal of torus mandibularis to evaluate its histologic structure and by the end of the study 9 month later. Clinical and radiographic parameters were re-evaluated at 3 months interval for 1 year.

RESULTS

The results of the present study revealed significant gain in the clinical attachment level (CAL) (88.4%, 4.53 ± 0.06 mm) for torus mandibularis sites compared to (39.7%, 2.01 ± 0.04 mm) for full-thickness fap. Moreover, there was a reduction in the probing pocket depth (PPD) of (75.4%, 5.75 ± 0.12 mm) for torus mandibularis sites and (49.6%, 3.73 ± 0.14 mm) for sites treated with a full-thickness fap only; CAL and PPD differences were significant at p-value ≤0.01. Concomitantly, significant radiographic increase in the bone height and density were recorded in the test group.

CONCLUSION

The use of mandibular tori as autogenous bone graft could provide benefits as a periodontal therapeutic modality and enhance regenerative potential of periodontal intraosseous defects.

Porphyromonas gingivalis lipopolysaccharides regulate functions of bone marrow mesenchymal stem cells

OBJECTIVES

Periodontitis is one of the most widespread inflammatory diseases; it causes tooth loss and is also associated with a variety of systemic diseases. Mesenchymal stem cells (MSCs) have been used to treat periodontitis. However, it is unknown whether bacterial toxins in the periodontal environment affect MSC-mediated periodontal regeneration. Porphyromonas gingivalis lipopolysaccharides (Pg-LPS) are key toxins for development of periodontitis. The purpose of the present study was to investigate effects of P. gingivalis LPS on biological properties of MSCs.

MATERIALS AND METHODS

Mesenchymal stem cells from bone marrow (BMMSCs) were treated with different concentrations of P. gingivalis LPS (0.1-10 μg/ml), then its effects were evaluated on biological properties of BMMSCs including proliferation, apoptosis, osteogenic differentiation and capacities to inhibit activated T cells.

RESULTS

Low concentration of P. gingivalis LPS (0.1 μg/ml) accelerated MSC proliferation, osteogenic differentiation and capacities to inhibit activated T cells via up-regulation of nitric oxide. However, high concentration of P. gingivalis LPS (10 μg/ml) reduced MSC proliferation, osteogenic differentiation and capacities to inhibit activated T cells.

CONCLUSIONS

Mesenchymal stem cells were functionally different following exposure to P. gingivalis LPS at the investigated concentrations. These findings suggest that MSC-mediated periodontal regeneration may be regulated by P. gingivalis LPS.

Surgical treatment of peri-implantitis using a bone substitute with or without a resorbable membrane: a 5-year follow-up

AIM

To compare two regenerative surgical treatments for peri-implantitis over 5 years.

MATERIAL & METHODS

Twenty-five individuals with peri-implantitis remained at study endpoint. They were treated with a bone substitute and a resorbable membrane (13 individuals with 23 implants) [Group 1], or with bone substitute alone (12 individuals with 22 implants) [Group 2]. All study individuals were kept on a strict maintenance programme every third month.

RESULTS

Five-year follow-up demonstrated clinical and radiographic improvements in both groups. No implants were lost due to progression of peri-implantitis. Probing depths were reduced by 3.0 ± 2.4 mm in Group 1, and 3.3 ± 2.09 mm in Group 2 (NS). In both groups, radiographic evidence of bone gain was significant (p < 0.001). At year 5, the average defect fill was 1.3 mm (SD ± 1.4 mm) in Group 1 and 1.1 mm (SD ± 1.2 mm) in Group 2 (mean diff; 0.4 95% CI -0.3, 1.2, p = 0.24). Bleeding on probing decreased in both groups. Baseline and year 5 plaque scores did not differ between groups and was reduced from 50% to 15%.

CONCLUSION

Both procedures resulted in stable conditions. Additional use of a membrane does not improve the outcome.

Periodontal regeneration - intrabony defects: a systematic review from the AAP Regeneration Workshop

BACKGROUND

Previous systematic reviews of periodontal regeneration with bone replacement grafts and guided tissue regeneration (GTR) were defined as state of the art for clinical periodontal regeneration as of 2002.

METHODS

The purpose of this systematic review is to update those consensus reports by reviewing periodontal regeneration approaches developed for the correction of intrabony defects with the focus on patient-, tooth-, and site-centered factors, surgical approaches, surgical determinants, and biologics. This review adheres to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for systematic reviews. A computerized search of the PubMed and Cochrane databases was performed to evaluate the clinically available regenerative approaches for intrabony defects. The search included screening of original reports, review articles, and reference lists of retrieved articles and hand searches of selected journals. All searches were focused on clinically available regenerative approaches with histologic evidence of periodontal regeneration in humans published in English. For topics in which the literature is lacking, non-randomized observational and experimental animal model studies were used. Therapeutic endpoints examined included changes in clinical attachment level, changes in bone level/fill, and probing depth. For purposes of analysis, change in bone fill was used as the primary outcome measure, except in cases in which this information was not available. The SORT (Strength of Recommendation Taxonomy) grading scale was used in evaluating the body of knowledge.

RESULTS

1) Fifty-eight studies provided data on patient, tooth, and surgical-site considerations in the treatment of intrabony defects. 2) Forty-five controlled studies provided outcome analysis on the use of biologics for the treatment of intrabony defects.

CONCLUSIONS

1) Biologics (enamel matrix derivative and recombinant human platelet-derived growth factor-BB plus β-tricalcium phosphate) are generally comparable with demineralized freeze-dried bone allograft and GTR and superior to open flap debridement procedures in improving clinical parameters in the treatment of intrabony defects. 2) Histologic evidence of regeneration has been demonstrated with laser therapy; however, data are limited on clinical predictability and effectiveness. 3) Clinical outcomes appear most appreciably influenced by patient behaviors and surgical approach rather than by tooth and defect characteristics. 4) Long-term studies indicate that improvements in clinical parameters are maintainable up to 10 years, even in severely compromised teeth, consistent with a favorable/good long-term prognosis.

Long-term clinical results on the use of platelet concentrate in the treatment of intrabony periodontal defects

OBJECTIVE

The purpose of this clinical investigation was to evaluate long-term results obtained with the combination of platelet pellet (PP) plus bioabsorbable barrier membrane (BM) and to compare this outcome with the results obtained using bioactive glass (BG) graft material with a BM.

MATERIALS AND METHODS

Using a split mouth design, 11 chronic periodontitis patients (power ≥ at least 80%) were randomly assigned to treatment with a combination of PP/GTR or BG/GTR in contra-lateral dentition areas. Clinical attachment level (CAL) as the primary outcome variable, calculated as the sum of probing pocket depth (PPD) and gingival recession, and radiological alveolar bone level were recorded at baseline, 6 months and 5 years.

RESULTS

There were no statistical differences between test and control defects at baseline. PPD reductions and CAL and radiological alveolar bone height gains were statistically significant between baseline and 6 months and between baseline and 5 years in both groups (p < 0.01). Six months results of frequency distribution showed that 82% of the defects attained ≥ 4 mm CAL gain in both groups, while 5 year results showed that 73% of the defects attained 2 mm ≤ CAL gain < 4 mm in the PP/BM group and 55% of the defects attained 2 mm ≤ CAL gain < 4 mm in the BG/BM group. All parameters evaluated showed no significant differences between 6 months and 5 years in both groups (p > 0.05). No statistically significant difference in any of the clinical parameters was observed at 6 months and 5 years between the groups (p > 0.05).

CONCLUSIONS

The long-term efficacy of platelet concentrate combined with a barrier membrane is similar with the combination of bioactive glass graft material and barrier membrane, suggesting that results obtained with both treatment approaches can be maintained over a period of 5 years.

Re-stability of dental implants following treatment of peri-implantitis

It is hypothesized that active treatment of peri-implantitis (PI) leads to re-stabilization of dental implants. The aim was to assess whether or not dental implants can re-stabilize following treatment of PI. To address the focused question, MEDLINE/PubMed and Google-Scholar databases were explored from 1977 up to and including August 2013. Any disagreements between the authors were resolved via discussion. Articles published only in English were included. Hand searching was also performed. Thirteen experimental studies were included. The treatment regimes adopted in these studies comprised of antibiotic therapy, guided bone regeneration (GBR), laser therapy, use of bone matrix proteins with membrane, conventional flap surgery and mechanical debridement. In four studies, GBR promoted new bone formation; whereas two studies showed photosensitization therapy (in combination with either mechanical debridement or GBR) to regenerate bone around peri-implant defects. Six studies reported that mechanical debridement in conjunction with antibiotic therapy promoted re-stability of dental implants. In one study, recombinant human bone matrix protein-2 with a collagen membrane helped promote re-stabilization of dental implants. New bone formation may occur to some extent around dental implants following treatment for PI; however, a "complete" re-stability may be difficult to achieve without GBR.

Gore-tex(®) versus resolut adapt(®) GTR membranes with perioglas(®) in periodontal regeneration

Background:

Successful reconstruction of periodontal tissues destroyed due to periodontitis has been an evasive goal for the periodontists. Several GTR materials and bone grafts have been tried with varied success rates.

Aims and Objectives:

The aim of the present study was to evaluate and compare the efficacy of non-resorbable (GoreTex^®) and bioabsorbable (Resolut Adapt^®) membranes in combination with bioactive glass (PerioGlas^®) in the treatment of periodontal intrabony defects.

Materials and Methods:

Ten chronic periodontitis patients having bilateral matched intrabony defects were treated with non-resorbable membrane (GoreTex^®) and bioactive glass or the bioresorbable membrane (Resolut Adapt^®) and bioactive glass in split mouth design. Clinical parameters like plaque index, gingival index, probing pocket depth, clinical attachment level, and gingival recession were recorded at baseline and 9 months post-operatively. Similarly, radiographic (linear CADIA) and intra-surgical (re-entry) measurements were evaluated at baseline and 9 months post-operatively).

Results:

Both the membrane groups showed clinically and statistically significant improvement in clinical parameters i.e., reduction in probing depth (4.6 ± 1.4 mm) vs. 3.7 ± 1.3 mm) and gain in clinical attachment level (4.6 + 1.6 vs. 3.2 ± 1.5 mm) for non-resorbable and bioresorbable membrane groups, respectively. Similar trend was observed when radiographical and intra-surgical (re-entry) measurements were evaluated and compared, pre- and post-operatively at 9 months. However, on comparison between the two groups, the difference was statistically not significant.

Conclusion:

Both the barrier membranes i.e., non-resorbable (Gore-Tex^®) and bioabsorbable (Resolut Adapt^®) membranes in combination with bioactive glass (PerioGlas^®) were equally effective in enhancing the periodontal regeneration.

Effect of ozone therapy on autogenous bone graft healing in calvarial defects: a histologic and histometric study in rats

AIM

The purpose of this study was to analyze histologically the effect of ozone therapy in combination with autogenous bone graft on bone healing in rat calvaria.

METHODS

Critical size defects were created in calvaria of 27 male Wistar rats. The animals were divided into three groups of nine animals each: autogenous bone graft group (n = 9); autogenous bone graft with ozone therapy group (80%, 30 s 3 d for 2 wk, n = 9); non-treatment (control) group (n = 9). Animals were killed after 8 wk. Histomorphometric assessments, using image analysis software, and histological analyses were performed. Primary outcome was total bone area. Secondary outcomes (osteoblast number, new bone formation) were also measured.

RESULTS

Histomorphometrically, the total bone area in the autogenous bone graft with ozone therapy group (9.3 ± 2.2) were significantly higher than that of the autogenous bone graft group (5.1 ± 1.8) (p < 0.05). Also, the ozone therapy group significantly increased the percentage of total bone area compared to the autogenous bone graft group (p < 0.05). The osteoblast number significantly increased in the autogenous bone graft with the ozone therapy group (58 ± 12.3) compared to the autogenous bone graft group (9.3 ± 3.5) (p < 0.05). Also, it was observed that autogenous bone graft with ozone therapy group showed significant new bone formation when compared to the autogenous bone graft group (p < 0.05).

CONCLUSION

Ozone therapy enhances new bone formation by autogenous bone graft in the rat calvarial defect model.

Allogeneic periodontal ligament stem cell therapy for periodontitis in swine

Periodontitis is one of the most widespread infectious diseases in humans. It is the main cause of tooth loss and associated with a number of systemic diseases. Until now, there is no appropriate method for functional periodontal tissue regeneration. Here, we establish a novel approach of using allogeneic periodontal ligament stem cells (PDLSCs) sheet to curing periodontitis in a miniature pig periodontitis model. Significant periodontal tissue regeneration was achieved in both the autologous and the allogeneic PDLSCs transplantation group at 12 weeks post-PDLSCs transplantation. Based on clinical assessments, computed tomography (CT) scanning, and histological examination, there was no marked difference between the autologous and allogeneic PDLSCs transplantation groups. In addition, lack of immunological rejections in the animals that received the allogeneic PDLSCs transplantation was observed. Interestingly, we found that human PDLSCs fail to express human leukocyte antigen (HLA)-II DR and costimulatory molecules. PDLSCs were not able to elicit T-cell proliferation and inhibit T-cell proliferation when stimulated with mismatched major histocompatibility complex molecules. Furthermore, we found that prostaglandin E2 (PGE2) plays a crucial role in PDLSCs-mediated immunomodulation and periodontal tissue regeneration in vitro and in vivo. Our study demonstrated that PDLSCs possess low immunogenicity and marked immunosuppression via PGE2-induced T-cell anergy. We developed a standard technological procedure of using allogeneic PDLSCs to cure periodontitis in swine. Stem Cells 2010;28:1829–1838