Ten-year results following treatment of intra-bony defects with enamel matrix proteins and guided tissue regeneration

Reconstructive Approach in Residual Periodontal Pockets with Biofunctionalized Heterografts-A Retrospective Comparison of 12-Month Data from Three Centers

The regenerative capacity of well-preserved blood clots may be enhanced by biologics like enamel matrix derivative (EMD). This retrospective analysis compares outcomes reported by three centers using different heterografts. Center 1 (C1) treated intrabony defects combining cross-linked high-molecular-weight hyaluronic acid (xHyA) with a xenograft; center 2 (C2) used EMD with an allograft combination to graft a residual pocket. Center 3 (C3) combined xHyA with the placement of a resorbable polymer membrane for defect cover. Clinical parameters, BoP reduction, and radiographically observed defect fill at 12-month examination are reported. The 12-month evaluation yielded significant improvements in PPD and CAL at each center (p < 0.001, respectively). Analyses of Covariance revealed significant improvements in all parameters, and a significantly greater CAL gain was revealed for C2 vs. C1 (p = 0.006). Radiographic defect fill presented significantly higher scores for C2 and C3 vs. C1 (p = 0.003 and = 0.014; C2 vs. C3 p = 1.00). Gingival recession increased in C1 and C3 (p = 1.00), while C2 reported no GR after 12 months (C2:C1 p = 0.002; C2:C3 p = 0.005). BoP tendency and pocket closure rate shared similar rates. Within the limitations of the study, a data comparison indicated that xHyA showed a similar capacity to enhance the regenerative response, as known for EMD. Radiographic follow-up underlined xHyA's unique role in new attachment formation.

A Case Report of Periodontal Regenerative Therapy Using Recombinant Human Fibroblast Growth Factor 2 and Deproteinized Bovine Bone Mineral with Non-incised Papillae Surgical Approach (NIPSA) for Angular Bone Defect in Patient with Stage III Grade C Periodontitis

This report describes a case of Stage III Grade C periodontitis requiring periodontal regenerative therapy. The patient was a 19-year-old woman who presented with the chief complaint of gingival recession in the incisor region. An initial examination revealed that 45.3% of sites had a probing depth of ≥4 mm and 45.8% bleeding on probing. Radiographic examination showed angular bone resorption in #25, 26, 31, 36, and 46 and horizontal resorption in other regions. Initial periodontal therapy was implemented based on a clinical diagnosis of Stage III Grade C periodontitis (generalized aggressive periodontitis). Occlusal adjustment was also performed at sites showing premature contact (#26 and 36) after suppression of inflammation. Periodontal regenerative therapy using recombinant human fibroblast growth factor (rhFGF) -2 was performed on #25, 26, and 46. Combination therapy with rhFGF-2 and deproteinized bovine bone mineral (DBBM) was performed on #31 and 36. A non-incised papillae surgical approach (NIPSA) was used on #31. Periodontal conditions were then re-evaluated and the patient placed on supportive periodontal therapy. Regenerative therapy using rhFGF-2 and DBBM with NIPSA yielded an improvement in clinical parameters and bone resorption. This improvement has been adequately maintained over a 12-month period. Continued care is needed to maintain stable periodontal conditions.

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.

Enamel Matrix Derivative (EMD) as an Adjunct to Non-surgical Periodontal Therapy: A Systematic Review

If left untreated, periodontitis is a chronic, irreversible disease that can contribute to tooth loss. The primary objective of periodontal treatment is to arrest the progression of the disease and restore the supporting structures of the tooth. Scaling and root planing (SRP) is a common non-surgical periodontal therapy (NSPT) used to reduce inflammation, pocket depth, and clinical attachment loss. However, NSPT has limitations, notably in difficult-to-access deep pockets and molar furcations. Deep pockets (greater than 4 mm) frequently retain calculus following NSPT. To attain direct access, surgical periodontal therapy (SPT) is recommended, particularly for pockets deeper than 5 mm. Enamel matrix derivative (EMD) has emerged in recent years as a tool for periodontal regeneration when used in conjunction with NSP for infrabony defects. EMD may also have advantageous effects when combined with NSPT. The purpose of this review is to provide a thorough understanding of the effects of EMD as an adjunct to NSPT. The databases Scopus, PubMed/MEDLINE, Google Scholar, Cochrane, and Embase were systematically searched to identify relevant studies on the benefits of EMD and its use as an adjunct to NSPT. Incorporating EMD into NSPT reduces chair time, and 60% of studies demonstrated considerable benefits compared to SRP alone, according to the findings. On the basis of research, it can be concluded that EMD can be used as an adjunct to NSPT, thereby reducing the amount of time spent in the operating chair. In some cases, it can, therefore, be regarded as an alternative to surgical treatment.

Affinity-selected heparan sulfate collagen device promotes periodontal regeneration in an intrabony defect model in Macaca fascicularis

It is challenging to regenerate periodontal tissues fully. We have previously reported a heparan sulfate variant with enhanced affinity for bone morphogenetic protein-2, termed HS3, that enhanced periodontal tissue regeneration in a rodent model. Here we seek to transition this work closer to the clinic and investigate the efficacy of the combination HS3 collagen device in a non-human primate (NHP) periodontitis model. Wire-induced periodontitis was generated in ten Macaca fascicularis, and defects were treated with Emdogain or collagen (CollaPlug) loaded with (1) distilled water, (2) HS low (36 µg of HS3), or (3) HS high (180 µg of HS3) for 3 months. At the endpoint, microscopic assessment showed significantly less epithelial down-growth, greater alveolar bone filling, and enhanced cementum and periodontal ligament regeneration following treatment with the HS-collagen combination devices. When evaluated using a periodontal regeneration assessment score (PRAS) on a scale of 0-16, collagen scored 6.78 (± 2.64), Emdogain scored 10.50 (± 1.73) and HS low scored 10.40 (± 1.82). Notably, treatment with HS high scored 12.27 (± 2.20), while healthy control scored 14.80 (± 1.15). This study highlights the efficacy of an HS-collagen device for periodontal regeneration in a clinically relevant NHP periodontitis model and warrants its application in clinical trials.

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).

The endodontic-periodontal juncture: Where two worlds meet. An overview of endo-perio lesions

Endodontic and periodontal infections can be difficult to differentiate from one another and often share common clinical features making diagnosis challenging. The aim of this review is to discuss endodontic and periodontal infections in situations where they occur concurrently, or where one influences the other. The available literature investigating endodontic and periodontal infections was examined for contemporary knowledge regarding endodontic-periodontal interactions. Strategies to facilitate diagnosis and treatment planning are discussed. When endodontic and periodontal infections occur together, or signs and symptoms are similar, diagnosis can be challenging. Determining the primary source of infection is imperative to ensure appropriate treatment planning. The pulp and periodontal tissues are intimately related, with many possible pathways for infection from one to the other. Diagnosis of the primary source of the infection can be difficult and sometimes an inter-disciplinary approach to treatment is required. © 2023 Australian Dental Association.

Biomimetic Approaches in Clinical Endodontics

In the last few decades, biomimetic concepts have been widely adopted in various biomedical fields, including clinical dentistry. Endodontics is an important sub-branch of dentistry which deals with the different conditions of pulp to prevent tooth loss. Traditionally, common procedures, namely pulp capping, root canal treatment, apexification, and apexigonesis, have been considered for the treatment of different pulp conditions using selected materials. However, clinically to regenerate dental pulp, tissue engineering has been advocated as a feasible approach. Currently, new trends are emerging in terms of regenerative endodontics which have led to the replacement of diseased and non-vital teeth into the functional and healthy dentine-pulp complex. Root- canal therapy is the standard management option when dental pulp is damaged irreversibly. This treatment modality involves soft-tissue removal and then filling that gap through the obturation technique with a synthetic material. The formation of tubular dentine and pulp-like tissue formation occurs when stem cells are transplanted into the root canal with an appropriate scaffold material. To sum up tissue engineering approach includes three components: (1) scaffold, (2) differentiation, growth, and factors, and (3) the recruitment of stem cells within the pulp or from the periapical region. The aim of this paper is to thoroughly review and discuss various pulp-regenerative approaches and materials used in regenerative endodontics which may highlight the current trends and future research prospects in this particular area.

Efficacy of biologics for the treatment of periodontal infrabony defects: An American Academy of Periodontology best evidence systematic review and network meta-analysis

BACKGROUND

A large variety of biomaterials, biologics and membranes have been utilized in the past 40 years for the regenerative treatment of periodontal infrabony defects. Biologic agents have progressively gained popularity among clinicians and are routinely used for periodontal regeneration. In alignment with the goals of the American Academy of Periodontology (AAP) Best Evidence Consensus (BEC) on the use of biologic mediators in contemporary clinical practice, the aim of this sytematic review was to evaluate the effect of biologic agents, specifically autogenous blood-dervied products (ABPs), enamel matrix derivative (EMD) and recombinant human platelet-derived growth factor-BB (rhPDGF-BB), on the regenerative outcomes of infrabony defects.

METHODS

A detailed systematic search was conducted to identify eligible randomized control trials (RCTs) reporting the outcomes of periodontal regenerative therapy using biologics for the treatment of infrabony defects. A frequentist mixed-modeling approach to network meta-analysis (NMA), characterized by the assessment of three individual components for the treatment of an infrabony defect (the bone graft material [BG], the biologic agent, the application of a barrier membrane) was performed to evaluate and compare the relative efficacy of the different components, on the outcomes of different therapeutic modalities of periodontal regeneration.

RESULTS

A total of 153 eligible RCTs were included, with 150 studies contributing to the NMA. The quantitative analysis showed that the addition of biologic agents to bone graft significantly improves the clinical and radiographic outcomes, as compared to BG and flap procedures alone. Barrier membranes enhanced the regenerative outcomes of BG but did not provide further benefits in combination with biologics. The type of BG (autogenous, allogeneic, xenogeneic or alloplastic) and the biologic agent (EMD, platelet-rich fibrin [PRF], platelet-rich plasma [PRP] or rhPDGF-BB) played a significant role on the final outcomes of infrabony defects. Allogeneic and xenogeneic BGs exhibited statistically significantly superior clinical gain than synthetic and autogenous BGs (p < 0.05 in all the comparisons), while rhPDGF-BB and PRF demonstrated significantly higher stability of the gingival margin (p < 0.01) and radiographic bone fill/gain (p < 0.05), together with greater, although not statistically significant, clinical attachment level gain and pocket depth reduction, than EMD and PRP. Overall, rhPDGF-BB exhibited the largest effect size for most parameters, including clinical attachment level gain, pocket depth reduction, less gingival recession and radiographic linear bone gain. Considering the relatively high number of trials presenting an unclear or high risk of bias, the strength of recommendation supporting the use of PRP was judged weak, while the recommendation for EMD, PRF and rhPDGF-BB was deemed in favor.

CONCLUSIONS

Biologics enhance the outcomes of periodontal regenerative therapy. Combination therapies involving BGs + biologics or BGs + barrier membrane demonstrated to be superior to monotherapies. The choice of the type of BG and biologic agent seems to have significant impact on the clinical and radiographic outcomes of infrabony defects.

Prognostic factors affecting periodontal regenerative therapy using recombinant human fibroblast growth factor-2: A 3-year cohort study

Introduction

Fibroblast growth factor-2 (FGF-2) has been reported to promote periodontal tissue regeneration. However, no study has investigated the long-term prognosis of periodontal regenerative therapy using FGF-2 to date. The aim of this study was to observe the long-term outcomes as well as to investigate the factors affecting the prognosis of periodontal regenerative therapy using FGF-2.

Methods

Sixty intrabony defects were prospectively investigated for three years after periodontal regenerative therapy with recombinant human FGF-2 (rhFGF-2) by evaluating probing pocket depth (PPD) and radiographic bone defect depth (RBD). The factors influencing RBD were assessed by conducting a multivariate linear regression analysis after adjusting for confounders.

Results

The mean age of the participants was 62.4 ± 13.4 years, and baseline PPD and RBD were 6.1 ± 1.9 mm and 4.5 ± 1.8 mm, respectively. At six months, one year, and three years after surgery, PPD and RBD had significantly improved to 4.2 ± 1.7, 3.7 ± 1.4, 4.0 ± 1.9 mm and to 3.08 ± 2.05, 2.73 ± 1.90, 2.51 ± 2.15 mm, respectively. At the three-year examination, a significant positive association was deteced between RBD reduction and RBD at baseline, while the association was not significant between RBD reduction and the radiographic bony angle, number of bony walls of the defect, or the furcation involvement at baseline.

Conclusions

rhFGF-2 was effective for alveolar bone regeneration in patients with periodontitis and maintained the improved parameters over the three-year observation period. The radiographic bone defect depth at baseline was found to be the factor affecting the periodontal regenerative therapy using rhFGF-2 in the intrabony defects.

Trial registration number

UMIN000027979.

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Mid-term observation following periodontal regenerative therapy using rhFGF-2.

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Reductions in PPD and radiographic defect depth were maintained for 3 years.

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Evaluation of prognostic factors of rhFGF-2 application in intrabony defects.

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Preoperative radiographic defect depth predicts postoperative bone fill.

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.

Periodontal granulation tissue preservation in surgical periodontal disease treatment: a pilot prospective cohort study

Purpose

Methods

Results

Conclusions

The Evolution of Surgical Techniques and Biomaterials for Periodontal Regeneration

The understanding of biological concepts in wound healing together with the evolution in biomaterials applied in periodontal regeneration allowed for improved, minimally invasive surgical techniques with a wider range of application and adapted to achieve multiple goals at the same time. Regenerating attachment was never the sole end point, but maintaining the patient's own natural dentition in health and esthetics is becoming a feasible goal even in cases considered challenging just a few years ago. In this article we report on the evolution of techniques and biomaterials and their application in esthetic and challenging cases.

Efficacy of a new-generation platelet-rich fibrin in the treatment of periodontal intrabony defects: a randomized clinical trial

Background

The aim of the study was to clinically evaluate the healing of intrabony defects after treatment with a new generation of platelet-rich fibrin (A-PRF+) respect to enamel matrix derivative (EMD).

Methods

Thirty (30) intrabony defects of 18 patients (9 males, 9 females) were randomly treated with A-PRF+ (test, n = 15) or EMD (control, n = 15). The following clinical parameters were recorded at baseline and 6 months after surgery: pocket depth (PD), gingival recession (GR) and clinical attachment level (CAL). After debridement the intrabony defects were filled with A-PRF+ in the test group, respectively with EMD in the control group, and fixed with sutures to ensure wound closure and stability.

Results

Both treatment methods resulted in statistically significant PD reductions, respectively CAL gains six months post-operatively. No statistically significant differences were found between the two groups as the mean CAL gain was 2.33 ± 1.58 mm in the A-PRF+ group, respectively 2.60 ± 1.18 mm in the EMD group (p < 0.001).

Conclusion

Within the limits of this study the new-generation platelet-rich fibrin seems to be as clinically effective as EMD during surgical treatment of intrabony defects. Treatment with A-PRF+ or EMD resulted in reliable clinical outcomes. The use of A-PRF+ as a human autologous product can give a positive impact on periodontal healing.

Clinical Relevance A-PRF+ may be suitable for the treatment of intrabony periodontal defects.

Trial registration number (TRN) NCT04404374 (ClinicalTrials.gov ID).

Treatment of Intrabony Defects with a Combination of Hyaluronic Acid and Deproteinized Porcine Bone Mineral

Background: this study evaluates the clinical outcomes of a novel approach in treating deep intrabony defects utilizing papilla preservation techniques with a combination of hyaluronic acid (HA) and deproteinized porcine bone mineral. Methods: 23 patients with 27 intrabony defects were treated with a combination of HA and deproteinized porcine bone mineral. Clinical attachment level (CAL), pocket probing depth (PPD), gingival recession (REC) were recorded at baseline and 6 months after the surgery. Results: At 6 months, there was a significant CAL gain of 3.65 ± 1.67 mm (p < 0.001) with a PPD reduction of 4.54 ± 1.65 mm (p < 0.001), which was associated with an increase in gingival recession (0.89 ± 0.59 mm, p < 0.001). The percentage of pocket resolution based on a PPD ≤4 mm was 92.6% and the failure rate based on a PPD of 5 mm was 7.4%. Conclusions: the present findings indicate that applying a combined HA and xenograft approach in deep intrabony defects provides clinically relevant CAL gains and PPD reductions compared to baseline values and is a valid new approach in treating intrabony defects.

Treatment of intrabony periodontal defects in controlled diabetic patients with an enamel matrix derivative: a split-mouth randomized clinical trial

OBJECTIVE

This split-mouth randomized controlled trial aimed to evaluate the effect of enamel matrix derivative (EMD) associated with a simplified papilla preservation flap (SPPF) compared to SPPF alone in the surgical treatment of intrabony defects (ID) in type 2 diabetic mellitus (T2DM) patients.

MATERIAL AND METHODS

Thirteen patients with controlled T2DM presenting with ID in at least two quadrants were included. In each patient, the test site (TS) was treated with SPPF plus EMD, whereas the control site (CS) was treated only with SPPF. Prior to surgery and at 6 months after intervention, the following parameters were evaluated: clinical attachment level (CAL), probing pocket depth (PPD), and gingival recession (GR).

RESULTS

The TS and CS demonstrated a mean CAL gain of 3.31 ± 0.96 mm and 1.61 ± 1.12 mm, and a PPD reduction from 8.15 ± 0.98 to 3.00 ± 0.57 mm and 7.53 ± 0.96 to 4.69 ± 0.63 mm after 6 months, respectively. In both sites, the mean CAL gain and PPD reduction improved significantly after 6 months compared to baseline; however, the improvement was higher in the TS (p < 0.001).

CONCLUSIONS

Both surgical procedures presented with clinical improvements in controlled T2DM patients. However, the additional use of EMD showed enhanced clinical results after 6 months with regard to CAL gain and PPD reduction.

CLINICAL RELEVANCE

This study showed a better PPD reduction and CAL gain when an EMD was applied in addition to SPPF. Therefore, EMD may be used to enhance clinical outcomes in periodontal ID of controlled T2DM patients.

Clinical Pilot Series of Non-Self-Contained Periodontal Infrabony Defects Treated with a Slowly Resorbable Bovine Pericardium Membrane in Combination with Low-Temperature-Treated Decellularized Bovine Bone Particles

The aim of this case series was to present the clinical outcomes of non-contained intrabony periodontal defects (IPDs) treated by means of papillary preservation flaps in association with a slowly resorbable bovine pericardium membrane (BPM) and a low-temperature-treated bovine bone graft (BBG). Eight healthy, non-smoking patients (two males and six females, mean age 48 ± 8 years) with stage 3 periodontitis and at least one site with residual probing depth (PD) ≥ 6 mm associated with a non-contained IPD ≥ 3 mm were treated. Two weeks after surgery, no adverse events were observed, and an early wound healing score (EHS) of 8.1 ± 1.0 was recorded. After 1 year, the mean probing depth (PD) reduction and mean clinical attachment level gain (CAL-gain) accounted for 4.8 ± 0.7 and 3.5 ± 0.7 mm, respectively, whereas the mean gingival recession (REC) was of 1.2 ± 0.3 mm. Radiographic bone fill was observed in all cases. In conclusion, the treatment of non-contained IPDs with a slowly resorbable BPM and a low-temperature-treated BBG could be considered safe and may result in significant clinical improvements 1 year after surgery.

Second Attempt of Guided Tissue Regeneration on a Previous Successfully Grafted Site with Periodontal Breakdown-A 5-Year Follow-up

Guided tissue regeneration (GTR) has been proven to promote attachment and regeneration of periodontal tissue. However, there is a 20 to 40% incidence of attachment loss on regenerated attachments reported in the literature. To my knowledge, this is the first case report on a second attempt in GTR on a previous successful grafted site with clinical attachment loss. A healthy 17-year-old Chinese male patient had GTR performed with xenograft particles and bovine resorbable membrane on his root-canal treated, fused upper right lateral incisor and upper right canine (#12-#13) in 2007. Probing depth on the mid-palatal region of #12-#13 was reduced to 4 mm and maintained for the next 4 years. But in the fifth year, probing depth increased to 11 mm with no endodontic symptoms, and a second attempt of GTR using the same materials was carried out. The probing depth at the surgical site was reduced to 4 mm and successfully maintained for another 5 years. Irregular maintenance and the presence of plaque retentive factor could have caused the clinical attachment loss on #12-#13. This case shows it is possible to attempt GTR on a previous successfully grafted site. GTR did not increase tissue resistance against periodontal breakdown. Hence, proper maintenance planning for GTR sites is important to prevent periodontal breakdown.

Long-term clinical outcomes of periodontal regeneration with Enamel Matrix Derivative (EMD): a retrospective cohort study with a mean follow-up of 10 years

BACKGROUND

Despite the large body of evidence on the efficacy of Enamel Matrix Derivative (EMD) in the treatment of periodontal intrabony defects, few studies reported long-term data (≥ 10-year).

METHODS

Periodontal patients treated with regenerative surgery with EMD between 1999 and 2012 were invited to participate in a clinical examination. The following clinical parameters were recorded and compared at baseline (T0), 6 months after surgery (T1) and after at least 8 years of follow-up (T2): probing depth (PD), gingival recession (GR), clinical attachment level (CAL), plaque and bleeding scores. The primary outcome variable was CAL change.

RESULTS

Forty-one patients with 75 treated teeth were available for analysis. Out of these, 68 (tooth survival rate: 90.7%) reached the latest follow-up with a mean observation period of 10.3 years (range: 8.0-21.3). The most frequent reason for tooth loss was recurrence of periodontal disease. Tooth survival curves showed a statistically significant difference between smokers and non-smokers (p = 0.028). Mean CAL changed from 8.43 ± 1.86 (T0) to 6.47 ± 1.70 (T1) (p<0.001) and to 5.91 ± 1.83 (T2) (p<0.001). At T1, a CAL gain of ≥3 mm was measured in 35% of the defects while at T2 it was detected in 51% of cases.

CONCLUSIONS

Within their limitations, the present results have shown that in intrabony defects, the clinical improvements obtained following regenerative surgery with EMD can be maintained on a mean period of 10 years. Smoking status and maxillary molars were correlated with an increased risk for tooth and CAL loss, respectively. This article is protected by copyright. All rights reserved.

Electrospun core-shell nanofibers with encapsulated enamel matrix derivative for guided periodontal tissue regeneration

The osteogenic effect of a composite electrospun core-shell nanofiber membrane encapsulated with Emdogain^® (EMD) was evaluated. The membrane was developed through coaxial electrospinning using polycaprolactone as the shell and polyethylene glycol as the core. The effects of the membrane on the osteogenic differentiation of periodontal ligament stem cells (PDLSCs) were examined using Alizarin Red S staining and qRT-PCR. Characterization of the nanofiber membrane demonstrated core-shell morphology with a mean diameter of ~1 µm. Examination of the release of fluorescein isothiocyanate-conjugated bovine serum albumin (FITC-BSA) from core-shell nanofibers over a 22-day period showed improved release profile of encapsulated proteins as compared to solid nanofibers. When cultured on EMD-containing core-shell nanofibers, PDLSCs showed significantly improved osteogenic differentiation with increased Alizarin Red S staining and enhanced osteogenic gene expression, namely OCN, RUNX2, ALP, and OPN. Core-shell nanofiber membranes may improve outcomes in periodontal regenerative therapy through simultaneous mechanical barrier and controlled drug delivery function.

Non-Incised Papilla Surgical Approach and Leukocyte Platelet-Rich Fibrin in Periodontal Reconstruction of Deep Intrabony Defects: A Case Series

We present the preliminary results of the treatment of teeth with a deep, non-contained periodontal residual defect, vestibular bone dehiscence, and soft tissue recession, by combining an apical non-incised papilla surgical approach (NIPSA) to the defect and leukocyte platelet-rich fibrin (L-PRF) in the vestibular aspect. Four patients (upper left first premolar, upper left central incisor, upper right central incisor and upper right lateral incisor) have been treated. At one year of follow up, all cases showed a considerable reduction in the periodontal pocket depth, a gain in clinical attachment and no bleeding on probing, as well as an improvement in the marginal soft tissue minimizing soft tissue contraction (recession and/or loss of papilla) and improving soft tissue architecture. NIPSA plus L-PRF seem to improve clinical outcomes in deep non-contained intrabony defects associated with soft tissue recession.

Healing of intrabony defects following regenerative surgery by means of single-flap approach in conjunction with either hyaluronic acid or an enamel matrix derivative: a 24-month randomized controlled clinical trial

Objectives

The aim of this randomized controlled clinical trial was to compare the clinical outcomes obtained in intrabony defects following regenerative periodontal surgery using the single-flap approach (SFA) in conjunction with either hyaluronic acid (HA) or enamel matrix derivative (EMD).

Materials and methods

Thirty-two intrabony defects in 32 healthy subjects were randomly assigned: HA (test group) or EMD (control group). Clinical attachment level (CAL), probing depth (PD), gingival recession (REC), and bleeding on probing (BOP) were recorded at baseline,12, 18, and 24 months after surgery.

Results

At 24 months, both treatments resulted in statistically significant clinical improvements evidenced by PD-reduction and CAL-gain (p<0.001). The mean CAL-gain was 2.19±1.11 mm in the test and 2.94±1.12 mm in the control sites (p=0.067). PD-reduction was statistically significantly higher for the control group (4.5±0.97 mm) than the test group (3.31±0.70 mm), (p=0.001). CAL-gain ≤ 3 mm was observed in 87.5% and in 62.5% of the test and control sites, respectively. Test sites showed slightly lower REC values than the control sites. No statistically significant differences were found for BOP between treatments.

Conclusions

The present findings indicate that both treatments led to statistically significant clinical improvements compared to baseline, although the application of EMD resulted in statistically significantly higher PD-reduction compared to the use of HA.

Clinical relevance

The use of HA in conjunction with a SFA resulted in significant PD-reduction and CAL-gain, pointing to the potential clinical relevance of this material in regenerative periodontal surgery.

Combined application of geranylgeranylacetone and amelogenin promotes angiogenesis and wound healing in human periodontal ligament cells

Amelogenin directly binds to glucose-regulated protein 78 (Grp78). Cell migration activity is expected to increase when human periodontal ligament cells (hPDLCs) overexpressing Grp78 are treated with amelogenin. Geranylgeranylacetone (GGA) is a drug that induces the expression of heat shock protein and is routinely used to treat gastric ulcers. Here, we investigated the changes in the properties and behavior of hPDLCs in response to treatment with GGA and the synergistic effects of amelogenin stimulation in hPDLCs pretreated with GGA for the establishment of a novel periodontal tissue regenerative therapy. We observed that GGA treatment increased Grp78 protein expression in hPDLCs and enhanced cell migration. Microarray analysis demonstrated that increased Grp78 expression triggered the production of angiopoietin-like 4 and amphiregulin, which are involved in the enhancement of angiogenesis and subsequent wound healing via the activation of hypoxia-inducible factor 1α and peroxisome proliferator-activated receptors as well as the phosphorylation of cAMP response element-binding protein and protein kinase A. Moreover, the addition of recombinant murine amelogenin (rM180) further accelerated hPDLC migration and tube formation of human umbilical vein endothelial cells due to the upregulation of interleukin-8 (IL-8), monocyte chemotactic protein 1, and IL-6, which are also known as angiogenesis-inducing factors. These findings suggest that the application of GGA to gingival tissue and alveolar bone damaged by periodontal disease would facilitate the wound healing process by inducing periodontal ligament cells to migrate to the root surface and release cytokines involved in tissue repair. Additionally, supplementation with amelogenin synergistically enhanced the migratory capacity of these cells while actively promoting angiogenesis. Therefore, the combined application of GGA and amelogenin may establish a suitable environment for periodontal wound healing and further drive the development of novel therapeutics for periodontal tissue regeneration.

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.

Minimally Invasive Surgical Strategies in Regenerative/Reconstructive Periodontal Therapy

FOCUSED CLINICAL QUESTION

After a quick overview on the original principles of guided periodontal regeneration (GTR), the aim of this paper focuses on the advantages of minimally invasive surgical techniques for periodontal regeneration/reconstruction. The specific clinical question to answer is: Are there new clinical parameters useful to choose the best minimal invasive surgery approach for each periodontal defect? An update of the decision trees is to propose after highlighting some clinical parameters deemed relevant for the choice of the most suitable minimally invasive surgical approach and which therefore are considered by us having a place in the new decision trees.

SUMMARY

Starting from the paper of Evian dated 1985 until that of Aslan in 2017, we have analyzed the minimal periodontal surgical techniques proposed for the periodontal regeneration. In addition to the parameters set in the various flowcharts, we have highlighted the following additional parameters: papilla height loss; supra bone component of the defect; Δ Bone Sounding; width of keratinized tissue.

CONCLUSION

The decision-making chart improved with the new clinically relevant factors may serve as a useful guideline for dentists, but to definitively validate it, further studies need to be developed in the future. In order to clarify the proposed flow chart, the authors present two different clinical cases.

GTR Treatment in Furcation Grade II Periodontal Defects with the Recently Reintroduced Guidor PLA Matrix Barrier: A Case Series with Chronological Step-by-Step Illustrations

Molars with a furcation involvement (FI) exceeding grade 1 according to Hamp's classification are at approximately doubled risk of tooth loss. Guided tissue regeneration (GTR) is a regenerative approach in the treatment of periodontal defects and is aimed at achieving new clinical attachment formation. The aim of this case series was to assess the efficacy of a newly reintroduced polylactic acid (PLA) matrix barrier and to evaluate the feasibility of the surgical approach. 11 patients with an average age of 58.7 years were treated with GTR using a PLA matrix barrier. Patients were instructed not to brush and chew on the treated side for 4 weeks. A gentle clinical probing was performed after 6 months for the first time after surgery. The patients were included into individual maintenance program at three months' interval. The clinical improvement was expressed by reduced horizontal penetration of the probe accompanied by vast resolution of the vertical defect component. The change from grade II to grade I or complete resolution of the FI could be seen in 8 from 11 sites included. The newly reintroduced PLA matrix barrier showed promising results after a 12-month observation period with clinical attachment gain.

Modified minimally invasive surgical technique plus Bio-Oss Collagen for regenerative therapy of isolated interdental intrabony defects: study protocol for a randomised controlled trial

INTRODUCTION

Periodontal regeneration surgery has been widely used to deal with intrabony defects. Modified minimally invasive surgical technique (M-MIST) is designed to deal with isolated interdental intrabony defects, and has achieved satisfactory periodontal regenerative effect. Bio-Oss Collagen, as a bioactive material, has been applied for periodontal regeneration. It is similar to human cancellous bone, with the ability to promote bone formation; furthermore, it has exceptional plasticity and spatial stability. The combination of different materials and techniques has become a research hotspot in recent years. By combining the superiority of regeneration technology and materials, better regenerative effect can be achieved. This study will search for differences between M-MIST combined with Bio-Oss Collagen, and M-MIST alone in regeneration therapy for intrabony defects.

METHODS AND ANALYSIS

The present research is designed as a two-group parallel randomised controlled trial. The total number of patients is 40. The patients will be randomly assigned to two groups, with 20 participants in each group, for further periodontal regenerative surgery. Test group: M-MIST plus Bio-Oss Collagen.

CONTROL GROUP

M-MIST. After 12 months, the measurement indices will be recorded; these will include clinical attachment gain and radiographical intrabony defect depth change as the primary results, and secondary outcomes of full-mouth plaque scores, probing depth, full-mouth bleeding scores, gingival recession, mobility, gingival papilla height and Visual Analogue Scale. The paired samples t-test will be applied to detect any difference between baseline and 1-year registrations. A general linear model will be performed to study the relationship between the secondary and the primary outcome.

ETHICS AND DISSEMINATION

The present research has received approval from the Ethics Committee of Peking University School and Hospital of Stomatology (PKUSSIRB-202053002). Data of the present research will be registered with the International Clinical Trials Registry Platform. Additionally, we will disseminate the results through scientific dental journals.

TRIAL REGISTRATION NUMBER

ChiCTR-2000030851.

PROTOCOL VERSION

Protocol Version 4, 14 July 2020.

Effect of systemic antibiotics on the outcomes of regenerative periodontal surgery in intrabony defects: a randomized, controlled, clinical study

OBJECTIVES

To assess the potential influence of systemic antibiotic administration on the healing of periodontal intrabony defects treated with deproteinized bovine bone mineral (DBBM) and collagen membrane.

MATERIALS AND METHODS

Forty-one intrabony defects were treated by means of DBBM and collagen membrane (GTR). Postoperatively, the patients received either systemic antibiotics (i.e., 1 g of amoxicillin, twice daily for 7 days) (test) or no antibiotics (control). Clinical attachment level (CAL), probing depth (PD), and gingival recession (GR) were measured at baseline and at 1 year following regenerative surgery. The depth of the intrabony component (INTRA DD) and its width (INTRA DW) were measured during surgery and after 1 year at reentry. The depth (RxD) and width (RxW) of the intrabony defects were evaluated radiographically at baseline and at 1 year.

RESULTS

No adverse events were observed in any of the two groups throughout the entire study period. In the test group, mean CAL changed from 8.7 ± 1.4 mm at baseline to 5.0 ± 1.7 mm at 1 year (p < 0.0001), while PD decreased from 7.8 ± 1.5 mm at baseline to 4.0 ± 0.9 mm at 1 year (p < 0.0001). In the control group, mean CAL changed from 8.6 ± 1.9 mm to 5.9 ± 1.6 mm (p < 0.001) and mean PD improved from 7.4 ± 1.3 mm to 4.1 ± 1.3 mm (p < 0.001). Mean CAL gain measured 3.6 ± 1.6 mm in the test and 2.7 ± 1.6 mm in the control group, respectively. Defect fill (i.e., INTRA DD gain) at re-entry measured 3.7 ± 1.8 mm in the test and 2.7 ± 2.1 mm in the control group. A CAL gain of ≥ 3 mm was measured in 76% of the defects in the test group and in 40% of the defects in the control group, respectively. In both groups, all evaluated clinical and radiographic parameters improved statistically significantly compared with baseline, but no statistically significant differences were found between the two groups.

CONCLUSIONS

Within their limits, the present study has failed to show any substantial added clinical benefits following the postoperative administration of amoxicillin in conjunction with regenerative periodontal surgery using DBBM and GTR.

CLINICAL RELEVANCE

The post-surgically administration of systemic antibiotics does not seem to be necessary following regenerative periodontal surgery.

A long-term treatment outcome of intentional replantation in Taiwanese population

BACKGROUND/PURPOSE

Intentional replantation was a conventional treatment option in surgical endodontics but usually be seen as a last resort. Therefore, the purpose of this study was to evaluate the long-term treatment outcome of intentional replantation in Taiwanese population, including the survival rates and the related prognostic factors.

METHODS

Subjects included 215 teeth from 199 patients who had received intentional replantation in a Taiwan medical center. Patients at age under 20 years and those follow-up periods less than 6 months were excluded. The replanted teeth were followed up for a period of 6 months-120 months. Post-treatment assessments, including tooth survival and functional status, were evaluated using both clinical and radiographic examinations.

RESULTS

Kaplan-Meier survival analysis revealed the overall tooth survival rate at 4 years was 82.8%. In bivariate analysis, both root-end filling material and enamel matrix derivative (EMD) applications were found to be significant (P < 0.05). The multivariate analysis revealed that age and the presence of a sinus tract or abscess might be the predictors of treatment outcome in intentional replantation.

CONCLUSION

Intentional replantation, operated with improved modern technique, is a reliable and viable treatment with a high long-term survival rate (82.8%). If replanted teeth are diagnosed as acute or chronic apical abscess at the pre-operative examination, the risk of failure is measured 2.7 times higher than those diagnosed with other conditions. Application of EMD on the root surface of a replanted tooth may promote the formation and regeneration of periodontal apparatus, therefore increasing the functioning rate and improving the treatment outcome.

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.

Amelogenin Downregulates Interferon Gamma-Induced Major Histocompatibility Complex Class II Expression Through Suppression of Euchromatin Formation in the Class II Transactivator Promoter IV Region in Macrophages

Enamel matrix derivatives (EMDs)-based periodontal tissue regenerative therapy is known to promote healing with minimal inflammatory response after periodontal surgery, i. e., it promotes wound healing with reduced pain and swelling. It has also been reported that macrophages stimulated with amelogenin, a major component of EMD, produce various anti-inflammatory cytokines and growth factors. We previously found that stimulation of monocytes with murine recombinant M180 (rM180) amelogenin suppresses major histocompatibility complex class II (MHC II) gene expression using microarray analysis. However, the detailed molecular mechanisms for this process remain unclear. In the present study, we demonstrated that rM180 amelogenin selectively downmodulates the interferon gamma (IFNγ)-induced cell surface expression of MHC II molecules in macrophages and this mechanism mediated by rM180 appeared to be widely conserved across species. Furthermore, rM180 accumulated in the nucleus of macrophages at 15 min after stimulation and inhibited the protein expression of class II transactivator (CIITA) which controls the transcription of MHC II by IFNγ. In addition, reduced MHC II expression on macrophages pretreated with rM180 impaired the expression of T cell activation markers CD25 and CD69, T cell proliferation ability, and IL-2 production by allogenic CD4⁺ T lymphocytes in mixed lymphocyte reaction assay. The chromatin immunoprecipitation assay showed that IFNγ stimulation increased the acetylation of histone H3 lysine 27, which is important for conversion to euchromatin, as well as the trimethylation of histone H3 lysine 4 levels in the CIITA promoter IV (p-IV) region, but both were suppressed in the group stimulated with IFNγ after rM180 treatment. In conclusion, the present study shows that amelogenin suppresses MHC II expression by altering chromatin structure and inhibiting CIITA p-IV transcription activity, and attenuates subsequent T cell activation. Clinically observed acceleration of wound healing after periodontal surgery by amelogenin may be partially mediated by the mechanism elucidated in this study. In addition, the use of recombinant amelogenin is safe because it is biologically derived protein. Therefore, amelogenin may also be used in future as an immunosuppressant with minimal side effects for organ transplantation or MHC II-linked autoimmune diseases such as type I diabetes, multiple sclerosis, and rheumatoid arthritis, among others.

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.

Periodontal regeneration: a bibliometric analysis of the most influential studies

Aim: The aim of the present study is to identify the most influential research articles and their main characteristics in the specialty of periodontal regeneration. Materials & methods: The Web of Science database advance search was performed in the subject category of 'Dentistry, Oral surgery and medicine' from January 2004 to October 2018 to retrieve citations data. Results: The majority of the articles were published in journals dedicated to the specialty of periodontology. Among the top-cited articles most emphasized study types were randomized control trials (n = 25) and reviews (n = 20). Conclusion: The present bibliometric analysis provides comprehensive information regarding the contributions made in the advancement of regenerative periodontal research. The authors from developed countries and affiliated with interdisciplinary/multicenter institutions have predominantly contributed.

Infrabony defects 20 years after open flap debridement and guided tissue regeneration

AIM

Evaluation of 20-year results after open flap debridement (OFD) and guided tissue regeneration (GTR) of infrabony defects in a randomized controlled trial.

MATERIALS AND METHODS

In originally 16 periodontitis patients (baseline examination), periodontal surgery was performed in 44 infrabony defects. Polylactide acetyltributyl citrate barriers were randomly assigned to 23 out of these 44 defects (parallel). Ten of these patients (GTR) exhibited a second, contra-lateral defect (OFD) each (split-mouth). At baseline, 12, 120 and 240 ± 12 months after surgery probing depths, attachment level, bleeding on probing as well was Plaque Index, Gingival Bleeding Index and plaque control record were obtained.

RESULTS

Twelve patients contributing 38 defects were available at 240 months. At 12, 120 and 240 ± 12 months, both groups showed significant (p < 0.01) attachment gain (split-mouth: OFD: 12 months: 4.15 ± 2.93 mm; 120 months: 3.35 ± 2.37 mm, 240 months: 3.60 ± 2.55 mm; GTR: 12 months: 3.50 ± 2.47 mm; 120 months: 3.90 ± 2.76 mm, 240 months: 3.80 ± 2.69 mm; parallel: OFD: 12 months: 3.53 ± 2.04 mm; 120 months: 3.59 ± 2.54 mm, 240 months: 3.53 ± 2.50 mm; GTR: 12 months: 4.07 ± 2.88 mm; 120 months: 3.13 ± 2.22 mm, 240 months: 3.13 ± 2.22 mm). Seven teeth (3 OFD, 4 GTR) were lost. Only 1 patient out of 12 was kept in regular supportive periodontal therapy (SPT) over 20 years. The study failed to show significant attachment gain differences between both groups after 240 months.

CONCLUSIONS

Twenty years after OFD and GTR in infrabony defects in a population with lack of regular SPT attachment gains at 12 months after surgery were stable. About 82% of the initially included teeth were still in place.

WITHDRAWN: Guided tissue regeneration for periodontal infra-bony defects

BACKGROUND

Conventional treatment of destructive periodontal (gum) disease arrests the disease but does not usually regain the bone support or connective tissue lost in the disease process. Guided tissue regeneration (GTR) is a surgical procedure that specifically aims to regenerate the periodontal tissues when the disease is advanced and could overcome some of the limitations of conventional therapy.

OBJECTIVES

To assess the efficacy of GTR in the treatment of periodontal infra-bony defects measured against conventional surgery (open flap debridement (OFD)) and factors affecting outcomes.

SEARCH METHODS

We conducted an electronic search of the Cochrane Oral Health Group Trials Register, MEDLINE and EMBASE up to April 2004. Handsearching included Journal of Periodontology, Journal of Clinical Periodontology, Journal of Periodontal Research and bibliographies of all relevant papers and review articles up to April 2004. In addition, we contacted experts/groups/companies involved in surgical research to find other trials or unpublished material or to clarify ambiguous or missing data and posted requests for data on two periodontal electronic discussion groups.

SELECTION CRITERIA

Randomised, controlled trials (RCTs) of at least 12 months duration comparing guided tissue regeneration (with or without graft materials) with open flap debridement for the treatment of periodontal infra-bony defects. Furcation involvements and studies specifically treating aggressive periodontitis were excluded.

DATA COLLECTION AND ANALYSIS

Screening of possible studies and data extraction was conducted independently. The methodological quality of studies was assessed in duplicate using individual components and agreement determined by Kappa scores. Methodological quality was used in sensitivity analyses to test the robustness of the conclusions. The Cochrane Collaboration statistical guidelines were followed and the results expressed as mean differences (MD and 95% CI) for continuous outcomes and risk ratios (RR and 95% CI) for dichotomous outcomes calculated using random-effects models. Any heterogeneity was investigated. The primary outcome measure was change in clinical attachment.

MAIN RESULTS

The search produced 626 titles, of these 596 were clearly not relevant to the review. The full text of 32 studies of possible relevance was obtained and 15 studies were excluded. Therefore 17 RCTs were included in this review, 16 studies testing GTR alone and two testing GTR + bone substitutes (one study had both test treatment arms).No tooth loss was reported in any study although these data are incomplete where patient follow up was not complete. For attachment level change, the mean difference between GTR and OFD was 1.22 mm (95% CI Random Effects: 0.80 to 1.64, Chi2 for heterogeneity 69.1 (df = 15), P < 0.001, I2 = 78%) and for GTR + bone substitutes was 1.25 mm (95% CI 0.89 to 1.61, Chi2 for heterogeneity 0.01 (df = 1), P = 0.91). GTR showed a significant benefit when comparing the numbers of sites failing to gain 2 mm attachment with risk ratio 0.54 (95% CI Random Effects: 0.31 to 0.96, Chi2 for heterogeneity 8.9 (df = 5), P = 0.11). The number needed to treat (NNT) for GTR to achieve one extra site gaining 2 mm or more attachment over open flap debridement was therefore 8 (95% CI 5 to 33), based on an incidence of 28% of sites in the control group failing to gain 2 mm or more of attachment. For baseline incidences in the range of the control groups of 3% and 55% the NNTs are 71 and 4.Probing depth reduction was greater for GTR than OFD: 1.21 mm (95% CI 0.53 to 1.88, Chi2 for heterogeneity 62.9 (df = 10), P < 0.001, I2 = 84%) or GTR + bone substitutes, weighted mean difference 1.24 mm (95% CI 0.89 to 1.59, Chi2 for heterogeneity 0.03 (df = 1), P = 0.85).For gingival recession, a statistically significant difference between GTR and open flap debridement controls was evident (mean difference 0.26 mm (95% CI Random Effects: 0.08, 0.43, Chi2 for heterogeneity 2.7 (df = 8), P = 0.95), with a greater change in recession from baseline for the control group.Regarding hard tissue probing at surgical re-entry, a statistically significant greater gain was found for GTR compared with open flap debridement. This amounted to a weighted mean difference of 1.39 mm (95% CI 1.08 to 1.71, Chi2 for heterogeneity 0.85 (df = 2), P = 0.65). For GTR + bone substitutes the difference was greater, with mean difference 3.37 mm (95% CI 3.14 to 3.61).Adverse effects were generally minor although with an increased treatment time for GTR. Exposure of the barrier membrane was frequently reported with a lack of evidence of an effect on healing.

AUTHORS' CONCLUSIONS

GTR has a greater effect on probing measures of periodontal treatment than open flap debridement, including improved attachment gain, reduced pocket depth, less increase in gingival recession and more gain in hard tissue probing at re-entry surgery. However there is marked variability between studies and the clinical relevance of these changes is unknown. As a result, it is difficult to draw general conclusions about the clinical benefit of GTR. Whilst there is evidence that GTR can demonstrate a significant improvement over conventional open flap surgery, the factors affecting outcomes are unclear from the literature and these might include study conduct issues such as bias. Therefore, patients and health professionals need to consider the predictability of the technique compared with other methods of treatment before making final decisions on use. Since trial reports were often incomplete, we recommend that future trials should follow the CONSORT statement both in their conduct and reporting.There is therefore little value in future research repeating simple, small efficacy studies. The priority should be to identify factors associated with improved outcomes as well as investigating outcomes relevant to patients. Types of research might include large observational studies to generate hypotheses for testing in clinical trials, qualitative studies on patient-centred outcomes and trials exploring innovative analytic methods such as multilevel modelling. Open flap surgery should remain the control comparison in these studies.

Regeneration of the Periodontal Apparatus in Aggressive Periodontitis Patients

The purpose of this study is to evaluate and compare, retrospectively, the outcome of two different periodontal regeneration procedures in patients suffering from aggressive periodontitis (AgP). Twenty-eight patients were diagnosed with AgP, suffering from several intra-bony defects (IBD); that were treated by one of two periodontal regeneration techniques randomly assigned to each patient: a. guided tissue regeneration (GTR) or b. an application of extracted enamel matrix derivatives (EMD) combined with demineralized bone xenograft particles (DBX). Probing pocket depth (PPD), clinical attachment level (CAL), and gingival recession were recorded. Pre-treatment and follow-up (up to 10 years from the surgery) recordings were analyzed statistically within and between groups. A significant reduction was shown at time on PPD and CAL values, however, not between subject groups. CAL values decreased in all sites. At the EMD group (44 sites), CAL gain was 1.92 mm (±1.68) from pre-treatment to follow-up (p < 0.001) and at the GTR group (12 sites) CAL gain of 2.27 (±1.82) mm. In conclusion, 1⁻10 years observations have shown that surgical treatment of AgP patients by either GTR or by application of EMD/DBX results in similar successful clinical results.

Periodontal reconstructive surgery of deep intraosseous defects using an apical approach. Non-incised papillae surgical approach (NIPSA): A retrospective cohort study

BACKGROUND

The objective of this study was to compare a minimally-invasive surgical technique (MIST) and a non-incised papilla surgical approach (NIPSA) in periodontal reconstructive surgery of deep intraosseous defects.

METHODS

Data on 30 patients with a deep intraosseous defect treated with MIST (n = 15) or NIPSA (n = 15) were analyzed retrospectively. All patients met the same inclusion criteria and were treated following the same protocol, except for the surgical management of soft tissue (MIST versus NIPSA). Clinical parameters at baseline and at 1-year post-surgery, early healing at 1 week, and postoperative pain were assessed.

RESULTS

NIPSA and MIST resulted in significant clinical attachment gain (CAG) (P < 0.001) and probing depth reduction (PDr) (P < 0.001) at 1-year post-surgery. However, NIPSA resulted in significantly lower recession of the tip of the interdental papilla compared with MIST (P < 0.001). Smoking negatively influenced early healing in both techniques (P < 0.05).

CONCLUSIONS

NIPSA and MIST both resulted in significant improvements in clinical parameters. NIPSA showed significant soft tissue preservation. NIPSA may represent a promising papillae preservation technique in the treatment of intraosseous periodontal defects.

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.

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.

Evaluation of the adjunctive effect of platelet-rich fibrin to enamel matrix derivative in the treatment of intrabony defects. Six-month results of a randomized, split-mouth, controlled clinical study

AIM

This study aimed to compare the results obtained with enamel matrix derivative (EMD) and EMD + platelet-rich fibrin (PRF) in the treatment of intrabony defects (IBDs) in chronic periodontitis patients.

MATERIALS AND METHODS

Using a split-mouth design, 28 paired IBDs were randomly treated either with EMD or with EMD + PRF. Clinical and radiographic measurements including clinical attachment level (CAL), probing depth (PD), gingival recession (GR), defect depth (DD), defect width (DW) and defect angle (DA) were recorded at baseline (BL) and at six months following therapy.

RESULTS

BL clinical and radiographic measurements were similar for EMD and EMD + PRF groups. Although postsurgical measurements revealed significant reduction for PD and CAL in both groups, no intergroup difference was detected. When EMD and EMD + PRF groups were compared, defect fill was not also statistically different.

CONCLUSIONS

Both therapies resulted in significant clinical improvement in IBD treatment. Addition of PRF did not improve the clinical and radiographic outcomes.