Long-term results of guided tissue regeneration therapy in the treatment of class II furcation defects: a randomized clinical trial

Radiographic Evaluation of Regeneration Strategies for the Treatment of Advanced Mandibular Furcation Defects: A Retrospective Study

Teeth with furcation involvement (FI) present a higher risk of loss and are difficult to maintain. This study evaluated the efficacy of furcation defect regeneration (FDR) as a regeneration strategy. Pre-operative and 6-month postoperative radiographs were collected from patients receiving regeneration therapy for mandibular teeth with degree II and early degree III FI. The linear furcation involvement (LFI), ratio of LFI (RLI), LFI and RLI adjusted bythe alveolar bone crest (ABC), and radiographic intensity were assessed. The effects of demographic characteristics, regeneration treatment strategies, the relationship between furcation and ABC, and adjacent intrabony defect regeneration (AIDR) were evaluated using a generalized linear model and logistic regression. The results demonstrated that 1.5 mm adjusted LFI and 40% adjusted RLI were achieved in both pure furcation defects and combined furcation–angular defects by the combination of bone replacement grafts (BRG) and enamel matrix derivatives (EMD) or collagen membrane (CM); deproteinized bovine bone matrix (DBBM) showed a superior outcome among BRG. In combined furcation–angular defects, EMD appeared more beneficial than CM, and AIDR significantly promoted adjusted LFI and RLI. In conclusion, DBBM with EMD or CM was effective for FDR, and AIDR had a positive effect on FDR in the combined furcation–angular defect.

Periodontal regeneration: is it still a goal in clinical periodontology?

In the last decades, Periodontal Regeneration has been one of the most discussed topics in Periodontics, attracting the attention of researchers and clinicians. This can be justified by the evident and continuous progress observed in the field, characterized by a better understanding of the biological mechanisms involved, significant improvement of operative and technical principles, and the emergence of a wide range of biomaterials available for this purpose. Together, these aspects put the theme much in evidence in the search for functional and esthetic therapeutic solutions for periodontal tissue destruction. Despite the evident evolution, periodontal regeneration may be challenging and require the clinician to carefully evaluate each case before making a therapeutic decision. With a critical reassessment of the clinical and preclinical literature, the present study aimed to discuss the topic to answer whether Periodontal Regeneration is still a goal in clinical periodontology. The main aspects involved in the probability of success or failure of regenerative approaches were considered. A greater focus was given to intrabony and furcation defects, clinical conditions with greater therapeutic predictability. Aspects such as more appropriate materials/approaches, long-term benefits and their justification for a higher initial cost were discussed for each condition. In general, deep intrabony defects associated with residual pockets and buccal/lingual class II furcation lesions have predictable and clinically relevant results. Careful selection of the case (based on patient and defect characteristics) and excellent maintenance are essential conditions to ensure initial and long-term success.

Experimental and clinical studies on regenerative periodontal therapy

The recognition of a periodontal therapy as a regenerative procedure requires the demonstration of new cementum, periodontal ligament, and bone coronal to the base of the defect. A diversity of regenerative strategies has been evaluated, including root surface conditioning, bone grafts and bone substitute materials, guided tissue regeneration, enamel matrix proteins, growth/differentiation factors, combined therapies and, more recently, tissue-engineering approaches. The aim of this chapter of Periodontology 2000 is to review the research carried out in Latin America in the field of periodontal regeneration, focusing mainly on studies using preclinical models (animal models) and randomized controlled clinical trials. This review may help clinicians and researchers to evaluate the current status of the therapies available and to discuss the challenges that must be faced in order to achieve predictable periodontal regeneration in clinical practice.

Comparative study of nonabsorbable and absorbable barrier membranes in periodontal osseous defects by guided tissue regeneration

BACKGROUND

Periodontal invasion of furcation area in multirooted teeth represents one of the most demanding therapeutic challenges in periodontics. Furcation therapy includes various treatment modalities like either maintenance or elimination of furcation or increased access to furcation area. Recent treatment modalities include regenerative procedures like placement of different type of bone grafts with nonabsorbable or absorbable barrier membranes, through guided tissue regeneration. This study compared the clinical efficacy of nonabsorbable barrier membrane with absorbable membrane when used with hydroxyapatite bone graft (G-Graft) in grade II buccal furcation defects in mandibular 1st molars.

MATERIALS AND METHODS

Fourteen subjects with bilateral grade II buccal furcation defects in lower 1st molars were selected and treated in a split-mouth design. After phase I therapy, molars were divided randomly into two groups for the treatment with either resorbable or nonresorbable membrane in conjunction with G-Graft in both groups.

RESULTS

All the clinical parameters recorded showed statistically significant improvement in both the groups but no significant difference between two groups was observed.

CONCLUSION

Both nonabsorbable and absorbable barrier membranes were equally effective in treating grade II buccal furcation defects in lower molars when used in conjunction with G-Graft except with respect to horizontal bone fill in which absorbable barrier membrane showed better results.

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

BACKGROUND

The aim of this review is to present the available evidence regarding the effectiveness of different regenerative approaches for the treatment of furcation defects in specific clinical scenarios compared with conventional surgical therapy to provide clinical guidelines for the therapeutic management of furcation defects and to identify priorities for future research that may advance the understanding of periodontal regenerative medicine.

METHODS

A comprehensive search based on predetermined eligibility criteria was conducted to identify human original studies and systematic reviews on the topic of periodontal regeneration of furcation defects. Two reviewers independently screened the title and abstract of the entries yielded from the initial search. Subsequently, both reviewers read the full-text version of potentially eligible studies, made a final article selection, and extracted the data of the selected studies considering specific clinical scenarios. The clinical scenarios contemplated in this review included the following: 1) facial and interproximal Class I defects in maxillary molars; 2) facial and lingual Class I defects in mandibular molars; 3) facial and interproximal Class II furcation defects in maxillary molars; 4) facial and lingual Class II furcation defects in mandibular molars; 5) Class III furcation defects in maxillary molars; 6) Class III furcation defects in mandibular molars; and 7) Class I, II, or III furcation defects in maxillary premolars. Endpoints of interest included different clinical, radiographic, microbiologic, histologic, and patient-reported outcomes.

RESULTS

The initial search yielded a total of 1,500 entries. The final selection consisted of 150 articles, of which six were systematic reviews, 109 were clinical trials, 27 were case series, and eight were case reports. A summary of the main findings of previously published systematic reviews and the available evidence relative to the indication of regenerative approaches for the treatment of furcation defects compared with conventional surgical therapy are presented. Given the marked methodologic heterogeneity and the wide variety of materials and techniques applied in the selected clinical trials, the conduction of a meta-analysis was not viable.

CONCLUSIONS

On the basis of the reviewed evidence, the following conclusions can be drawn. 1) Periodontal regeneration has been demonstrated histologically and clinically for the treatment of maxillary facial or interproximal and mandibular facial or lingual Class II furcation defects. 2) Although periodontal regeneration has been demonstrated histologically for the treatment of mandibular Class III defects, the evidence is limited to one case report. 3) Evidence supporting regenerative therapy in maxillary Class III furcation defects in maxillary molars is limited to clinical case reports. 4) In Class I furcation defects, regenerative therapy may be beneficial in certain clinical scenarios, although most Class I furcation defects may be successfully treated with non-regenerative therapy. 5) Future research efforts should be primarily directed toward the conduction of clinical trials to test novel regenerative approaches that place emphasis primarily on patient-reported outcomes and also on histologic demonstration of periodontal regeneration. Investigators should also focus on understanding the influence that local, systemic, and technical factors may have on the outcomes of regenerative therapy in furcation defects.

Treatment of grade II furcation involvement using resorbable guided tissue regeneration membrane: A six-month study

Aims:

The present study was undertaken to evaluate the effectiveness of the combination of hydroxyapatite and β-tricalcium phosphate bone alloplast with bioresorbable guided tissue regeneration membrane for the treatment of mandibular grade II furcation defects.

Settings and Design:

A total of eight patients, four females and four males, in the age group of 18 to 65 years, with bilateral buccal grade II furcation defects in the mandibular molars, participated in the study.

Materials and Methods:

The following clinical measurements were recorded at baseline as well as three and six months post surgery: The Turesky-Gilmore-Glickman modification of the Quigley Hein plaque index, the Loe and Silness gingival index, Relative Clinical Attachment Level Vertical Probing Depth in the mid-furcation area, and Horizontal Probing Depth in the mid-furcation area.

Statistical analysis:

Pairwise comparisons within the groups were done by applying the independent student t test. Comparisons were also drawn between the test and the control groups by applying the independent student t test.

Results:

The mean gain in the relative clinical attachment levels in the test and control groups, at the end of six months, were 2.50 and 1.63 mm, respectively. The mean change in the horizontal probing depth values at the end of six months in the test and control groups were 2.88 and 1.63 mm, respectively. The mean reduction in the vertical probing depth values in the test and control groups were 1.50 and 1.38 mm, respectively.

Conclusions:

The resorbable GTR membrane with bone material was more effective than open debridement alone, in the treatment of furcation defects.

Clinical and radiological evaluation of human osseous defects (mandibular grade ii furcation involvement) treated with bioresorbable membrane: vicryl mesh

AIM

The purpose of the present study was to evaluate clinical and radiological healing effects after treatment of class II furcation defects using bioresorbable periodontal mesh barriers.

MATERIALS AND METHODS

The patients for the following study were selected from Outpatient, Department of Periodontics, College of Dental Sciences, Davanagere, Karnataka.

INCLUSION CRITERIA

1. Patients with age group between 18 and 60 years. 2. Patients who were nonsmokers. 3. Patients who had not undergone any type of periodontal therapy 6 months prior to initial examination. 4. Patients diagnosed as advanced periodontitis having mandibular grade II furcation involvement (Glickman 1953) clinically and radiologically.

EXCLUSION CRITERIA

1. Patients who required antibiotic prophylaxis. 2. Patients allergic to tetracycline and/ or chlorhexidine. 3. Pregnant and lactating mother. 4. Patient showing unacceptable oral hygiene during presurgical (phase 1) therapy.

RESULTS

In this study clinical parameters were compared and attempt was made to compare the results radiographically too, with the limitations, the present study showed that the use of resorbable periodontal mesh barriers for GTR therapy at class II furcations resulted in reduction of furcation involvement.

CONCLUSION

Therefore it appears that a patient with class II furcations involvement benefits from barrier treatment, because results are superior to conventional treatment without barriers.

CLINICAL SIGNIFICANCE

The present study was taken up to evaluate the clinical effects of GTR therapy of class II furcations using bioresorbable periodontal mesh barriers.

Regeneration of periodontal tissues: guided tissue regeneration

The concept that only fibroblasts from the periodontal ligament or undifferentiated mesenchymal cells have the potential to re-create the original periodontal attachment has been long recognized. Based on this concept, guided tissue regeneration has been applied with variable success to regenerate periodontal defects. Quantitative analysis of clinical outcomes after guided tissue regeneration suggests that this therapy is a successful and predictable procedure to treat narrow intrabony defects and class II mandibular furcations, but offers limited benefits in the treatment of other types of periodontal defects.

Guided tissue regeneration may modulate gene expression in periodontal intrabony defects: a human study

BACKGROUND AND OBJECTIVE

Guided tissue regeneration has been shown to lead to periodontal regeneration, however, the mechanisms involved remain to be clarified. The present study was carried out to assess the expression of genes involved in the healing process of periodontal tissues in membrane-protected vs. nonprotected intrabony defects in humans.

MATERIAL AND METHODS

Thirty patients with deep intrabony defects (> or = 5 mm, two or three walls) around teeth that were scheduled for extraction were selected and randomly assigned to receive one of the following treatments: flap surgery alone (control group) or flap surgery plus guided tissue regeneration (expanded polytetrafluorethylene (e-PTFE) membrane) (test group). Twenty-one days later, the newly formed tissue was harvested and quantitatively assessed using the polymerase chain reaction assay for the expression of the following genes: alkaline phosphatase, receptor activator of nuclear factor-kappa B ligand, osteoprotegerin, osteopontin, osteocalcin, bone sialoprotein, basic fibroblast growth factor, interleukin-1, interleukin-4, interleukin-6, matrix metalloproteinase-2 and matrix metalloproteinase-9.

RESULTS

Data analysis demonstrated that mRNA levels for alkaline phosphatase, receptor activator of nuclear factor-kappa B ligand, osteoprotegerin, osteopontin, bone sialoprotein, basic fibroblast growth factor, interleukin-1, interleukin-6, matrix metalloproteinase-2 and matrix metalloproteinase -9 were higher in the sites where guided tissue regeneration was applied compared with the control sites (p < 0.05), whereas osteocalcin mRNA levels were lower (p < 0.05). No difference was observed in interleukin-4 mRNA levels between control and test groups.

CONCLUSION

Within the limits of this study, it can be concluded that genes are differentially expressed in membrane barrier-led periodontal healing when compared with flap surgery alone, and this may account for the clinical outcome achieved by guided tissue regeneration.

Effects of a Mineralized Human Cancellous Bone Allograft in Regeneration of Mandibular Class II Furcation Defects

BACKGROUND

A solvent-preserved, mineralized human cancellous bone allograft (MBA) was recently developed. However, its effect in regenerating furcation defects remains to be determined. Hence, the aim of the study is to evaluate the effects of this newly introduced MBA, with and without a bioabsorbable collagen membrane, for the treatment of mandibular class II furcation defects.

METHODS

Thirty subjects with Hamp's Class II buccal or lingual furcation defects in lower molars were randomly assigned to open flap debridement (OFD), MBA, or MBA with a bioabsorbable collagen membrane (guided tissue regeneration [GTR]+MBA) groups. Clinical and defect measurements were obtained at the initial visit and at 6-month reentry surgeries. The data were analyzed for intra- and intergroup comparisons and associations of treatment with probability of clinical improvement.

RESULTS

Out of a total of 30 subjects, 27 individuals completed the study. Vertical bone fill (VBF) was -1.6+/-2.1 mm in OFD, 1.9+/-1.4 mm in MBA, and 0.7+/-0.9 mm in GTR+MBA groups. VBF in MBA and GTR + MBA groups was significantly higher than that in the OFD group (P<0.05). Horizontal bone fill (HBF) was 0.2+/-1.7 mm, 1.1+/-0.9 mm, and 1.1+/-0.9 mm for OFD, MBA, and GTR+MBA groups, respectively. However, HBF, recession, clinical attachment level gain, and probing depth reduction at furcations showed no differences among groups.

CONCLUSIONS

Results obtained from this study indicate that solvent-preserved, mineralized human cancellous allograft, with or without collagen membrane, can significantly improve bone fill in mandibular Class II furcation defects. In addition, initial vertical defect depth was found to be the only factor that was associated with a higher probability of clinical improvement.

Regeneration of class II furcation defects: determinants of increased success

One of the most important indications for guided tissue regeneration (GTR) treatment is class II furcation lesion. However, periodontal regeneration of this type of defect, although possible, is not considered totally predictable, especially in terms of complete bone fill. Many factors may account for variability in the response to regenerative therapy in class II furcation. The purpose of this review is to assess the prognostic significance of factors related to the patient (smoking, stress, diabetes mellitus, acquired immunodeficiency syndrome and other acute and debilitating diseases, and the presence of multiple deep periodontal pockets), local factors (furcal anatomy, defect morphology, thickness of gingival tissue and tooth mobility), surgical treatment (infection control, bone replacement grafts combined with barriers or GTR alone, type of barrier and surgical technique), and postoperative period (plaque control, membrane exposure, membrane retrieval and a regular supportive periodontal care program) for successful of GTR in class II furcations.

Root resorption and ankylosis associated with guided tissue regeneration

BACKGROUND

Root resorption and ankylosis have been reported rarely as sequelae to guided tissue regeneration (GTR). The authors describe a clinical case of root resorption following GTR that involved the use of a bioabsorbable membrane.

CASE DESCRIPTION

Two years after GTR was performed on a Class II furcation defect, the clinical examination revealed root resorption reaching the pulp chamber. The furcation defect was filled with epithelium and connective tissue, which contained inflammatory infiltrate and fragments of the membrane. The authors also observed areas of the tooth that exhibited points of ankylosis and root resorption.

CLINICAL IMPLICATIONS

Clinical trials have reported favorable clinical and histologic results with GTR. However, this case report, along with other case reports and studies in animals, suggests a high risk of root resorption and ankylosis after GTR, which could limit the indications for this technique.

Comparison Between Subtraction Radiography and Conventional Radiographic Interpretation During Long-Term Evaluation of Periodontal Therapy in Class II Furcation Defects

BACKGROUND

Limited information comparing digital subtraction radiographic assessment with conventional radiographic interpretation is available from longitudinal clinical trials. The aim of this study was to evaluate the ability to detect periodontal bone changes during the long-term maintenance of Class II furcation defects by conventional radiographic interpretation compared to interpretation of digital subtraction images.

METHODS

Standardized radiographs of 18 Class II furcation defects in mandibular molars were taken at baseline and at 6, 12, 18, and 24 months after non-resective periodontal surgery. Conventional radiographic and digital subtraction interpretations were performed masked, respectively, by two and three experienced examiners, according to the following categories: bone gain; bone loss; unchanged appearance; and impossible to visualize. Percent concordance and the kappa statistic value (kappa) were computed.

RESULTS

Conventional radiographic and digital subtraction interpretation images resulted in 72 decisions for each examiner. The visual interpretation of digital subtraction images by two examiners revealed the same results. The interpretation of conventional radiographic images showed a low concordance between examiners (kappa < 0.40) at all examinations. The concordance between subtraction radiography and conventional radiographic interpretation was also low for all examiners (kappa < 0.36) at all examinations. Using subtraction radiography as a reference, bone changed and bone unchanged were diagnosed correctly in 47.2% of cases by examiner A, in 43.1% by examiner B, and in 38.9% by examiner C.

CONCLUSION

It can be concluded that conventional radiographic interpretation is a more subjective and inaccurate method of detecting periodontal bone changes in Class II furcation defects in mandibular molars when compared with subtraction radiography.

The relationship between radiographic and clinical parameters in periodontal maintenance in class II furcation defects

The goal of the present study was to investigate the relationship between probing and radiographic parameters, and the reliability of repeated longitudinal periodontal probing measurements for early diagnosis of periodontal breakdown in class II furcation defects. Eighteen class II furcation defects in lower molars were included in this study. Standardized radiographs and clinical measurements, relative vertical clinical attachment level (CAL-v) and probing depth (PD) were obtained immediately before periodontal surgeries and at 6, 12, 18, and 24 months after surgery. A total of 72 pairs of radiographs were subtracted following correction for contrast and planar geometric discrepancies, and the bone loss/gain (in mm) was measured. There was no statistically significant correlation between CAL-v and bone height (BH) measurements. A statistically significant correlation for PD reduction at 24 months and BH increase at 18 months was found (r = 0.5, p < 0.05). These results suggest that clinical measurements and radiographic bone height reflect different features of periodontal destruction and periodontal healing, and repeated longitudinal measurements of vertical clinical attachment level are not reliable for early diagnosis of periodontal breakdown in class II furcation defects.