Comparison of enamel matrix proteins and bioabsorbable membranes in the treatment of intrabony periodontal defects. A split-mouth study

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.

In-vitro antibiofilm activity of chlorhexidine digluconate on polylactide-based and collagen-based membranes

Background

In Guided Tissue Regeneration (GTR), barrier membranes are used to allow selective cell populations to multiply and to promote periodontal regeneration. A frequent complication is membrane exposure to the oral cavity followed by bacterial colonization. The purpose of this in-vitro-study was to elucidate, if rinsing with a chlorhexidine digluconate solution (CHX) prevents bacterial adhesion, and whether it interferes with attachment of periodontal ligament (PDL) fibroblasts and epithelial cells to membrane surfaces.

Methods

Firstly, two bioresorbable membranes (polylactide-based and collagen-based) were dipped into 0.06% CHX and 0.12% CHX, before biofilms (2-species representing periodontal health, 6-species representing a periodontitis) were formed for 2 h and 8 h. Subsequently, colony forming units (cfu) were counted. Secondly, the membranes were treated with CHX and inoculated in bacteria suspension two-time per day for 3 d before cfu were determined. In additional series, the influence of CHX and bacterial lysates on attachment of epithelial cells and PDL fibroblasts was determined. Parameter-free tests were applied for statistical analysis.

Results

Cfu in “healthy” biofilms did not differ between the two membranes, more cfu were counted in “periodontitis” biofilm on collagen than on polylactide membranes. One-time dipping of membranes into CHX solutions did not markedly influence the cfu counts of both biofilms on polylactide membrane; those on collagen-based membrane were significantly reduced with being 0.12% CHX more active than 0.06% CHX. More-fold CHX dipping of membranes reduced concentration-dependent the cfu counts of both biofilms on both membranes. In general, the number of attached gingival epithelial cells and PDL fibroblasts was higher on collagen than on polylactide membrane. Lysates of the periodontopathogenic bacteria inhibited attachment of PDL fibroblasts to membranes. CHX decreased in a concentration-dependend manner the number of attached gingival epithelial cells and PDL fibroblasts.

Conclusions

The present in-vitro results appear to indicate that membranes in GTR should only be used when bacteria being associated with periodontal disease have been eliminated. An exposure of the membrane should be avoided. Rinsing with CHX may prevent or at least retard bacterial colonization on membrane exposed to the oral activity. However, a certain negative effect on wound healing cannot be excluded.

Early wound healing outcomes after regenerative periodontal surgery with enamel matrix derivatives or guided tissue regeneration: a systematic review

BACKGROUND

Proper wound healing after regenerative surgical procedures is an essential issue for clinical success. Guided tissue regeneration (GTR) and application of enamel matrix derivatives (EMD) are common means to regenerate periodontal tissues. Both methods bear considerable advantages due to their special characteristics, but also go along with certain disadvantages. Today, there is no consensus in the literature whether GTR or EMD show better results regarding early wound healing, which is considered a crucial stage in periodontal regeneration. Therefore, the aim of the present systematic review was to compare the early wound healing after regenerative periodontal surgery with either EMD or GTR treatment.

METHODS

An electronic literature search in PubMed was performed to identify randomized clinical trials (RCTs) or clinical trials (CTs) comparing regenerative surgery employing EMD and/or GTR in patients with chronic periodontitis. Among the finally included studies, a qualitative and quantitative data extraction regarding early wound healing parameters was performed. Primary outcome parameters were early wound healing index (EWH), flap dehiscence, membrane exposure, suppuration and abscess formation during the first 6 weeks. As secondary parameters, swelling and allergic reactions were assessed.

RESULTS

Seven studies reporting 220 intrabony periodontal defects in 199 patients were analysed. Flap dehiscence was observed in two studies in 12% of the GTR treated sites and in 10.3% of those treated with EMD. Membrane exposure was evaluated in five studies and was registered in the 28.8% of the defects, while no dehiscence was reported on the EMD group. Swelling was reported only in one study in 8/16 GTR sites and 7/16 EMD sites. Due to considerable heterogeneity of parameters no meta-analysis was possible.

CONCLUSIONS

Due to considerable heterogeneity of the published studies a clear beneficial effect of the EMD on the early wound healing outcomes after surgical treatment of periodontal intrabony defects cannot be confirmed. Standardized RCT studies are needed in order to allow for proper comparison of early wound healing after both types of surgical approaches.

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.

Tissue engineered periodontal products

Attainment of periodontal regeneration is a significant clinical goal in the management of advanced periodontal defects arising from periodontitis. Over the past 30 years numerous techniques and materials have been introduced and evaluated clinically and have included guided tissue regeneration, bone grafting materials, growth and other biological factors and gene therapy. With the exception of gene therapy, all have undergone evaluation in humans. All of the products have shown efficacy in promoting periodontal regeneration in animal models but the results in humans remain variable and equivocal concerning attaining complete biological regeneration of damaged periodontal structures. In the early 2000s, the concept of tissue engineering was proposed as a new paradigm for periodontal regeneration based on molecular and cell biology. At this time, tissue engineering was a new and emerging field. Now, 14 years later we revisit the concept of tissue engineering for the periodontium and assess how far we have come, where we are currently situated and what needs to be done in the future to make this concept a reality. In this review, we cover some of the precursor products, which led to our current position in periodontal tissue engineering. The basic concepts of tissue engineering with special emphasis on periodontal tissue engineering products is discussed including the use of mesenchymal stem cells in bioscaffolds and the emerging field of cell sheet technology. Finally, we look into the future to consider what CAD/CAM technology and nanotechnology will have to offer.

The use of a membrane and/or a bone graft may not improve the effects of enamel matrix derivatives in infrabony defects

SELECTION CRITERIA

This study undertook a network meta-analyses of studies comparing the effect of enamel matrix derivatives when used alone or in combination with bone grafts and/or membranes in the treatment of infrabony periodontal defects. A literature search was conducted on several medical databases (Medline, EMBASE, LILACS, and CENTRAL) and also on regular Web search engines (Google). Twenty-eight randomized controlled trials (RCTs) were included in the review. For study inclusion, the patients (or the periodontal defects) had to be randomly assigned to the test or control group and there had to have been follow-up for a minimum of 6 months.

KEY STUDY FACTOR

Treatment of infrabony defects with emdogain alone and with emdogain plus membrane and/or bone graft.

MAIN OUTCOME MEASURE

The primary outcomes were reduction in pocket probing depth (PD), gain of clinical attachment level (CAL), and infrabony defect depth recorded at least 6 months after the procedure was completed.

MAIN RESULTS

Twenty-eight publications were included in this systematic review with meta-analysis. In the initial search, 337 articles were found: 35 articles were found on medical databases (PubMed, EMBASE, LILACS, Central); 1 article was found through the gray search (Google); and 1 article was found through the electronic search in 3 periodontal journals. Of the 337 articles, 306 were excluded at the assessment of titles and abstracts phase because they were either case reports or they were not considered RCTs. The remaining 31 articles were examined in their full length (not just abstracts and titles). Three of these articles were excluded because they were not RCTs or because the adjunctive treatment was not considered regenerative. Because many variations of the treatment were used in the selected studies, the authors used network meta-analysis for the statistical synthesis of direct and indirect comparisons. Enamel matrix derivatives (EMDs) plus bone grafts and EMDs plus membranes attained 0.24 mm and 0.07 mm more PPD reduction than EMDs alone, respectively. For CAL gain, EMDs plus bone grafts and EMDs plus membranes attained 0.46 mm and 0.15 mm, respectively.

CONCLUSIONS

The analysis shows that adding membranes and/or bone grafts to the EMDs does not provide significant benefits in the treatment of periodontal defects.

Five years clinical results following treatment of human intra-bony defects with an enamel matrix derivative: a randomized controlled trial

INTRODUCTION

Emdogain® represents an extracellular matrix derivative that controls and promotes periodontal regeneration. Several studies have demonstrated that the treatment of periodontal defects with Emdogain® leads to improvements in clinical parameters. However, long-time clinical trials establishing clinical usefulness of Emdogain® are scarce. Therefore, the present randomized split mouth, controlled study was undertaken to evaluate the effectiveness of Emdogain® as an adjunct to open flap debridement for the treatment of intra-bony defects over a period of 5 years.

MATERIALS AND METHODS

The study population consisted of 15 chronic periodontitis patients with bilateral interproximal osseous defects. The test group was treated by open flap debridement with EDTA 24% (PrefGel®) followed by enamel matrix derivative (Emdogain®). The control group was treated by open flap debridement with EDTA 24% (PrefGel®).

RESULTS

After 1 and 5 years, both the test and control groups showed significant mean PPD reduction. A greater reduction in mean Probing Pocket Depth (PPD) was observed in the test group (3.84 ± 1.05) as compared to the control group (1.92 ± 0.35). The mean Clinical Attachment Level (CAL) gain of 3.18 ± 0.87 mm was observed in the test group, while the control group displayed mean CAL gain of 1.60 ± 0.54 mm. The observed differences were found to be statistically significant in both the groups (p < 0.05). Percentage bone fill was significantly increased at 12 months post-surgery in test group (66.66 ± 7.8%) as compared to control group (31.71 ± 4.1%).

CONCLUSION

The treatment with Emdogain resulted in a significantly higher CAL gain and PPD reduction in comparison with OFD and PrefGel®.

Enamel matrix protein derivatives: role in periodontal regeneration

The role of regenerative periodontal therapy is the reconstitution of lost periodontal structures, ie, new formation of root cementum, periodontal ligament, and alveolar bone. The outcome of basic research has pointed to the important role of enamel matrix protein derivative (EMD) in periodontal wound healing. Histologic results from animal and human studies have shown that treatment with EMD promotes periodontal regeneration. Moreover, clinical studies have indicated that treatment with EMD positively influences periodontal wound healing in humans. The goal of this paper is to review the existing literature on EMD.

Clinical effect of autologous platelet-rich fibrin in the treatment of intra-bony defects: a controlled clinical trial

AIM

Platelet-rich fibrin (PRF) may be considered as a second-generation platelet concentrate widely used to accelerate soft and hard tissue healing because of presence of many growth factors. The present study aimed to investigate the clinical and radiological effectiveness of autologous PRF in the treatment of intra-bony defects of chronic periodontitis patients.

MATERIAL AND METHODS

Thirty-two intra-bony defects (one site/patient) were treated either with autologous PRF or a conventional open flap debridement alone. Clinical parameters such as plaque index (PI), sulcus bleeding index (SBI), probing depth (PD), clinical attachment level (CAL) and gingival marginal level (GML) were recorded at baseline and 9 months post-operatively. In both the groups, by using the image analysis software intra-bony defect fill was calculated on standardized radiographs (from the baseline and 9 months).

RESULTS

For all clinical and radiographic parameters test group was performed better than control group, and the difference was found to be statistically significant. Furthermore, images analysis revealed significantly greater bone fill in the test group compared with control (46.92%versus 28.66 %). Mean PD reduction (4.56 ± 0.37>3.56 ± 0.27) and CAL gain (3.69 ± 0.44>2.13 ± 0.43) in test group was found to be more compared with that of control group. In the test group, PD of >4 mm has highest percentage of PD reduction (68.9%) and CAL gain (61.6%). On frequency distribution analysis, there was no more difference for PD reduction in both the groups but CAL gain was much more in the test group than the control group.

CONCLUSIONS

Within the limit of the present study, there was greater reduction in PD, more CAL gain and greater intra-bony defect fill at sites treated with PRF than the open flap debridement alone.

Effects of enamel matrix derivative and transforming growth factor-β1 on human osteoblastic cells

BACKGROUND

Extracellular matrix proteins are key factors that influence the regenerative capacity of tissues. The objective of the present study was to evaluate the effects of enamel matrix derivative (EMD), TGF-β1, and the combination of both factors (EMD+TGF-β1) on human osteoblastic cell cultures.

METHODS

Cells were obtained from alveolar bone of three adult patients using enzymatic digestion. Effects of EMD, TGF-β1, or a combination of both were analyzed on cell proliferation, bone sialoprotein (BSP), osteopontin (OPN) and alkaline phosphatase (ALP) immunodetection, total protein synthesis, ALP activity and bone-like nodule formation.

RESULTS

All treatments significantly increased cell proliferation compared to the control group at 24 h and 4 days. At day 7, EMD group showed higher cell proliferation compared to TGF-β1, EMD + TGF-β1 and the control group. OPN was detected in the majority of the cells for all groups, whereas fluorescence intensities for ALP labeling were greater in the control than in treated groups; BSP was not detected in all groups. All treatments decreased ALP levels at 7 and 14 days and bone-like nodule formation at 21 days compared to the control group.

CONCLUSIONS

The exposure of human osteoblastic cells to EMD, TGF-β1 and the combination of factors in vitro supports the development of a less differentiated phenotype, with enhanced proliferative activity and total cell number, and reduced ALP activity levels and matrix mineralization.

The use of a membrane and/or a bone graft may not improve the effects of enamel matrix derivatives in infrabony defects

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Do bone grafts or barrier membranes provide additional treatment effects for intrabony lesions treated with enamel matrix derivatives? A network meta-analysis of randomized controlled trails. Tu Y-K, Woolston A, Faggion CM Jr. J Clin Periodontol 2010;37:59-79.

REVIEWER

Simone Verardi, DDS, MSD.

PURPOSE/QUESTION

Do membranes and bone grafts improve the outcomes in the treatment of intrabony defects when they are used in combination with enamel matrix derivatives?

SOURCE OF FUNDING

Government: Higher Education Funding Council for England (HEFCE) and United Kingdom Research Council Fellowship.

TYPE OF STUDY/DESIGN

Systematic review with meta-analysis of data.

LEVEL OF EVIDENCE

Level 2: Limited-quality patient-oriented evidence.

STRENGTH OF RECOMMENDATION GRADE

Grade B: Inconsistent or limited-quality patient-oriented evidence.

Treatment of class III multiple gingival recessions: a randomized-clinical trial

BACKGROUND

The aim of this controlled randomized split-mouth study was to evaluate whether a modified tunnel/connective tissue graft (CTG) technique - enamel matrix derivative (EMD) combination will improve the treatment of multiple class III recession when compared with the same technique alone.

MATERIALS AND METHODS

Twenty healthy subjects with a mean age of 31.7 years, were enrolled for the trial in a university periodontal clinic. Patients with at least three adjacent gingival recessions on both sides of the mouth were treated with a modified tunnel/CTG technique. On the test side, an EMD was used in addition. Clinical parameters were measured at baseline, 28 days, 3, 6 and 12 months after the surgery. Results are presented at the subject level.

RESULTS

The mean root coverage from baseline to 1 year post-surgery was 82% for the test group and 83% for the control group. Complete root coverage was achieved at 1 year in eight (38%) of the 20 surgeries (experimental and control group).

CONCLUSIONS

One-year results indicate that the modified tunnel/CTG technique is predictable for the treatment of multiple class III recession-type defects. The addition of EMD does not enhance the mean clinical outcomes.

Enamel matrix derivative (Emdogain(R)) for periodontal tissue regeneration in intrabony defects

BACKGROUND

Periodontitis is a chronic infective disease of the gums caused by bacteria present in dental plaque. This condition induces the breakdown of the tooth supporting apparatus until teeth are lost. Surgery may be indicated to arrest disease progression and regenerate lost tissues. Several surgical techniques have been developed to regenerate periodontal tissues including guided tissue regeneration (GTR), bone grafting (BG) and the use of enamel matrix derivative (EMD). EMD is an extract of enamel matrix and contains amelogenins of various molecular weights. Amelogenins are involved in the formation of enamel and periodontal attachment formation during tooth development.

OBJECTIVES

To test whether EMD is effective, and to compare EMD versus GTR, and various BG procedures for the treatment of intrabony defects.

SEARCH STRATEGY

We searched the Cochrane Oral Health Group Trials Register, CENTRAL, MEDLINE and EMBASE. Several journals were handsearched. No language restrictions were applied. Authors of randomised controlled trials (RCTs) identified, personal contacts and the manufacturer were contacted to identify unpublished trials. Most recent search: February 2009.

SELECTION CRITERIA

RCTs on patients affected by periodontitis having intrabony defects of at least 3 mm treated with EMD compared with open flap debridement, GTR and various BG procedures with at least 1 year follow up. The outcome measures considered were: tooth loss, changes in probing attachment levels (PAL), pocket depths (PPD), gingival recessions (REC), bone levels from the bottom of the defects on intraoral radiographs, aesthetics and adverse events. The following time-points were to be evaluated: 1, 5 and 10 years.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two authors. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CI). It was decided not to investigate heterogeneity, but a sensitivity analysis for the risk of bias of the trials was performed.

MAIN RESULTS

Thirteen trials were included out of 35 potentially eligible trials. No included trial presented data after 5 years of follow up, therefore all data refer to the 1-year time point. A meta-analysis including nine trials showed that EMD treated sites displayed statistically significant PAL improvements (mean difference 1.1 mm, 95% CI 0.61 to 1.55) and PPD reduction (0.9 mm, 95% CI 0.44 to 1.31) when compared to placebo or control treated sites, though a high degree of heterogeneity was found. Significantly more sites had < 2 mm PAL gain in the control group, with RR 0.53 (95% CI 0.34 to 0.82). Approximately nine patients needed to be treated (NNT) to have one patient gaining 2 mm or more PAL over the control group, based on a prevalence in the control group of 25%. No differences in tooth loss or aesthetic appearance as judged by the patients were observed. When evaluating only trials at a low risk of bias in a sensitivity analysis (four trials), the effect size for PAL was 0.62 mm (95% CI 0.28 to 0.96), which was less than 1.1 mm for the overall result. Comparing EMD with GTR (five trials), GTR showed statistically significant more postoperative complications (three trials, RR 0.12, 95% CI 0.02 to 0.85) and more REC (0.4 mm 95% CI 0.15 to 0.66). The only trial comparing EMD with a bioactive ceramic filler found statistically significant more REC (-1.60 mm, 95% CI -2.74 to -0.46) at the EMG treated sites.

AUTHORS' CONCLUSIONS

One year after its application, EMD significantly improved PAL levels (1.1 mm) and PPD reduction (0.9 mm) when compared to a placebo or control, however, the high degree of heterogeneity observed among trials suggests that results have to be interpreted with great caution. In addition, a sensitivity analysis indicated that the overall treatment effect might be overestimated. The actual clinical advantages of using EMD are unknown. With the exception of significantly more postoperative complications in the GTR group, there was no evidence of clinically important differences between GTR and EMD. Bone substitutes may be associated with less REC than EMD.

A Comparative Study of Root Coverage Using Acellular Dermal Matrix With and Without Enamel Matrix Derivative

BACKGROUND

The aim of this study was to compare root coverage using acellular dermal matrix (ADM) with and without enamel matrix derivative (EMD) on the percentage of root coverage, probing attachment level, and the amount of keratinized tissue in the treatment of localized recession.

METHODS

Eighty-two contralateral sites in 14 patients with >or=2 mm of Miller Class I or III buccal tissue recession were treated. Forty-one test sites were treated with coronally advanced flap (CAF) using ADM in conjunction with EMD, whereas 41 control sites were treated with CAF using ADM alone. A split-mouth design was used for this study with 82 sites. Patients were followed for 3 and 6 months. A paired t test was conducted with the subject as the unit of analysis.

RESULTS

Based on paired t tests, both groups had significant improvement in the percentage of root coverage, probing attachment levels, and increased keratinized tissue. Only keratinized tissue in the test group demonstrated a statistically significant greater increase compared to controls at the 6-month evaluation (P = 0.006).

CONCLUSION

The use of EMD in conjunction with ADM resulted in a statistically significant effect on keratinized tissue increase, but no significant effects on probing attachment level or percentage of root surface coverage.

The application of an enamel matrix protein derivative (Emdogain) in regenerative periodontal therapy: a review

Regenerative periodontal therapy aims at reconstitution of the lost periodontal structures such as new formation of root cementum, periodontal ligament and alveolar bone. Findings from basic research indicate that enamel matrix protein derivative (EMD) has a key role in periodontal wound healing. Histological results from animal and human studies have shown that treatment with EMD promotes periodontal regeneration. Moreover, clinical studies have indicated that treatment with EMD positively influences periodontal wound healing in humans. This review aims to present an overview of evidence-based clinical indications for regenerative therapy with EMD.

The papilla amplification flap for the treatment of a localized periodontal defect associated with a palatal groove

BACKGROUND

Teeth with a palatal groove often present with severe localized periodontal attachment loss including pocket formation and alveolar bone loss. The aim of the present case report was to describe the regenerative surgical treatment of periodontal and bone lesions associated with the subgingival extension of a palatal groove affecting a maxillary lateral incisor.

METHODS

The left maxillary lateral incisor of a systemically healthy young subject presented with a palatal probing depth of 10 mm with no gingival recession at the buccal and palatal surfaces; the neighboring interdental papillae were intact. The radiograph showed a radiolucency area distal to the affected tooth. Treatment procedures consisted of: 1) the papilla amplification flap with the use of enamel matrix proteins as the regenerative periodontal material; 2) the elimination/flattening of the radicular portion of the palatal groove; and 3) the sealing of the coronal portion of the groove with composite flow.

RESULTS

The clinical examination at 1 year revealed a clinical attachment gain (8 mm) with a shallow residual probing depth (2 mm) and no increase in gingival recession. The radiographic examination showed the complete disappearance of the radiolucency area suggesting bone fill.

CONCLUSIONS

The present study indicated that localized periodontal defects associated with a palatal groove can be successfully treated by means of the papilla amplification flap with the use of enamel matrix protein as the regenerative material. The long-term stability of such successful results needs to be determined.

Treatment of Intrabony Defects With an Enamel Matrix Protein Derivative or Bioabsorbable Membrane: An 8-Year Follow-Up Split-Mouth Study

BACKGROUND

Treatments with either an enamel matrix protein derivative (EMD) or guided tissue regeneration (GTR) have been shown to promote periodontal regeneration. However, until recently, only limited data have been available on the long-term clinical results following these regenerative techniques. Therefore, the aim of this study was to present the 8-year results of a prospective, controlled, split-mouth clinical study evaluating the treatment of intrabony defects with EMD or GTR.

METHODS

Ten patients, each of whom displayed one pair of intrabony defects located contralaterally in the same jaw, were randomly treated with EMD or with GTR by means of bioabsorbable membranes. The following clinical parameters were evaluated at baseline and at 1 and 8 years after treatment: plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL). The primary outcome variable was CAL. No statistically significant differences between the groups were found at baseline.

RESULTS

The sites treated with EMD demonstrated a mean CAL change from 9.5 +/- 1.2 mm to 6.3 +/- 1.3 mm (P <0.001) and 6.7 +/- 1.6 mm (P <0.001) at 1 and 8 years, respectively. No statistically significant differences were found between the 1- and 8-year results. Sites treated with GTR showed a mean CAL change from 9.7 +/- 1.3 mm to 6.7 +/- 0.9 mm (P <0.001) at 1 year and 6.8 +/- 1.2 mm (P <0.001) at 8 years. The CAL change between 1 and 8 years did not present statistically significant differences. Between the treatment groups, no statistically significant differences in any of the investigated parameters were observed at 1 and at 8 years. However, the study does not have the statistical power to rule out the possibility of a difference between the two groups.

CONCLUSIONS

Within their limits, the present results indicate the following: 1) the clinical improvements obtained following treatment with EMD or GTR can be maintained over a period of 8 years; and 2) further studies of much higher power need to be performed to support equivalence.

Enamel matrix derivative alone or in combination with a bioactive glass in wide intrabony defects

This controlled clinical study investigated the clinical and radiographic outcome of wide intrabony periodontal defects treated by enamel matrix derivatives alone or in combination with a bioactive glass over a period of 8 months. Twenty-three chronic periodontitis patients, who received initial therapy and had radiographical interproximal defects with an associated probing depth of 6 mm or more and an intrabony component of at least 4 mm, were included. Each of the patients, contributing at least one intrabony defect, was treated with either enamel matrix derivative alone (group 1, n=10) or the combination (group 2, n=13). In both groups, all clinical and radiographical parameters were improved. Groups 1 and 2 presented a mean pocket reduction of 5.03+/-0.89 and 5.73+/-0.80 mm, recession of 0.97+/-0.24 and 0.56+/-0.18 mm, relative attachment gain of 4.06+/-1.06 and 5.17+/-0.85 mm, and radiographic bone gain of 2.15+/-0.42 and 2.76+/-0.69 mm, respectively. An intergroup comparison revealed significant differences for all of the parameters, yielding a more favorable outcome towards the combined approach. Within the limits of the study, both treatments resulted in marked clinical and radiographical improvements, but combined treatment seemed to enhance the results in the treatment of wide intrabony defects.

Enamel matrix derivative (Emdogain) for periodontal tissue regeneration in intrabony defects

BACKGROUND

Periodontitis is a chronic infective disease of the gums caused by bacteria present in dental plaque. This condition induces the breakdown of the tooth supporting apparatus until teeth are lost. Surgery may be indicated to arrest disease progression and regenerate lost tissues. Several surgical techniques have been developed to regenerate periodontal tissues including guided tissue regeneration (GTR), bone grafting (BG) and the use of enamel matrix derivative (EMD). EMD is an extract of enamel matrix and contains amelogenins of various molecular weights. Amelogenins are involved in the formation of enamel and periodontal attachment formation during tooth development.

OBJECTIVES

To test whether EMD is effective, and to compare EMD versus GTR, and various BG procedures for the treatment of intrabony defects.

SEARCH STRATEGY

We searched the Cochrane OHG Trials Register, Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE. Several journals were handsearched. No language restrictions were applied. Authors of RCTs identified, personal contacts and the manufacturer were contacted to identify unpublished trials. Most recent search: May 2005.

SELECTION CRITERIA

RCTs on patients affected by periodontitis having intrabony defects of at least 3 mm treated with EMD compared with open flap debridement, GTR and various BG procedures with at least 1 year follow up. The outcome measures considered were: tooth loss, changes in probing attachment levels (PAL), pocket depths (PPD), gingival recessions (REC), bone levels from the bottom of the defects on intraoral radiographs, aesthetics and adverse events. The following time-points were to be evaluated: 1, 5 and 10 years.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two authors. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CI). It was decided not to investigate heterogeneity, but a sensitivity analysis for the risk of bias of the trials was performed.

MAIN RESULTS

Ten trials were included out of 29 potentially eligible trials. No included trial presented data after 5 years of follow up, therefore all data refer to the 1-year time point. A meta-analysis including eight trials showed that EMD treated sites displayed statistically significant PAL improvements (mean difference 1.2 mm, 95% CI 0.7 to 1.7) and PPD reduction (0.8 mm, 95% CI 0.5 to 1.0) when compared to placebo or control treated sites, though a high degree of heterogeneity was found. Significantly more sites had < 2 mm PAL gain in the control group, with RR 0.48 (95% CI 0.29 to 0.80). Approximately six patients needed to be treated (NNT) to have one patient gaining 2 mm or more PAL over the control group, based on a prevalence in the control group of 35%. No differences in tooth loss or aesthetic appearance as judged by the patients were observed. When evaluating the only two trials at a low risk of bias in a sensitivity analysis, the effect size for PAL was 0.6 mm, which was less than 1.2 mm for the overall result. Comparing EMD with GTR (five trials), GTR showed a statistically significant increase of REC (0.4 mm) and significantly more postoperative complications. No trials were found comparing EMD with BG.

AUTHORS' CONCLUSIONS

One year after its application, EMD significantly improved PAL levels (1.2 mm) and PPD reduction (0.8 mm) when compared to a placebo or control, however, the high degree of heterogeneity observed among trials suggests that results have to be interpreted with great caution. In addition a sensitivity analyses indicated that the overall treatment effect might be overestimated. The actual clinical advantages of using EMD are unknown. With the exception of significantly more postoperative complications in the GTR group, there was no evidence of clinically important differences between GTR and EMD.

Enamel matrix proteins associated with GTR and bioactive glass in the treatment of class III furcation in dogs

This study investigated, both histologically and histometrically, the efficacy of enamel matrix derived proteins (EMD) associated with bioactive glass (BG) and an absorbable membrane in the treatment of class III furcation defects in mongrel dogs. After surgical defect creation and chronification, the lesions were randomly divided into three groups according to the treatment employed: Test Group 1 - EMD + BG + membrane, Test Group 2 - EMD + membrane and Control Group - BG + membrane. After a 90-day healing period, the dogs were sacrificed. The descriptive analysis and the histometric data showed similar results for the experimental groups in all studied parameters (MANOVA, p > 0.05). The association of Emdogain® with bioglass and GTR, or with GTR only, showed similar results when compared with the ones obtained with bioglass associated with membrane in the treatment of class III furcation defects in dogs. The three modalities of treatment showed partial filling of the furcations, with bone and cementum regeneration limited to the apical portion of the defects.

The combined use of enamel matrix proteins and a tetracycline-coated expanded polytetrafluoroethylene barrier membrane in the treatment of intra-osseous defects

OBJECTIVES

The purpose of this split-mouth study was to evaluate the clinical response of enamel matrix proteins (EMPs, Emdogain Gel in intra-osseous defects with or without a combined application of a tetracycline-coated expanded polytetrafluoroethylene barrier membrane (e-PTFE, Gore-Tex).

METHODS

Twelve pairs of intra-osseous periodontal defects in 11 patients received the application of EMPs on the exposed root surface (EMP). One of the two defects received randomly, as an adjunct to EMP treatment, a tetracycline-coated e-PTFE membrane (MEMP). At baseline, 6- and 12-month probing pocket depth (PPD), clinical attachment level (CAL) and probing bone level (PBL) were measured.

RESULTS

After 12 months, the EMP defects showed a significant mean PPD reduction of 2.86+/-0.75 mm, a mean gain in CAL of 1.28+/-2.04 mm, a mean PBL gain of 1.63+/-1.21 mm and a mean increase of recession (REC) of 1.56+/-2.30 mm. The MEMP defects showed a significant mean PPD reduction of 3.02+/-1.55 mm, a mean gain in CAL of 1.65+/-1.29 mm, a mean PBL gain of 1.58+/-1.92 mm and a mean increase of REC of 1.38+/-1.63 mm. Except for significantly more post-operative discomfort at the MEMP sites, no significant differences were found between EMP and MEMP defects.

CONCLUSION

Within the limits of this study, it is concluded that in the treatment of intra-osseous defects with EMP, the adjunctive use of a tetracycline-coated e-PTFE membrane failed to show more gain of CAL and PBL.

The Influence of Anatomical Features on the Outcome of Gingival Recessions Treated With Coronally Advanced Flap and Enamel Matrix Derivative: A 1-Year Prospective Study

BACKGROUND

Coronally advanced flap (CAF) is one of the most effective treatments of Miller Class I and II recessions. Even if excellent outcomes are reported in the literature, complete root coverage is not always predictable, since many surgical and host-related factors may affect the percentage of root coverage obtained. The aim of this clinical study was to evaluate if some anatomical features such as tissue thickness, papillae height and width, recession depth, and vestibular bone height may influence defect coverage of Miller Class I and II gingival recessions treated with CAF in combination with enamel matrix derivative (EMD).

METHODS

Thirty healthy, non-smoking patients (13 men and 17 women; mean age 32.8 +/- 6.2 years) were enrolled. Each patient was treated for one single recession using a CAF with the adjunct of EMD. Clinical parameters at baseline and 6 and 12 months were recorded and compared by using paired Student t test. Data were subdivided in two groups according to the baseline recession depth (REC): REC < 4 mm (group 1) and REC > or = 4 mm (group 2). The relation between the anatomical parameters (papilla height, papilla width, crestal bone height, and flap thickness) and percent of root coverage was evaluated by multiple linear regression analysis.

RESULTS

At 12 months, 91.7% of root coverage was obtained with a mean attachment gain of 3.23 mm. Better results in terms of percentage of root coverage were obtained when the baseline REC was < 4 mm compared to defects > or = 4 mm (96.5% versus 83.5%). Flap thickness was positively correlated to the percentage of root coverage. For gingival recessions > or = 4 mm, 100% root coverage was achieved only when tissue thickness was > or = 1 mm. Root coverage percentage was slightly related to papilla width in both groups, while it was associated with papilla height only in group 1 (P = 0.004). Only in patients in group 1 was the height of bone on the vestibular side related to the percentage of root coverage obtained (P = 0.003).

CONCLUSIONS

The results of the present study suggest that baseline recession depth and flap thickness may influence the outcome of marginal tissue recession therapy with CAF plus EMD at 12 months. There is not a clear relation between root coverage and other anatomical features as papilla width, papilla height, and the amount of bone on the vestibular side.

Alveolar ridge augmentation with a prototype trilayer membrane and various bone grafts: a histomorphometric study in baboons

Barrier membranes have become a standard treatment option in alveolar ridge augmentation prior to implant placement. However, non-resorbable membranes require secondary surgery and resorbable membranes show an unfavorable degradation profile. The purpose of this study was to evaluate the potential of a slowly biodegradable/bioresorbable prototype trilayer membrane (PTLM) for supporting bone regeneration in alveolar ridge augmentation. Clinically relevant cavities were made 3 months after the extraction of the first and second molars in each jaw of six baboons. Each animal was treated with four different regimens: (1) autogenous bone block (ABB) alone, (2) ABB+PTLM, (3) deproteinized bovine bone mineral (DBBM)+PTLM and (4) no treatment. After 9 months, the baboons were sacrificed and block sections of the augmented area were subjected to histologic and histomorphometric analyses. Newly formed bone areas were determined at a distance of 1, 3, 7 and 10 mm from crestal. The data showed a well-preserved ridge profile at the membrane-protected sites, whereas non-protected bone blocks and control sites underwent severe resorption resulting in knife-edge ridge profiles. Significant differences were found between ABB+PTLM and ABB (P=0.0137-0.0232). DBBM+PTLM also produced a larger bone area compared with ABB alone (P=0.0396-0.0439). No significant difference in bone area was detectable between ABB+PTLM and DBBM+PTLM (P>0.05). The present study supports the use of the slowly biodegradable/bioresorbable PTLM with autografts and DBBM for lateral ridge augmentation in this type of bone defects.

Healing of human intrabony defects following regenerative periodontal therapy with an enamel matrix protein derivative alone or combined with a bioactive glass. A controlled clinical study

AIM

The purpose of the present study was to compare clinically the treatment of deep intrabony defects with a combination of an enamel matrix protein derivative (EMD) and a bioactive glass (BG) to EMD alone.

METHODS

Thirty patients (16 females and 14 males) suffering from advanced marginal periodontitis were included in this prospective, controlled parallel design multicenter study. In each of the patients, one intrabony defect was randomly treated with either EMD+BG (test) or with EMD alone (control). Clinical measurements were recorded at baseline and at 1 year following therapy.

RESULTS

No differences in any of the investigated parameters were observed at baseline between the two groups. Healing was uneventful in all patients. At 1 year after therapy, the test group showed a reduction in mean probing depth (PD) from 8.5+/-1.1 to 4.4+/-1.2 mm (p<0.001) and a change in mean clinical attachment level (CAL) from 10.4+/-1.5 to 7.1+/-1.5 mm (p<0.0001). In the control group, the mean PD was reduced from 8.5+/-1.5 to 4.0+/-1.6 mm (p<0.001) and the mean CAL changed from 10.2+/-2.1 to 6.3+/-2.2 mm (p<0.01). In the test group, 12 sites (80%) gained at least 3 mm or more of CAL, whereas in the control group a CAL gain of 3 mm or more was measured at 13 sites (87%). No statistically significant differences in terms of PD reduction and CAL gain were found between the test and the control treatment.

CONCLUSIONS

Within the limits of the present study it can be concluded that: (i) at 1 year after surgery, both therapies resulted in significant PD reductions and CAL gains, and (ii) the combination of EMD+BG does not seem to additionally improve the clinical results.

Effect of Enamel Matrix Derivative on Collagen Guided Tissue Regeneration-Based Root Coverage Procedure

BACKGROUND

Enamel matrix derivative (EMD) has been shown to promote periodontal wound healing and/or regeneration when applied to tooth root surfaces in soft tissue dehiscence models. In addition, guided tissue regeneration (GTR)-based root coverage using collagen membrane (GTRC) has shown promising results. However, limited information is available regarding how EMD may influence GTRC outcome.

METHODS

Twenty-six patients with Miller's Class I or II gingival recession defects of 2.5 mm were recruited for the study. Subjects were randomly assigned to receive either EMD + collagen (EMDC; test group) or collagen membrane (GTRC; control group). Clinical parameters, including plaque index (PI), gingival index (GI), relative clinical attachment levels (RCAL) to the stent, recession depth (RD), recession width (RW), probing depth (PD), gingival tissue thickness (GTT), and width of keratinized gingiva (KG) were assessed at baseline, and 3 and 6 months after surgery. A repeated measure of analysis of variance (ANOVA) was used to determine differences between treatment groups and time effect.

RESULTS

Both treatments (GTRC and EMDC) resulted in a statistically significant decrease in RD and RW between baseline and 6 months (P <0.05). However, no difference was noted between treatment groups. The percent of root coverage after 6 months was 75% for GTRC and 63% for EMDC. Complete 100% root coverage was achieved in five patients in the GTRC group, compared to only one patient in the EMDC group. There was a statistically significant gain (P <0.05) in the clinical attachment level (CAL) between baseline and 6 months in both groups, as reflected on the RCAL data. No other significant differences were noted on other clinical parameters (PD, GTT, KG, GI, and PI).

CONCLUSIONS

GTR-based root coverage utilizing collagen membrane, with or without enamel matrix derivative, can be successfully used in obtaining gingival recession coverage. The application of EMD during GTRC procedures did not add additional benefit to the final clinical outcome.

The use of enamel matrix derivative in the treatment of periodontal defects: a literature review and meta-analysis

BACKGROUND

Periodontal disease results in the loss of the attachment apparatus. In the last three decades, an increasing effort has been placed on seeking procedures and materials to promote the regeneration of this tissue. The aim of this paper is to evaluate the effect of enamel matrix derivative (EMD) during regenerative procedures. In addition, a meta-analysis is presented regarding the clinical results during regeneration with EMD, to gain evidence as to what can be accomplished following treatment of intrabony defects with EMD in terms of probing depth reduction, clinical attachment level gain, defect fill (using re-entry studies), and radiographic parameters.

METHODS

The review includes in vitro and in vivo studies as well as human case reports, clinical comparative trials, and histologic findings. In addition, a meta-analysis is presented regarding the regenerative clinical results. For this purpose, we used 28 studies-including 955 intrabony defects treated with EMD that presented baseline and final data on probing depth, clinical attachment level (CAL) gain, or bone gain-to calculate weighted mean changes in the different parameters. The selected studies were pooled from the MEDLINE database at the end of May, 2003.

RESULTS

The meta-analysis of intrabony defects treated with EMD resulted in a mean initial probing depth of 7.94 +/- 0.05 mm that was reduced to 3.63 +/- 0.04 mm (p = 0.000). The mean clinical attachment level changed from 9.4 +/- 0.06 mm to 5.82 +/- 0.07 mm (p = 0.000). These results were significantly better than the results obtained for either open-flap debridement (OFD) or guided tissue regeneration (GTR). In contrast, histologically, GTR is more predictable than EMD in terms of bone and cementum formation. No advantage was found for combining EMD and GTR. Xenograft, or EMD and xenograft, yielded inferior results compared with EMD alone, but a limited number of studies evaluated this issue. Promising results were noted for the combination of allograft materials and EMD.

CONCLUSIONS

EMD seems to be safe, was able to regenerate lost periodontal tissues in previously diseased sites based on clinical parameters, and was better than OFD or GTR. Its combination with allograft materials may be of additional benefit but still needs to be further investigated.

Clinical Evaluation of Demineralized Freeze-Dried Bone Allograft and Enamel Matrix Derivative Versus Enamel Matrix Derivative Alone for the Treatment of Periodontal Osseous Defects in Humans

BACKGROUND

A recent study suggests that the addition of enamel matrix derivative to demineralized freeze-dried bone allograft may enhance osseoinduction. The purpose of this study was to evaluate the use of demineralized freeze-dried bone allograft (DFDBA) in combination with enamel matrix derivative (EMD + DFDBA) compared to enamel matrix derivative (EMD) alone in the treatment of human intrabony periodontal defects.

METHODS

Forty patients with a total of 67 sites (intrabony defect > or = 3 mm deep) were selected to participate in this single-masked, parallel design, randomized, controlled clinical trial. Each subject received either EMD alone (34 sites) or in combination with DFDBA (33 sites). Soft tissue measurements included probing depth (PD), clinical attachment level (CAL), and recession. Hard tissue measurements included defect depth, alveolar crestal resorption, and defect morphology. Following 6 months of healing, all soft tissue measurements were repeated. Forty-nine sites (EMD + DFDBA = 26 sites, EMD alone = 23 sites) were surgically reentered. Statistical analyses were performed using unpaired and paired Student t tests.

RESULTS

Analyses showed a significant improvement in soft tissue parameters for both treatment groups (P < 0.001) as compared to preoperative measurements. There were no statistical differences between treatment groups. The probing depth reduction (PDR) for the EMD + DFDBA was 3.6 +/- 0.2 mm, while the EMD alone had a PDR of 4.0 +/- 0.3 mm. The CAL gain for the EMD + DFDBA group was 3.0 +/- 0.3 mm and 3.2 +/- 0.3 mm for the EMD alone group. The mean value for bone fill in the EMD + DFDBA group was 3.7 +/- 0.2 mm (74.9%), while the EMD alone group demonstrated a mean bone fill of 2.6 +/- 0.4 mm (55.3%). While there were no significant differences between the two treatments with regards to soft tissue measurements, the combination of EMD + DFDBA therapy yielded statistically significant improvements in bone fill, crestal resorption, and percentage of sites gaining greater than 50% and 90% bone fill when compared to EMD alone (P < 0.001).

CONCLUSION

The results of this study indicate that there may be an enhancement of hard tissue parameters when enamel matrix derivative is added to demineralized freeze-dried bone allograft.

A Randomized Clinical Trial Comparing Enamel Matrix Derivative and Membrane Treatment of Buccal Class II Furcation Involvement in Mandibular Molars. Part I: Study Design and Results for Primary Outcomes

BACKGROUND

The objective of this multicenter, randomized trial was to compare enamel matrix derivative (EMD; test) with barrier membranes (control) for the treatment of mandibular buccal Class II furcation defects.

METHODS

Forty-five patients with 90 comparable defects on contralateral molars were included. Defects were randomly assigned to EMD or bioabsorbable barrier membrane; the contralateral defect received the alternative treatment. Assessments at baseline and 8 and 14 months included gingival margin levels, probing depths, bleeding on probing, vertical attachment levels, and vertical bone sounding from a stent at five buccal sites/ tooth. Defect dimensions were recorded at surgery and during reentry at 14 months. Change of open horizontal furcation depth was the primary outcome variable. Adverse reactions and patient perceptions were also noted.

RESULTS

Both treatment modalities led to significant clinical improvements. The median reduction of open horizontal furcation depth was 2.8 mm with the corresponding interquartile interval (1.5 mm, 3.5 mm) at test sites compared with 1.8 mm (1.0 mm, 2.8 mm) at control sites. The Hodges-Lehmann estimator of the advantage (reduction test versus control) was 0.75 mm (95% confidence interval [CI]: 0.125 mm, 1.375 mm, P = 0.033, Wilcoxon). The frequency of complete furcation closure was 8/45 (test) and 3/45 (control); partial closure, 27/45 in both groups; no change, 9/45 and 11/45, respectively; and deterioration, 1/45 and 4/45, respectively. The frequency of no pain or no swelling at 1 week post-surgery was 62% and 44%, respectively, at the test sites and 12% and 6% at the control sites.

CONCLUSION

There was a significantly greater reduction in horizontal furcation depth and a comparatively lower incidence of postoperative pain/swelling following enamel matrix derivative compared to membrane therapy.

Five-year results following treatment of intrabony defects with enamel matrix proteins and guided tissue regeneration

BACKGROUND

Treatment with enamel matrix proteins (EMD) or guided tissue regeneration (GTR) has been shown to enhance periodontal regeneration. However, until now there are limited data on the long-term results following these treatment modalities.

AIM

The aim of the present clinical study was to present the 5-year results following treatment of intrabony defects with EMD, GTR, combination of EMD and GTR, and open flap debridement (OFD).

MATERIAL AND METHODS

Forty-two patients, each of whom displayed one intrabony defect of a probing depth of at least 6 mm, were randomly treated with one of the four treatment modalities. The following parameters were evaluated prior to surgery, at 1 year and at 5 years after: plaque index, gingival index, bleeding on probing, probing pocket depth (PPD), gingival recession, and clinical attachment level (CAL). No statistically significant differences in any of the parameters were observed at baseline between the four groups.

RESULTS

The sites treated with EMD demonstrated a mean CAL gain of 3.4+/-1.1 mm (p<0.001) and of 2.9+/-1.6 mm (p<0.001) at 1 and 5 years, respectively. The sites treated with GTR showed a mean CAL gain of 3.2+/-0.8 (p<0.001) at 1 year and of 2.7+/-0.9 mm (p<0.001) at 5 years. The mean CAL gain at sites treated with EMD+GTR was 3.0+/-1.0 mm (p<0.001) and 2.6+/-0.7 mm (p<0.001) at 1 and 5 years, respectively. The sites treated with OFD demonstrated a mean CAL gain of 1.6+/-1.0 mm (p<0.001) at 1 year and 1.3+/-1.2 mm (p<0.001) at 5 years. At 1 year, the only statistically significant difference between the four different treatments was found in terms of PPD reduction and CAL gain between EMD and OFD (p<0.05). However, at 5 years there were no statistically significant differences in any of the investigated parameters between the four different treatments.

CONCLUSION

Within the limits of the present study, it may be concluded that the short-term clinical results following treatment with EMD, GTR, EMD+GTR, and OFD can be maintained over a period of 5 years.

A Multicenter Study Evaluating the Sensitization Potential of Enamel Matrix Derivative After Treatment of Two Infrabony Defects

BACKGROUND

Several studies reported some success toward regeneration in infrabony defects using enamel matrix derivative (EMD). Clinically and statistically significant improvements in probing depth reduction, clinical attachment levels, and bone fill have been demonstrated. This multi-center study evaluated the potential for sensitization to EMD in a subgroup of periodontal patients treated at least twice with at least 2 months between treatments.

METHODS

Three hundred seventy-six (376) patients in 11 university-based postgraduate periodontics programs and five private practices were selected. Surgeries were performed on infrabony defects. Following reflection of mucoperiosteal flaps and debridement of the root surface and defect, root conditioning (either citric acid pH = 1 or 24% EDTA) was performed and the site was irrigated with sterile saline. Enamel matrix derivative was reconstituted and applied to the exposed root surface and the bony defect. Flaps were sutured and pressure applied for 5 minutes. The second test defect was treated in a similar manner at least 8 weeks after the first surgery. The patient was given a diary card where any subjective adverse events (erythema, swelling, itching, headache, root hypersensitivity, or pain) were recorded at weeks 1 and 2 post-surgery. In addition, objective adverse events (gingival inflammation, ulcers, abscess, cratering, and lesions) were recorded by the investigator on an adverse event form.

RESULTS

No clinical adverse reactions to multiple applications of EMD were noted. Of 376 patients, two were referred to a dermatologist for evaluation, but neither had signs indicating any adverse events due to EMD treatment. Instead their reactions were classified as a small local abscess and tinea cruris. The single immunoassay performed (on the patient with a small local abscess) did not demonstrate any EMD-reactive antibodies, neither IgE nor IgG. Other subjective/objective reactions that occurred during this study were of the type that are commonly experienced by patients immediately following periodontal surgery, but were not related to EMD. They included headache, swelling, itching, pain, and root hypersensitivity.

CONCLUSIONS

This study demonstrated a lack of clinical adverse reactions following two separate applications of EMD. Any subjective/objective adverse reactions experienced by the patient were typical complications following routine periodontal surgery and were not directly related to the use of enamel matrix derivative.

Removal of Epithelium in Periodontal Pockets following Diode (980 nm) Laser Application in the Animal Model: Anin VitroStudy

OBJECTIVE

The purpose of this study was to examine the removal of the epithelium in the periodontal pocket using a diode (980 nm) laser in comparison with the conventional techniques in an animal experimental model.

BACKGROUND DATA

The goal of periodontal therapy is to reduce the bacterial deposits in the pockets and to enhance the clinical attachment. Different surgical techniques have been used in the past, which control the epithelial migration and promote the connective tissue formation.

MATERIALS AND METHODS

The buccal pockets of the posterior teeth in 10 freshly sacrificed adult pigs were scaled by three different examiners (with different levels of experience in periodontal surgery) using conventional curettes. The lingual pockets were treated using a diode (980 nm) laser. The laser was used in a continuous wave (c. w.) mode with two different power settings (2 and 4 Watts) with a 300-microm-thick glass fiber. The instrumentation period revealed 15 sec in all of the sites. Soft tissue biopsies of the instrumented sites were removed and examined histologically.

RESULTS

In all of the lased sections, no epithelial remnants were found. The laser with a low power was able to remove the thin pocket epithelium in the same way regardless of the level of surgical experience of the examiner. A high-power setting presented significant damage to the underlying connective tissues. The sites, which were instrumented with the conventional curettes, demonstrated significant epithelial remnants in all of the tissues regardless of the level of periodontal surgical experience.

CONCLUSION

The histological findings presented in this study showed that instrumentation of the soft periodontal tissues with a diode laser (980 nm) leads to a complete epithelial removal in comparison to conventional treatment methods with hand instruments (independent of the clinician's experience).

Enamel matrix proteins in the treatment of intra-bony defects. A prospective 24-month clinical trial

BACKGROUND

A growing flow of recent evidence indicates enamel matrix derivative (EMD, Emdogain) as a useful tool for the regeneration of periodontal tissues. This prospective clinical study aimed to evaluate the efficacy of EMD combined with surgical treatment of periodontal intra-bony defects, as compared with surgery alone, up to 24 months of follow-up.

METHODS

Twenty-four intra-bony defects were treated in 24 patients in a single clinical centre. Each defect had intra-bony depth (IBD) > or = 4 mm and probing pocket depth (PPD) > or = 6 mm. Patients were randomly assigned to either test or control group. Plaque index (PI), gingival index (GI), PPD and periodontal attachment level (PAL) were assessed at baseline pre-surgical examination at the site to be treated. Full mouth plaque score (FMPS) and full mouth bleeding score (FMBS) were also evaluated. Twelve patients were treated by simplified papilla preservation flap technique (control group), while 12 patients were treated with the same surgical technique plus EMD after ethylenediamine tetraacetic acid root conditioning (test group). Any probing at the involved sites was avoided in the first year post-surgery. Radiographs were taken at baseline, 12 and 24 months after surgery using customized bite blocks. Intra-bony defect depth (IBD) and angle (IBA) were measured from X-rays by a computer-aided technique. At 12 and 24 months post-surgery, FMPS, FMBS, PI, GI, PPD, PAL and radiographic IBD and IBA were assessed. The difference between each follow-up and baseline, and between groups at each follow-up was evaluated for the above parameters by standard statistical methods.

RESULTS

In both groups, clinical and radiographic parameters were improved at either 12 or 24 months when compared with baseline. The test group displayed better outcomes when compared with the control group for IBD, PPD, and PAL gain at 12 months, and only for PAL and IBD gain at 24 months. No adverse event related to the use of EMD was reported.

CONCLUSIONS

The surgical procedure used in the present study, aiming for maximum preservation of the regenerative potential of periodontal tissues, showed per se excellent results. The use of EMD as an adjunct to periodontal surgery in the treatment of angular defects possibly enhances periodontal regeneration rate.

Growth and Amelogenin-Like Factors in Periodontal Wound Healing. A Systematic Review

BACKGROUND

Regeneration of tooth-supporting structures destroyed by periodontitis is a major goal of periodontal therapy. Periodontal tissue engineering utilizing growth and amelogenin-like factors (GAFs) applies advances in materials science and biology to regenerate alveolar bone, periodontal ligament, and cementum. Amelogenin-like factors (e.g., enamel matrix derivative [EMD]) and growth factors (e.g., platelet-derived growth factor [PDGF] and bone morphogenetic proteins [BMPs, also considered morphogens]) have demonstrated pleotrophic effects on the stimulation of several key events required for tissue regeneration including DNA synthesis, chemotaxis, differentiation, and matrix synthesis.

RATIONALE

GAFs have been used for the treatment of periodontal disease as shown in preclinical and clinical studies. This systematic review evaluates the evidence to support the utilization of EMD and growth factors (GFs) for periodontal repair and regeneration associated with natural teeth.

FOCUSED QUESTION

In patients with periodontal osseous defects, what is the effect of GAFs compared with controls on clinical, radiographic, histologic, adverse, and patient-centered outcomes?

SEARCH PROTOCOL

Two investigators searched MEDLINE, pre-MEDLINE, and the Cochrane Oral Health Group trials register for clinical and preclinical studies published in English. Hand searches were performed on the International Journal of Periodontics and Restorative Dentistry, Journal of Clinical Periodontology, Journal of Dental Research, Journal of Periodontology, and Journal of Periodontal Research. Searches were performed for articles published through April 2002. In addition, investigators contacted manufacturers of GAF products for related unpublished data and studies in progress.

SELECTION CRITERIA

INCLUSION CRITERIA

Randomized controlled clinical trials (RCTs), cohort studies, case-control studies, case reports, and preclinical (animal) randomized controlled investigations that included a cohort population diagnosed with periodontal disease and presenting data on intrabony/interproximal defects and/or furcation defects were screened.

EXCLUSION CRITERIA

In vitro studies or those that did not include quantifiable data with respect to clinical or bone measures were not included.

DATA COLLECTION AND ANALYSIS

Meta-analyses were performed for studies that fulfilled the eligibility criteria for the following continuous variables: clinical attachment level (CAL), probing depth (PD), or bone level (radiographic, re-entry, or histologic). Heterogeneity was assessed to determine whether the differences among therapies were due to systematic confounding factors (as noted in study quality assessments).

MAIN RESULTS

1. Eight studies, representing 7 RCTs and 1 quasi-experimental study, representing a total population of 511 subjects were analyzed with respect to EMD. 2. The majority of the remaining papers had a low evidence rating. 3. Most reports were case studies or case series without controls. 4. There were insufficient data to conduct a meta-analysis on the effect of growth factors used in periodontal repair around teeth.

REVIEWERS' CONCLUSIONS

1. There is evidence supporting the use of EMD for periodontal osseous defects to improve CAL and reduce PD, although long-term benefits have not been established. 2. EMD has demonstrated notable consistency among the studies investigated in terms of superiority to controls (in general compared to open flap debridement [OFD]). 3. EMD appears to be safe for single and multiple administrations in terms of lack of elicitation of antibody responses or other local/systemic inflammatory events. 4. Preclinical and initial clinical data for growth factors appear promising but are insufficient to draw definitive conclusions at this time.

Wound healing of degree III furcation involvements following guided tissue regeneration and/or Emdogain®

BACKGROUND

The use of enamel matrix proteins (EMD) has been recently introduced as a new treatment alternative for periodontal regeneration. However, no histological studies are available investigating the effect of EMD in the treatment of degree III furcation involvements.

OBJECTIVES

The aim of this study was to evaluate the healing of mandibular degree III furcation involvements histologically following treatment with guided tissue regeneration (GTR), EMD and a combination of EMD and GTR.

MATERIAL AND METHODS

Degree III furcation involvements were surgically created at the teeth 36, 37, 46, 47 in three monkeys (Macaca fascicularis). Spontaneous healing of the defects was prevented by placing impression material into the defects. After 6 weeks, full-thickness flaps were elevated at the buccal and lingual aspect of the experimental teeth. Following removal of all granulation tissue from the furcation defects, scaling/root planing and conditioning of the root surfaces with 24% EDTA gel, the defects were treated with one of the following treatment modalities: (i) EMD, (ii) GTR or (iii) a combination of EMD and GTR. The defects serving as control did not receive any treatment, except from complete coverage with coronally displaced flaps. After 5 months of healing, the animals were killed and perfused with 10% buffered formalin for fixation. The experimental teeth with surrounding tissues were dissected free, decalcified in EDTA, dehydrated and embedded in paraffin. 8 microm thick histological sections were cut and stained and subsequently examined under the light microscope.

RESULTS

The histological analysis revealed that with GTR or combined EMD and GTR treatment, new attachment formation (new cementum with inserting collagen fibers) had occurred on almost the entire circumference of the furcation and new bone was almost filling the defect in the situations where the membrane was not exposed. The sites treated only with EMD exhibited new attachment and new bone formation to a varying extent, while the control sites presented only limited new attachment and bone formation.

CONCLUSION

The results provided histological evidence suggesting that both GTR and EMD may result in true periodontal regeneration, and suggest that this type of healing might be favored by such treatments in comparison with flap surgery.

Effect of enamel matrix proteins (Emdogain® ) on healing after re-implantation of “periodontally compromised” roots

OBJECTIVE

The present experiment was performed to assess whether Emdogain applied on the root surface of extracted teeth or teeth previously exposed to root planning can protect the tooth from ankylosis following re-implantation.

MATERIAL AND METHODS

The experiment included two groups of dogs, including five animals each. The root canals of all mandibular third premolars (3 P 3) were reamed and filled with gutta-percha. A crestal incision was placed from the area of the second to the fourth premolar. Buccal and lingual full thickness flaps were elevated. With the use of a fissure bur, the crown and furcation area of 3 P 3 were severed in an apico-coronal cut. The distal and mesial tooth segments were luxated with an elevator and extracted with forceps. Group A: The mesial and distal segments of 3 P 3 were air dried on a glass surface for 60 min. The roots from the right side were conditioned and exposed to Emdogain application. The roots from the left side received the same treatment with the exception of Emdogain application. The mesial and distal tooth segments were re-implanted and the crown portions were severed with a horizontal cut and removed. The buccal and lingual flaps were mobilized and sutured to obtain complete coverage of the submerged roots. Group B: A notch was prepared in each root, 4-5 mm apical of the cemento-enamel junction. The area of the root that was located coronal to the notch was scaled and planned. The roots in the right side of the mandible were treated with Emdogain, while the roots in the left side served as controls. After 6 months of healing, the dogs were killed and blocks containing one root with surrounding tissues were harvested, and prepared for histological examination, which also included morphometric assessments. Thus, the proportions of the roots that exhibited signs of (i) replacement (ii) inflammatory and (iii) surface resorption were calculated.

RESULTS AND CONCLUSION

It was demonstrated that healing of a re-implanted root that had been extracted and deprived of vital cementoblasts was characterized by processes that included root resorption, ankylosis and new attachment formation. It was also demonstrated that Emdogain treatment, i.e. conditioning with EDTA and placement of enamel matrix proteins on the detached root surface, failed to interfere with the healing process.