Guided Tissue Regeneration With Bioabsorbable Barriers. II. Long-Term Results in Infrabony Defects

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

BACKGROUND

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

AIM

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

MATERIAL & METHODS

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

RESULTS

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

CONCLUSION

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

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

CLINICAL RELEVANCE

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

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

AIM

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Five-year stability of clinical attachment after regenerative treatment of infrabony defects compared to controls

AIM

To evaluate the stability of attachment achieved in infrabony defects by regenerative treatment over 60 ± 12 months compared to control teeth.

METHODS

Patients treated regeneratively in at least one infrabony defect between 2004 and 2010 were screened for this retrospective cohort study. Complete examinations available for baseline, 12 and 60 ± 12 months after surgery, and a respective control tooth without treatment, provided eligibility for analysis.

RESULTS

Twenty-seven patients (age 58 ± 11.7 years; 12 females, five smokers) were included, each contributing one infrabony defect and one control tooth. Regenerative therapy resulted in significant attachment gain (2.7 ± 1.6 mm; p < 0.001) after 1 and (3.0 ± 2.2 mm; p < 0.001) 5 years. Control teeth were stable (vertical probing attachment level [PAL-V] change: 1 year: 0 ± 0.8 mm; 5 years: -0.2 ± 1.2 mm). The study did not detect any significant change of PAL-V from 1 to 5 years after surgery for regenerative (-0.3 ± 2.4 mm) and control teeth (-0.2 ± 1.4 mm). Multivariate analysis associated smoking and generalized recurrence of periodontitis (amount of sites with PPD > 5 mm) with attachment loss.

CONCLUSIONS

PAL-V achieved by regenerative therapy in infrabony defects is as stable over 5 years as periodontally reduced but gingivally healthy or gingivitis sites. Smoking and periodontitis recurrence are associated with attachment loss.

Differential benefits of amoxicillin-metronidazole in different phases of periodontal therapy in a randomized controlled crossover clinical trial

BACKGROUND

The specific advantage of administering systemic antibiotics during initial, non-surgical therapy or in the context of periodontal surgery is unclear. This study assesses the differential outcomes of periodontal therapy supplemented with amoxicillin-metronidazole during either the non-surgical or the surgical treatment phase.

METHODS

This is a single-center, randomized placebo-controlled crossover clinical trial with a 1-year follow-up. Eighty participants with Aggregatibacter actinomycetemcomitans-associated moderate to advanced periodontitis were randomized into two treatment groups: group A, antibiotics (500 mg metronidazole plus 375 mg amoxicillin three times per day for 7 days) during the first, non-surgical phase of periodontal therapy (T1) and placebo during the second, surgical phase (T2); and group B, placebo during T1 and antibiotics during T2. The number of sites with probing depth (PD) >4 mm and bleeding on probing (BOP) per patient was the primary outcome.

RESULTS

A total of 11,212 sites were clinically monitored on 1,870 teeth. T1 with antibiotics decreased the number of sites with PD >4 mm and BOP per patient significantly more than without (group A: from 34.5 to 5.7, 84%; group B: from 28.7 to 8.7, 70%; P <0.01). Twenty patients treated with antibiotics, but only eight treated with placebo, achieved a 10-fold reduction of diseased sites (P = 0.007). Consequently, fewer patients of group A needed additional therapy, the mean number of surgical interventions was lower, and treatment time in T2 was shorter. Six months after T2, the mean number of residual pockets (group A: 2.8 ± 5.2; group B: 2.2 ± 5.0) was not significantly different and was sustained over 12 months in both groups.

CONCLUSION

Giving the antibiotics during T1 or T2 yielded similar long-term outcomes, but antibiotics in T1 resolved the disease quicker and thus reduced the need for additional surgical intervention.

Surgical guided tissue regeneration treatment of advanced periodontal defects: a 5-year follow-up study

OBJECTIVES

To study the 5-year outcome of combined use of guided tissue regeneration (GTR) barriers and bovine bone in advanced periodontal defects.

MATERIAL AND METHODS

In each of 24 patients, one defect was surgically exposed, debrided, filled with bovine bone, and covered with a bioresorbable barrier. Re-examinations were made after 1, 3, and 5 years.

RESULTS

Average full-mouth plaque scores (FMPS) were 14.5% at baseline and 10.7%, 9.8%, and 18.9% after 1, 3, and 5 years, respectively. Mean probing pocket depth (PPD) was 10.0 mm at baseline. Mean PPD reduction was 5.2 mm after 1 year, 5.6 mm after 3 years, and 5.3 mm after 5 years. Mean gingival recession was 1.0 mm after 1 year, 1.6 mm after 3 years, and 1.3 mm after 5 years. Mean gain in clinical attachment level (CAL) was 4.2 mm at the 1-year, 4.1 mm at the 3-year, and 4.3 mm at the 5-year examination. Smoking significantly influenced CAL change at all re-examinations. FMPS were significantly correlated with radiographic defect depth at the 5-year examination and CAL with smoking and FMPS at the 3-year examination.

CONCLUSION

Advanced periodontal defects can be successfully treated with the combined use of GTR barriers and bovine bone to substantially reduce PPD and achieve a stable, long-term gain of CAL.

Stability of Clinical and Radiographic Results After Guided Tissue Regeneration in Infrabony Defects

BACKGROUND

The aim of this 5-year follow-up study was to evaluate clinically and radiographically the long-term results after guided tissue regeneration (GTR) therapy of infrabony defects using non-resorbable and bioabsorbable barriers.

METHODS

Thirty-one patients with periodontitis and 50 infrabony defects that had been treated using GTR were recruited. Eleven defects were treated with non-resorbable expanded polytetrafluoroethylene membranes and 39 defects with bioabsorbable barriers. At baseline and 6 and 60 +/- 3 months after surgery, clinical parameters and standardized radiographs were obtained. During surgery and 60 +/- 3 months thereafter, the distance from the cemento-enamel junction to the base of the bony defect (vertical probing bone level [PBL-V]) was measured. Bone gain was evaluated using digital subtraction radiography.

RESULTS

At 6 and 60 +/- 3 months after GTR, there was a statistically significant (P <0.001) reduction of probing depth (6 months: 4.31 +/- 1.76 mm; 60 months: 3.95 +/- 1.62 mm) and vertical clinical attachment level gains (CAL-V) (6 months: 3.34 +/- 1.66 mm; 60 months: 2.97 +/- 1.53 mm). From 6 to 60 months after GTR, three infrabony defects exhibited CAL-V loss >2 mm, and a small, statistically not significant mean CAL-V loss of 0.39 +/- 1.60 mm was observed. From baseline to 60 +/- 3 months, a significant PBL-V gain of 1.78 +/- 2.67 mm (P <0.001) and increase in bone density were observed (P = 0.003).

CONCLUSION

The CAL-V gain achieved after GTR in infrabony defects using both non-resorbable and bioabsorbable barriers was stable after 5 years in 47 of 50 defects.

Influence of autologous platelet concentrate on healing in intra-bony defects following guided tissue regeneration therapy: a randomized prospective clinical split-mouth study

OBJECTIVES

To investigate the influence of autologous platelet concentrate (APC) on early wound healing and regeneration outcomes following guided tissue regeneration (GTR) therapy.

MATERIAL AND METHODS

In 25 patients, two contralateral deep intra-bony defects were treated with beta-TCP and a bioresorbable GTR membrane. They were randomly assigned to test and control procedure. In test defects, APC was additionally applied. After 3, 6, and 12 months, healing results were assessed by clinical parameters and quantitative digital subtraction radiography.

RESULTS

Post-operative membrane exposures occurred in 48% of the test sites and 80% of the control sites. Both groups revealed a significant clinical attachment level (CAL) gain of 5 mm after 12 months. Eighty-eight per cent of test and control sites showed a CAL gain of > or =4 mm. No clinical parameter revealed significant differences between test and control sites. A significant bone density gain was found in both groups after 3, 6, and 12 months. Only after 6 months, the bone density gain was significantly greater in the test defects.

CONCLUSION

Within the limits of this study, autologous platelet concentrate did not seem to have a noticeable influence on the clinical and most of the radiographic outcomes following GTR. However, APC might reduce the occurrence of post-operative membrane exposures and accelerate bone density gain.

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.

Bioabsorbable Membrane and Bioactive Glass in the Treatment of Intrabony Defects in Patients With Generalized Aggressive Periodontitis: Results of a 5-Year Clinical and Radiological Study

BACKGROUND

The aim of this clinical and radiological prospective 5-year study was to compare the long-term effectiveness of a bioabsorbable membrane and a bioactive glass in the treatment of intrabony defects in patients with generalized aggressive periodontitis.

METHODS

Sixteen patients (11 women and five men) with generalized aggressive periodontitis were enrolled in the study. The investigations were confined to 1- to 3-walled intrabony defects with a depth >/=4 mm and with preoperative probing depths (PDs) >/=7 mm. Teeth with furcation involvement were excluded. Twenty-two of the defects were treated with the membrane (RXT group) and 20 with the bioactive glass (PG group). Allocation to the two groups was randomized. The clinical parameters plaque index (PI), gingival index (GI), PD, bleeding on probing (BOP), gingival recession (GR), clinical attachment level (CAL), and tooth mobility were recorded before surgery and at 6 months and every year for 5 years after surgery. Intraoral radiographs were taken using a standardized paralleling technique at baseline and every year for 5 years. Statistical analysis was based on Kolmogorov-Smirnov and Wilcoxon signed-rank tests, analysis of covariance, and Spearman's bivariate correlation analysis.

RESULTS

After 5 years, a reduction in PD of 3.6 +/- 0.8 mm (P = 0.016) and a gain in CAL of 3.0 +/- 2.0 mm (P = 0.01) were registered in the RXT group. There was a slight increase in GR by 0.6 +/- 1.4 mm (P = 0.334). In the PG group, a reduction in PD of 3.5 +/- 1.4 mm (P = 0.01) and a gain in CAL of 3.3 +/- 2.1 mm (P = 0.01) were recorded, whereas GR increased by 0.2 +/- 1.7 mm (P = 0.525). The 1-, 2-, 3-, and 4-year results did not differ significantly from the 5-year results. Radiographically, the defects (the point on the proximal surface of the defective tooth at which the projected alveolar crest intersected the root surface [xCA] to the most coronally located point at the proximal surface of the tooth on the defect side up to which the periodontal ligament space still displayed a uniform width [xBD]) were found to be filled by 47.5% +/- 38.3% (P = 0.001) in the RXT group and by 65.0% +/- 50.5% (P = 0.001) in the PG group. Crestal resorption (the most apical point of the enamel at the proximal surface of the tooth on the defect side [xCEJ] to the xCA) was 19.0% +/- 30.2% (P = 0.374) in the RXT group and 12.3% +/- 38.6% (P = 0.647) in the PG group. The xCEJ to the xBD was significantly more in the PG group (28.4 +/- 24.6 versus 7.3 +/- 21.8, P = 0.048). A good standard of oral hygiene and inflammation-free periodontal tissue in the postoperative phase improved the treatment outcome. No dependence of attachment gain was found on the tooth type, number of walls involved in the defects (r = 0.075; P = 0.319), or intraoperative depth (r = 0.114; P = 0.307).

CONCLUSIONS

Highly significant improvements in the parameters PD and CAL were recorded after 5 years with both regenerative materials. Radiographically, the defects (the xCED to the xBD) were found to be filled significantly more in the bioactive glass group. A good standard of oral hygiene and inflammation-free periodontal tissue in the postoperative phase improved the treatment outcome.

An Alveolar Bone Augmentation Technique to Improve Esthetics in Anterior Ceramic FPDs: A Clinical Report

This clinical report describes guided bone augmentation for treatment of a facial maxillary alveolar bone defect to enhance the esthetic result for an all-ceramic fixed partial denture (FPD). A combination of decalcified freeze dried bone allograft and resorbable human pericardium, in conjunction with cortical channel expansion, was used for the augmentation process to eliminate a secondary surgical procedure. Post-operative examinations showed improvement in the alveolar bone contour. The regeneration of the missing osseous structure was accomplished to support the future esthetic soft tissue contours. This osseous regenerative technique significantly increased the functional and esthetic outcome of the final FPD by restoring the alveolar ridge defect to its original dimension.