Osseous autografts. III. Comparison of osseous coagulum-bone blend implants with open curetage

Comparision of crosslinked hyaluronic acid vs. enamel matrix derivative for periodontal regeneration: an 18-month follow-up randomized clinical trial

AIM

To compare the effects of 1.8% hyaluronic acid (HA) and enamel matrix derivative (EMD) on periodontal regeneration in patients with periodontal bone defects, using clinical and radiographic parameters as outcome measures.

MATERIALS AND METHODS

We included 53 patients with 53 intrabony defects in this study who were randomly assigned to either the HA (test) or EMD (control) groups. Clinical and radiographic parameters were evaluated at 6, 12, and 18 months after the surgery.

RESULTS

Clinical measurements at 6, 12, and 18 months after surgery demonstrated significant improvements in probing depth (PD), clinical attachment level (CAL), recession (REC), and bleeding on probing for both groups compared with baseline (p < 0.001). The EMD group exhibited the highest CAL gain of 2-3 mm at 6 months, observed in 14 of 26 (53.8%) defect sites. Conversely, the HA group demonstrated a CAL gain ≥ 4 mm at 18 months, observed in 13 of 27 (48.1%) defect sites. Radiographic assessments at 6, 12, and 18 months demonstrated significant improvements from baseline for both groups (p < 0.001).

CONCLUSION

We found significant clinical and radiographic benefits of HA and EMD at 18 months, with some limitations in effectiveness for specific intraosseous defects.

CLINICAL RELEVANCE

This study demonstrated that hyaluronic acid (HA), combined with minimally invasive techniques, enhances periodontal regeneration by improving PPD reduction, CAL gain, and radiographic bone filling, with cost-effectiveness, application, and bioavailability surpassing that of other biomaterials. Based on these results, HA can be considered a viable alternative to EMD in indicated cases.

CLINICAL TRIAL REGISTRATION NUMBER

clinicalTrial.gov - NCT04274244.

Regenerative periodontal therapy: I part

Introduction: Under the concept of regenerative periodontal therapy, there are two approaches: the first is the passive regeneration conceptthat includes bone substituents and guided periodontal regeneration by using of biomembranes and the second concept of active regeneration that impliesthe use of growth factors. The aim of the passive regeneration, by using of bone matrix (bone substituens) has been stabilization and bone defects management, preventing epithelial tissue growth, as well as saving space for the new tissue regeneration. This concept implies the use of autogenous transplantats, xenografts, allografts, as well as alloplastic materials. The carriers for active tissue regeneration, growth factors -GF are biological mediators that regulate cellular processes and that is crucial for the tissue regeneration. Aim:Presentation ofmodern approaches to periodontal therapy thatare focused on the attachment regeneration and complete reconstruction of periodontal tissue. Conclusion: In the future, periodontal regenerative therapy with periodontalligament progenitor cells should encourage repopulation of the areas that have been affected by periodontal disease.

Clinical evaluation of a biphasic calcium phosphate grafting material in the treatment of human periodontal intrabony defects

Purpose

The aim of this study was to compare the clinical outcome of open flap debridement (OFD) with a biphasic calcium phosphate (BCP) graft to that of OFD without BCP graft for the treatment of intrabony periodontal defects (IBDs).

Methods

The study included 25 subjects that had at least one intrabony defect of 2- or 3-wall morphology and an intrabony component≥4 mm as detected radiographically. Subjects were randomly assigned to treatment with (BCP group, n=14) or without BCP (OFD group, n=11). Clinical parameters were recorded at baseline and 6 months after surgery and included the plaque index, gingival index, probing depth (PD), clinical attachment level (CAL), and gingival recession (REC). A stringent plaque control regimen was enforced for all of the patients during the 6-month observation period.

Results

In all of the treatment groups, significant PD reductions and CAL gains occurred during the study period (P<0.01). At 6 months, patients in the BCP group exhibited a mean PD reduction of 3.7±1.2 mm and a mean CAL gain of 3.0±1.1 mm compared to the baseline. Corresponding values for the patients treated with OFD were 2.5±0.8 mm and 1.4±1.0 mm, respectively. Compared to OFD group, the additional CAL gain was significantly greater in the patients in BCP group (P=0.028). The additional PD reduction was significant for the BCP group (P=0.048). The REC showed a significant increase in both groups, and the amount of recession was significantly smaller in the BCP group than OFD group (P=0.023). In radiographic evaluation, the height of the bone fill in the BCP group was significantly greater than OFD group.

Conclusions

The clinical benefits of BCP found in this study indicate that BCP may be an appropriate alternative to conventional graft materials.

Management of infrabony defects in mandibular molars in a patient with generalized aggressive periodontitis using autogenous bone graft from maxillary tuberosity

This clinical case report presents a technique utilizing autogenous cancellous bone from maxillary tuberosity to fill two infrabony defects distal to mandibular molars in a patient diagnosed with aggressive periodontitis. After debridement a 6 mm defect was present distal to mandibular right first molar and 6.5 mm defect was present distal to mandibular second molar of same side. Autogenous bone graft from maxillary tuberosity was placed in both the defects. There was a significant bony fill present six months post surgery and probing depth reduced by 7mm on both the sites.

A Clinical Comparison of Cenobone (A Decalcified Freeze-dried Bone Allograft) with Autogenous Bone Graft in the Treatment of Two- and Three-wall Intrabony Periodontal Defects: A Human Study with Six-month Reentry

Background and aims

Complete and predictable regeneration of tissue lost as a result of infection or trauma is the ultimate goal of periodontal therapy. Various graft materials have been successfully used in the treatment of intrabony defects. The purpose of this study was to evaluate the use of a decalcified freeze-dried bone allograft (Cerabone) with the autogenous bone graft as a gold standard in the treatment of human two- or three-wall intrabony periodontal defects.

Materials and methods

This split-mouth study was done on 10 pairs of matched two- or three-wall intrabony periodontal defects with 5 mm or more probing depth and 3 mm or more depth of intrabony component following phase I therapy. In the control sites autogenous bone graft and in the test sites decalcified freeze-dried bone allograft were used.

Results

At baseline, no significant differences were found in terms of oral hygiene and defect charac-teristics. At six months, analysis showed a significant improvement in soft and hard tissue parameters for both treatment groups as compared to preoperative measurements. There were no statistical differ-ences in clinically-measured parameters between treatment groups after 6 months except for crestal resorption that increased significantly in control group (P = 0.25). Defect resolution and bone fill in the test and control groups were 2.5 ± 0.46 mm versus 2.7 ± 0.73 mm and 2 ± 0.62 mm versus 2.20 ± 0.52 mm, respectively.

Conclusion

The results of this study demonstrated that both graft materials improved clinical parameters. The comparison of the two treatment groups did not show any significant differences in clinical parameters after six months. However, because of the limited amount of intra-oral donor bone, it is preferable to use decalcified freeze-dried bone allograft.

Bone replacement grafts for the treatment of periodontal intrabony defects

Bone replacement grafts, including autogenous grafts from intraoral donor sites, allografts, xenografts, and alloplastic bone substitutes, are the most widely used treatment modalities for the regeneration of periodontal osseous defects. Studies suggest a favorable clinical outcome with the use of these materials in terms of improvements in periodontal probing depths, probing attachment gains, and bone fill. In terms of bone fill, most studies report more than 50% resolution of intrabony defects when treated with bone replacement grafts. However, histologic evidence of periodontal regeneration, including new bone, periodontal ligament, and cementum, has been reported only for autogenous bone grafts and demineralized freeze-dried bone allografts.

Position Paper: Periodontal Regeneration

Untreated periodontal disease leads to tooth loss through destruction of the attachment apparatus and tooth-supporting structures. The goals of periodontal therapy include not only the arrest of periodontal disease progression,but also the regeneration of structures lost to disease where appropriate. Conventional surgical approaches (e.g., flap debridement) continue to offer time-tested and reliable methods to access root surfaces,reduce periodontal pockets, and attain improved periodontal form/architecture. However, these techniques offer only limited potential towards recovering tissues destroyed during earlier disease phases. Recently, surgical procedures aimed at greater and more predictable regeneration of periodontal tissues and functional attachment close to their original level have been developed, analyzed, and employed in clinical practice. This paper provides a review of the current understanding of the mechanisms, cells, and factors required for regeneration of the periodontium and of procedures used to restore periodontal tissues around natural teeth. Targeted audiences for this paper are periodontists and/or researchers with an interest in improving the predictability of regenerative procedures. This paper replaces the version published in 1993.

Periodontal regeneration techniques for treatment of periodontal diseases

The ultimate goal of periodontal therapy is the regeneration of structures lost to disease. Conventional surgical approaches such as open-flap debridement offer only limited regeneration potential.Currently, surgical procedures for predictable regeneration of periodontal tissues are being developed, analyzed, and employed in clinical practice. This article addresses current trends in periodontal regeneration. Various materials/agents such as bone replacement grafts, barrier membranes, and biologic modifiers currently used for the regeneration of periodontal infrabony and furcation defects are discussed.

The efficacy of bone replacement grafts in the treatment of periodontal osseous defects. A systematic review

BACKGROUND

Bone replacement grafts (BRG) are widely used in the treatment of periodontal osseous defects; however, the clinical benefits of this therapeutic practice require further clarification through a systematic review of randomized controlled studies.

RATIONALE

The purpose of this systematic review is to access the efficacy of bone replacement grafts in proving demonstrable clinical improvements in periodontal osseous defects compared to surgical debridement alone.

FOCUSED QUESTION

What is the effect of bone replacement grafts compared to other interventions on clinical, radiographic, adverse, and patient-centered outcomes in patients with periodontal osseous defects?

SEARCH PROTOCOL

The computerized bibliographical databases MEDLINE and EMBASE were searched from 1966 and 1974, respectively, to October 2002 for randomized controlled studies in which bone replacement grafts were compared to other surgical interventions in the treatment of periodontal osseous defects. The search strategy included screening of review articles and reference lists of retrieved articles as well as hand searches of selected journals.

INCLUSION CRITERIA

All searches were limited to human studies in English language publications.

EXCLUSION CRITERIA

Non-randomized observational studies (e.g., case reports, case series), publications providing summary statistics without variance estimates or data to permit computation, and studies without BRG intervention alone were excluded.

DATA COLLECTION AND ANALYSIS

The therapeutic endpoints examined included changes in bone level, clinical attachment level, probing depth, gingival recession, and crestal resorption. For purposes of meta-analysis, change in bone level (bone fill) was used as the primary outcome measure, measured upon surgical re-entry or transgingival probing (sounding).

MAIN RESULTS

1. Forty-nine controlled studies met eligibility criteria and provided clinical outcome data on intrabony defects following grafting procedures. 2. Seventeen studies provided clinical outcome data on BRG materials for the treatment of furcation defects.

REVIEWERS' CONCLUSIONS

1. With respect to the treatment of intrabony defects, the results of meta-analysis supported the following conclusions: 1) bone grafts increase bone level, reduce crestal bone loss, increase clinical attachment level, and reduce probing depth compared to open flap debridement (OFD) procedures; 2) No differences in clinical outcome measures emerge between particulate bone allograft and calcium phosphate (hydroxyapatite) ceramic grafts; and 3) bone grafts in combination with barrier membranes increase clinical attachment level and reduce probing depth compared to graft alone. 2. With respect to the treatment of furcation defects, 15 controlled studies provided data on clinical outcomes. Insufficient studies of comparable design were available to submit data to meta-analysis. Nonetheless, outcome data from these studies generally indicated positive clinical benefits with the use of grafts in the treatment of Class II furcations. 3. With respect to histological outcome parameters, 2 randomized controlled studies provide evidence that demineralized freeze-dried bone allograft (DFDBA) supports the formation of a new attachment apparatus in intrabony defects, whereas OFD results in periodontal repair characterized primarily by the formation of a long junctional epithelial attachment. Multiple observational studies provide consistent histological evidence that autogenous and demineralized allogeneic bone grafts support the formation of new attachment. Limited data also suggest that xenogenic bone grafts can support the formation of a new attachment apparatus. In contrast, essentially all available data indicate that alloplastic grafts support periodontal repair rather than regeneration. 4. The results of this systematic review indicate that bone replacement grafts provide demonstrable clinical improvements in periodontal osseous defects compared to surgical debridement alone.

Periodontal Regeneration with a Combination of Enamel Matrix Proteins and Autogenous Bone Grafting

BACKGROUND

Attempts to stimulate periodontal regeneration in the past have focused on either filling the defect with some type of material or providing a space for host cells to repopulate the site and elicit new tissue. In some cases, these approaches have been combined with the assumption that the filler material will help maintain the space necessary for the host cells to invade the area. Growth stimulating substances such as growth factors and other proteins have also been used to encourage periodontal tissue regeneration and histological evaluation supports the use of these substances. Thus, the role for and the necessity of a certain amount of space maintenance for periodontal regeneration is not exactly understood. In addition, it is not known if there is some critical size required for space maintenance or for exactly how long the space must be maintained in order for the host cells to stimulate new cementum, periodontal ligament, and bone. The goal of this study was to evaluate periodontal regeneration in intrabony defects of various sizes treated with a combination of enamel matrix proteins and autogenous bone graft.

METHODS

Periodontal defects ranging in size from 1 to 6 mm were randomized and created bilaterally beside three teeth in the mandibles of baboons. Plaque was allowed to accumulate around wire ligatures placed into the defects. After 2 months, the wire ligatures were removed, the teeth and roots scaled and root planed, and a notch was placed with a chisel at the base of the defect. On one side of the mandible, neutral ethylene diamine tetracetic acid and enamel matrix derivative (EMD) were first used to treat the defect. Autogenous bone taken from the same surgical site was treated with enamel matrix derivative in a dampen dish and then added to the EMD-treated defects. The other side of the mandible served as control with neutral ethylene diamine tetracetic acid and scaling and root planing. Flaps were sutured and the animals were allowed to heal without oral hygiene procedures. After 5 months, the animals were sacrificed and the teeth were processed for histological evaluation.

RESULTS

The results revealed new cementum, periodontal ligament with Sharpey's fibers, and new bone tissue similar to native periodontal tissues. Remnants of the autogenous bone chips were still present at this 5-month post-healing period. Thus periodontal regeneration occurred in all sizes of the periodontal defects. In general, EMD plus autogenous graft treatment resulted in greater tissue formation than controls. In fact, in many cases, very dramatic tissue formation occurred far coronal to the base of the defects in the EMD plus autogenous graft-treated lesions. In addition, horizontal bone fill occurred in the defects and was prominent in the 4 or 6 mm wide lesions. When evaluating the combined 1 and 2 mm defects, the height of new cementum with EMD plus graft was 3.88 mm versus 2.03 mm in the controls, a statistically significant (P < 0.005) difference. In the wider (4 and 6 mm) lesions, this difference was not significant and was much less between treated and control lesions with 2.78 and 2.57 mm of new cementum respectively. In the case of new bone height, in the smaller lesions EMD plus graft resulted in 4.00 mm new bone versus 2.22 mm in the controls, again a statistically significant (P < 0.005) difference. In the larger lesions, EMD plus autogenous bone graft had 3.24 mm new bone height compared to 2.71 mm in the controls, a difference that was not statistically significant. Additionally, in the smaller lesions, new cementum width at the level of the notch was twice as great (statistically significant, P < 0.015) in the EMD plus graft sites compared to control. The width of the periodontal ligament at the coronal aspect of the new bone tissue was similar in the smaller lesions between treated and control sites. The results from the wider defects must be interpreted cautiously as the interproximal bone heights were remodeled adjacent to the wider defects and likely limited the potential for regeneration.

CONCLUSIONS

The combination of enamel matrix derivative plus autogenous bone graft stimulated statistically significant periodontal regeneration in the more narrow 1 and 2 mm lesions. No statistically significant difference was observed in the wider 4 and 6 mm lesions. In many cases, dramatic amounts of new cementum, Sharpey's fibers, periodontal ligament, and bone tissue were formed far above the notch placed at the base of the contaminated defects. This was especially significant considering the width of some of the defects and the fact that no oral hygiene was performed over the 5-month healing period. This periodontal regeneration occurred in the absence of exogenous growth factors or barrier membranes. In summary, the combination of enamel matrix derivative and autogenous bone represents a therapeutic combination that can be highly effective in stimulating significant amounts of periodontal regeneration.

Effects of Low-Dose Cyclosporin on Osteogenesis of Human Demineralized Bone Grafts in a Surgically Created Mandibular Defect in Rats

BACKGROUND

Demineralized freeze-dried bone matrix (DFDBM) stimulates new bone formation; however, immune reactions from the residual antigens of prepared grafts might play a role in inducing osteogenesis. This study examined whether cyclosporine-A (CsA), an immunosuppressant, enhanced the DFDBM-induced new bone formation.

METHODS

After creating a bony defect in the posterior mandible, 40 male Sprague-Dawley rats were divided into four groups of 10 each: no graft with mineral oil (control); no graft with CsA in mineral oil; DFDBM with mineral oil; and DFDBM with CsA in mineral oil (combined therapy). CsA was administered at 2 mg/kg body weight. Five rats in each group were sacrificed at days 10 and 28 and tissue samples were taken for histological examination.

RESULTS

Soft tissue was observed in the defects of all animals without grafts, whereas the repaired hard tissue formed in the defects of animals with grafts. Histometery, which was performed only at day 10, revealed both DFDBM and CsA therapies produced a significant increase in the total area of repaired hard tissue. Only CsA therapy significantly increased the new bone area. Compared with the DFDBM group, the composition of the repaired hard tissue in the combined therapy group shifted; i.e., the new bone area increased but the residual particle area decreased. The cartilage formation was greater in the combined therapy group than the DFDBM group.

CONCLUSION

Within the limitations of this study, we suggest that the DFDBM grafts play a major role, which could be enhanced by CsA, in the induction of new bone formation, especially at an early phase.

A systematic review of graft materials and biological agents for periodontal intraosseous defects

OBJECTIVES

To determine the adjunctive effect of grafting biomaterials/biological agents with open flap debridement (OFD) in the treatment of deep intraosseous defects.

BACKGROUND

No systematic review of treatment outcomes in patients who received graft biomaterials or biological agents have been published.

METHODS

A rigorous systematic review of randomized controlled trials of at least 6-month duration was conducted comparing grafting biomaterials/biological agents (alone or in combination) + OFD (test group) to OFD alone or in combination with a placebo (control group).

RESULTS

The difference in CAL change between test and control groups varied from -1.45 mm to 1.40 mm with respect to different biomaterials/biological agents. Meta-analysis showed that CAL change significantly improved after treatment for coralline calcium carbonate (weighted mean difference 0.90 mm; 95% CI: 0.53-1.27), bioactive glass (weighted mean difference 1.04 mm; 95% CI: 0.31-1.76), hydroxyapatite (weighted mean difference 1.40 mm, 95% CI 0.64-2.16), and enamel matrix proteins (weighted mean difference 1.33 mm, 95% CI 0.78-1.88). However, heterogeneity in results between studies was highly statistically significant for most of biomaterials/biologicals and could not be fully explained.

CONCLUSIONS

Overall, the use of specific biomaterials/biologicals was more effective than OFD in improving attachment levels in intraosseous defects. Difference in CAL gain varied greatly with respect to different biomaterial/biological agent. Due to a significant heterogeneity in results between studies in most treatment groups, general conclusions about the expected clinical benefit of graft biomaterials/biologicals need to be interpreted with caution. Further research should focus on understanding this variability.

Defect-determined regenerative options for treating periodontal intrabony defects in baboons

BACKGROUND

In an effort to regenerate periodontal intrabony defects, the healing potential of the defect should determine what therapeutic modalities and materials are employed. The purpose of this study was to compare regenerative outcomes in baboon intrabony defects that were contained versus non-contained, using various regenerative therapies.

METHODS

Nine adult baboons (Papio anubis) in good health were treated. Eighty-six interproximal, intrabony defects were surgically created: 43 contained by 3 walls of bone; 43 non-contained with a missing buccal wall. Chronicity and plaque accumulation were encouraged with wire ligature placement for 8 weeks. After ligature removal, scaling, and a 2- to 4-week healing period, the defects were treated with the following therapies: collagen membrane (GTR), human demineralized freeze-dried bone (DFDB) grafting (BG), combined therapy (GTR + BG) and a DFDB-glycoprotein sponge matrix (MAT). Clinical healing responses were evaluated in 58 sites by changes in soft tissue (recession, probing, clinical attachment) and hard tissue (resorption, defect fill) parameters 6 months post-treatment. Histologic evaluation (defect regeneration, connective tissue attachment, epithelial migration) was done on 26 sites.

RESULTS

For contained defects, no real significant clinical (ANOVA) or histologic differences existed among treatments. However, for non-contained defects, combined therapy (GTR + BG) demonstrated clinically significant (P < or = 0.05, ANOVA) and histologically superior healing results over the other therapies tested.

CONCLUSION

These results confirm a defect morphology directed rationale for periodontal intrabony therapy.

Distraction osteogenesis and histogenesis in beagle dogs: the effect of gradual mandibular osteodistraction on bone and gingiva

BACKGROUND

No study has systematically evaluated the effect of distraction osteogenesis on the gingival tissues. Therefore, this study was designed to analyze the newly formed bone and gingiva during the consolidation period of mandibular osteodistraction using standard histologic techniques.

METHODS

Seventeen skeletally mature male beagle dogs underwent 10 mm of bilateral interdental mandibular lengthening. After distraction, the regenerates were allowed to consolidate for 0, 2, 4, 6, or 8 weeks, then the animals were sacrificed and tissues harvested for analysis.

RESULTS

Mineralization began at the host bone margins at the end of the distraction period, followed by a progressive increase in bone surface area, with a concomitant decrease in fibrous tissue. The gingiva initially underwent mild inflammatory and reactive changes during distraction and during the first few weeks of consolidation. The rate of bone formation gradually increased from the end of distraction to the fourth week of consolidation, at which time it remained constant until sometime before the eighth week, when it tapered off slightly as remodeling began. From the second through the eighth week of consolidation, regenerative changes and neohistogenesis were seen in the gingival tissues.

CONCLUSIONS

Osteodistraction has the potential to drastically decrease the total treatment time for alveolar bone augmentation prior to dentoalveolar implant placement since the regenerate bone rapidly mineralizes within approximately 8 to 10 weeks after the distraction period and the gingiva responds favorably to increased length by regeneration rather than by degeneration. Although the results appear favorable, similar data should be evaluated in human clinical trials.

The effectiveness of enamel matrix proteins used in combination with bovine porous bone mineral in the treatment of intrabony defects in humans

OBJECTIVE

The purpose of this study was to evaluate the effectiveness of enamel matrix proteins (EMPs) used in combination with bovine porous bone mineral (BPBM), compared to open flap debridement (OFD) in the treatment of intrabony defects in humans.

MATERIAL AND METHODS

Using a split-mouth design, 24 paired intrabony defects were surgically treated and re-entered 6 months later. Experimental sites were treated with EMPs and grafted with BPBM. Control sites were treated with an OFD. The primary outcomes evaluated in the study were changes in pocket depth, clinical attachment level and defect bone fill.

RESULTS

Preoperative pocket depths, attachment levels and intra-operative bone measurements were similar for control and experimental sites. 6-month post surgical measurements revealed a significantly greater reduction in pocket depth (differences of 2.35+/-0.86 mm on buccal and 2.28+/-0.90 mm on lingual measurements) and more gain in clinical attachment (differences of 2.04+/-0.28 mm on buccal and 1.99+/-0.26 mm on lingual measurements) in the experimental sites. Surgical reentry of the defects revealed a significantly greater amount of defect fill in favor of the experimental sites (differences of 2.85+/-0.28 mm on buccal and 2.67+/-0.33 mm on lingual measurements).

CONCLUSIONS

The results of this study suggest that combining EMPs and BPBM as a regenerative technique for intraosseous defects results in statistically and clinically significant more favorable results than OFD. The nature of the attachment between the newly regenerated tissue and the root surfaces needs to be evaluated histologically to confirm the presence of new attachment.

Bioactive glass granules for regeneration of human periodontal defects

PURPOSE

A comparative study which evaluated the effectiveness of bioactive glass granules of uniform size (300-335 microns) for the regenerative treatment of interproximal intrabony periodontal defects was conducted.

MATERIALS AND METHODS

Twelve pairs of advanced periodontal lesions in 12 patients (6 males and 6 females) were treated in a split-mouth design with open flap débridement in the control sites and open flap débridement with bioactive glass particles placed in the test sites.

RESULTS

At 6 months post-treatment, both treatment modalities demonstrated a gain in clinical attachment level (CAL), with the test sites having a significantly (p < .01) greater gain in CAL than the control sites. Reentry procedures were performed to assess the amount of hard tissue fill. The test sites demonstrated significantly (p < .001) more gain in hard tissue fill than the controls.

Specific issues in clinical trials on the use of barrier membranes in periodontal regeneration

There are presently a number of different barriers available for use clinically in guided tissue regeneration (GTR) procedures. A number of trials using these techniques and comparing different types of barrier membranes are being published in the scientific literature. This review discusses issues related to clinical trials on the use of barrier membranes in periodontal regeneration. Outcome measures, both clinical and histological, are discussed in relation to results following GTR procedures. The difference between regeneration and repair is reviewed as well as methods of clinical and histologic assessment of both these outcomes. Data regarding the impact of patient variables and tooth or defect variables on outcomes are presented and suggestions for study designs are made based on these variables. Aspects of assessing for an appropriate sample size in superiority and equivalency trials using GTR techniques are presented as well as interpretation of results following these trials and their clinical significance.

Periodontal regeneration around natural teeth

1. Evidence is conclusive (Table 2) that periodontal regeneration in humans is possible following the use of bone grafts, guided tissue regeneration procedures, both without and in combination with bone grafts, and root demineralization procedures. 2. Clinically guided tissue regeneration procedures have demonstrated significant positive clinical change beyond that achieved with debridement alone in treating mandibular and maxillary (buccal only) Class II furcations. Similar data exist for intraosseous defects. Evidence suggests that the use of bone grafts or GTR procedures produce equal clinical benefit in treating intraosseous defects. Further research is necessary to evaluate GTR procedures compared to, or combined with, bone grafts in treating intraosseous defects. 3. Although there are some data suggesting hopeful results in Class II furcations, the clinical advantage of procedures combining present regenerative techniques remains to be demonstrated. Additional randomized controlled trials with sufficient power are needed to demonstrate the potential usefulness of these techniques. 4. Outcomes following regenerative attempts remain somewhat variable with differences in results between studies and individual subjects. Some of this variability is likely patient related in terms of compliance with plaque control and maintenance procedures, as well as personal habits; e.g., smoking. Variations in the defects selected for study may also affect predictability of outcomes along with other factors. 5. There is evidence to suggest that present regenerative techniques lead to significant amounts of regeneration at localized sites on specific teeth. However, if complete regeneration is to become a reality, additional stimuli to enhance the regenerative process are likely needed. Perhaps this will be accomplished in the future, with combined procedures that include appropriate polypeptide growth factors or tissue factors to provide additional stimulus.

Bone allografts in periodontal therapy

Bone allografts as used in dentistry have a 20-year history of safety and efficacy. Case reports and controlled clinical trials have shown the potential of both mineralized and decalcified cortical freeze-dried bone allograft to reconstruct the bone defects caused by periodontitis. Histomorphometric analysis of human biopsies following grafts of decalcified freeze-dried bone allograft have shown the ability of decalcified freeze-dried bone allograft to promote regeneration of new bone, cementum, and periodontal ligament on a tooth root surface previously exposed to bacterial plaque. The addition of mineralized freeze-dried bone allograft and decalcified freeze-dried bone allograft to the guided tissue and guided bone regeneration procedures have significantly enhanced results, especially in large osseous lesions.

The modified papilla preservation technique. A new surgical approach for interproximal regenerative procedures

A modification of the papilla preservation technique has been applied to achieve primary closure of the interproximal tissue over barrier membranes placed coronal to the alveolar crest. Fifteen patients with deep intrabony interproximal defects were treated. Defects had a probing attachment level loss of 9.9 +/- 3.2 mm and a recession of the gingival margin of 1.7 +/- 1.6 mm. The depth of the intrabony component was 5.5 +/- 2.9 mm; while the suprabony component was 5.9 +/- 2.0 mm. Titanium-reinforced teflon membranes were placed 1.3 +/- 0.7 mm from the cemento-enamel junction, 4.5 +/- 1.6 mm coronal to the interproximal alveolar bone crest. Primary closure over the interproximal portion of the membrane was obtained in 93% of cases. In 73% of the cases complete coverage of the membrane was maintained until its removal at 6 weeks. These data indicate that the modified papilla preservation technique can be successfully applied to obtain primary closure of the interdental space in regenerative procedures with barrier membranes.

Mandibular cementifying fibroma in relation to a large periodontal bone defect. Report of a case

A cementifying fibroma associated with a large intraosseous periodontal defect is reported. This tumor was located in the lingual aspect of the first lower left molar. Therapy consisted on flap surgery, tumor excision, and placement of a bone autograft in order to fill the residual bone defect. Six months after the treatment, clinical and radiographic signs of periodontal regeneration were evidenced.

Phenotypic characterization of mononuclear cells following anorganic bovine bone implantation in rats

The purpose of this study was to measure inflammatory changes associated with implantation of anorganic bovine bone and bovine bone/collagen composite grafts, and to compare the response to that obtained following grafting with hydroxyapatite. Anorganic bovine bone, either with or without bovine collagen, as well as granular and block forms of synthetic hydroxyapatite, were implanted subcutaneously in Wistar rats. Saline and turpentine oil were used as controls. Biopsies were obtained after 3 days and at 1, 2, 4, 6, and 8 weeks. A panel of 6 monoclonal antibodies was used to detect monocytes, several distinct macrophage subsets, Ia-antigen expression, and T- and B-lymphocytes. Cells identified by each antibody were counted after immunocytochemical staining, and sera obtained 6 weeks after grafting were used in immunoblotting assays to detect antibodies to bovine serum proteins and collagen. Anorganic bovine bone, bovine bone/collagen, and hydroxyapatite all produced a transient macrophage infiltrate that was maximum 3 days after implantation, but resolved to normal levels within 6 to 8 weeks. Lymphocyte infiltration was not elicited by any bovine graft material, and antibodies to bovine serum proteins or type I collagen were not detected in any of the animals examined. These data indicate that a systemic or local immune response does not develop following implantation with anorganic bovine bone or with anorganic bovine bone/collagen materials. It appears appropriate to explore further the merits of these materials for periodontal regenerative procedures.

Clinical evaluation of coralline calcium carbonate as a bone replacement graft material in human periodontal osseous defects

A resorbable coralline calcium carbonate graft material (CalCarb) was compared to open flap debridement (DEBR) in human periodontal osseous defects. Following appropriate initial preparation procedures, flap surgery with defect and root debridement was performed in 20 patients. Alternating defects in each segment of surgery were treated with each procedure. Appropriate periodontal maintenance schedules were followed, and at 6 to 12 months a re-entry flap surgery was performed for documentation and finalization of treatment. Forty defects which received CalCarb grafts demonstrated significantly better mean defect fill of 2.3 mm (67.7%) versus a mean defect fill of 0.7 mm (25.9%) (P < 0.01) for 39 defects treated with DEBR. Other hard tissue findings showed similar clinically superior results with the use of CalCarb. Relative defect fill results showed 88% positive (50% to 100% defect fill) responses with CalCarb and only 13% positive responses with DEBR. There were 7 times more failures (minimal response) with DEBR than with CalCarb. Soft tissue findings showed no significant differences between treatments. These results are similar to those with other synthetic and natural bone replacement graft materials. However, the ease of handling of the CalCarb material, its resorbability, and its potential for improved bone regeneration may be of clinical advantage.

Guided tissue regeneration and bone grafts in the treatment of furcation defects

The present study evaluated the effects of guided tissue regeneration (GTR), with and without demineralized freeze-dried cortical bone grafts, in the treatment of furcation defects in 4 female beagle dogs with naturally occurring periodontal disease. The root surfaces were thoroughly debrided. Four weeks later, full thickness facial and lingual mucoperiosteal flaps were reflected using inverse bevel incisions on both sides of the mandible involving the 2nd, 3rd, and 4th premolar, and the 1st molar teeth. Following debridement, notches were placed on the roots at the level of supporting bone. Test quadrants were randomly selected and furcations were filled with reconstituted, demineralized, freeze-dried human cortical bone grafts. Following bone grafting, all defects were covered with an expanded polytetrafluoroethylene (ePTFE) membrane, which was sutured with 4-0 sutures. Afterward, interproximal sutures were placed through the flaps, assuring the flaps covered the membranes completely. The contralateral side, serving as control, was treated by debridement only and application of ePTFE membrane. All membranes were removed 6 weeks after surgery. Dogs were sacrificed at 4 months after surgery. Both mesio-distal and bucco-lingual histologic sections were evaluated by descriptive histology. Linear measurements and surface area determination of the furcal tissues were carried out using the microscope attached to a digitizer. Twelve to 20 nonserial sections were made of the mid-buccal aspects of each root of each treated tooth. Half of these sections were stained with Harris' hematoxylin and eosin (H&E) and the other half stained with Mallory's trichrome stain.(ABSTRACT TRUNCATED AT 250 WORDS)

Cryopreserved cancellous bone allograft in periodontal intraosseous defects

The purpose of this study was to evaluate the potential of cryopreserved cancellous bone allograft (CCBA) in the treatment of intraosseous periodontal defects compared to surgical debridement alone (DEBR). Cancellous bone was procured from femur heads that had been extracted for hip prosthesis procedures and cryopreserved in liquid nitrogen (-196 degrees C) in a tissue bank. Ten patients without systemic disorders and advanced periodontal disease (at least 2 intraosseous defects) participated in this investigation. Measurements from the cemento-enamel junction were made after initial therapy for clinical attachment level; also gingival recession, probing pocket depth, plaque index, and gingival index and, at the time of surgery, alveolar crest height and osseous defect depth were measured. All measurements were repeated at 1 year-reentry. Sixteen defects were debrided and grafted (test sites) and 13 defects were debrided only (control sites). Soft tissue measurements showed no statistical differences between the 2 groups. Defect fill was significantly greater with CCBA (1.75 mm) than with DEBR (0.56 mm). Defect depth reduction was 2.06 mm for CCBA and 0.78 mm for DEBR. These values correspond to a percent-defect resolution of 60% for CCBA and 29% for DEBR. Hard tissue measurements showed significant differences between the 2 groups. CCBA seems to be effective in the short-term treatment of intraosseous periodontal defects.

Healing of the intrabony periodontal lesion following root conditioning with citric acid and wound closure including an expanded PTFE membrane

The effect of citric acid conditioning of the root surface in conjunction with gingival flap surgery including barrier membranes (expanded polytetrafluoroethylene) was clinically evaluated in 26 intrabony periodontal defects in 23 patients. Control treatment included gingival flap surgery with barrier membranes alone. Twelve defects were treated with the experimental and 14 with the control protocol. Healing was evaluated 12 months after surgery. Initial probing depths approximated 6.9 mm and defect depths measured during surgery exceeded 4 mm. The patients exhibited good oral hygiene over the study interval as substantiated by low plaque and bleeding scores. Acid conditioning of the root surface did not enhance periodontal healing in this study, similar amounts of defect resolution were observed following either treatment protocol. Probing depth reduction generally approximated 1.8 mm; gain of clinical attachment, 0.8 mm; and defect bone fill, 1.2 mm. Under the prevailing conditions, the barrier membrane procedure apparently gave a healing result beyond which further improvement could not be achieved by root surface conditioning.

Autogenous and allogeneic bone grafts in periodontal therapy

This article is limited to a review of bone autografts and allografts, as used in periodontal therapy. The various graft materials are discussed with respect to case reports, controlled clinical trials, and human histology. Other reviewed areas are wound healing with periodontal bone grafts, tissue banking and freeze-dried bone allografts, and the use of bone grafts in guided tissue regeneration.

A Veterans Administration Cooperative Study of biphasic calcium phosphate ceramic in periodontal osseous defects

One hundred thirty-seven V.A. patients were randomized to one of three treatment groups to evaluate the efficacy of biphasic calcium phosphate (BCP) ceramic in the treatment of periodontal osseous defects. This material was tested against both autogenous bone implant and open flap curettage procedures. Baseline probing attachment level, Navy plaque index, and gingival index were recorded for all patients. These parameters were monitored for 3 years. At the end of this period, 101 patients had completed the study. Although the plaque and gingival indices steadily increased with time, there were no statistically significant differences among the treatment groups. Patients in the ceramic group had a gain in attachment level of 1.0 mm; those in the curettage group, 0.9 mm; and 0.4 mm for those in the bone implant group. Although the BCP patients had a greater gain, the difference was not statistically significant. In this veteran population, not only did BCP patients fail to outperform those in the control groups, all three treatment groups were similarly ineffective.

Regenerating bone in clinical periodontics

Bone autografts and allografts, various alloplastic materials, and guided tissue regeneration are used to reconstruct lost periodontal tissues. This paper focuses on controversies related to these therapeutic modalities as well as their role in periodontal regeneration.

HTR polymer grafts in human periodontal osseous defects. I. 6-month clinical results

HTR polymer was evaluated as a grafting material in periodontal osseous defects in 21 adult patients. Following initial preparation and pre-surgical documentation with standardized measurements, radiographs, and photographs, vertical osseous defects were treated with surgical open flap debridement alone (DEBR) or with DEBR plus placement of HTR polymer graft material. Patients were followed with frequent recalls until surgical re-entry at about 6 months for documentation and any needed remedial therapy. Re-entry data show that use of HTR polymer grafts resulted in significantly better mean defect fill of 2.2 mm (60.8%) compared to 1.0 mm (32.2%) with DEBR alone (P less than .001). Other hard tissue findings such as residual defect depth, crestal resorption, and percent defect resolution showed similar clinically superior results with the use of HTR polymer. Soft tissue findings showed significant differences in favor of HTR for decrease in probing depth and gain in clinical attachment. These results are similar to those reported with other graft materials. Over a 6-month period, HTR polymer was found to show promise for the repair of periodontal osseous defects.

The use of collagen membrane barriers in conjunction with combined demineralized bone-collagen gel implants in human infrabony defects

The present study evaluated the clinical efficacy of a combined graft of autolysed antigen-extracted allogeneic (AAA) bone and microfibrillar collagen (Zyderm) covered with a resorbable collagen membrane in human infrabony defects. The results were compared at 1 year with debrided controls, AAA bone grafts alone, combined AAA bone-collagen grafts (without membrane), and debrided defects covered only with collagen membranes. Ten adult patients having moderate periodontitis and one or more radiographically detectable angular defects probing 6 mm to 7 mm in each quadrant were included. Preoperative measurements of clinical attachment, probing depth, and recession were taken and compared at 1 year following surgery. Measurements at the time of surgery and at 1 year re-entry evaluated osseous defect fill and crestal changes. Each patient received the 5 treatment modalities. Treatment results per patient were used for a series of 2-way analyses of variance. When a significant difference was found, a Student-Newman-Keuls multiple range test was used to determine which treatments were statistically different (0.05 probability level) from each other. All treatment modalities showed improvement over the debrided controls. Similar advantages to using bone-collagen grafts with and without membranes were found in reducing probing depths and gaining new attachment. Significant differences were found when comparing the multifaceted bone graft collagen-membrane technique to all others in achieving superior defect fill. Ninety three percent of all defects treated resulted in 50% or greater fill.

A comparison of freeze-dried bone allograft and demineralized freeze-dried bone allograft in human periodontal osseous defects

This study was conducted to clinically compare freeze-dried bone allograft (FDBA) and demineralized freeze-dried bone allograft (DFDBA). Twenty-two defects (11 intrapatient pairs) in 9 patients were grafted with either DFDBA or FDBA. Evaluations were based on standardized radiographs, presurgical and postsurgical soft tissue measurements using the cemento-enamel junction as a fixed reference point, and osseous measurements at the time of surgery. Grafted sites were re-entered at a minimum of 6 months following placement. A mean osseous repair of 1.7 mm (59%) occurred with DFDBA and 2.4 mm (66%) with FDBA. A mean clinical attachment gain of 1.7 mm was obtained with DFDBA and 2.0 mm with FDBA. Probing depths decreased a mean of 2.00 mm with both DFDBA and FDBA. These findings reveal no significant differences between the two materials in primarily intraosseous defects when evaluated at a minimum 6 months postsurgery.

Osseous defect responses to hydroxylapatite grafting versus open flap debridement

Data from a large number of defects (152) treated with hydroxylapatite (HA) grafts were compared to those from a large number of defects (111) treated by surgical debridement alone (DEBR). Comparison of initial and re-entry surgery measurements showed that both the analysis of relative defect fill and the intrapatient comparisons demonstrated an advantage to the use of HA graft material. 58% of the HA-grafted defects were judged to have a positive (greater than or equal to 50% defect fill) hard tissue response compared to 30% for DEBR. Minimal responses (failures) were 4 times as numerous with DEBR. Similarly, within each patient, HA grafting proved of benefit, particularly regarding hard tissue changes. The use of HA graft materials appears to be of clinical benefit in a majority of defects and a majority of patients.

Comparison of freeze-dried bone allograft and porous hydroxylapatite in human periodontal defects

This study was conducted to clinically compare the efficacy of freeze-dried bone allograft (FDBA) and porous hydroxylapatite granules. Nineteen pairs of intraosseous defects were grafted in seven patients. One defect of each pair was implanted with FDBA, the other with granular porous hydroxylapatite. Matching defects were treated similarly in all other aspects. Evaluations were based on both preoperative and postoperative measurements from a fixed reference point, standardized radiographs, surgical osseous measurements, and histology of degranulated tissues. Grafted sites were reentered 6 to 11 months postsurgery. Results showed a mean osseous fill of 2.1 mm for FDBA versus 1.3 mm for granular porous hydroxylapatite (P = .07). A mean clinical attachment gain of 2.2 mm for FDBA versus 1.3 mm for granular porous hydroxylapatite (P less than .05), and a mean decrease in probing depths of 3.0 mm for FDBA versus 1.4 mm for granular porous hydroxylapatite (P less than 0.5) was found. FDBA was clinically indistinguishable from host bone, whereas porous hydroxylapatite appeared to be separated from host bone by soft tissue. The data and clinical findings suggested that FDBA may have some enhanced reparative potential when compared to granular porous hydroxylapatite in the treatment of periodontal defects in humans.

Healing after treatment of periodontal intraosseous defects. V. Effect of root planing versus flap surgery

The present study compared surgical therapy to root planing alone in the treatment of periodontal intraosseous defects. 25 defects in 14 patients were subjected to root planing only and another 25 defects in the same patients were surgically exposed and citric acid treated. The healing response was evaluated 6 months after treatment. The mean gain of probing attachment level was 0.8 mm in the root-planed defects as compared to 1.3 mm for the surgically exposed and acid-treated defects. The probing bone level improved an average of 0.2 mm for the root-planed areas as compared to 0.6 mm for the acid-treated defects. The mean preoperative probing pocket depths of 6.7 mm and 6.8 mm for the 2 groups were reduced to 5.2 mm and 4.1 mm, respectively. The differences in these parameters were statistically significant between the 2 groups. However, both groups demonstrated limited regeneration.

Evaluation of durapatite ceramic as an alloplastic implant in periodontal osseous defects. II. Twelve month reentry results

Thirteen patients received Durapatite, a hydroxylapatite ceramic (Periograf), as a bone implant material in various types of intrabony defects following internally beveled full thickness flaps, root planing, and defect debridement. All osseous margins and defects were measured from the cemento-enamel junction (CEJ) at specific locations using a standardized periodontal probe. Similarly debrided, nonimplanted defects served as controls. Defect selection as either experimental or control site was based on an alternating defects design after local therapy was completed. Periodontal dressing and systemic tetracycline were used for 10 days. Postsurgical visits for documentation and plaque control were at 10, 20 and 30 days, and 3, 6, 9 and 12 months. Measurements relating to defect changes were made at the 12-month surgical reentry. For evaluation purposes original defect depths were divided into three groups. In Group I (less than 3 mm) defect fill was 1.0 mm (47%) for the implanted defects and 0.3 mm (33%) for the control sites (significantly different at P less than 0.05). In Group II (3-6 mm) defect fill of 1.7 mm (44%) for implanted sites was significantly better (P less than 0.05) than the 0.8 mm (29%) found in control sites. In the deepest group (Group III, greater than 6 mm) Durapatite placement yielded 2.1 mm (32%) of defect fill while debridement alone resulted in 1.8 mm (26%) of fill (P greater than 0.05). Hard tissue responses demonstrated a substantial advantage for use of Durapatite over controls, while soft tissue changes were similar for both.(ABSTRACT TRUNCATED AT 250 WORDS)

Healing after treatment of periodontal intraosseous defects. IV. Effect of a non-resective versus a partially resective approach

2 regenerative surgical approaches using citric acid conditioning, were compared in the treatment of deep intraosseous periodontal defects. The first approach was non-resective in that no osseous tissue was removed. The second, a partially resective approach, involved reduction of the osseous defect depth by removal of some supporting bone. 16 patients and a total of 26 defects, with probing pocket depth greater than or equal to 7 mm, were included in the study. The depths of the corresponding osseous defect, as revealed during surgery were greater than or equal to 5 mm. The results demonstrated mean gains in probing attachment level of 0.7 mm for the partially resected group and 1.1 mm for the non-resected group. Corresponding gains in probing bone levels were recorded in the defect sites for each group. Probing pocket depth was reduced from 7.5 mm to 4.0 mm in the partially resected group and from 7.9 mm to 5.3 mm in the non-resected group. Both procedures caused loss of attachment and bony support from adjacent tooth surfaces involved by the surgical procedure. Slightly more loss of attachment and bone was experienced by the partially resected group (range 1.2-1.5 mm) than by the non-resective group (range 0.1-0.9 mm).

Healing after treatment of periodontal intraosseous defects. III. Effect of osseous grafting and citric acid conditioning

The present study was performed to determine whether the healing of periodontal intraosseous defects could be improved through the combined use of citric acid conditioning of the root surfaces and grafting of autogenous intraoral cancellous bone. 28 proximal defects in 19 patients were treated surgically including acid conditioning of the root surfaces. Another 25 defects in these patients were treated with acid conditioning combined with osseous grafts using the maxillary tuberosity areas as donor sites. Both therapies, e.g., citric acid conditioning alone and acid conditioning combined with osseous grafting resulted in approximately 1 mm gains of probing attachment and probing bone levels. Within the parameters of this study, osseous grafting did not enhance the effect of citric acid conditioning alone. Limited improvement of the treated defects of the present study was obtained in spite of the use of supplementary regenerative techniques.