International Journal of Periodontics & Restorative Dentistry, 02/1995

Clinical experience, technical ability, and intution are indispensable byt are no longer sufficient as the sole clincal skills necessary toprovide the best outcomes from periodontal and peri-implant regeneration treatment. This article describes a comprehensive and rigorous methodologic framework to assess the available evidence contained within the literature. This assesment tool is referred to as the evidence-based method. The methodology was used by a series of task forces convened to evaluate three common areas of clinical regenerative treatment. The major goals of these task forces were: (1) to increase the strength of the inference that practitioner can derive from the base of knowledge contained within the literature, (2) to develop algorithms to improve the predictability of regeneration treatment, and (3) to determine methods that can be used to predictably transfer the value of therapy to the patient.

A task force of periodontists established clincal and histologic outcomes (goals) for the treatment of intrabony defects and researched the literature for techniques that would most predictability achieve these goals. The group also identified factors that could influence predictability. The treatment outcomes selected by the task force included regeneraton of a true attachment apparatus; gain in bone and probing attachment levels; reduction in probing pocket depth; minimal gingival recession; increased patient comfort; esthetic appearance and state of wellness; and maintenance of health; comfort; and function over time. Based on evidence it was concluded that guided tissue regeneration, guided tissue regeneration combined with the use of decalcified freeze dried bone allografts, and freeze-dried allografts alone are the most predictable regenerative procedures for achieving selected treatment outcomes. Various factors, such as patient characteristics, the morphology of the defect, and the surgical technique can influence the healing response of intrabony defects. Patient factors, such as plaque control, compliance, and cigarette smoking, can directly affect predictability of periodontal regeneration. Defect selection is critical, and deep and narrow defects are the most predictable response to regenerative procedures. The number of remaining bony walls is important in grafting procedures, but their influence is questionable in guided tissue regeneration. Various technical procedures, such as flap design, defect debridement, and wound protection , may influence the predictability of regeneration.

The purpose of the present evidence-based critical review was to define goals and outcomes for regenerative therapy Class II furcation defects and rank the efficacy of current regenerative procedures based on the available literature. Meta-analysis was employed to quantitate the mean oveall expected changes and compare various techniques. The evidence presented in the literature was used to determine factors affecting regeneration of Class II furcation defects. These factors were used to establish decision-making trees to enhance success and highlight potential shortcomings of the technique. Guided tissue regeneration, used alone or in combination with bone replacement grafts, had the highest overall ranking. Mean reduction in probing depths and gains in vertical and horizontal attachment levels were all statistically significant at 6 months. Similar results were obtained in the 12-month studies. Compared to flap debridemant, guided tissue regeneration resulted in greater reduction in probing depths and greater gains in vertical and horizontal attachment levels. Guided tissue regeneration provided almost identical results whether used with or without root conditioning, suggesting that root conditioning does not offer an adjunctive effect. A combination of guided tissue regeneration and bone replacement grafts yielded better results than did guided tissue regeneration alone in reducing probing depths and increasing vertical attachment levels. The decision-making trees derived from analysis of these results may assist the clinician in improving success and predictability of guided tissue regeneration procedures in Class II furcation defects.

Guided bone regeneration is a new technique that evolved following the guided tissue regeneration procedure for regeneration of lost periodontium. The objective of guided bone regeneration is to promote bone formation in osseous deformitites either before or in conjunction with endosseous implant placement. Osseous defects consist mainly of extraction sited, dehiscences or fenestrations, and localized ridge deformitites. In addition, bone defects may either provide natural spacemaking or be nonspacemaking. A plethora of publications indicate that the guided bone regeneration technique can be used successfully in all types of defects. Nonspacemaking defects usually require bone graft materials to assist in space maintenance and enhance bone formation. Fixation pins are also used, either with or without graft material, in this regard. The scientific literature on guided bone regeneration was review by a task force to determine techniques proven to increase predictability relative to successful patient outcomes and to develop specific evidence based diagnostic and treatment decision trees.

This is a summary report from An Evidence-Based Treatment Approach: Successful Regenerative Outcomes, Task Force 4, Translating Clinical Outcomes to Patient Value. It represents recommendations for translating the clinical benefits of regenerative therapies to value that the patient can understand and accept. A review of the evidence on translating clinical outcomes to the patient value was presented to the task force for discussion. Then outcome criteria established by other task forces on clinical applications of regenerative therapy were used to evaluate the evidence. Published literature related to many different areas, such as clinician-patient communication, patient behavior, the role of other dental professionals, and organization of the practice and its processes, was included in this review. Outcomes charts and decision-making trees were developed to provide a framework for the recommendations of the task force. The ultimate objectives of this task force were to hepl the practitioner to clearly perceive the benefits that regeneration can provide to patients and to help the clinician to present the facts in a manner that will increase patients' acceptance of the recommended treatment.

Biphasic calcium phosphate, consisting of B-tricalcium phosphate and hydroxyapatite, was implanted in wide and deep periodontal osseous defects of monkeys in combinatoin with the guided tissue regeneration technique. After 12 weeks, sites treated with a combination of biphasic calcium phosphate and guided tissue regeneration maintained the shape of the ridgem but both guided tissue regeneration and control sites (untreated) showed extreme resorption. A histopathologic investigation revealed that numerous machrophages contained small particles of ceramic within their vesicles and that active bone replacement occurred from the surrounding bone. Biphasic calcium phosphate has osteoconductive potential and this potential may be related to degradation by macrophage phagocytosis.