Pamela K. McClain

Platelet-Derived Growth Factor Promotes Periodontal Regeneration in Localized Osseous Defects: 36-Month Extension Results From a Randomized, Controlled, Double-Masked Clinical Trial

BACKGROUND Recombinant human platelet-derived growth factor (rhPDGF) is safe and effective for the treatment of periodontal defects in short-term studies up to 6 months in duration. We now provide results from a 36-month extension study of a multicenter, randomized, controlled clinical trial evaluating the effect and long-term stability of PDGF-BB treatment in patients with localized severe periodontal osseous defects. METHODS A total of 135 participants were enrolled from six clinical centers for an extension trial. Eighty-three individuals completed the study at 36 months and were included in the analysis. The study investigated the local application of β-tricalcium phosphate scaffold matrix with or without two different dose levels of PDGF (0.3 or 1.0 mg/mL PDGF-BB) in patients possessing one localized periodontal osseous defect. Composite analysis for clinical and radiographic evidence of treatment success was defined as percentage of cases with clinical attachment level (CAL) ≥2.7 mm and linear bone growth (LBG) ≥1.1 mm. RESULTS The participants exceeding this composite outcome benchmark in the 0.3 mg/mL rhPDGF-BB group went from 62.2% at 12 months, 75.9% at 24 months, to 87.0% at 36 months compared with 39.5%, 48.3%, and 53.8%, respectively, in the scaffold control group at these same time points (P <0.05). Although there were no significant increases in CAL and LBG at 36 months among all groups, there were continued increases in CAL gain, LBG, and percentage bone fill over time, suggesting overall stability of the regenerative response. CONCLUSION PDGF-BB in a synthetic scaffold matrix promotes long-term stable clinical and radiographic improvements as measured by composite outcomes for CAL gain and LBG for patients possessing localized periodontal defects ( ClinicalTrials.gov no. CT01530126).

Local minocycline as an adjunct to surgical therapy in moderate to severe, chronic periodontitis

OBJECTIVE The aim of the study was to evaluate the effects of minocycline microspheres on periodontal probing depth reduction when used in combination with surgery in adults with moderate to severe, chronic periodontitis. MATERIAL AND METHODS Sixty patients with a minimum of one non-molar periodontal site > or =6 mm in two oral quadrants received either local minocycline microspheres at baseline, immediately following each of two surgical therapies (Weeks 2 and 3), and at Week 5 or surgery alone. RESULTS The mean probing depth reduction at Week 25 at sites > or =5 mm at baseline was 2.51 mm in the test group and 2.18 mm in the control group. Smokers in the test group had a significantly greater probing depth reduction (2.30 mm) than smokers in the control group (2.05 mm). The number of sites with probing depth reductions of > or =2 and > or =3 mm were significantly higher in the test group than in the control group. CONCLUSION Applications of local minocycline as an adjunct to surgery in adults with moderate to severe, chronic periodontitis were associated with statistically significant greater reductions in probing depth than surgery alone.

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.

AAP President’s Address*

Esteemed colleagues, distinguished guests, cherished family, and friends: welcome to Los Angeles – the City of Angels. WinstonChurchill once stated, ‘‘Continuous effort – not strength or intelligence – is the key to unlocking our potential.’’ This meeting reflects the continuous efforts of our fellow members, including the Continuing Education Oversight Committee chaired by Dr. Robert Faiella (who is currently the president elect of the American Dental Association), staff, and an outstanding faculty who will be presenting for the next 3 days. Unlocking our potential relies on what weknowandhavedone in the past, howweapproach the future, and what we are doing today to enhance periodontics for ourselves as practitioners, but ultimately for the patients we all serve. We can look at the past 26 years with great fondness as we dedicate this meeting to our Executive Director, Alice DeForest. Alice will be retiring after this year’s meeting, and we are forever grateful for her contributions to our profession and this Academy. Alice has helped shape the AAP into a world-class organization, and in a few moments, we’ll have the opportunity to hear more about those accomplishments. As your president this year, I have focused on continuing to advance the great foundation of science on which our Academy and profession have been built. As periodontists, we constantly seek to refine the sophisticated techniques we use, such as regenerative therapy, periodontal plastic surgery, tissue engineering, and implant therapy. We also strive to enhance our understanding of the basic sciences and how to apply it clinically. We’re dedicated to providing the most appropriate care to our patients while pushing the boundaries of the research available to us. This means anticipating complications associated with our therapies, such as peri-implantitis and peri-mucositis. Our Academy has responded to these challenges by establishing definitions and explaining what to look for when an implant case goes awry. More and more implants are placed each year, and it is critical that we establish proper criteria for assessing and managing problematic implants – especially since we are oftentimes the ‘‘go to’’ professionals in treating these complications. I am certain that implants will remain an important treatment option for our patients, but has the pendulum swung too far in favor of removing teeth we once considered salvageable? The importance of preserving the natural dentition and using strategies such as periodontal regeneration to help us achieve that goal is a critical aspect of our specialty. Over the past several years, the amount and quality of research on growth factors and tissue engineering have markedly increased. With more and more therapeutic options, our ability to provide predictable outcomes for many periodontal defects is improving. Looking toward the future, the Academy is in the planning stages of a Workshop on Periodontal Regeneration and Tissue Engineering, which will contribute to advances in these areas. Advocating for the specialty of periodontics is another of our key concerns as evidenced by responses to this year’s membership survey. For the past 2 years, an AAP task force has been investigating ways to enhance our relationships with the general dentist. As a result of these efforts, we have doubled the number of periodontal article placements in dental trade publications. We are pleased to see a positive shift in the sentiment of key opinion leaders and dental trade editors toward periodontists and have developed numerous resources to support your efforts in your own practices. Ultimately it’s the oneon-one relationship between the periodontist and their referring dentists that builds mutual trust and commitment. The Academy cannot put patients in your chairs, but we can provide resources to help enhance relationships with those practitioners who will refer. I encourage each of you to utilize the valuable tools available on perio.org. If you aren’t familiar with them, stop by Member Central at this meeting, and staff will walk you through these resources. In addition to amembership survey this past year, the AAP also conducted a consumer awareness survey. The results informed us that the majority of the public has heard of gum disease, but not the term ‘‘periodontal disease.’’ We hope to see that perception change in the advent of recently released findings from the 2009-2010 National Health and Nutrition Examination Survey (NHANES). The AAP has worked closely with the Centers for Disease Control and Prevention (CDC) since 2003 to establish a more accurate assessment of periodontal