Michael P. Mills

Periodontal Regeneration – Intrabony Defects: A Consensus Report From the AAP Regeneration Workshop

BACKGROUND Treatment of intrabony defects is an important therapeutic goal of periodontal therapy. The goal of this consensus report was to critically appraise the evidence for the available approaches for promoting periodontal regeneration in intrabony defects. In addition to evaluating the effectiveness of new regenerative approaches for intrabony defects, recommendations for future research were defined for this area. METHODS A systematic review was conducted using computerized searches of PubMed and Cochrane databases, supplemented with screening of references in original reports, review articles, and a hand search in selected journals. All searches were focused on regenerative approaches with histologic evidence of periodontal regeneration (proof of principle), clinical trials, and case reports. For purposes of analysis, change in intrabony defect fill was considered the primary outcome variable, with change in clinical attachment as a secondary outcome. The SORT (Strength of Recommendation Taxonomy) grade was used to evaluate the quality and strength of the evidence. During the consensus meeting, the group agreed on the outcomes of the systematic review, pertinent sources of evidence, clinical recommendations, and areas requiring future research. RESULTS The systematic review, which was conducted for the consensus conference, evaluated the effectiveness of the use of biologics for the treatment of intrabony defects. Enamel matrix derivative (EMD) and recombinant human platelet-derived growth factor-BB (rhPDGF-BB) with β-tricalcium phosphate were shown to be efficacious in regenerating intrabony defects. The level of evidence is supported by multiple studies documenting effectiveness. The clinical application of biologics supports improvements in clinical parameters comparable with selected bone replacement grafts and guided tissue regeneration (GTR). Factors negatively affecting regeneration included smoking and excessive tooth mobility. CONCLUSIONS Periodontal regeneration in intrabony defects is possible on previously diseased root surfaces, as evidenced by a gain in clinical attachment, decreased pocket probing depth, gain in radiographic bone height, and overall improvement in periodontal health. These clinical findings are consistent with available histologic evidence. Clinical improvements can be maintained over long periods (>10 years). Although bone replacement grafts have been the most commonly investigated modality, GTR, biologics, and combination therapies have also been shown to be effective. Future research should emphasize patient-reported outcomes, individual response differences, and emerging technologies to enhance treatment results. CLINICAL RECOMMENDATIONS Early management of intrabony defects with regenerative therapies offers the greatest potential for successful periodontal regeneration. The clinical selection and application of a regenerative therapy or combination of therapies for periodontal regeneration should be based on the clinicians experiences and understanding of the regenerative biology and technology. This decision-making process should take into consideration the potential adverse influence of factors, such as smoking, poor oral hygiene, tooth mobility, and defect morphology, on regeneration. Management should be coupled with an effective maintenance program for long-term success.

Quantitative Distribution of Inflammatory Cells in Recurrent Aphthous Stomatitis

Histologic quantitation of leukocytes in biopsies of recurrent aphthous ulcers revealed at least two morphologically-distinct inflammatory infiltrates. Lymphocytes were found consistently in pre-ulcerative lesions and in the expanding margins of the developing ulcer. In contrast, polymorphonuclear leukocytes predominated only in areas of frank ulceration.

A Randomized Clinical Trial Evaluating rh-FGF-2/β-TCP in Periodontal Defects

Biological mediators have been used to enhance periodontal regeneration. The aim of this prospective randomized controlled study was to evaluate the safety and effectiveness of 3 doses of fibroblast growth factor 2 (FGF-2) when combined with a β-tricalcium phosphate (β-TCP) scaffold carrier placed in vertical infrabony periodontal defects in adult patients. In this double-blinded, dose-verification, externally monitored clinical study, 88 patients who required surgical intervention to treat a qualifying infrabony periodontal defect were randomized to 1 of 4 treatment groups—β-TCP alone (control) and 0.1% recombinant human FGF-2 (rh-FGF-2), 0.3% rh-FGF-2, and 0.4% rh-FGF-2 with β-TCP—following scaling and root planing of the tooth prior to a surgical appointment. Flap surgery was performed with EDTA conditioning of the root prior to device implantation. There were no statistically significant differences in patient demographics and baseline characteristics among the 4 treatment groups. When a composite outcome of gain in clinical attachment of 1.5 mm was used with a linear bone growth of 2.5 mm, a dose response pattern detected a plateau in the 0.3% and 0.4% rh-FGF-2/β-TCP groups with significant improvements over control and 0.1% rh-FGF-2/β-TCP groups. The success rate at 6 mo was 71% in the 2 higher-concentration groups, as compared with 45% in the control and lowest treatment groups. Percentage bone fill in the 2 higher-concentration groups was 75% and 71%, compared with 63% and 61% in the control and lowest treatment group. No increases in specific antibody to rh-FGF-2 were detected, and no serious adverse events related to the products were reported. The results from this multicenter trial demonstrated that the treatment of infrabony vertical periodontal defects can be enhanced with the addition of rh-FGF-2/β-TCP (ClinicalTrials.gov NCT01728844).

Periodontal manifestations of systemic diseases and developmental and acquired conditions: Consensus report of workgroup 3 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions

BACKGROUND A variety of systemic diseases and conditions can affect the course of periodontitis or have a negative impact on the periodontal attachment apparatus. Gingival recessions are highly prevalent and often associated with hypersensitivity, the development of caries and non-carious cervical lesions on the exposed root surface and impaired esthetics. Occlusal forces can result in injury of teeth and periodontal attachment apparatus. Several developmental or acquired conditions associated with teeth or prostheses may predispose to diseases of the periodontium. The aim of this working group was to review and update the 1999 classification with regard to these diseases and conditions, and to develop case definitions and diagnostic considerations. METHODS Discussions were informed by four reviews on 1) periodontal manifestions of systemic diseases and conditions; 2) mucogingival conditions around natural teeth; 3) traumatic occlusal forces and occlusal trauma; and 4) dental prostheses and tooth related factors. This consensus report is based on the results of these reviews and on expert opinion of the participants. RESULTS Key findings included the following: 1) there are mainly rare systemic conditions (such as Papillon-Lefevre Syndrome, leucocyte adhesion deficiency, and others) with a major effect on the course of periodontitis and more common conditions (such as diabetes mellitus) with variable effects, as well as conditions affecting the periodontal apparatus independently of dental plaque biofilm-induced inflammation (such as neoplastic diseases); 2) diabetes-associated periodontitis should not be regarded as a distinct diagnosis, but diabetes should be recognized as an important modifying factor and included in a clinical diagnosis of periodontitis as a descriptor; 3) likewise, tobacco smoking - now considered a dependence to nicotine and a chronic relapsing medical disorder with major adverse effects on the periodontal supporting tissues - is an important modifier to be included in a clinical diagnosis of periodontitis as a descriptor; 4) the importance of the gingival phenotype, encompassing gingival thickness and width in the context of mucogingival conditions, is recognized and a novel classification for gingival recessions is introduced; 5) there is no evidence that traumatic occlusal forces lead to periodontal attachment loss, non-carious cervical lesions, or gingival recessions; 6) traumatic occlusal forces lead to adaptive mobility in teeth with normal support, whereas they lead to progressive mobility in teeth with reduced support, usually requiring splinting; 7) the term biologic width is replaced by supracrestal tissue attachment consisting of junctional epithelium and supracrestal connective tissue; 8) infringement of restorative margins within the supracrestal connective tissue attachment is associated with inflammation and/or loss of periodontal supporting tissue. However, it is not evident whether the negative effects on the periodontium are caused by dental plaque biofilm, trauma, toxicity of dental materials or a combination of these factors; 9) tooth anatomical factors are related to dental plaque biofilm-induced gingival inflammation and loss of periodontal supporting tissues. CONCLUSION An updated classification of the periodontal manifestations and conditions affecting the course of periodontitis and the periodontal attachment apparatus, as well as of developmental and acquired conditions, is introduced. Case definitions and diagnostic considerations are also presented.

Lateral alveolar ridge augmentation using tenting screws, acellular dermal matrix, and freeze-dried bone allograft alone or with particulate autogenous bone.

This randomized prospective study evaluated the clinical benefits of using a corticocancellous mixture of freeze-dried bone allograft alone or in combination (1:1) with particulated autogenous bone for horizontal ridge augmentation and subsequent implant placement. Twenty-four patients with atrophic ridges received lateral ridge augmentations with particulate grafts placed around tenting screws and covered with a fixed acellular dermal matrix membrane. Thirty-three standard-diameter implants were successfully placed in 21 patients after a 24-week graft healing period. Three patients experienced early postoperative infections following the grafting procedure (12.5% of sites). At reentry, the allograft alone group showed similar average horizontal ridge width gains (3.33 ± 0.83 mm) to the combination group (3.09 ± 0.63 mm; P = .44). The mean graft resorption between baseline and reentry averaged 13.89%.

Maxillary anterior ridge augmentation with recombinant human bone morphogenetic protein 2

No human studies exist on the use of recombinant human bone morphogenetic protein 2 (rhBMP-2) on an absorbable collagen sponge (ACS) as a sole graft material for lateral ridge augmentation in large ridge defect sites. This series evaluates the treatment outcome of maxillary anterior lateral ridge augmentation with rhBMP-2/ACS. Twenty patients were treated with rhBMP-2/ACS and fixation screws for space maintenance. Cone beam volumetric tomography measurements were used to determine gain in ridge width, and a bone core biopsy was obtained. The mean horizontal ridge gain was 1.2 mm across sites, and every site gained width.

Osseous healing around immediate implants placed using contour augmentation: A prospective case series

The purpose of this study was to prospectively evaluate the dimensional bone changes around implants placed immediately with buccal contour augmentation. Patients with hopeless maxillary anterior teeth were treated with extraction, immediate implant placement, and simultaneous buccal contour augmentation. Hard tissue measurements were recorded at the time of implant placement and after 3 months of healing. All implants (N = 18) successfully osseointegrated with a mean buccal bone thickness of 2.94 ± 0.21 mm (mean ± SE) at the implant platform. This was significantly greater compared to previous data on immediate implants placed without contour augmentation (2.32 ± 0.17 mm). Buccal contour augmentation in conjunction with immediate implant placement significantly increased peri-implant buccal bone thickness after 3 months of healing.