Ivan Darby

Progression of chronic periodontitis can be predicted by the levels of Porphyromonas gingivalis and Treponema denticola in subgingival plaque.

INTRODUCTION Chronic periodontitis is an inflammatory disease of the supporting tissues of the teeth associated with bacteria. Diagnosis is achieved retrospectively by clinical observation of attachment loss. Predicting disease progression would allow for targeted preventive therapy. The aim of this study was to monitor disease progression in patients on a maintenance program and determine the levels of specific bacteria in subgingival plaque samples and then examine the ability of the clinical parameters of disease and levels of specific bacteria in the plaque samples to predict disease progression. METHODS During a 12-month longitudinal study of 41 subjects, 25 sites in 21 subjects experienced disease progression indicated by at least 2 mm of clinical attachment loss. Real-time polymerase chain reaction was used to determine the levels of Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Fusobacterium nucleatum, and Prevotella intermedia in subgingival plaque samples. RESULTS No clinical parameters were able to predict periodontal disease progression. In sites undergoing imminent periodontal disease progression within the next 3 months, significant partial correlations were found between P. gingivalis and T. forsythia (r = 0.55, P < 0.001) and T. denticola and T. forsythia (r = 0.43, P = 0.04). The odds of a site undergoing imminent periodontal disease progression increased with increasing levels of P. gingivalis and T. denticola. CONCLUSION Monitoring the proportions of P. gingivalis and T. denticola in subgingival plaque has the potential to help identify sites at significant risk for progression of periodontitis, which would assist in the targeted treatment of disease.

Oral health risk factors for bisphosphonate-associated jaw osteonecrosis.

PURPOSE To investigate the role of oral health, including periodontitis, as a risk factor for bisphosphonate-associated jaw osteonecrosis (ONJ). MATERIALS AND METHODS This cross-sectional study compared cases with an ONJ history to controls. All had a history of bisphosphonate treatment for malignancy. Participants underwent oral examination, gingival crevicular fluid (GCF) sampling, and phlebotomy. Serum was analyzed for biochemical parameters, bone markers, and immunoglobulin G titers against 4 periodontitis-associated bacteria. Cytokine levels were determined in GCF using a multiplex assay. RESULTS Caries development was comparable between groups. Periodontitis was significantly associated with ONJ using the US National Center for Health Statistics periodontitis definition (P = .002), at least 1 site with a probing depth of at least 4 mm (P = .003), and the percentage of sites per participant with a probing depth of 4 to 5 mm (P = .044). Immunoglobulin G titer against Porphyromonas gingivalis and GCF interleukin-1β level were also significantly associated with ONJ (P = .018 and P = .044, respectively). CONCLUSION In participants with a history of bisphosphonate treatment for malignancy, periodontitis was associated with ONJ when measured using clinical parameters, serum immunoglobulin G titers against P gingivalis, and GCF interleukin-1β levels, suggesting that periodontitis and associated bacteria are potentially important in ONJ pathophysiology.

Ridge preservation: what is it and when should it be considered

The resorption of bone following extraction may present a significant problem in implant and restorative dentistry. Ridge preservation is a technique whereby the amount of bone loss is limited. This paper discusses the scientific literature examining the healing post-extraction and ridge preserving techniques, primarily from the perspective of implant dentistry. Some indications for ridge preservation and methods considered appropriate are discussed.

A review of the clinical implications of bisphosphonates in dentistry

Bisphosphonates are drugs that suppress bone turnover and are commonly prescribed to prevent skeletal related events in malignancy and for benign bone diseases such as osteoporosis. Bisphosphonate associated jaw osteonecrosis (ONJ) is a potentially debilitating, yet poorly understood condition. A literature review was undertaken to review the dental clinical implications of bisphosphonates. The present paper briefly describes the postulated pathophysiology of ONJ and conditions with similar clinical presentations. The implications of bisphosphonates for implantology, periodontology, orthodontics and endodontics are reviewed. Whilst bisphosphonates have potential positive applications in some clinical settings, periodontology particularly, further clinical research is limited by the risk of ONJ. Prevention and management are reviewed, including guidelines for reducing cumulative intravenous bisphosphonate dose, cessation of bisphosphonates prior to invasive dental treatment or after ONJ development, and the use of serum beta-CTX-1 in assessing risk. In the context of substantial uncertainty, the implications of bisphosphonate use in the dental clinical setting are still being determined.

Mass Spectrometric Analyses of Peptides and Proteins in Human Gingival Crevicular Fluid

Gingival crevicular fluid (GCF) is a pathophysiological fluid that flows into the oral cavity. Human GCF was collected using sterile glass microcapillary tubes from inflamed periodontal sites in patients who had a history of periodontal disease and were in the maintenance phase of treatment. Samples from individual sites were analyzed using MS techniques both before and following HPLC. GCF samples were also pooled and subjected to SDS-PAGE, in-gel digestion and MS analyses using both MALDI-TOF/TOF MS and nanoLC-ESI-MS/MS. MS spectra were used to search human protein sequence databases for protein identification. With these approaches, 33 peptides and 66 proteins were positively identified in human GCF. All of the peptides discovered in this study are reported in GCF here for the first time. Forty-three of the identified proteins, such as actin and the actin binding proteins profilin, cofilin and gelsolin, have not been reported in GCF before.

A Systematic Review of the Use of Growth Factors in Human Periodontal Regeneration

BACKGROUND There is a large body of evidence using cells and animal models demonstrating the effectiveness of growth factors in periodontal regeneration. However, there appears to be minimal literature comparing the efficacy of growth factors in human periodontal regeneration compared to other techniques and procedures. Therefore, the aim of this study is to perform a systematic review of human studies using growth factors for periodontal regeneration and to compare the efficacy of these growth factors to other accepted techniques for periodontal regeneration. METHODS An electronic and manual search based on agreed search phrases between the primary investigator and a secondary investigator was performed to identify the use of growth factors in periodontics for the literature review. The articles that were identified by this systematic review were analyzed in detail, which included the study of their inclusion and exclusion criteria, outcome measures determination and analysis, risk of bias, adverse events, and conclusions or inference of the efficacy of growth factors to the general population. RESULTS Five papers fulfilled the inclusion criteria. Two papers were identified that had sufficiently similar study design that a meta-analysis of their outcomes was possible. Most of the reported outcomes from the selected papers were descriptive. The articles demonstrated periodontal regeneration at least comparable to their respective positive controls, with only a couple of articles demonstrating significantly greater outcomes compared to their respective positive controls. Histologic evidence demonstrated greater periodontal regeneration when using growth factors compared to other regenerative techniques and an increased healing and bone maturation rate compared to other regenerative and bone augmentation techniques in these human studies. CONCLUSIONS Within the limits of this systematic review, the use of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) led to greater clinical attachment level gain of ≈1 mm compared to an osteoconductive control, β-tricalcium phosphate (β-TCP). The use of rhPDGF-BB led to greater percentage bone fill of ≈40% compared to the osseoconductive control, β-TCP. Last, the use of rhPDGF-BB led to an increased rate of bone growth of ≈2 mm compared to the osseoconductive control, β-TCP.

Oral hygiene and periodontal disease in Victorian nursing homes

OBJECTIVE To investigate oral hygiene and periodontal disease in residents of Victoria nursing homes. BACKGROUND   The Australian population is ageing with a growing proportion of elderly Australians living in nursing homes. With declining edentulism rates, periodontal disease is becoming more prevalent in this population. MATERIALS AND METHODS A total of 275 dentate residents from 31 Victorian nursing homes had a questionnaire and clinical examination using the Visual Plaque Index and a modified Community Periodontal Index. RESULTS Self-reported oral hygiene habits of residents were poor, with less than one-third of residents cleaning their teeth twice daily or more. Periodontal health was found to be extremely poor, and the prevalence of 4 mm+ periodontal pockets was 35.6%, with 10.2% having 6 mm+ pockets. Logistic regression found that age, gender, number of teeth present and oral hygiene were all strongly associated with the prevalence of 4 mm+ periodontal pockets. CONCLUSION Poor oral hygiene and the presence of significant plaque and calculus were common findings in this study. Periodontal diseases are a significant problem for residents in nursing homes. Addressing this health issue will require improved training for carers and better access to appropriate dental services.

Maxillary sinus floor elevation and grafting with deproteinized bovine bone mineral: a clinical and histomorphometric study

OBJECTIVES This study evaluated the histomorphometric and clinical outcomes of maxillary sinus floor elevation using deproteinized bovine bone mineral (DBBM). MATERIAL AND METHODS Maxillary sinuses with a residual vertical height of <5 mm were augmented with DBBM alone before implant placement 9 months later. At the time of implant surgery, trephine samples were removed and histological and histomorphometric analyses were performed to examine the percentage of bone and residual graft using point counting and software-aided analysis. Patients were recalled for clinical and radiographic examination up to 3 years later. RESULTS Twenty-five patient specimens were analysed. The percentages of regenerated bone and residual graft material were 19% and 40%, respectively. Software-aided analysis was comparable to point counting. Twelve patients attended for clinical follow-up. Implants placed into this regenerated bone exhibited success and survival rates of 100% after an average follow-up of 3 years. The average vertical height gained was 7.9 mm. CONCLUSIONS The use of DBBM alone in maxillary sinus floor elevation is a predictable method to gain vertical bone height in the posterior maxilla.

Non‐surgical management of periodontal disease

Non-surgical removal of plaque and calculus has been part of the initial phase of the management of patients with gingivitis and periodontitis for decades. It consists of patient motivation and oral hygiene instruction as well as mechanical removal of supra and subgingival plaque deposits. The purpose of this review was to assess recent changes. The article reports on changes in our understanding of plaque as a biofilm, developments in patient plaque control, chemical plaque control and scaling instruments. It also comments on full-mouth disinfection, the use of lasers and host modulation. Modern technology has made removal of microbial deposits by the patient and dental professionals more efficient. However, other advancements need to be used in conjunction with mechanical debridement at this time.

Gingival crevicular fluid proteomes in health, gingivitis and chronic periodontitis

OBJECTIVE The aim of this study was to compare the proteome composition of gingival crevicular fluid obtained from healthy periodontium, gingivitis and chronic periodontitis affected sites. BACKGROUND Owing to its site-specific nature, gingival crevicular fluid is ideal for studying biological processes that occur during periodontal health and disease progression. However, few studies have been conducted into the gingival crevicular fluid proteome due to the small volumes obtained. METHODS Fifteen males were chosen for each of three different groups, healthy periodontium, gingivitis and chronic periodontitis. They were categorized based on clinical measurements including probing depth, bleeding on probing, plaque index, radiographic bone level, modified gingival index and smoking status. Gingival crevicular fluid was collected from each patient, pooled into healthy, gingivitis and chronic periodontitis groups and their proteome analyzed by gel electrophoresis and liquid chromatography electrospray ionization ion trap tandem mass spectrometry. RESULTS One hundred and twenty-one proteins in total were identified, and two-thirds of these were identified in all three conditions. Forty-two proteins were considered to have changed in abundance. Of note, cystatin B and cystatin S decreased in abundance from health to gingivitis and further in chronic periodontitis. Complement proteins demonstrated an increase from health to gingivitis followed by a decrease in chronic periodontitis. Immunoglobulins, keratin proteins, fibronectin, lactotransferrin precursor, 14-3-3 protein zeta/delta, neutrophil defensin 3 and alpha-actinin exhibited fluctuations in levels. CONCLUSION The gingival crevicular fluid proteome in each clinical condition was different and its analysis may assist us in understanding periodontal pathogenesis.