Microbiome profiles of non-responding and responding paired periodontitis sites within the same participants following non-surgical treatment.

Aim: Periodontitis is a site-specific, chronic disease treated by non-surgical debridement of subgingival plaque. We aimed to determine the microbiome of sites that did not respond to this treatment (NR) compared with paired good responding (GR) sites before and after treatment. Materials and methods: In a longitudinal cohort study, clinical parameters of disease and biological samples were taken prior to and 3 months after treatment. Twelve NR sites from six participants were paired with GR sites within the same participant. Subgingival plaque samples were subjected to bacterial community analysis using 16S rRNA gene sequencing. Results: There were no significant differences in clinical parameters and microbial communities at baseline between GR and NR sites. Bacterial communities in deep pockets were dominated by a small number of species, notably Porphyromonas gingivalis and Treponema denticola. In NR sites three months after treatment there was no significant change in bacterial composition whilst there was a collapse in the abundance of pathobionts in GR sites. Conclusion: NR sites were not identifiable prior to treatment by clinical or microbiological parameters. Treatment failed to disrupt pathogenic bacterial community in NR sites. Targeted suppression of particular species should be considered to initiate community collapse and aid disease resolution.

Dentists' preferences in implant maintenance and hygiene instruction.

BACKGROUND: This study investigated the preferences of dentists in Australia in providing professional implant maintenance and implant-specific oral hygiene instructions (OHI). METHODS: General dentists were surveyed online about their preferences in peri-implant diagnostics, maintenance provision, armamentarium used, and implant OHI techniques and frequency. RESULTS: Most of the 303 respondents (96%) provided maintenance services; 87.6% reviewed implants regularly while 10.7% only performed diagnostics after detecting clinical signs/symptoms. Supragingival prosthesis cleaning was performed by 77.9% of respondents, 35.0% performed subgingival debridement, 41.9% treated peri-implant mucositis and 18.2% treated peri-implantitis. About 15% did not treat nor refer peri-implant disease, including significantly more non-implant providers and dentists without implant training. Maintenance armamentarium commonly included floss (76.3%), prophylaxis (73.9%), plastic curettes (43.3%) and stainless-steel ultrasonics (38.0%). Brushing (86.5%), flossing (73.9%) and interdental brush use (68.3%) were most commonly recommended. Implant OHI was repeated routinely by 57.4% of dentists who provided it. Dentists with greater implant training and experience were more likely to perform reviews and complex maintenance procedures. CONCLUSIONS: Peri-implant diagnostics performed, treatments provided and armamentarium varied among dentists. Implant providers and those with higher levels of training had more preventative approaches to implant OHI. Possible shortcomings in disease management and OHI reinforcement were identified.

Implant education patterns and clinical practice of general dentists in Australia.

BACKGROUND: This study aimed to understand trends in dentists' implant training attendance and correlation to treatment provision. Implant-specific oral hygiene instruction coverage in training programs was investigated. METHODS: A cross-sectional web-survey of dentists registered in Australia was conducted. Respondents were asked about their background, implant training history and treatment provision. Results were analysed by implant provision characteristics and graduation decade. RESULTS: Three hundred and three responses from general dental practitioners (GDPs) were received and analysed. The highest implant training levels attained post-graduation were postgraduate non-specialist qualification (7.9% of respondents), continuing professional development (CPD) (73.6%) versus none (18.5%), with differences between implant providers and non-providers (P < 0.001), different graduation decades (P < 0.001) and those restoring implants or performing surgery as well (P < 0.001). University-based CPD was attended less than dental association/society or implant company CPD. Non-providers were significantly less likely to recall implant oral hygiene instruction sources (P < 0.001). Most GDPs (74.9%) provided implant services, with younger GDPs beginning earlier after graduation. About 16% of respondents did not provide implants once established career-wise. CONCLUSIONS: Dentists might be providing implant treatments increasingly earlier in their careers. Respondents with more training were significantly more likely to perform more complex procedures, while implant training attendance trends varied by graduation decade.

Rapid Chair-Side Test for Detection of Porphyromonas gingivalis.

Porphyromonas gingivalis is a keystone pathogen of chronic periodontitis, and its intraoral levels have been shown to predict disease progression (activity). An accurate and sensitive chair-side (point of care) test to determine disease activity is critical for early intervention and clinical management of disease. This study aimed to develop a rapid, chair-side, saliva-based detection of P. gingivalis. Monoclonal antibodies (mAbs) to the A1-adhesin domain of the P. gingivalis RgpA-Kgp proteinase-adhesin complex were screened by enzyme-linked immunosorbent assay and microbial flow cytometry, with 2 mAbs shown to recognize all laboratory and clinical strains tested, without significantly cross-reacting with other oral bacteria tested. With these mAbs, an immunochromatographic device was produced and shown in preclinical studies to detect, in inoculated saliva, all P. gingivalis laboratory strains and clinical isolates tested. The device was able to detect ≥1 × 105 P. gingivalis cells/mL. In a patient age- and sex-matched control clinical cohort, P. gingivalis levels in saliva-as measured by real-time polymerase chain reaction-positively correlated with P. gingivalis levels in subgingival plaque ( r = 0.819, P < 0.01) and clinical parameters of disease ( r = 0.633, P < 0.01). A positive device result strongly correlated with P. gingivalis levels >1 × 105 cells/mL in saliva ( r = 0.778, P < 0.001) and subgingival plaque ( r = 0.715, P < 0.001) with sensitivity, specificity, positive/negative predictive values, and accuracy levels of 95.0%, 93.3%, 90.5%, 96.6%, and 94.0%, respectively. The device result also positively correlated ( r = 0.695, P < 0.01) with disease severity as measured by probing depth. Detection of P. gingivalis in saliva was found to be rapid, taking 3 min from sample collection.

The association between clinical periodontal parameters and free haem concentration within the gingival crevicular fluid: a pilot study.

OBJECTIVES: To investigate the concentration of local free haem in gingival crevicular fluid at periodontally healthy compared with diseased sites in relation to clinical periodontal parameters. The second objective is to investigate for any correlation between smoking and haem concentration. MATERIAL AND METHODS: Clinical parameters were recorded for two healthy and two diseased sites from 22 patients with untreated periodontitis. Gingival crevicular fluid samples were collected from the same sites. Haem assay analysis was undertaken to determine haem concentration at these sites. RESULTS: Gingival crevicular fluid haem concentration was higher at periodontally diseased sites compared to healthy sites (mean 46.6 ± 70.6 nM in healthy vs. 1116.6 ± 2007.0 nM in diseased sites, p < 0.001) and positively correlated with probing pocket depth, attachment level and radiographic bone loss. Gingival crevicular fluid haem concentration was higher in non-smokers compared with smokers. However, no significant difference in correlation between haem concentration and clinical parameters were seen between smokers and non-smokers (p > 0.3). CONCLUSION: The higher concentration of gingival crevicular fluid haem at diseased compared with healthy sites indicates that there is an association between increased levels of local free haem and periodontal disease. This may be through the pro-inflammatory actions of free haem. Further study on a larger scale is required to determine the influence of smoking between haem concentration and clinical parameters.

Diabetic and cardiovascular risk in patients diagnosed with periodontitis.

BACKGROUND: There are well-established associations between periodontitis and diabetes mellitus and cardiovascular disease (CVD). The literature suggests a reciprocal relationship between periodontitis and diabetes. This pilot study aimed to measure in individuals with moderate to severe periodontitis their diabetes and CVD risks. METHODS: Participants with a diagnosis of periodontitis were recruited from the Royal Dental Hospital of Melbourne. Casual blood glucose (CBG), total cholesterol (TC), HbA1c, blood pressure (BP), weight and height were measured for all study participants. RESULTS: Forty-two participants enrolled in our study out of 159 that were approached [mean age 51.3, 26 (61.9%) females]. Twenty-four (57.1%) patients were undiagnosed pre-diabetic and had an HbA1c of ≥5.7; three (7.15%) patients were undiagnosed diabetic with an HbA1c of ≥6.5. Fourteen (33.3%) patients were hypertensive (BP ≥140/90 mmHg) and 17 (40.5%) had hypercholesterolaemia (TC ≥5.5). Twelve (28.6%) patients were smokers and 24 (57.1%) had a blood mass index (BMI) above 25. Twenty-four (57.1%) patients were referred to their general practitioner due to elevated disease markers. CONCLUSIONS: This small study found a large proportion of patients with periodontitis had undiagnosed pre-diabetes or diabetes, hypertension, hypercholesterolaemia and elevated BMI levels.

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.

Minimum intervention dentistry: periodontics and implant dentistry.

This article will look at the role of minimum intervention dentistry in the management of periodontal disease. It will discuss the role of appropriate assessment, treatment and risk factors/indicators. In addition, the role of the patient and early intervention in the continuing care of dental implants will be discussed as well as the management of peri-implant disease.

Mass spectrometric analysis of gingival crevicular fluid biomarkers can predict periodontal disease progression.

BACKGROUND AND OBJECTIVE: Gingival crevicular fluid has been suggested as a possible source of biomarkers for periodontal disease progression. This paper describes a technique for the analysis of gingival crevicular fluid from individual sites using mass spectrometry. It explores the novel use of mass spectrometry to examine the relationship between the relative amounts of proteins and peptides in gingival crevicular fluid and their relationship with clinical indices and periodontal attachment loss in periodontal maintenance patients. The aim of this paper was to assess whether the mass spectrometric analysis of gingival crevicular fluid may allow for the site-specific prediction of periodontal disease progression. MATERIAL AND METHODS: Forty-one periodontal maintenance subjects were followed over 12 mo, with clinical measurements taken at baseline and every 3 mo thereafter. Gingival crevicular fluid was collected from subjects at each visit and was analysed using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Samples were classified based upon pocket depth, modified gingival index (MGI), plaque index and attachment loss, and were analysed within these groups. A genetic algorithm was used to create a model based on pattern analysis to predict sites undergoing attachment loss. RESULTS: Three hundred and eighty-five gingival crevicular fluid samples were analysed. Twenty-five sites under observation in 14 patients exhibited attachment loss of > 2 mm over the 12-mo period. The clinical indices pocket depth, MGI, plaque levels and bleeding on probing served as poor discriminators of gingival crevicular fluid mass spectra. Models generated from the gingival crevicular fluid mass spectra could predict attachment loss at a site with a high specificity (97% recognition capability and 67% cross-validation). CONCLUSIONS: Gingival crevicular fluid mass spectra could be used to predict sites with attachment loss. The use of algorithm-generated models based on gingival crevicular fluid mass spectra may provide utility in the diagnosis of periodontal disease.

Left-to-right distribution of periodontal disease.

AIM: Symmetry is a property established in many human biological systems and it is reasonable to expect that it may also exist in the mouth. The objective of this study was to examine whether there is a similar left-to-right distribution in periodontal disease. METHOD: Records of 197 patients from the Periodontics department of The Royal Dental Hospital of Melbourne were analysed. The clinical parameters recorded were pocket probing depth, recession, bleeding on probing, mobility and furcation involvement. RESULTS: The average age of our sample group was 47.5 years old, with 34.5% men and 65.5% women. The results demonstrated significant left-to-right distribution with all the periodontal indices recorded. CONCLUSION: The findings support previous studies that show that a similar left-to-right distribution exists in the population studied.

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.

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.

Factors influencing the diagnosis and treatment of periodontal disease by dental practitioners in Victoria.

BACKGROUND: Healthy periodontal tissues are essential to overall dental health. Therefore, the detection and management of periodontal disease is an integral part of general dental practice. The aim of this study was to investigate confidence in diagnosis and management of periodontal disease by general dental practitioners (GDPs), assess if the Dental Practice Board guidelines on periodontal record keeping are being addressed, and, if necessary, try to find ways of improving the periodontal knowledge of GDPs. METHODS: A survey assessing practitioner confidence in diagnosing and treating periodontal disease was sent to a random selection of 550 dental care providers registered with the Dental Practice Board of Victoria. RESULTS: Two hundred and eighty five (51.8 per cent) of questionnaires were returned completed. It was found that 79.7 per cent of the sampled population screened all new patients for periodontal disease. The majority of respondents felt confident to diagnose and treat gingivitis and initial periodontitis. However, only 61.9 per cent felt confident to diagnose aggressive/early onset periodontitis, and many were not confident in treating advanced periodontitis (36.3 per cent) or aggressive periodontitis (51.6 per cent). The majority of dentists reported that they provided most of the non surgical periodontal therapy to their patients, while most surgical treatments were referred to specialist periodontists. Factors deemed to be important in influencing the decision to provide periodontal treatment included level of training and ability to motivate patients to improve oral hygiene. Many responents requested periodontic continuing education (CE) courses be run. CONCLUSIONS: Most of the dentists surveyed were confident to diagnose periodontal disease and to treat the more common presentations of periodontal disease. There is some evidence to suggest that some practitioners are not following the minimum requirements set by the Dental Practice Board of Victoria in relation to periodontal record keeping. The results also indicate a need for more periodontic CE courses in Victoria.

Clinical and microbiological effect of scaling and root planing in smoker and non-smoker chronic and aggressive periodontitis patients.

OBJECTIVES: To compare the effects of scaling and root planing (SRP) on clinical and microbiological parameters at selected sites in smoker and non-smoker chronic and generalized aggressive periodontitis patients. MATERIALS AND METHODS: Clinical parameters including probing depth (PD), relative attachment level (RAL), and bleeding upon probing (BOP), and subgingival plaque samples were taken from four sites in 28 chronic periodontitis (CP) and 17 generalized aggressive periodontitis (GAgP) patients before and after SRP. Polymerase chain reaction assays were used to determine the presence of A. actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythensis, Prevotella intermedia and Treponema denticola. RESULTS: Both CP and GAgP non-smokers had significantly greater reduction in pocket depth (1.0+/-1.3 mm in CP smokers versus 1.7+/-1.4 mm in non-smokers, p=0.007 and 1.3+/-1.0 in GAgP smokers versus 2.4+/-1.2 mm in GAgP non-smokers, p<0.001) than respective non-smokers, with a significant decrease in Tannerella forsythensis in CP sites (smokers 25% increase and non-smokers 36.3% decrease, p<0.001) and Prevotella intermedia at GAgP sites (smokers 25% reduction versus 46.9% in non-smokers, p=0.028). CONCLUSION: SRP was effective in reducing clinical parameters in both groups. The inferior improvement in PD following therapy for smokers may reflect the systemic effects of smoking on the host response and the healing process. The lesser reduction in microflora and greater post-therapy prevalence of organisms may reflect the deeper pockets seen in smokers and poorer clearance of the organisms. These detrimental consequences for smokers appear consistent in both aggressive and CP.

Changes in gingival crevicular fluid matrix metalloproteinase-8 levels during periodontal treatment and maintenance.

OBJECTIVES: The aim of this study was to investigate the effect of scaling and root planing (SRP) and the maintenance phase of treatment on the gingival crevicular fluid (GCF) matrix metalloproteinase-8 (MMP-8) levels. MATERIALS AND METHODS: Clinical measurements and GCF samples were taken from four sites in 20 adult periodontitis patients before and after SRP and during a 3-month maintenance phase of treatment. MMP-8 levels were measured from GCF samples by time-resolved immunofluorometric assay (IFMA) with monoclonal antibodies. RESULTS: SRP improved the clinical indices as would be predicted, 6.1 mm (SD = 1.4) at baseline compared with 4.3 mm (SD = 1.6) post-treatment (P < 0.001). Attachment level (AL) reduced but not significantly between these two visits 13.4 mm (SD = 2.4) compared with 12.8 mm (SD = 2.4) (P < 0.08) post therapy. GCF MMP-8 levels reduced after initial treatment from 33.8 micro g/30 s sample to 23.5 micro g/30 s, which just failed to reach statistical significance (P = 0.07). However, when MMP-8 levels were expressed as a concentration, the differences following initial therapy were significant (54.1 ng/ micro L at baseline compared with 34.2 ng/micro L post treatment; P < 0.005). The difference, however, between the baseline MMP-8 levels (33.8 ng/30 s) and the final visit (16 ng/30 s) following maintenance was markedly significant (P < 0.001) for both absolute amounts and on a concentration basis. CONCLUSION: In conclusion, clinical improvement following SRP was associated with significant reductions in MMP-8 levels. The GCF concentration of MMP-8 decreased after initial therapy but reduced even more dramatically (approximately 50%) following a 3-month period of maintenance (P < 0.001).

Changes in subgingival microflora and humoral immune response following periodontal therapy.

OBJECTIVES: To investigate the effect of scaling and root planing (SRP) on the microflora and humoral immune response in adult periodontitis. MATERIALS & METHODS: Clinical measurements, subgingival plaque samples, gingival crevicular fluid and sera were taken from 4 sites in 28 adult periodontitis patients before and after SRP. Polymerase chain reaction was used to determine the presence of A. actinomycetemcomitans, P. gingivalis, B. forsythus, P. intermedia, and T. denticola. ELISA was used to investigate the systemic and local antibody titres to these organisms, and thiocyanate dissociation for the determination of serum antibody avidity. RESULTS: SRP produced a good clinical improvement. On a subject basis there was little significant change in the microflora. However, on a site basis, there were significant reductions in P. intermedia, B. forsythus and T. denticola. There was little change in systemic and local antibody titres following SRP, although there was a significant reduction in antibody avidity to P. gingivalis and P. intermedia CONCLUSION: Post-therapy clinical improvement was associated with a reduction in bacterial prevalence, but statistical significance was only reached at a site level and this microbial reduction was not significant for all organisms. No significant post-therapy effects on the humoral immune response were noted other than a reduced antibody avidity to P. gingivalis and P. intermedia. The lack of a clear pattern in the humoral immune response may reflect a failure of the host response to produce adequate levels of biologically functional antibodies, and complex interactions between the subgingival flora and the host response.

Microbial comparison of smoker and non-smoker adult and early-onset periodontitis patients by polymerase chain reaction.

A number of bacterial species are involved in the aetiology of periodontitis and include Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus and Treponema denticola. Several studies have shown differences in the microflora between the various forms of periodontal disease. It is recognised that smoking is a risk factor for periodontal disease, but there are conflicting reports on whether or not smoking has an effect on the periodontal microflora. We utilised the polymerase chain reaction to determine the presence of A. actinomycetemcomitans, P. gingivalis, P. intermedia, B. forsythus and T. denticola in subgingival plaque samples in 33 adult periodontitis (AP) patients and 24 generalized early-onset periodontitis (GEOP) patients prior to treatment. When GEOP and AP patients were compared there were significant differences in the number of positive patients and sites for both A. actinomycetemcomitans and B. forsythus (p=0.0023 and 0.00001, respectively). No statistically significant differences in the prevalence of these organisms were found between smoker and non-smoker groups. These results confirm that AP and GEOP sites harbour varied microflora, but show that B. forsythus and A. actinomycetemcomitans were detected to a significantly greater extent in this group of GEOP than in the AP patients investigated. Our findings do not support the hypothesis that smokers have significant differences in the prevalence of periodontal pathogens from non-smokers.