Prostaglandin-endoperoxide synthase (PTGS2) and Defensin beta 1 (DEFB1) gene polymorphisms are not associated with periodontitis in Malays.

INTRODUCTION: In line with the association of prostaglandin-endoperoxide synthase 2 (PTGS2) and defensin beta 1 (DEFB1) single nucleotide polymorphisms (SNPs) with periodontitis among the Chinese and European populations, the current study was aimed to assess the same association among the Malays in Malaysia. METHODS: Blood samples of individuals with periodontitis (PD) (n=72) and periodontally healthy (PH) (n=62) donors were obtained from Malaysian Periodontal Database and Biobanking system (MPDBS). Genomic DNA samples were analyzed for three PTGS2 SNPs (rs5275, rs20417, rs689466,) and one DEFB1 SNP (rs1047031) using Taqman SNP genotyping assays. Notably, rs20417 and rs689466 were located in the promoter region while rs5275 and rs1047031 were located in the 3' untranslated region of the transcript. Association between the SNPs and PD were then analyzed using genotypic association analysis (additive, dominant and recessive models). RESULTS: The allelic frequency for the rs689466-G was higher in PD group (35.2%) compared that in PH group (29.0%). However, the association of rs689466-G and other SNPs with PD was not statistically significant (at 95% CI). No associations were observed for genotypic associations between the PTGS2 and DEFB1 SNPs with PD susceptibility. CONCLUSIONS: PTGS2 (rs5275, rs20417, and rs689466) and DEFB1 (rs1047031) polymorphism was not associated with PD in Malays, unlike the Chinese, Taiwanese & European population. This suggests that other causal variants might be involved in the development and progression of PD among Malays.

Alcohol consumption is associated with periodontitis. A systematic review and meta-analysis of observational studies.

OBJECTIVE: To determine whether alcohol consumption is associated with the risk of periodontitis. BASIC RESEARCH DESIGN: Systematic review and meta-analysis of observational studies performed using the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. METHOD: PubMed and Scopus were searched for eligible articles published in English from inception till November 2018. The quality of studies was assessed by the Newcastle Ottawa Scale. Pooled odds ratios (OR) and 95% confidence intervals (CI) were calculated for the risk of periodontitis associated with highest versus lowest/non-alcohol in a random effects meta-analysis model. Heterogeneity and sensitivity were investigated in meta regression analysis. A funnel plot was used to assess publication bias. RESULTS: Twenty-nine observational studies were included. One study with two separate datasets was considered as two separate studies for analysis. Alcohol consumption was significantly associated with the presence of periodontitis (OR = 1.26, 95% CI= 1.11-1.41). Significant heterogeneity (I2=71%) was present in the overall analysis, primarily attributable to sampling cross-sectional studies (I2=76.6%). A funnel plot and Egger tests (p=0.0001) suggested the presence of publication bias. CONCLUSION: Alcohol consumption was associated with increased occurrence of periodontitis and should be considered as a parameter in periodontal risk assessment. Publication bias should be explored in future studies.

Impact of non-surgical periodontal therapy on OHRQoL in an obese population, a randomised control trial.

BACKGROUND: Oral Health Related Quality of Life (OHRQoL) is an important measure of disease and intervention outcomes. Chronic periodontitis (CP) is an inflammatory condition that is associated with obesity and adversely affects OHRQoL. Obese patients with CP incur a double burden of disease. In this article we aimed to explore the effect of Non-Surgical Periodontal Therapy (NSPT) on OHRQoL among obese participants with chronic periodontitis. MATERIALS AND METHODS: This was a randomised control clinical trial at the Faculty of Dentistry, University of Malaya. A total of 66 obese patients with chronic periodontitis were randomly allocated into the treatment group (n=33) who received NSPT, while the control group (n=33) received no treatment. Four participants (2 from each group) were non-contactable 12 weeks post intervention. Therefore, their data were removed from the final analysis. The protocol involved questionnaires (characteristics and OHRQoL (Oral Health Impact Profile-14; OHIP-14)) and a clinical examination. RESULTS: The OHIP prevalence of impact (PI), overall mean OHIP severity score (SS) and mean OHIP Extent of Impact (EI) at baseline and at the 12-week follow up were almost similar between the two groups and statistically not significant at (p=0.618), (p=0.573), and (p=0.915), respectively. However, in a within-group comparison, OHIP PI, OHIP SS, and OHIP EI showed a significant improvement for both treatment and control groups and the p values were ((0.002), (0.008) for PI), ((0.006) and (0.004) for SS) and ((0.006) and (0.002) for EI) in-treatment and control groups, respectively. CONCLUSION: NSPT did not significantly affect the OHRQoL among those obese with CP. Regardless, NSPT, functional limitation and psychological discomfort domains had significantly improved. TRIAL REGISTRATION: ( NCT02508415 ). Retrospectively registered on 2nd of April 2015.

Establishing and managing a periodontal biobank for research: the sharing of experience.

Periodontal bio-repositories, which allow banking of clinically validated human data and biological samples, provide an opportunity to derive biomarkers for periodontal diagnosis, prognosis and therapeutic activities which are expected to improve patient management. This article presents the establishing of the Malaysian Periodontal Database and Biobank System (MPDBS) which was initiated in 2011 with the aim to facilitate periodontal research. Partnerships were established with collaborating centres. Policies on specimen access, authorship and acknowledgement policies were agreed upon by all participating centres before the initiation of the periodontal biobank. Ethical approval for the collection of samples and data were obtained from institutional ethics review boards. A broad-based approach for informed consent was used, which covered areas related to quality of life impacts, genetics and molecular aspects of periodontal disease. Sample collection and processing was performed using a standardized protocol. Biobanking resources such as equipment and freezers were shared with the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). In the development of the MPDBS, challenges that were previously faced by the MOCDTBS were considered. Future challenges in terms of ethical and legal issues will be faced when international collaborations necessitate the transportation of specimens across borders.

Moving into a new era of periodontal genetic studies: relevance of large case-control samples using severe phenotypes for genome-wide association studies.

Studies to elucidate the role of genetics as a risk factor for periodontal disease have gone through various phases. In the majority of cases, the initial 'hypothesis-dependent' candidate-gene polymorphism studies did not report valid genetic risk loci. Following a large-scale replication study, these initially positive results are believed to be caused by type 1 errors. However, susceptibility genes, such as CDKN2BAS (Cyclin Dependend KiNase 2B AntiSense RNA; alias ANRIL [ANtisense Rna In the Ink locus]), glycosyltransferase 6 domain containing 1 (GLT6D1) and cyclooxygenase 2 (COX2), have been reported as conclusive risk loci of periodontitis. The search for genetic risk factors accelerated with the advent of 'hypothesis-free' genome-wide association studies (GWAS). However, despite many different GWAS being performed for almost all human diseases, only three GWAS on periodontitis have been published - one reported genome-wide association of GLT6D1 with aggressive periodontitis (a severe phenotype of periodontitis), whereas the remaining two, which were performed on patients with chronic periodontitis, were not able to find significant associations. This review discusses the problems faced and the lessons learned from the search for genetic risk variants of periodontitis. Current and future strategies for identifying genetic variance in periodontitis, and the importance of planning a well-designed genetic study with large and sufficiently powered case-control samples of severe phenotypes, are also discussed.