Aim: The purpose of this study was to determine theDNA yield and quality from different non-invasivesampling methods and to identify the method whichgave the highest DNA yield. Method: Thirty-eightvolunteers had been recruited in this study whereblood, buccal cells and saliva were collected usingvarious collection techniques. Buccal cells werecollected by 1) cytobrush and 2) saline mouth rinsingor “swish”. Meanwhile saliva was collected by passivedrooling method. Upon processing the white bloodcell (WBC), buccal cells and saliva samples, DNAextraction was performed according to themanufacturer’s protocol. Quantification and quality(DNA ratio at A260/A280) of the extracted DNA weredetermined using NanoDropND-1000®. T-test wasperformed to compare means between DNA obtainedfrom various collection methods. Results: DNA yieldsfrom buccal cells collected with cytobrush, “swish”,saliva and WBC (mean ± SD) were (8.2 ± 5.9)ng/μl,(28.2 ± 14.9)ng/μl, (5.9 ± 9.5)ng/μl and (105.3 ±75.0)ng/μl respectively. Meanwhile the mean DNAratio at A260/A280 for cytobrush, “swish”, saliva andWBC were 2.3, 2.0, 1.7 and 1.8 respectively. Post hoctest with Bonferroni correction suggested that DNAyield from “swish” technique exhibited the least meandifferent as compared to the DNA extracted from WBC(p<0.05). There was no significant difference in themean quality of the DNA extracted from WBC, salivaand buccal cells collected in these non-invasivemethods (p=0.323). Conclusion: The “swish”technique of obtaining buccal cells yielded thehighest amount of DNA and was of the quality of DNAextracted from blood sample.Key words: buccal cells; non-invasive methods;cytobrush; “swish”; saliva; DNA yield; DNA quality

Background: In an academic setting due to financialconstrain, it is not uncommon during non-surgicalprocedures dental students and clinical supervisorswash their gloved hands with disinfectants in betweenpatients or when touching on non-contaminatedobjects. Whether this practice could cause anydeterioration of the glove and expose clinicians andpatients to infectious micro-organisms was a concern.Aim: The aim of this study was to investigate the effectof multiple washes of gloved hands with a disinfectanton the integrity of the gloves. Methods: Three brandsof commonly used gloves in a dental school weretested for leaks after multiple washes with adisinfectant. Thirty pairs of each type of gloves weresubjected to 0, 1, 5, 10, 20 and 30 washes with adisinfectant solution at a 5-minute interval betweeneach wash. After each washing cycle, the gloves werefilled with 1L of water and hanged for 2 minutes toobserve any signs of water leaks. Results: The resultsshowed that the type of gloves and number of washeswere significantly associated with the leakage rates(p<0.001). Washing of gloves for more than 5 timeswere at least 6 times higher to suffer from leakage(OR=6.23, 95% CI=2.14–18.08). Powdered gloves werealmost 13 times higher to leak in all washes(OR=12.78, 95% CI= 4.40–37.14) and were almost 25times more likely to leak when washed for more than5 times (OR = 24.92, 95% CI = 5.79 – 107.21) whencompared to the non-powdered gloves. Conclusion:The practice of washing gloved hands with adisinfectant deteriorates the integrity of the gloves.

Objectives: This study aims to identify the relationship between dietary intakes of β-carotene with riskof oral cancer. Methods: A hospital-based, case-control study was conducted on 306 Malaysians whoseek treatment at participating centres/hospitals. Subjects selected from the Malaysian Oral Cancer Dataand Tissue Banking System (MOCDTBS) consisted of 153 cases and 153 controls that were matchedfor gender, age (±5 years) and ethnicity. Food consumption was measured using Food FrequencyQuestionnaire (FFQ). NutrieMart Version 2.0.0 software was used to estimate daily nutrient of eachsubject from the FFQ. Logistic Regression analysis was conducted to compute the odds ratio (OR) forintakes of β-carotene and oral cancer risk. Results: Intake of β-carotene was found to be not associatedwith risk of oral cancer (OR 0.83, 95%CI: 0.42-1.66, p>0.05). Conclusion: No significant associationwas found between dietary intakes of β-carotene with oral cancer risk in this study population.