This study was conducted in order to identify the literature on oral health status and health-related QOL, review the findings systematically, and assess the association between them. We performed a literature search of reports published between January 1973 and June 2004, using five databases including MEDLINE. Only studies that used validated generic health-related QOL instruments were selected. The reviewers evaluated selected articles independently and resolved disagreements by consensus. A total of 1,726 articles were retrieved and seven were selected for the review; five observational studies and two intervention studies. Four studies showed significant associations between oral health status and health-related QOL. Temporomandibular disorders were highly associated with reduced health-related QOL. Poor oral status linked to both craniomandibular and cervical spinal pain was associated with increased impairment of health-related QOL. Dissatisfaction with the teeth and mouth, and a sensation of dry mouth contributed to reduce health-related QOL. Providing edentulous patients with implant-supported full dentures contributed to improve health-related QOL. Assessment of health-related QOL in relation to oral health with validated instruments remains insufficient. The present findings suggest that oral health status could affect health-related QOL in some settings; however, further evidence is needed to support this interpretation. (J. Oral Sci. 48, 1-7, 2006)

The purpose of this study was to determine the usefulness of salivary biochemical markers for the screening of periodontal disease and examine the agreement between the results of saliva enzyme tests and those of probing depth. The present study included a total of 187 subjects who underwent annual medical check-ups at the Comprehensive Health Care Center, Honjo, Saitama Prefecture, Japan. Periodontal pocket probing was performed with a WHO probe, and various enzymes and biochemical parameters in saliva were measured. For lactate dehydrogenase (LDH), the proportions of the five isoenzymes were calculated. To decide the cut-off point for each enzymatic activity, receiver operating characteristic curves (ROC curves) were constructed and the points of minimum difference between sensitivity and specificity were decided. Among the biochemical markers tested, salivary LDH level had the highest sensitivity and specificity (sensitivity 0.66, specificity 0.67), while salivary levels of aspartate aminotransferase (AST) and blood urea nitrogen (BUN) also had sensitivity and specificity above 0.60. Among the LDH isoenzymes, LDH4 and LDH5 dominated in whole saliva samples. Salivary LDH may be a feasible and useful parameter for the screening of periodontal disease, while salivary AST and BUN also appear to be potentially useful for this purpose. (J. Oral Sci. 48, 177-183, 2006)

The oral cavity in healthy subjects has a well-balanced microbiota that consists of more than 700 species. However, a disturbance of this balance, with an increase of harmful microbes and a decrease of beneficial microbes, causes oral disorders such as periodontal disease or dental caries. Nowadays, probiotics are expected to confer oral health benefits by modulating the oral microbiota. This study screened new probiotic candidates with potential oral health benefits and no harmful effects on the oral cavity. We screened 14 lactobacillus strains and 36 streptococcus strains out of 896 oral isolates derived from healthy subjects. These bacteria did not produce volatile sulfur compounds or water-insoluble glucan, had higher antibacterial activity against periodontal bacteria, and had higher adherence activity to oral epithelial cells or salivary-coated hydroxyapatite in vitro. We then evaluated the risk of primary cariogenicity and infective endocarditis of the selected oral isolates. As a result, Lactobacillus crispatus YIT 12319, Lactobacillus fermentum YIT 12320, Lactobacillus gasseri YIT 12321, and Streptococcus mitis YIT 12322 were selected because they showed no cariogenic potential in an artificial mouth system and a lower risk of experimental infective endocarditis in a rat model. These candidates are expected as new probiotics with potential oral health benefits and no adverse effects on general health.

Periodontal screening plays an important role in the prevention of periodontal disease and promotes an improvement in oral health-related quality of life. The World Health Organization’s Community Periodontal Index should be carried out by well-trained dentists. However, the Community Periodontal Index is an invasive technique, and if used for periodontal screening, increases the cost of evaluation. In order to overcome these issues, we developed saliva tests for periodontal screening. The purpose of this study was to calculate the sensitivity and specificity of our method for measuring hemoglobin and lactate dehydrogenase levels in saliva. Inclusion criteria were adults aged over 20 years with at least 20 teeth remaining. The study population comprised 38 men and 54 women with a mean age of 50.03 years. Oral examinations were carried out by dentists, and the number of remaining teeth, presence or absence of calculus, bleeding on probing and pocket depth were recorded. In this study, periodontitis was defined according to the criteria of the Center for Disease Control and Prevention in partnership with the American Academy of Periodontology. In order to examine hemoglobin and lactate dehydrogenase levels in saliva, participants were instructed to chew on a standard-sized tasteless and odorless gum base for 5 min, during which time, stimulated whole saliva was continuously collected. The sensitivity and specificity for hemoglobin levels were 0.759 and 0.763, respectively, and 0.722 and 0.711, respectively, for lactate dehydrogenase levels. Combining these two tests, when samples tested positive for both hemoglobin and lactate dehydrogenase, the positive predictive value was 91.7 %. Measuring hemoglobin and lactate dehydrogenase levels in saliva is a less invasive method than the Community Periodontal Index. Therefore, our saliva tests may be a viable alternative to the Community Periodontal Index for periodontal screening.