Prior to the end of the 20th century, microorganism research was limited to culture and has since been revolutionized by genetic analysis. Microorganisms, including bacteria, can cause disease, but most of them are commensal microorganisms in our bodies. This knowledge changes the pathological approach to infectious diseases and lends to a new perspective on the effects of gut and oral microorganisms on disease and health. The oral cavity, particularly the periodontal pocket, is considered to be a reservoir of microbes that cause disease, and oral microbial control is becoming more important. In this review, I will examine the changes in the microbiological revolution and the meaning of oral healthcare management based on those changes.

The aim of this study was to evaluate the competency of the Easyperio test, a genetic test method based on real time PCR for the detection of bacteria that cause dental caries and periodontal disease. To verify the validity of this text, various dental health evaluations were administered to 33 boys between the ages of 12 to 14, as this age group commonly experiences dental caries. These evaluations included a dental caries experience survey, a first molar health evaluation, the Dentocult Streptococcus mutans (SM) strip mutans, the Dentocult Lactobacillus spp (LB) test, and the Easyperio test. The correlation coefficients between the level of the Dentocult SM strip mutans and the dental caries experience were DT (R=0.570, p=0.001), DMFT (R=0.376, p=0.031), and first molar health (R=-0.395, p=0.023). The correlation coefficients between the amount of SM in the Easyperio test and dental caries experience were DT (R=0.528, p=0.002), DMFT (R=0.369, p=0.035), and first molar health (R=-0.426, p=0.013). The correlation coefficients between the level of the dentocult SM strip mutans and the SM amounts of the Easyperio test were S.mi (R=0.564 p=0.001) and S.mu (R=0.621, p=0.002). The correlation coefficients between the level of the Dentocult LB test and the SM amount of Easyperio test was S.mi (R=0.495, p=0.003). In conclusion, Easyperio test may be an easy and effective method for the differentiation and diagnosis of dental caries through quantitative and qualitative analysis of oral bacteria.

The purpose of this study was to determine the level of toothbrush bacterial growth, whether the dryness of the toothbrush head differs depending on the number of holes in the head, and to use these results as a reference for future toothbrush design. Two-millimeter holes were created on the head of the toothbrushes in groups of three, one, or zero holes. We made the solution with Streptococcus mutans, and the toothbrushes were placed in the solution and agitated. The toothbrushes were shaken to remove moisture and allowed to air-dry. The toothbrush heads were swabbed with saline and then placed in two inoculation groups. The first group was inoculated with a 102 dilution of the S. mutans culture and the second was inoculated with the original culture. After incubation, bacterial colony numbers were measured. The number of holes on the toothbrush head correlated with a decrease in number of cultured bacterial colonies. Our model of a toothbrush head with holes indicated that these holes in the toothbrush head were effective in reducing the level of microbial contamination and that a greater number of holes creates an improved toothbrush sanitation effect. The average number of colonies on the head of toothbrush by number of holes was high, followed by the number of holes 0, 1 and 3, and the average number of colony among toothbrush heads was same. The use of a toothbrush with holes between the toothbrush head indicates that it is effective in reducing the level of microbial contamination between the toothbrush head and toothbrush and the higher the number of holes, the better the effect.

Halitosis is primarily caused by bacterial decay. The bacteria, which originate from biofilms such as dental plaque, show abnormal proliferation due to dental caries, periodontal diseases, soft tissue infections, and tongue diseases. Most studies on halitosis have exclusively focused on gram-negative bacteria in the oral cavity rather than on general oral microorganisms including oral fungi. This study analyzed oral fungal hyphae, as well as distribution and motility of oral microorganisms, and provided basic data on the control of halitosis. Our results revealed that the greater is the number of cocci bacteria, the higher is the halitosis value, or bad breath value (BBV), suggesting that cocci have a strongly positive correlation with halitosis (r=0.379, p=0.030). Moreover, there was no significant difference in the morphology or distribution of motile bacteria and motility score, with respect to BBV. Lastly, we investigated the relationship between halitosis and oral fungal hyphae. We found that a higher BBV corresponded with a greater number of fungal hyphae and that patients with fungal hyphae scored a higher BBV. However, this result was not statistically significant. In conclusion, this study provided the preliminary data on oral microorganisms and halitosis, but further studies are needed to analyze the relationship between oral microorganisms and halitosis.

This study aimed to assess dental hygiene students' and other medical personnel's knowledge of dental hygienists' legal responsibilities. A self-reported questionnaire was conducted for 2 weeks from March 25 to April 9, 2017. One of the main questions focused on the legal scope of practice for dental hygienists according to current medical technicians. A total of 298 subjects' responses were analyzed. We found that 62.1% of the respondents were aware of dental hygienists' legal responsibilities. Of the dental hygiene students surveyed, 93.6% replied that they were aware of other medical personnel's expectations. Responses to 12 legal questions were shown to have different distributions depending upon the level of dental hygienist education. Overall, knowledge of dental hygienist legal responsibilities was more comprehensive for senior students in each legal topic. However, few students (1.7%) answered all 12 legal questions correctly. In conclusion, dental hygiene students' awareness of their profession's legal scope should be improved. In addition, the Korean Dental Hygienists Association needs to more actively promote understanding of the profession's legal scope as well as of medical personnel's expectations of dental hygienists' legal roles.

Online data can be explored for topics browsed by an unspecified population to detect professional information demands more quickly. The purpose of this study was to collect and analyze online questionnaires in order to find information required by dental hygienists. We analyzed the frequency of posting words after isolating nouns from questions of the Korean Dental Hygienists Association homepage's Q & A section, the Naver Knowledge-iN service, and a dental hygienists' online meeting site in Naver. We found that queries of the Korean Dental Hygienists Association's homepage were concentrated on education renewal and license notification. The queries about dental hygienists in the Naver Knowledge-iN service used words related to job or career choice, and the queries of the dental hygienist-affiliated site had many words related to dental practice, dental work, and turnover. This study showed that the information needs of unspecified dental hygienists varied depending on the online environment such as homepage, blog, and information service.