The noise is defined as unwanted sound that causes discomfort and physical changes. This study was conducted to evaluate intensity of noise in the pediatric dental clinic and to investigate noise environment of a pediatric dentist. Human ear shaped microphone and mobile noise level meter were used for recording noise and calculating intensity of noise.
By recording according to the method specified by Korea Occupational Safety and Health Agency (KOSHA) of Korea Ministry of labor and employment, the following results were obtained. For 16 experimental days, 8 hour time weighted average (8hr-TWA) was 49.33 dBA (A-weighted deci-Bell) on daily average with maximum 58.54 dBA and minimum 33.97 dBA. And Dose was 0.49% on daily average with maximum 1.28%, minimum 0.04%. These values are less than criteria of KOSHA standard (85 dBA, 100%). Comparing the highest noise level for each patient, pulp therapy group and Frankel grade I group were the highest.
The intensity of dental noise of pediatric dental clinic didn’t meet standard of KOSHA. It is necessary to re-evaluate noise environment by establishing new standards considering environment of pediatric dental clinic.

Black staining of the teeth in children and adolescents does not cause pain or serious illness, but it can be socially debilitating for esthetic reasons. Black staining is easily removed through periodic professional mechanical tooth cleaning and ultrasonic scaling, but it can easily recur within few months. Using essential oil-containing mouth rinses diluted at 50% twice per day could prevent the black staining from returning after it is removed, reducing the need for mechanical treatments and improving esthetics.

Purpose: The standard of care for early rectal cancer is radical surgery; however, it carries high postoperative morbidity. This study aimed to assess the short-term and oncological outcomes of local excision and adjuvant radiotherapy in patients with high-risk pathological stage (p) T1 rectal cancer. Methods: Fifty-five patients underwent local excision with adjuvant radiotherapy or radical resection for high-risk T1 rectal cancer. Patients with adenocarcinoma within 10 cm from the anal verge; pT1 with high-risk features (grade 3–4); a tumor size of ≥3 cm; a positive margin; a lymphovascular or perineural invasion; or a submucosal invasion depth of ≥SM2 were included. Results: The rates of postoperative complications and stoma formation were higher in the radical surgery group (P = 0.021 and P = 0.003, respectively). No significant differences were observed in the overall survival and disease-free survival (DFS) between the 2 groups (P = 0.301 and P = 0.076, respectively). Vascular invasion was a significantly poor prognostic factor for DFS (P = 0.033). The presence of 3 or more high-risk features was associated with a poor DFS (P = 0.002). Conclusion Local excision with adjuvant radiotherapy significantly reduces the risk of complications and stoma formation. It is also an alternative option for patients with fewer than 3 high-risk features.