Dental caries, the most common oral disease, is a multifactorial disease caused by interactions among bacteria within the dental plaque, food, and saliva, resulting in tooth destruction. Streptococcus mutans has been strongly implicated as the causative organism in dental caries and is frequently isolated from human dental plaque. Photodynamic therapy (PDT) is a technique that involves the activation of photosensitizer by light in the presence of tissue oxygen, resulting in the production of reactive radicals capable of inducing cell death. Postantibiotic effect (PAE) is defined as the duration of suppressed bacterial growth following brief exposure to an antibiotic. In this study, the in vitro PAE of PDT using erythrosine and light emitting diode on S. mutans ATCC 25175 was investigated. The PAE of PDT for 1 s irradiation and 3 s irradiation were 1.65 h and 2.1 h, respectively. The present study thus confirmed PAE of PDT using erythrosine on S. mutans.

Laparoscopic appendectomy using three trocars has been widely performed. Recently, a single incision laparoscopic surgical procedure has become popular because it is less invasive. We report on our early experience in performance of single incision laparoscopic appendectomy (SIL-A). Data on the operating time, the duration to make the pneumoperitoneum, body mass index (BMI), rate of conversion to another operation, complication, hospital stay, dosage of analgesics, and pain score were collected prospectively at two centers. Twenty seven patients underwent SIL-A. The mean BMI was 23.3±3.1 kg/m2 (17.6-30.5). The mean time required to make a pneumoperitoneum was 9.9±5.0 minutes (5.0-28.0). The mean operating time was 37.6±26.7 minutes (10.0-100.0). The rate of intra-operative complication was 3.7% (1/27), and the rate of post-operative complication was 22.2% (6/27). The mean hospital stay was 4.1±1.2 days (2-6). The immediately postoperative pain score was 5.4±1.5 (3-8), however, the pain score at discharge was 0.4±0.7 (0-2). The mean dosage of analgesics was 1.5±1.3(0-4), however, none of the patients took analgesics after postoperative three days. SIL-A is feasible but requires improved instrumentation and experience.