Effect of long term 900 MHz radiofrequency radiation on enamel microhardness of rat's teeth.

PURPOSE: Oral tissues are important parts of body that absorbs radiation emitted from mobile phones which is the most popular technological equipment in the world. Because of the limited studies in this field, we aimed to investigate the effect of Radio Frequency (RF) radiation emitted from 900 MHz mobile phones on the enamel micro hardness of rat teeth. MATERIALS AND METHODS: The study was carried out on twenty one Wistar Albino adult male rats which were divided into two groups such as control and experiment groups. For the study group (n: 14), rats exposed to the radiation 2 h per day (7 days in a week) for 10 months. For the control group (n: 7), rats were placed into the carousel and the same procedure was applied except that the generator was turned off. At the end of the study, enamel micro hardness of rat's teeth was measured. RESULTS: The results of this study showed that 900 MHz RF radiation did not alter the enamel micro hardness of rats' teeth (p>0.05). CONCLUSIONS: Exposure of 900 MHz RF radiation for 2 hours per day during ten months does not alter enamel micro hardness of rats' teeth. However, further studies are necessary to clarify this topic.

Incidence and prevention of traumatic injuries in paediatric handball players in Istanbul, Turkey.

AIM: To investigate the frequency of dental injuries in paediatric handball players. In addition, the players' habits with regard to mouthguard usage, as well as their general knowledge of the prevention of traumatic dental injuries (TDIs) were investigated. Data were collected by structured one-to-one interviews with children of 14 randomly selected handball teams in the amateur national league. METHODS: The questionnaire consisted of 15 questions. The age, gender, trauma experience and league status of each interviewee was recorded. The interviews took place mainly at national championships or tournaments. RESULTS: A total of 212 individuals, 74 girls and 138 boys, were interviewed. Forty-one of the 212 participants (19.3 %) had sustained a dental injury. The mean age of participants was 12 ± 1.6 years. Concussion was the most frequent finding and the cause of injury was a blow from another player. The number of individuals that were aware of mouthguards was only 15.6 % and surprisingly no players used mouthguards. CONCLUSIONS: The results show that handball players need more knowledge and education considering the prevention of TDIs from their sports clubs and dentists. The importance of adequate facial protection in contact sports should be endorsed by all sports clubs, and parents advised accordingly.

The effect of laser-activated Acidulated Phosphate Fluoride on enamel submitted to erosive solution only: an in vitro preliminary evaluation.

AIM: The purpose of this in vitro study was to evaluate the potential effect of laser therapy on the prevention of erosive demineralisation either alone or combined with acidulated phosphate fluoride gel on human enamel. It was hypothesized that such a treatment would decrease enamel solubility. STUDY DESIGN: Efficacy of 2940 nm Er:YAG laser with preset parameters--alone or combined with APF (Acidulated Phosphate Fluoride) gel--was tested on freshly extracted human permanent molars. MATERIALS AND METHODS: Ten sound human third molars were sectioned into 5 surfaces (2 x 3 mm) with hard tissue microtome and were randomly allocated into different treatment groups as follows. The Vicker's hardness of each surface was obtained at the baseline. Group 1, negative control group: no treatment. Group 2, positive control group: only 1.23% APF gel (Denti-Care gel, Medicom) 1 minute application. Group 3: irradiated with surface modification mode (2940 nm, 1.2j/cm², 10 Hz, 300 µm) Er:YAG laser. Group 4: Er:YAG laser application following 1.23% APF gel. Group 5: 1.23% APF gel following Er:YAG laser application. The demineralisation process was obtained by immersion of specimens in a soft drink for 10 minutes and then the Vickers hardness was reevaluated. STATISTICS: For statistical analyses within groups the Kruskal Wallis test was used, while for comparing groups the paired sample t test (significance p<0.05) was used. RESULTS: The difference in microhardness values of each group obtained following the treatments was not statistically significant (p>0.05). Beside, no statistical difference was found in Vickers value related to the application of fluoride prior or after laser therapy. Conclusion Er:YAG laser irradiation alone or combined with APF decreased the enamel solubility but combined treatment did not show any significant additional effect.