Prevalence and caries-related risk factors in schoolchildren of 12- and 15-year-old: a cross-sectional study.

BACKGROUND: To assess the prevalence and severity of caries in 12- and 15-year-old schoolchildren, and to analyse the related risk factors. METHODS: We conducted a cross-sectional study on a random sample of 1843 schoolchildren aged 12 and 15 from Galicia (northwest of Spain). Self-administered questionnaire and dental clinical examination were performed to obtain information about oral health habits, dental caries and oral hygiene. A logistic regression model including dental-caries-related variables was generated for each age group. RESULTS: The respective findings for 12- and 15-years-old were as follows: decayed, missing, filled teeth index both for permanent and temporary dentition (DMFT/dmft) of 0.89 (95% CI, 0.87-0.91) and 1.38 (95% CI, 1.33-1.43), respectively; caries prevalence 39.6% (95% CI, 36.3-42.9) and 51.7% (95% CI, 48.0-55.4), respectively. In the 12-year-old group, individuals who occasionally, never or hardly ever brushed their teeth had higher values of caries (OR = 1.83, 95% CI 1.07-3.15, and OR = 9.14, 95% CI1.63-51.17, respectively). Also, the presence of plaque on more than 1/3 gingival was statistically associated with an increase of caries (OR = 2.03; 95% CI, 1.11-3.70), and living in a rural environment was a risk factor (OR = 1.3; 95% CI,1.02-1.80). In the 15-year-old group, higher caries risk was found when brushing was performed once a day (OR = 1.61; 95% CI,1.03-2.50), and among individuals who visited private clinics (OR = 1.77; 95% CI, 1.17-2.66), while electric toothbrush was associated with a lower caries risk (OR = 0.50; 95% CI, 0.29-0.86). CONCLUSIONS: This study revealed that risk factors of dental caries showed differences in schoolchildren of 12- and 15-year-old. Strongest evidence related to caries in 12-year-old group were found in frequency of toothbrushing and dental plaque. In 15-year old group, electric toothbrush, time since the last visit to the dentist and type of dental care (public/private) had a stronger association with dental caries. Caries prevalence and mean DMFT/dmft increased from 12- to 15-year-old, in spite of improvement in oral hygiene at the age of 15.

Effects of nefazodone on the immune system of mice.

Mice exposed to a chronic auditory stressor and treated with nefazodone (10 mg/kg/day s.c.), showed a reduction in stress-induced suppression of thymus and spleen cellularity, and in peripheral T-Iymphocyte population. The in vitro blastogenic response of spleen lymphoid cells to mitogen concanavalin A, the in vitro and in vivo activity of phagocytosis, both measured using the zymosan and carbon clearance tests, respectively, were also assessed and nefazodone was found to partially reverse the inhibitory effect of stress on those parameters. Nefazodone did not significantly affect those parameters in unstressed mice. In conclusion, this report provides evidence on the immunoprotective effects of this novel antidepressant drug against the adverse effects of stress in mice.

Stimulatory effects of amphetamine on the development of Walker-256 carcinoma lung metastases in rats.

Experiments were performed in order to evaluate the effects of amphetamine (0.4 mg/kg/day) on the development of lung metastases in rats injected i.v. with 10(4) Walker 256 (W-256) carcinosarcoma cells, The number of metastatic nodules on the surface of the lungs, as well as the percentage-area of metastases in the frontal section through pulmonary hilus were increased in rats injected with amphetamine in comparison with those injected with placebo. Survival periods were also assessed and amphetamine was found to increase the lethality of rats.

Effects of amphetamine on the development of Moloney sarcoma virus-induced tumors in mice.

Experiments were conducted to evaluate the effects of amphetamine (0. 4 mg/kg) on the development of autochthonous tumors induced by the Moloney sarcoma virus (MSV) in Balb/c female mice. Enhancement of MSV-induced tumor incidence and tumor growth was observed, together with a delay in the usual prompt regression of the tumors, when mice were daily injected with amphetamine for 3 days after MSV-inoculation. However, no effects of amphetamine on tumor development were observed when it was administered during the 3 days before tumor inoculation.

Effects of amphetamine on cell mediated immune response in mice.

Mice injected with amphetamine showed a dose-related suppression of the natural killer cell activity. The capacity of T-cells to generate cytotoxic T-lymphocytes (CTL) in mixed lymphocyte cultures and in vivo was also assayed and amphetamine was found to inhibit CTL responses.

Effects of alprazolam on the free-choice ethanol consumption induced by isolation stress in aged rats.

Late-onset drinking is a common problem in elderly people related to stress induced by social isolation. Experiments were performed in order to evaluate the effects of alprazolam, a benzodiazepine agonist anxiolytic, on the free-choice ethanol consumption in aged rats subjected to isolation stress. The animals we offered a two-bottle choice consumption (one of 0.2% saccharin and the other with 10% ethanol/0.2% saccharin) and then exposed to 4 days of isolation stress on an irregular, unpredictable schedule. Stress resulted in significant increase in ethanol consumption. Treatment with alprazolam (1 mg/Kg) partially reversed this adverse effect of stress.

Effects of fluoxetine on the development of lung metastases induced by operative stress in rats.

Experiments were performed in order to evaluate the effects of fluoxetine, a selective inhibitor of neural serotonin transporter antidepressant, on the development lung metastases in rats subjected to laparotomy and injected (i.v.) with 10(4) Walker 256 (W-256) carcinosarcoma cells. The number of metastatic nodules on the surface of the lungs, as well as the percentage-area of metastases in the frontal section through pulmonary hilus were increased in rats subjected to sham-surgery or laparotomy. Treatment with fluoxetine (5 mg/kg) partially reversed those adverse effects of surgery, but the difference was clearer when it was administered before surgery was performed. Survival periods were also assessed and fluoxetine was found to decrease the lethality of rats exposed to surgery.

Effects of psychological stress and alprazolam on development of oral candidiasis in rats.

Psychological stress has been found to suppress cell-mediated immune responses that are important in limiting the proliferation of Candida albicans. Since anxiolytic drugs can restore cellular immunity in rodents exposed to stress conditions, we designed experiments conducted to evaluate the effects of alprazolam (1 mg/kg of body weight/day), a central benzodiazepine anxiolytic agonist, on the development of oral candidiasis in Sprague-Dawley rats exposed to a chronic auditory stressor. Animals were submitted to surgical hyposalivation in order to facilitate the establishment and persistence of C. albicans infection. Application of stress and treatment with drugs (placebo or alprazolam) were initiated 7 days before C. albicans inoculation and lasted until the end of the experiments (day 15 postinoculation). Establishment of C. albicans infection was evaluated by swabbing the inoculated oral cavity with a sterile cotton applicator on days 2 and 15 after inoculation, followed by plating on YEPD (yeast extract-peptone-dextrose) agar. Tissue injury was determined by the quantification of the number and type (normal or abnormal) of papillae on the dorsal tongue per microscopic field. A semiquantitative scale was devised to assess the degree of colonization of the epithelium by fungal hyphae. Our results show that stress exacerbates C. albicans infection of the tongues of rats. Significant increases in Candida counts, the percentage of the tongue's surface covered with clinical lesions, the percentage of abnormal papillae, and the colonization of the epithelium by fungal hyphae were found in stressed rats compared to those found in the unstressed rats. Treatment with alprazolam significantly reversed these adverse effects of stress, showing that, besides the psychopharmacological properties of this anxiolytic drug against stress, it has consequences for Candida infection.