The mechanical control of supragingival biofilm is accepted as one of the most important measures to treat and prevent dental caries and periodontal diseases. Nevertheless, maintaining dental surfaces biofilm-free is not an easy task. In this regard, chemical agents, mainly in the form of mouthwashes, have been studied to help overcome the difficulties involved in the mechanical control of biofilm. The aim of this paper was to discuss proposals for the teaching of supragingival chemical control (SCC) in order to improve dentists' knowledge regarding this clinical issue. Firstly, the literature regarding the efficacy of antiseptics is presented, clearly showing that chemical agents are clinically effective in the reduction of biofilm and gingival inflammation when used as adjuvant agents to mechanical control. Thus, it is suggested that the content related to SCC be included in the curricular grid of dental schools. Secondly, some essential topics are recommended to be included in the teaching of SCC as follows: skills and competencies expected of a graduate dentist regarding SCC; how to include this content in the curricular grid; teaching-learning tools and techniques to be employed; and program content.

The decay of beam-generated Langmuir wave into another Langmuir wave and an ion-acoustic wave is a well-known problem with wide-ranging applications. However, most discussions in the literature are based upon simple one-dimensional approximation. Recently, the present authors carried out a fully self-consistent two-dimensional analysis of the beam-driven Langmuir wave decay problem. The main focus of the present authors' work to date had been on the nonlinear evolution of Langmuir turbulence and its influence on the electrons. Relatively little attention had been paid to the ion-acoustic wave generation. In the present discussion, the focus is placed on the dynamics of ion-acoustic turbulence that results from the decay of beam-generated Langmuir wave. The present analysis considers three electron components, the dense core, a primary beam and a counter-streaming beam. We find that the ion-sound turbulence level sensitively depends on the properties of the counter-streaming beam.

BACKGROUND: The aim of the present study was to evaluate the association among menopause, hormone replacement therapy (HRT), and periodontal attachment loss (PAL). METHODS: Three hundred twenty-eight women (40 to 69 years old) who participated in a previous oral survey in South Brazil were included. Women who reported not having their monthly menstrual cycles for >or=12 months were classified as postmenopausal. Postmenopausal women were categorized according to HRT. Women with >or=30% teeth with PAL >or=5 mm were classified as having periodontitis. The data were analyzed using a multivariable logistic regression model and adjusted for age, smoking, socioeconomic status, and dental care. RESULTS: The prevalence of periodontitis was significantly greater among postmenopausal women not using HRT (HRT-) than among premenopausal women (64.4% versus 46.3%; P = 0.005). Similarly, the multivariable analysis demonstrated a significantly higher chance of having periodontitis in postmenopausal HRT- women than in premenopausal women (odds ratio [OR], 2.1; 95% confidence interval [CI]: 1.1 to 4.0). In contrast, no significant differences were observed in the prevalence of periodontitis between postmenopausal women using HRT (HRT+) and premenopausal women (48.8% versus 46.3%; P = 0.77). After adjusting for cofactors, postmenopausal HRT+ women did not have a greater likelihood of having periodontitis than premenopausal women (OR, 1.2; 95% CI: 0.6 to 2.5). No significant differences in tooth loss were observed among the study groups after adjusting for confounders. CONCLUSIONS: Postmenopausal HRT- women had a greater chance of having periodontitis than premenopausal women. In contrast, postmenopausal HRT+ women and premenopausal women had similar periodontal status. HRT may have a beneficial effect on periodontal health.