Influential variables in the Journal Impact Factor of Dentistry journals.

OBJECTIVE: The aim of this contribution is to determine what variables influence the position, by quartiles of the impact factor, as a quality indicator of a journal in the field of Dentistry. METHODS: To this end, 24 journals included in Journal Citation Reports, 6 pertaining to each quartile were selected by a stratified sampling and then an ordinal regression model was estimated stepwise considering the journal impact factor quartile as response variable. RESULTS: The estimation procedure concluded that the average number of papers published yearly by a journal and the percentage of systematic reviews are the most significant variables to be considered, along with the factor representing the journal's degree of adherence to recommendations by the International Committee of Medical Journal Editors. CONCLUSIONS/CLINICAL SIGNIFICANCE: Systematic reviews have significant effect on the Journal Impact Factor position of a journal as well as adherence to ICMJE recommendations, while papers publishing clinical trials bear no influence on this factor. Greater yearly average of published papers in a journal means a higher impact factor.

A principal component regression model to forecast airborne concentration of Cupressaceae pollen in the city of Granada (SE Spain), during 1995-2006.

The problem of developing a 2-week-on ahead forecast of atmospheric cypress pollen levels is tackled in this paper by developing a principal component multiple regression model involving several climatic variables. The efficacy of the proposed model is validated by means of an application to real data of Cupressaceae pollen concentration in the city of Granada (southeast of Spain). The model was applied to data from 11 consecutive years (1995-2005), with 2006 being used to validate the forecasts. Based on the work of different authors, factors as temperature, humidity, hours of sun and wind speed were incorporated in the model. This methodology explains approximately 75-80% of the variability in the airborne Cupressaceae pollen concentration.

Forecasting pollen concentration by a two-step functional model.

A functional regression model to forecast the cypress pollen concentration during a given time interval, considering the air temperature in a previous interval as the input, is derived by means of a two-step procedure. This estimation is carried out by functional principal component (FPC) analysis and the residual noise is also modeled by FPC regression, taking as the explicative process the pollen concentration during the earlier interval. The prediction performance is then tested on pollen data series recorded in Granada (Spain) over a period of 10 years.

Effect of chlorhexidine-thymol varnish on root caries in a geriatric population: a randomized double-blind clinical trial.

OBJECTIVES: Little is known about the effect of Cervitec, a chlorhexidine-thymol varnish, on root caries. Our objective was to determine whether a 3-monthly application of Cervitec over 1 year would limit the progress of existing root caries lesions and reduce the incidence of dental root caries in a group of dentate institutionalized elderly, as a complement to their usual oral hygiene practices. METHODS: A double-blind randomized clinical trial was conducted in 68 subjects (34 per group) in two residences in Almería (Spain). Twenty-one subjects with 60 root caries lesions and 25 with 65 lesions, in the Cervitec and placebo groups, respectively, completed the study. Varnishes were applied twice in the first week, 1 month later, and every 3 months until the end of the study. Clinical parameters associated with established lesions were determined at baseline and after 6 and 12 months, as was the incidence of root caries lesions. RESULTS: The clinical evolution of lesions was significantly better in the Cervitec group as opposed to the placebo group in terms of width, height, color, and texture. The increase in root caries was significantly lower (p=0.039) in the Cervitec group. CONCLUSION: According to these results, Cervitec may help to control established root lesions and reduce the incidence of root caries lesion among institutionalized elderly.

Efficacy of chlorhexidine-thymol varnish (Cervitec) against plaque accumulation and gingival inflammation in a geriatric population.

OBJECTIVES: To determine whether the 3-monthly application of chlorhexidine (CHX)-thymol varnish is an effective method of controlling plaque and gingivitis in a group of institutionalised elderly as a complement to their usual oral hygiene practices. DESIGN: A 6-month double-blind clinical trial. SETTING: Two residential homes in Almería (Spain). PARTICIPANTS: Fifty-six dentate subjects aged above 64 years who completed the 6-month study. INTERVENTION: The study subjects were randomly assigned to one of two groups (Cervitec or placebo). Varnishes were applied twice in the first week of the study and were applied again a month later and every 3 months until the end of the study. The patients continued with their usual oral hygiene practices throughout the study. MEASUREMENT: Plaque index and gingival index scores were determined at baseline and after 1, 3 and 6 months. RESULTS: Treatment with Cervitec varnish had a statistically significant effect overtime on the gingival index score (p = 0.029), but not on the plaque index score (p = 0.651). The groups did not significantly differ in reductions in plaque or gingival index scores between baseline and 1, 3 or 6 months. CONCLUSION: According to these results, Cervitec, a CHX-thymol varnish, does not appear to reduce plaque and gingivitis by a 3-monthly application in the institutionalised elderly with poor oral hygiene. Wider studies are required to investigate different varnishing protocols in geriatric populations.