Paul Tramini

Association between Caries Experience and Body Mass Index in 12-Year-Old French Children

The prevalence of overweight and obesity reached 19.7% in 12-year-old French children in the year 2005. Recently, nationwide programs have been broadly implemented in France to reduce the overconsumption of sugars, salt and fat. The aims of this study were to assess the distribution of body mass index (BMI) and D3+4MFT index in a sample of 12-year-old French children, and to compare several regression models in order to analyze the association between these two indices. A cross-sectional study was conducted in Montpellier, France, and the height, weight, D3+4MFT, sugar and soft drink consumption were recorded in a randomly selected sample of 835 schoolchildren. In order to analyze the association between BMI and DMFT, four models of regression were tested: logistic, Poisson, zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB). The mean BMI was 18.9 for the whole sample and the corresponding DMFT value was 1.47. The caries prevalence was 51.7%. The best fitted models for testing the association between BMI and DMFT were ZIP and ZINB models. They showed a significant association between DMFT and sugar consumption, but not with BMI. As a result of the best fitted models (ZIP and ZINB), where BMI was not statistically associated with DMFT, we conclude, within the limits of a cross-sectional survey, that there is no association between these two variables.

A Raman Spectroscopic Investigation of Dentin and Enamel Structures Modified by Lactic Acid

Confocal Raman microspectrometry allows a thorough molecular analysis of mineralised dental tissues. The output information is provided in the form of curves representing the intensity of the signal according to the frequency, and its mathematical exploitation permits all sorts of comparative and quantitative analyses. By this process, we investigated the in vitro action of lactic acid on enamel and dentin from human permanent teeth. Modifications due to the acidic attack essentially concern phosphate grouping PO43–, which represents the mineral phase in enamel and dentin (hydroxyapatite): on Raman spectra, changes in intensity of the PO43– band are linked to the type of dentin, to its anatomical location, and to the age of the subject. The variability of the dentinal chemical structure was confirmed by a quantitative statistical analysis, revealing a significant spectral difference between coronal and root dentin.

A method of age estimation using Raman microspectrometry imaging of the human dentin

The aim of this work is to establish a correlation between ageing and Raman spectra imaging of human teeth. Raman spectrum of an analysed sample is characteristic of its chemical components. By exploring the different dentinal areas on each tooth, we sought to find a correlation between noticeable variability on Raman spectra and the stages of dentinal evolution with advancing age. A study on 30 teeth analysed by Raman microspectrometry was used to select predictors of age, and it allowed us to determine a regression formula, with age as a dependent variable. Our data were computed by means of a statistical method called partial least squares (PLS) regression. This method was specially adapted for this kind of situation, where we have numerous predictors and relatively few observations. The regression formula was performed on a test sample of four more teeth, and we obtained a correct age estimation, with a mean error of more or less than 5 years. The main benefits of this method was a minimal and non-destructive tooth preparation, which led to an efficient age prediction, for any age group.

Association of caries experience in 12-year-old children in Heidelberg, Germany, and Montpellier, France, with different caries preventive measures.

UNLABELLED In Germany and France, different approaches to oral health promotion have been chosen. OBJECTIVES It was the aim of the present study to assess whether different preventive measures were positively or negatively associated with caries experience in 12-year-old children in Heidelberg, Germany, and in Montpellier, France. METHODS In the school year 1998/99, 12-year-old children were examined in Heidelberg (n=864) and in Montpellier (n =828). D3+4MFT, D3+4MFS (D3+4=dentinal caries), prevalence of fissure sealants and use of fluorides were recorded. RESULTS The mean D3+4MFT scores of the pupils in Heidelberg and Montpellier were 1.56 and 1.42, the proportion of caries-free children being 43.5% and 46.9%, respectively. In 63.2% of the children in Heidelberg and in 6.8% of the children in Montpellier, at least one fissure sealed tooth was found. Fluoridated salt was used by 38.8% of families of the 12-year-olds from Heidelberg and the corresponding value was 73.3% in Montpellier. Topical fluorides were applied by 39.9% of the children in Heidelberg, but only by 5.4% of pupils in Montpellier. Multiple regression analysis revealed that, in Heidelberg, fissure sealants and the combination of topical fluorides and fluoridated salt were negatively associated with the D3+4MFT values, while in Montpellier the frequency of dental visits was positively associated with the D3+4MFT scores. CONCLUSION A further decrease in the caries experience of 12-year-old children may well be obtainable by enlarging the share of marketed fluoridated salt in Heidelberg, by increasing the application of fissure sealants in Montpellier, and by extending the use of topical fluorides in both cities.

Coronal and apical lesions, environmental factors: study in a modern and an archeological population.

Apical periodontitis (AP) are frequent findings in contemporary dental practice in association with dental pathology or dental care. They have also been studied from an anthropological background. The purpose of this study was to compare the prevalence of apical and dental lesions in an archeological Middle Ages sample and a modern population, and to evaluate the influence of environmental factors. Both the archaeological sample group and dental practice subjects were from southern France. The study included full mouth surveys of 252 individuals (2,780 teeth) from a historic necropolis and 223 subjects (5,678 teeth) randomly selected from the Gard area. Tooth wear, caries, and AP were accounted for clinically and radiographically according to specific indexes. Significant differences were found between period and age in the archeological sample as regards the main risk factors for AP. Antemortem teeth loss and dental wear had been reduced, whereas caries rates and AP had increased between archaeological and modern population. The AP ratio was associated with the level of dental care in the modern population. Although significant variations could be observed between archaeological periods, the rupture in E3 (sixteenth and seventeenth centuries) leads to consider the associated population as a premodern. However, it was found that although cultural and alimentary factors seemed to be the main risk factors in an archeological population, dental care seemed to have a strong influence on AP ratio in modern ones.

Effects of L-arginine and phosphodiesterase-5 inhibitor, sildenafil, on inflammation and airway responsiveness of sensitized BP2 mice.

Nitric oxide (NO) levels are elevated in the exhaled breath of asthmatic patients and NO is considered as a biomarker of airway inflammation. However, the functions of NO in the airways are not completely understood. l‐arginine, as the substrate of NO synthases, is the precursor of NO which stimulates guanylate cyclase and leads to the formation of cyclic GMP (cGMP). Sildenafil, a phosphodiestérase‐5 (PDE‐5) inhibitor, prevents the degradation of cGMP. In this study the effects of l‐arginine and sildenafil treatment, alone or in combination, were evaluated in ovalbumin‐sensitized BP2 mice. These effects concerning the airway responsiveness to inhaled methacholine (MCh) were evaluated by whole‐body plethysmography (WBP), the inflammatory response evaluated by bronchoalveolar lavage fluid (BALF) analyses and lung tissue biopsies (eosinophilic inflammation associated with lung remodelling), and NO metabolite measurements (by Griess reaction) in BALF. Ovalbumin sensitization induced: (a) an inflammatory reaction with eosinophil and neutrophil influx in BALF and lung; and (b) an increased bronchial responsiveness to MCh. l‐arginine treatment [50 mg/kg intraperitoneally (i.p.), for 7 days] increased the relative amount of eosinophils and neutrophils in BALF, had a tendency to increase the airway responsiveness to inhaled MCh and increased the NO metabolite level in BAL. Sildenafil treatment (20 mg/kg i.p. for 7 days) did not affect the airway responsiveness to MCh and had a lower effect compared with l‐arginine on inflammatory reactions. The combination of the two treatments resulted in a dramatic enhancement of the airway responsiveness to inhaled MCh. The relative amount of eosinophils was increased and lung histology showed obvious worsened tissular lesions such as epithelial shedding and hypertrophy, hyperplasia of smooth muscle cells, and fibrosis. These findings are consistent with the notion that NO production plays a role in the development of airway inflammation and hyperresponsiveness of sensitized mice and highlighted the potential risk of the l‐arginine dietary complement or PDE5 treatment in asthmatic patients.

Prevalence of palatine tonsilloliths: a retrospective study on 150 consecutive CT examinations

OBJECTIVES To evaluate the prevalence of palatine tonsilloliths. METHODS 150 consecutive CT examinations (75 males and 75 females) were read. RESULTS Tonsilloliths were found in 37 patients (24.6%; confidence interval 17.7-31.6%), of which 18 (48%) had a bilateral location. No influence of sex or age was observed (p = 0.37 and p = 0.57, respectively). 26 patients (70%) had more than 1 concretion. The largest tonsillolith was 7 mm. None of the tonsilloliths found were involved in the reason for prescribing the CT. The radiographic density of the tonsilloliths was between 216 and 2959 HU. CONCLUSIONS Palatine tonsilloliths could affect approximately one-quarter of the population. This prevalence is likely to be underestimated in daily clinical practice because small concretions do not result in any functional impairment and are not visible on orthopantomographs.

Relationship between caries prevalence and fissure sealants among 12-year-old German children at three educational strata

SummaryObjectives:To investigate the relationship between caries prevalence and fissure sealants among 12-year-old German children at three educational levels. Methods:In 1998 a cross-sectional investigation which comprised 60 % of the 12-year-old children was performed in Heidelberg, Germany. The children attended three types of schools: Gymnasium, Hauptschule, and Realschule. The children received a dental examination. Teeth with caries experience were recorded according to WHO criteria, and teeth with a fissure sealant were also noted. Results:The mean number of fissure sealed teeth per child was 2.49 (Gymnasium), 2.31 (Realschule) and 1.17 (Hauptschule). In children who attended a Gymnasium the mean DMFT scores were the lowest (0.87 in children with fissure sealant and 1.31 in children without fissure sealant). The corresponding values for children who attended a Realschule were distinctly higher. The highest mean DMFT scores (2.14 and 3.48, resp.) were observed in children who attended a Hauptschule. The proportion of caries-free children was higher in all three types of school when fissure sealants were present. Conclusions:In spite of a high prevalence of fissure sealants there is an unequal caries experience among 12-year-old children from different educational strata. To improve this situation, persons important to promotion of dental health should do all their part to ensure that fissure sealants are applied to permanent teeth as early as possible, especially when children have caries experience in their primary dentition.

Molecular structural analysis of carious lesions using micro‐Raman spectroscopy

In clinical situations carious dentine tissues can be discriminated by most caries fluorescence detection tools, including a new fluorescence intra-oral camera. The objectives of this study were: (i) to analyze the Raman spectra of sound, carious, and demineralized dentine, (ii) to compare this spectral analysis with the fluorescence variation observed when using a fluorescence camera, and (iii) to evaluate the involvement of the Maillard reaction in the fluorescence variations. The first positive hypothesis tested was that the fluorescence of carious dentine obtained using a fluorescence camera and the Raman spectra variation were closely related. The second was that the variation of fluorescence could be linked with the Maillard reaction. Sound dentine, sound dentine demineralized in aqueous nitric acid solution, carious soft dentine, sound dentine demineralized in lactic acid solution, sound dentine demineralized in aqueous nitric acid solution and immersed in methylglycoxal solution, and sound dentine demineralized in aqueous nitric acid solution and immersed in methylglycoxal and glucose solutions, were studied using micro-Raman spectroscopy. Modifications in the band ratio of amide, phosphate, and carbonate were observed in the decayed and demineralized groups compared with the sound dentine group. The results indicate that a close relationship exists between the Maillard reaction and fluorescence variation.

Development of a new quantitative gas permeability method for dental implant-abutment connection tightness assessment

BackgroundMost dental implant systems are presently made of two pieces: the implant itself and the abutment. The connection tightness between those two pieces is a key point to prevent bacterial proliferation, tissue inflammation and bone loss. The leak has been previously estimated by microbial, color tracer and endotoxin percolation.MethodsA new nitrogen flow technique was developed for implant-abutment connection leakage measurement, adapted from a recent, sensitive, reproducible and quantitative method used to assess endodontic sealing.ResultsThe results show very significant differences between various sealing and screwing conditions. The remaining flow was lower after key screwing compared to hand screwing (p = 0.03) and remained different from the negative test (p = 0.0004). The method reproducibility was very good, with a coefficient of variation of 1.29%.ConclusionsTherefore, the presented new gas flow method appears to be a simple and robust method to compare different implant systems. It allows successive measures without disconnecting the abutment from the implant and should in particular be used to assess the behavior of the connection before and after mechanical stress.