Cephalometric evaluation of pharyngeal obstructive factors in patients with sleep apneas syndrome.

To determine accurately the morphological characteristics specific to patients with sleep apneas syndrome (SAS), a group of 43 adult males with SAS was compared in a cephalometric evaluation with a homologous control group. In SAS patients, the soft palate was elongated; the sagittal dimensions of upper face and anterior cranial base were reduced and correlated with reduced bony pharynx opening; and the increased lower face height was associated with a retruded position of the chin and tongue, thus contributing to lower pharynx crowding. With the four variables entering the discriminant function analysis, 93 percent of the whole population was correctly classified. If anatomical rehabilitation of the pharynx is to be envisaged, the leading factors to consider should be: soft palate length, maxillary position, chin and tongue position, in that order.

Comparison of lead levels in human permanent teeth from Strasbourg, Mexico City, and rural zones of Alsace.

A comparative study of the mean lead concentrations in enamel and dentin of human premolars and permanent molars was conducted by means of a systematic sampling procedure with energy-dispersive x-ray fluorescence analysis. In a first series of analyses, no significant statistical differences in mean lead concentrations at various levels of enamel and dentin were noted between young patients of Strasbourg and those of small villages of Alsace, nor between elderly patients living in these two locations, despite the fact that motor traffic was significantly lower in the rural zones. However, in both locations, a significantly higher concentration of lead was observed in enamel and dentin in relation to age. In a second series of analyses, the mean lead concentrations of both dental hard tissues of premolars and permanent molars of young individuals from Strasbourg, rural Alsace, and Mexico City were compared. Significantly higher mean lead concentrations were found in enamel and dentin samples from Mexico City. This was most evident for inner coronal dentin (5.7 and 6.1 times greater than in teeth of Strasbourg and rural zones of Alsace, respectively) and for pulpal root dentin (6.9 and 8.9 times greater than in teeth of Strasbourg and rural zones of Alsace). It is proposed that the higher lead concentrations are related to the higher lead content of motor gasoline and to more intense traffic conditions. The dental hard tissues appear to be of value for the study of environmental lead pollution.

Periodontal treatment needs in populations of high- and low-fluoride areas of Morocco.

The purpose of this study was to determine the periodontal status and treatment needs, using the CPITN index, in a population aged 7 to 60 years residing in the fluorosis area of Khouribga and the non-fluorosis area of Beni-Mellal, Morocco. A total of 2378 subjects was studied. In the youngest age groups, more subjects and sextants from Khouribga than from Beni-Mellal were free of periodontal diseases. Conversely, in Beni-Mellal, subjects in the youngest age groups presented a higher mean number of sextants with calculus than those from Khouribga. In combining the 2 areas, 1.3% of the 2319 dentate subjects examined needed no treatment and 98.7% needed at least oral hygiene instructions (TN1). The present study, based on the CPITN index, demonstrated in both areas a high prevalence of gingivitis, and a relatively low prevalence of deep pocketing, occurring on the average in less than half a sextant in the total populations.

Dental caries and fluorosis in children from high and low fluoride areas of Morocco.

The purpose of this study was to estimate the prevalence and the severity of dental caries and dental fluorosis in primary and permanent teeth of 582 subjects, aged 7 to 16 years, from the fluorosis area of Khouribga and the non-fluorosis area of Beni Mellal, Morocco. At age-group 7-10, where 67.8 percent of primary teeth were present, about 35 percent of the children were affected in the high-fluoride area and the community fluorosis index was 0.86. The percentage and average number of erupted permanent teeth were higher in Beni Mellal than in Khouribga for 11-12 and 13-14-year-old age-groups. Significant differences in caries prevalence were observed between the high- and low-fluoride areas. In both regions, high and low prevalence of dental caries was observed in the primary and permanent teeth, respectively.

The effects of airborne fluorides on oral conditions in Morocco.

The purpose of this study was to determine the prevalence and severity of dental caries and dental fluorosis, as well as various other oral conditions, in 2378 subjects (ages seven to 60) living in the fluoridated area of Khouribga and the non-fluoridated area of Beni Mellal, Morocco. The community index of dental fluorosis (CFI) ranged from 1.99 to 2.80 in the high-fluoride area: Over 90% of the population was affected, and more than one-third of the subjects showed moderate dental fluorosis. However, in Beni Mellal, more than 96% of the dentate subjects examined were free of dental fluorosis, and the CFI of 0.02 was considered not significant. Significant differences were observed between the two areas with respect to caries prevalence. DMFT and DMFS indices were markedly lower in the fluorosis area of Khouribga. The oral conditions of subjects appeared to be better in Khouribga, where the gingival and calculus indices were significantly lower than in Beni Mellal. The analyses of covariance showed no significant differences in plaque accumulation (PI) between the Khouribga and Beni Mellal samples. However, a close statistical correlation was found between PI and GI in Beni Mellal and Khouribga.

[Sampling procedures of a national survey on the orodental status of 6-15-year-old children in France]. / Plan de sondage de l'enquête nationale sur l'état buccodentaire des enfants âgés de 6 à 15 ans en France.

The multistage sampling procedure for the study of dental caries prevalence of 6 to 15 year old children of France consisted of 2 stratification variables and several levels of sampling. The geographical stratification controlled the distribution of the selected sample for the whole French territory. The second stratification variable consisted of the differentiation of urban and rural zones. The sampling rate was 1/400 and each schoolchild had the same probability of being selected. This rate gave samples of about 2,000 children for each age group, giving an adequate precision for the DMFT, DMFS and dft indices. This multistage sampling procedure was unbiased.

[The orodental status of the French population 6-15 years of age]. / Etat bucco-dentaire de la population française âgée de 6 à 15 ans.

A representative sample of 19,366 schoolchildren of France, aged 6 to 15 years, was randomly selected. Examiner teams from each of the 16 Faculties of Dental Surgery of France were trained together to be well calibrated. The dental caries prevalence was determined in each age group using the dft, dfs, DMFT and DMFS indices. The periodontal conditions were measured using the plaque index (Silness and Löe, 1964), the calculus index (Marthaler, 1966) and the gingival index (Löe and Silness, 1963). The mean DMFT index increased from 0.5 at age 6 to 6.9 at age 15 years. This index increased by 0.5 from one age group to the next until age 10, and from 1.0 from age 11 to age 15. The DMFS index increased from 0.8 to 13.0 between 6 and 15 years of age. In each age group, the numbers of carious and untreated surfaces were very similar to the number of filled surfaces. The percentage of children with caries-free permanent teeth decreased from 78.5% to 8.2% between 6 and 15 years of age. A direct relation was observed between the caries indices and the socio-economic category of the parents. The senior management and private professions presented the lowest indices.

Zinc and strontium analyses by energy dispersive X-ray fluorescence in human permanent teeth.

The zinc and strontium content of enamel and dentine from humans aged 9-64 yr was analysed, after systematic sampling, by X-ray fluorescence. Relatively high levels of zinc were found in both hard tissues but there was no significant increase with age. Zinc content decreased significantly from outer to inner enamel and increased significantly again from peripheral to pulpal coronal and root dentine. The strontium content was significantly higher in enamel than in dentine; there was a significant increase with age in enamel but not in dentine. However, outer and inner enamel showed no significant difference in strontium content. Almost similar amounts of strontium were found in coronal and root dentine.

[Vertical typology and natural posture of the head]. / Typologie verticale et posture naturelle de la tête.

The relationship between head posture and vertical typology were evaluated in a sample of 98 young adults. Sub groups of opposite typology were also compared. A strong correlation existed between head posture and facial divergence when evaluated with the variable SN/PM and face post./face ant. Head posture is in extension when facial divergence is important. No correlation existed between posture and % face inf. Face post./face ant. was the best variable in evaluating the relationship between vertical typology and head posture.

National survey of caries prevalence in 6-15-year-old children in France.

The prevalence of dental caries in France is not known on a nationwide basis, despite the fact that a number of epidemiological studies have been conducted in various parts of the country. The aim of the present study was to provide a national baseline examination of the dental health of children in 1987 since, beginning in November, 1986, the sale of fluoridated salt began in France. A multi-stage probability sample of 19,366 children was selected as representative of the 6-to-15-year-old population. The sample covered all the 95 departments of France. Teams of well-calibrated examiners were constituted in each of the sixteen Faculties of Dental Surgery of France. The prevalence of caries for each age group was determined by means of DMFT, DMFS, dft, and dfs indices. Periodontal conditions were assessed by means of the Plaque Index (Silness and Löe, 1964), the Calculus Index (Marthaler, 1966), and the Gingival Index (Löe and Silness, 1963). Calculation of the mean DMFT index showed, respectively, 0.5 and 1.0 new carious teeth per year under and over the age of 11. The mean values of the DMFT index at ages 6, 12, and 15 were, respectively, 0.5, 4.2, and 6.9. Under the age of 11, the mean DMFS index increased by one between each successive age group and by nearly two over the age of 11. The mean values of the DMFS index at ages 6, 12, and 15 were, respectively, 0.8, 7.6, and 13.0. The percentage of caries-free children decreased from 32.2% at age 6 to 7.9% at age 15.

[Epidemiological study of the oro-dental status of the children of the Alsace and the Franche-Comté]. / Etude épidémiologique de l'état bucco-dentaire des enfants d'Alsace et de Franche-Comté.

Within a national epidemiological study conducted in France by the 16 Faculties of Dentistry, 946 school-children aged 6 to 15 years were randomly selected and examined in East of France. The Dental Faculty of Strasbourg studied the following departments: Doubs, Jura, Bas-Rhin, Haut-Rhin and Territoire de Belfort. Twenty per cent of the 12 year old children had a DMFT of 0, whereas by the age of 15 this percentage felt to 7%. The mean DMFT and DMFS of the 12 year old children were respectively of 4.6 and 8.7. The mean plaque index varied from 1.2 to 1.5 for all age groups. The mean calculus index increased progressively with age from 0.1 to 0.6. The mean gingival index was almost constant until the age of 8 (0.6 to 0.8). It reached 1.2 at 9 and remained unchanged until 15.

A method of lead determination in human teeth by energy dispersive X-ray fluorescence (EDXRF).

A systematic sampling procedure was combined with a method of energy dispersive X-ray fluorescence (EDXRF) to study lead content and its variations in human teeth. On serial ground sections made on unembedded permanent teeth of inhabitants of Strasbourg with a special diamond rotating disk, 2 series of 500 microns large punch biopsies were made systematically in 5 directions from the tooth surface to the inner pulpal dentine with a micro-punching unit. In addition, pooled fragments of enamel and dentine were made for each tooth. On each punched fragment or pooled sample, lead content was determined after dissolution in ultrapure nitric acid, on a 4 microns thick polypropylene film, and irradiation with a Siemens EDXRF prototype with direct sample excitation by a high power X-ray tube with a molybdenum anode. Fluorescence was detected by a Si(Li) detector and calcium was used as an internal standard. This technique allowed a rapid, automatic, multielementary and non-destructive analysis of microsamples with good detection limits.

Craniofacial characteristics in patients with obstructive sleep apneas syndrome.

Obstructive sleep apneas syndrome (OSAS) has been associated with a clinical reduction of the pharyngeal spaces. To define whether predisposing skeletal craniofacial conditions exist in OSAS patients, 32 OSAS adult patients were compared in a cephalometric investigation with a control sample of 40 adults with ideal dentofacial traits. A t-test assessed the statistical significance of the differences in the two groups; correlation matrix tabulation and discriminant function analysis helped in the identification of the influence of different variables in segregation of the two populations. The following observations were made: There were no differences in maxillary or mandibular prognathism between the two groups. The sagittal dimension of the cranial base was significantly reduced in the OSAS sample, as was the bony pharyngeal opening and maxillary length. This posterior facial compression was associated with increased lower face height (p less than 0.01 in all cases). There were significant correlations in both groups between cranial base length or angulation and pharyngeal opening (p less than 0.01). Eighty percent of the population was correctly sorted out using the discriminant function analysis, with only eight controls and five OSAS patients misclassified. However, this analysis suggested that factors other than the cephalometric may be involved in OSAS.

Age-related lead increase in human permanent teeth demonstrated by energy dispersive X-ray fluorescence.

The combined use of a systematic sampling procedure with energy dispersive X-ray fluorescence on non-erupted and erupted permanent premolars and molars in patients aged 9 to 64 years, who have lived all their lives in Strasbourg, showed a higher total lead content in dentine compared to enamel, with an approximate ratio of 2:1. In addition, a lead increase was observed in both tissues with age. The lead increase in dentine was more significant and the highest lead values were noted in the inner pulpal dentine layer of the oldest age group. When compared to similar lead studies made on permanent teeth in urban areas, it can be concluded that the lead content in the teeth of the inhabitants of Strasbourg can be considered as low.

Identification of Flavobacterium strains by gas liquid chromatographic analysis of volatile fatty acids produced in culture.

The classification previously established for 74 Flavobacterium strains by gas liquid chromatographic (GLC) analysis of volatile fatty acids (VFA) produced in culture allowed the recovery of 9 groups (J. gen. Microbiol., 1986, 132, 2723-2732). Since graphic representation of the strains based on the first 3 factors obtained by principal component analysis (PCA) clearly separated these groups, we tried to identify 80 new strains by comparing their positions with those of the 9 groups, on the basis of both hierarchical classification and PCA methods. Of the 153 strains studied, only 12 were not allocated to a group corresponding to their original biochemical identification. Thus, on the whole, this characterization method by GLC analysis seemed satisfactory, although it could not be established whether the method was adequate for routine identification, or would serve merely as a complement.

Approximal caries diagnosis in epidemiological studies: transillumination or bitewing radiographs?

The aim of this study was to compare the results obtained by transillumination and bitewing radiography in the diagnosis of caries affecting approximal surfaces of molar and premolar teeth for epidemiological surveys. 3960 posterior approximal surfaces on the right side of 330 patients aged 5 to 35 years were examined using a transillumination probe with a 1.5 mm diameters light source (Oralum, Rocky Mountain, Denver, Colorado) and bitewing radiographs using a portable dental apparatus (Elin, Wien, 60kV, 15mA. Transillumination detected 89% of the carious lesions reaching dentine diagnosed on radiographs and no statistically significant differences were observed in the diagnosis yield of the two systems. However, transillumination detected only 45% of these lesions diagnosed from bitewings as being confined to the enamel. Transillumination also made it possible to detect approximal caries into dentine in teeth covered by orthodontic bands. Thus comparative study gives experimental support to the use of transillumination in large epidemiological studies. The transillumination method is however not suitable for epidemiological trials including caries confined to the enamel.