Occlusal features of 5-year-old Greek children: a cross-sectional national study.

BACKGROUND: Occlusal characteristics of the primary dentition are crucial in predicting and determining permanent tooth alignment and occlusion. The aim of our study was to determine the occlusal characteristics of the primary dentition of 5-year-old children in Greece through a national pathfinder survey. METHODS: A stratified cluster sample of 1222 5-year-old children was selected according to the WHO guidelines for national pathfinder surveys. Five occlusal traits were registered clinically in centric occlusion, separately for the left and right sides: sagittal relationships of the second primary molars and primary canines, overjet, overbite, crossbite, and maxillary and mandibular spacing. RESULTS: Most children showed a flush terminal plane of primary second molars (44.8%), a class I primary canine relationship (52.2%) and normal overjet (46.4%), but a high prevalence of Class II canine relationship (25.6%) and overjet (37.8%) were also observed. A normal overbite was found in 40% of the children and 40% had a deep overbite. Spacing was apparent in both maxilla (71.1% of children) and mandible (56.4%). The prevalence of open bite and distal step molar relationship significantly rose in children with non-nutritive sucking habits. CONCLUSIONS: Νon-nutritive habits were associated to altered occlusal features. No sex significant differences were found in either the sagittal relationships of second primary molars and primary canines, or overjet, overbite, crossbite and spacing.

Orthodontic Status and Orthodontic Treatment Need of 12- and 15-Year-Old Greek Adolescents: A National Pathfinder Survey.

The purpose of this research was to assess the orthodontic status and orthodontic treatment needs of 12- and 15-year-old schoolchildren in Greece, in relation to sociodemographic factors and parental education level. A total of 1102 12-year-old children and 1131 15-year-old adolescents across Greece were assessed using the Modified Dental Health component (DHC) of the Index of Orthodontic Treatment Need (IOTN). An amount of 38.7% of 12-year-olds and 33.7% of 15-year-olds were in definite need of orthodontic treatment. The most common etiologic factors were tooth eruption and position anomalies. A higher rate of orthodontic treatment need was recorded among subjects with lower parental education level. Class I malocclusion was found in 50.9%, Class II in 38.4% and Class III in 10.8% of the total sample. A higher incidence of dental trauma was found in the 12-year-olds presenting with a Class II molar relationship and >3 mm overjet. The need for orthodontic treatment in Greece was higher, in comparison to other European countries, with one out of two children presenting a severe overjet associated with a high incidence of dental trauma. One out of three adolescents were still judged as having a need for orthodontic treatment by the age of 15.

Caries prevalence and caries experience (ICDAS II criteria) of 5-, 12- and 15-year-old Greek children in relation to socio-demographic risk indicators. Trends at the national level in a period of a decade.

PURPOSE: To study the caries status of 5, 12 and 15-year-old Greek children, assess how disease parameters are related to socio-demographic indicators and identify relevant trends at the national level. METHODS: A stratified cluster sample of 3702 children in total was randomly selected and examined clinically for caries (ICDAS II criteria). Caries experience was outlined by adapting ICDAS0-6 criteria to the d/D component of the WHO dmf/DMF index configuration. Percentages (%) of caries experience-free children, of children with initial caries (ICDAS1-2), and the mean d1-2t/D1-2T, d3-6mft/D3-6MFT and d3-6mfs/D3-6MFS indices were calculated. The probability of presenting with d1-2t/D1-2T ≥ 1 was assessed by binary logistic regression analysis, whereas negative binomial regression models examined the effect of socio-demographic parameters on d3-6mfs/D3-6MFS indices (level of significance: p ≤ 0.05). RESULTS: 60.1%, 48.1%, and 34.7% of the 5, 12, and 15-year-old children, respectively, had no caries experience at the defect level (d3-6mft/D3-6MFT = 0). Initial lesions (ICDAS1-2) were detected in 17.7%, 19.3% and 17.4% of the 5, 12 and 15-year-olds, accordingly. Mean d1-2t/D1-2T was 0.93, 1.70, and 2.51, whereas mean d3-6mft/D3-6MFT was 1.48, 1.61, and 2.46 for the 5, 12, and 15-year-olds, respectively. Children with higher educated parents and 15-year-old urban residents exhibited significantly less caries experience at the defect level. Initial caries lesions presented a significantly higher probability of being detected in urban-residing 5- and 15-year-olds, while no consistent trend could be identified for parental education level. Caries prevalence and experience levels declined for all age groups in ten years. CONCLUSION: Although the dental health of Greek children has improved disparities remain, calling for organised primary and secondary preventive interventions.

Dental Caries Prevalence and Experience (ICDAS II Criteria) of 5-, 12- and 15-Year-Old Children and Adolescents with an Immigrant Background in Greece, Compared with the Host Population: A Cross-Sectional Study.

Evidence regarding disparities in oral health among native and immigrant child and adolescent populations in Europe is scarce. The present study aimed to determine the caries status of 5-, 12-, and 15-year-olds with an immigrant background in Greece in relation to their sociodemographic characteristics and compare their caries levels with those of their native Greek peers. A sample of 707 immigrants underwent clinical examination for caries (ICDAS II criteria), followed by a calculation of caries prevalence and experience estimates (2013-2014). Multivariable regression models assessed the effect of ethnic background on the caries experience (d3-6mfs/D3-6MFS) of the total (707 immigrants and 3702 Greeks) population, and the association between parental education level and the immigrants' d3-6mfs/D3-6MFS. Among the 5- and 12-year-olds, those with an immigrant background demonstrated higher caries rates and had unfulfilled treatment needs at higher proportions. Among 15-year-old adolescents, no considerable differences in caries status were observed according to ethnic background (native Greek or immigrant). The strength of the association between immigrant background and caries experience levels attenuated gradually with increasing age (IRR = 1.61, 1.27 and 1.10, and p = 0.001, p = 0.006 and p = 0.331 for 5-, 12- and 15-year-olds, respectively). Among the immigrants, adolescents with less educated mothers exhibited elevated caries levels. Public health strategies should prioritize immigrant children and early adolescents in order to reduce the existing ethnic disparities in oral health.

A computer-aided automated methodology for the detection and classification of occlusal caries from photographic color images.

The aim of this work is to present a computer-aided automated methodology for the assessment of carious lesions, according to the International Caries Detection and Assessment System (ICDAS II), which are located on the occlusal surfaces of posterior permanent teeth from photographic color tooth images. The proposed methodology consists of two stages: (a) the detection of regions of interest and (b) the classification of the detected regions according to ICDAS ΙΙ. In the first stage, pre-processing, segmentation and post-processing mechanisms were employed. For each pixel of the detected regions, a 15×15 neighborhood is used and a set of intensity-based and texture-based features were extracted. A correlation based technique was applied to select a subset of 36 features which were given as input into the classification stage, where five classifiers (J48, Random Tree, Random Forests, Support Vector Machines and Naïve Bayes) were compared to conclude to the best one, in our case, to Random Forests. The methodology was evaluated on a set of 103 digital color images where 425 regions of interest from occlusal surfaces of extracted permanent teeth were manually segmented and classified, based on visual assessments by two experts. The methodology correctly detected 337 out of 340 regions in the detection stage with accuracy of detection 80%. For the classification stage an overall accuracy 83% is achieved. The proposed methodology provides an objective and fully automated caries diagnostic system for occlusal carious lesions with similar or better performance of a trained dentist taking into consideration the available medical knowledge.

Occlusal caries detection using random walker algorithm: a graph approach.

The aim of this work is to present a modification of the Random Walker algorithm for the segmentation of occlusal caries from photographic color images. The modification improves the detection and time execution performance of the classical Random Walker algorithm and also deals with the limitations and difficulties that the specific type of images impose to the algorithm. The proposed modification consists of eight steps: 1) definition of the seed points, 2) conversion of the image to gray scale, 3) application of watershed transformation, 4) computation of the centroid of each region, 5) construction of the graph, 6) application of the Random Walker algorithm, 7) smoothing and extraction of the perimeter of the regions of interest and 8) overlay of the results. The algorithm was evaluated using a set of 96 images where 339 areas of interest were manually segmented by an expert. The obtained segmentation accuracy is 93%.

Prevalence of sealants in relation to dental caries on the permanent molars of 12 and 15-year-old Greek adolescents. A national pathfinder survey.

BACKGROUND: The use of sealants as an effective measure for the prevention of pit and fissure caries in children has been well documented by several studies; either they are used on an individual or on a public health basis. In order to plan and establish a national preventive program with sealants in a community, it is mandatory to know the epidemiological pattern of caries along with other variables influencing their use and effectiveness. AIMS: To assess the utilization and distribution pattern of pit and fissure sealants on the first and second permanent molars of Greek adolescents and to evaluate whether the existing usage of sealants and some socio-demographic factors are correlated to caries prevalence on the population examined METHODS: A stratified cluster sample of 2481 Greek adolescents was selected according to WHO guidelines (1224 twelve and 1,257 fifteen-year-old), living in urban and rural areas in 11 districts within the country. Five calibrated examiners carried out clinical examinations, recording caries experience at the dentine threshold (BASCD criteria) and presence or absence of sealants along with Socio-demographic indicators associated with oral health. Mann Whitney and Pearson's chi-square non parametric tests were utilized for assessing the data. The level of significance was p < 0.05. RESULTS: Sealants utilization varied considerably within the different districts, with 8,3% of the 12 and 8,0% of the 15-year-old adolescents having at least one sealed molar. Sealants reduced DMFS scores by 11% in the 12-year-olds and by 24% in the 15-year-olds, while 15-year-old adolescents from rural areas had a statistically significant (p = 0.002) less chance of having sealants (71%) compared to children from urban areas. Girls had higher chance to receive sealants in both age groups (26% for the 12 and 19% for the 15-year-old) as well as patients that visited the dentist for prevention compared to those visiting the dentist because they thought they needed a restoration or because they were in pain. CONCLUSIONS: The finding that sealants reduced DMFS scores despite their very low utilization, along with the high prevalence of dental caries found on the occlusal surfaces of the posterior teeth of Greek adolescents, is calling for a national preventive program with sealants which could eliminate caries to a larger extent.