Secular trend of earlier onset and decelerated development of third molars: evidence from Croatia.

The purpose of this study was to evaluate the influence of the secular trend on development of third molars in 30 years period in Littoral region of Croatia. A total of 1103 panoramic radiographs of subjects aged from 6 to 18 years were analysed. First group comprised 531 panoramic radiographs (258 girls) taken from year period 1977 till 1979 and second group 572 radiographs (325 girls) taken from year period 2007 till 2009. Demirjian's method was used to determine the developmental stage of third molars. A secular trend in 30 years period was observed as earlier onset of third molars development in boys (6 months on average maxillary and 11 months mandibular) and girls (6 months for maxillary and 4 months for mandibular). Now-a-days, an increase in mineralisation for one Demirjian stage occurs at a slower pace of 5.2 months in boys and 3.4 in girls in maxilla and 2.3 or 2 months in mandible for boys and girls, respectively. The study showed a secular trend present as earlier onset but decelerated development of third molars in both genders and both jaws.

Secular trend in the development of permanent teeth in a population of Istria and the littoral region of Croatia.

The study evaluated secular trends in dental development during a period of 30 years, correlation between dental and chronological age in Istria and the littoral region of Croatia. The sample consisted of 1000 panoramic radiographs of children, aged 6-16 years (mean 10.0±1.8), taken in the period 1977-1979 (N=500; 243 females) and 2007-2009 (N=500; 299 females). Dental age was assessed according to Demirjian's method. Correlation between chronological and dental age was linear, positive, high, and statistically significant in both periods and genders, ranging from 0.73 to 0.86. Dental age was underestimated when compared to chronological age by 1 year on average, more 30 years ago (-1.35±1.17) than today (-0.63±1.09), less for girls (-0.80±1.22) than boys (-1.21±1.10). A statistically significant positive secular trend in acceleration of dental development was present of 0.72 years during the 30-year period and was more significant in girls than boys (0.83- and 0.51-year acceleration).

Dental health and dental care in children with cerebral palsy.

The aim of this study was to determine a difference between children with cerebral palsy (CP) and healthy children, regarding health condition of teeth and oral tissuses. Disfunction of masticatory system, in children with CP, causes many problems with mastication. Nonfunctional mastication is related with the consumption of mushy food and decreased selfcleaning of occlusal and aproximal surfaces. All that leads to higher incidence of dental caries. Comparing the DMTF/dft (decayed, missing, filled tooth) index, it is evident that there is no statistically significant difference in a tooth morbidity between the group of healthy children and group of children with CP. The healthy children have statistically significant more teeth with fillings with respect to children with CP. Extractions are more common in children with CP. There is no statistically significant difference between those two groups regarding decayed teeth, one of components of DMFT index. Decayed components are more common than the extractions and fillings in both groups, which shows the insufficient curative care for all children in both groups. It can be concluded that there is a certain need of early beginning and a better organization of the preventive pediatric and dental care, in order to decrease the appearence of dental decay and increase the level of dental health, in this challenged population.

Health condition of first permanent molars in year 1977 and 2007 in children in Istria (Croatia).

The aim of this study was to examine differences between health condition of the first permanent molar (M1) in children in 1977 and 2007. The materials for the study consisted of data on the health condition of M1 determined in a study in 1977 (Group I) for children from the district of Buje in Istria. The health condition of M1 was examined again in the same area in 2007 (Group II). The first permanent molar is most frequently affected by caries and represent a good indicator for general caries incidence of children. Study included 709 subjects in Group I (363 boys, 346 girls) and 460 subjects in Group II (242 boys, 218 girls), aged from 6 years and 0 months to 12 years and 5 months. The difference in the frequency of intact, decayed, filled and missingd M1 was examined in both groups. Chi2 test was used to determine the differences between the number of I (intact), D (decayed), F (filled) and M (missing) teeth for each age group in Group I and Group II. In Group I there were 29.3% intact, 48.9% decayed, 17.4% filled and 4.3% missing M1, and in Group II there were 53.0% intact, 22.6% decayed, 22.1% filled and 2.1% missing M1. During the period of 30 years, a significant increase of number of dental surgeries, and thus better preventive and health education, resulted in the significant increase in the number of intact (24.0%) and filled (4.7%) M1, and decrease in the number of decayed (26.3%) and missing (2.2%) M1. From 1977 to 2007, the number of intact M1 in group II increased considerably according to group I, while the number of decayed M1 in group II significant decreased according to group I. These changes were the result of a considerably increased number of dental surgeries.

The reliability of chronological age determination by means of mandibular third molar development in subjects in Croatia.

The aim of this study was to determine the development of the mandibular third molar and its relation to chronological age. The evaluated material consisted of 979 orthopantomograms of patients of Croatian Caucasian origin aged between 5.7 and 14.6 years. Third molar developmental stages were evaluated according to the stages proposed by Nolla. The frequencies of different stages of mineralization and the mean value of the mineralization of the mandibular third molars with regard to age, gender, and size of the mandible were determined and the coefficient of correlation determined between the age of the subject and the stage of development of the mandibular molars. Statistically significant correlation was determined between mineralization of the mandibular third molar and chronological age of the subjects (boys, mandibular left third molar r = 0.779, right third molar r = 0.793; girls, mandibular left third molar r = 0.746, right third molar r = 0.725). It can be concluded that the accuracy of age estimation based on Nolla's method is applicable for Croatian children.