Mean Age Of Eruption Research Articles

Chronology of Deciduous Teeth Eruption in Children with Cleft Lip and Palate

To determine the chronology and sequence of eruption of the deciduous teeth in children with complete unilateral cleft lip and palate. Cross-sectional study. Hospital for Rehabilitation of Craniofacial Anomalies, University of Sao Paulo, Bauru, Sao Paulo, Brazil. A total of 435 children aged 0 to 48 months who presented with complete unilateral cleft lip and palate. All teeth on the cleft side in both jaws for both sexes presented a higher mean age of eruption than their homologues at the noncleft side. This difference was statistically significant for the maxillary lateral incisor, maxillary cuspid, and mandibular lateral incisor. There was a statistically significant sex difference regarding the mean age of eruption only for the maxillary second molar for the girls and mandibular cuspid for the boys. The maxillary lateral incisor on the cleft side was the last tooth to erupt, thus modifying the sequence of eruption of the deciduous teeth. The results suggest the interference of the cleft on the chronology of eruption of the deciduous teeth that are directly related to it.

Age and sequence of eruption of permanent teeth in Kelantan, north-eastern Malaysia.

The aim of this study was to determine the age and sequence of eruption of permanent teeth, as well as gender differences, in children and adolescents in Kelantan, Malaysia. Cross-sectional data on permanent teeth eruption were collected by examining pre-school, primary and secondary school children of 5-17 years of age. The subjects were drawn by multistage random sampling from the school registers. There were 2,382 subjects in the sample, 1,062 boys and 1,320 girls. The data were subjected to probit regression analysis. The mean age of eruption of lower first molar was 6.0 (95%CI: 5.8, 6.2) years. The median age of eruption of each tooth was earlier in girls than in boys. Although the range of years during which the permanent teeth erupted was similar in both sexes, i.e. 6-12 years, the sequence of the tooth eruption differed. All mandibular teeth, with the exception of first and second premolars in both males and females, tended to erupt earlier than their maxillary counterparts. The findings seem to correspond to earlier studies done in the other parts of the world.

The chronology and sequence of eruption of human permanent teeth in Northern Ireland.

To ascertain the average and range of ages and sequence of eruption of human permanent teeth, taking into account the effect of premature loss of primary antecedents. Longitudinal study. Caucasian subjects in Northern Ireland. Study casts at 6-monthly intervals from age 5 to 15 years of 276 children (146 males and 130 females) enrolled in the Belfast Growth Study. The mean and range of ages of eruption of each individual tooth were computed. Comparisons were made between the mean ages of eruption with and without premature loss of primary antecedents, between upper and lower arches, between right and left sides and between males and females. The sequence of eruption was also investigated. The means and ranges of eruption ages are reported. Premature loss of primary antecedents delayed eruption of permanent successors except for the upper premolars which were accelerated. The differences relating to the upper first premolar and lower canine were not statistically significant. Each lower tooth erupted before its upper counterpart except for the premolars. There was no significant difference in age of eruption between right and left sides. Females tended to erupt teeth before males with the exception of the second molars in both arches; however, the only differences to reach statistical significance related to upper and lower canines and upper lateral incisors. The most frequent orders of eruption were unique to the subject. These occurred in 22% of upper and 33% of lower arches. The classic sequences: first molar-central incisor-lateral incisor-first premolar-canine-second premolar-second molar (M1-I1-I2-PM1-C-PM2-M2) in the upper arch and I1-M1-I2-C-PM1-PM2-M2 in the lower arch occurred in only 16% of upper arches and 13% of lower arches. Males adhered to the textbook sequence (20% upper, 17% lower) more than females (12% upper, 8% lower). In the upper arch of females, the order M1-I1-I2-PM1-PM2-C-M2 in 10% of subjects was almost as frequent as the classic sequence. The ages, ranges and orders of eruption found in this study are more reliable than many which are frequently quoted on account of its longitudinal nature and the fact that the effect of premature loss of primary antecedents is taken into account. The exclusively Caucasian sample makes the data quite precise but limits applicability to patients of this ethnic origin.

Zahneruption bei Jenaer Kindern in der ersten Phase des Wechselgebisses

Based on the process of tooth eruption in children of Jena during the first period of erupting permanent teeth secular changes of the dentition were investigated and the topicality of the current tables for dental age were checked. Mean age of eruption was computed for the individual types of teeth and for each sex in Jena's children and curves for eruption were constructed. On this basis population-specific standards for the dental age were calculated and the children were subdivided into "late, normal or early teether". By comparing the methods for age estimation using the number of teeth or the roentgenological method from Demirjian et al. (1973) it could be shown, that both methods lead to comparable results in the first period of permanent teeth eruption.

Eruption time of primary teeth in Iraqi children.

Abstract The mean times and order of eruption of primary teeth were determined cross‐sectionally from 1017 Iraqi nursery schoolchildren, ranging in age from 1 to 40 months. No statistical differences were found in the mean ages of eruption between corresponding right and left primary teeth in both sexes. The order of eruption for the maxilla and the mandible was the same in both sexes. In boys teeth erupted earlier than girls except for the maxillary central incisors and the mandible second molars.

Caries susceptibility of permanent first and second molars in children aged 5-15 years.

Clinical examinations of 276 5-year-old children were carried out twice yearly for 2 1/2 years, and a further 1104 11--12-year-old children were examined annually for 3 years. Fifty per cent of permanent first molar teeth had erupted by 6.4 years; the mean age of eruption for permanent second molar teeth was 12.2 years. One year after these mean eruption dates over 10% of first molars and 45% of second permanent molars were already carious. Although development of caries was initially slower in permanent first molars, between the ages of 7.5 and 8.5 years the caries increment rose to 18.8%. By the age of 15 years the DMF was 92% for first and 68% for second molar teeth. The missing and filled proportion of the total DMF rose consistently. This represents the amount of treated caries and exceeded the amount of untreated caries in permanent first molars at all age levels. The rate of caries initiation in the present investigation emphasizes that restorative programmes and preventive regimens for children must be based on frequent recall examinations of not more than 6-monthly intervals.

A serial study of the chronology of exfoliation of deciduous teeth and eruption of permanent teeth

The shedding of deciduous teeth has been studied in the serial records of 6-monthly examinations of 354 boys and 340 girls. The eruption of the permanent teeth has been studied from the records of cross section surveys of 1000 boys and 1000 girls. All examinations were conducted in a dental chair with good lighting after the mouth had been cleaned by hygienists. A tooth was considered erupted if any part of it was visible. The data on the deciduous teeth were presented in the form of a frequency table and only an elementary method of analysis was employed. Three methods of analysis were compared in the calculation of the mean ages of eruption of the permanent teeth; a graphic method, probit analysis and Kärbers method. The graphic method was proven of great value in the preliminary assessment of data and indicated whether the use of more complicated methods was justified; Kärbers method was preferred to Probit analysis. It was found that the pattern of shedding of the deciduous teeth was similar to the findings of Stones et al. (1957), both in the order of shedding the individual teeth and in the mean ages. The teeth were shed earlier from girls than from boys: some deciduous teeth were exfoliated between the ages of three years and four years. The mean ages of eruption of the individual permanent teeth were generally earlier than the findings of Ainsworth (1925), but similar to the findings of Clements, Davies and Pickett (1953). The mean ages of eruption of six permanent teeth were significantly earlier than the mean ages found by Ainsworth for the same teeth. This may be a phenomenon associated with the earlier onset of puberty as described by Charles (1958). No sex difference was found in the eruption of the canines and premolars.