Iluta Ion, dr. med., conf. univ. “Method of prognosis of dento-maxillary anomalies in children”

Abstract
The study was done with the scope of elaborating the methods of prognosis of dento-maxillary anomalies in children in the age group of 10-14 years. To elaborate the method, factors for prognosis of growth and development of dento-maxillary apparatus were used: upper inter premolar distance (P), lower inter premolar distance(Pm), upper inter molar distance(M), lower inter molar distance(Mm), the length of the anterior segment of the upper dental arch(Lo), mesio- distal dimensions of the upper incisors(DMI) and lower incisors(DMIm), number of erupted teeth((NDE). The median values of the parameters were determined. In the study, 490 children frorm the schools of Chisinau were examined. Depending on the risk of developing dento-maxillary anomalies, the children are classified in groups:
Group I – children with high risk of developing dento-maxillary anomalies consist of children with: Mm,M,Pm,P>Mo>DMI,DMIm,NDE,Lo
Group II – children with low risk of developing dento-maxillary anomalies consist of children with : Mm,M,Pm,P Children from Group I need provision of early prophylactic orthodontic treatment.
keywords: anomalies, children, prognosis.
Introduction
The problem of etiopathology and the treatment of dento-maxillary anomalies in children is a real problem in present times. Dento- maxillary anomalies or malocclusions are the third most common dental disease in children after dental caries and periodontal diseases. Analysis of epidemiologic data of dento-maxillary anomalies in several countries shows that this condition is encountered frequently. According to Tiominen M.L., Tiominen R.I. (1994 cit.Ф. Я. Хорошилъкина) [3], these abnormalities are found in 47% children and adolescent in Finland, in Denmark [5] – 45% (Burgersdijc KV, et alter, 1991), in Norway – 37% (Espeland LV, Steenvic A., 1991), in the U.S. [4] – 35%, in Russia [6] – 49%, in Ukraine – 75% (Udoviţcaia EV et al., 1993) in Romania – 41-49% (Sapira), 50-60% (Cocirla and collaborators), 75% (Eiru and Rusu) Dorobanţ V. , Stanciu D 2003 [1] in Moldova [2] – 35-58%. This pathology is present in the primary as well as mixed dentition, and if not treated at the time of growth and development is seen in the permanent dentition in a more accentuated and serious manner. This leads to increased orthodontic treatment time and increased costs of the treatment. Orthodontists perform orthodontic treatment and use appliances for retention for a long period of time without performing preventive treatment during the development of the anomaly.
Thus, developing methods of prognosis of the maxillary dental abnormalities in children and use of effective methods of prevention and early treatment are of prime importance in orthodontics.
Aim of the study
To develop a method for prognosis of maxillary dental abnormalities in children aged 10-14.
Objectives of the investigation
1. Study of biometric parameters: distance inter premolar , distance inter molar superior and inferior
2. Estimation of length of anterior segment of upper dental arch
3. Determination of mesio-distal dimensions of the upper and lower incisors
4. The appreciation of the rate of dental eruption by evaluating the sum of erupted teeth
5. Development of a scheme for prognosis of the risk of developing a dento-maxillary anomaly.
Materials and methods
According to the goals and objectives of the work, 490 children were examined in high schools from Chisinau, in the age group of 10-14 years(fig. 1). The following parameters were calculated and analysed : inter premolar distance superior(P) and inferior (Pm). Inter molar distance superior(M) and inferior(Mm). length of the anterior segment of the upper arch(Lo). Mesio distal dimensions of the incisors superior(DMI) and inferior(DMIm). Number of erupted teeth(NDE). The parameters were determined intraorally. The teeth in the phase of eruption were taken as erupted. Median values(Mo) of the above parameters were determined depending on the age and sex. The following parameters were used for dividing the children in groups : M,Mm,P,Pm. The children were classified in 2 groups depending on the values of the parameters:
Group I – with high risk of developing a dento-maxillary anomaly which is constituted of children with
Mm,M,Pm,P>Mo>DMI,DMIm,NDE,Lo
Group II – with low risk of developing a dento-maxillary anomaly which is constituted of children with
Mm,M,Pm,P The degree of risk of developing a dento-maxillary anomaly was calculated by estimating relative risk. Investigations data were processed by methods of descriptive analysis, variation and regression study. Student t test and criteria of coherent selection was used to study the significant difference between the 2 groups.
Results and discussion
The analysis of the parameters studied depending on group affiliation showed significant discrepancy. For example, a decrease in inter premolar distance in the upper and lower arch was observed in boys aged 12 years in group I as compared to group II and accordingly these values were: the upper arch – 37.20 ± 2.49 to 31.40 ± 2.49 to 45.0 ± 2.48 cm and 37.20 ± 2.50 cm; in the mandibular arch: 34 , 27 ± 2.23 to 31.40 ± 2.27 to 41.90 ± 2.20 cm and 34.27 ± 2.27 cm. Similarly, a decrease in inter molar distance in the upper and the lower arch was observed in group I compared with group II and, accordingly, these values were: the upper arch 48.04 ± 3.14 to 38.60 ± 3.14 to 55.80 ± 3.44 cm and 48.04 ± 2.63 cm; in the mandibular arch: 49 , 03 ± 2.63 to 41.20 ± 2.63 to 55.50 ± 2.40 cm and 49.03 ± 2.87 cm. In group I there was an increase in anterior segment of the upper dental arch as compared to group II: with the parameters constituted: 17.82 ± 1.04 to 21.0 ± 1.01 cm and 17.82 ± 1.04 to 15.50 ± 1.08 cm. Mesio distal dimensions of the upper incisor teeth in children in group I: 3.04 ± 0.16 to 3.59 ± 0.13 cm in group II: 3.04 ± 0.16 to 2.60 ± 0.19 cm. Similarly, an increase in these parameters was also observed in the mandibular arch : Group I- 2, 24 ± 0.09 to 2.57 ± 0.11 cm and a decrease – in group II: 2.24 ± 0.11 to 2.02 ± 0.13 cm. In group I was a significant increase in the number of erupted teeth from group II and, accordingly, were: 24.97 ± 4.04 to 28.0 ± 4.15 and 24.97 ± 4.04 to 12.0 ± 4.83.
Thus, the study noted key disturbances in biometric parameters in both transverse and sagittal planes, mesio-distal dimension of the incisors and early tooth eruption in children.
Analysis of the results, demonstrated same trend in girls aged 12 years: decrease in upper and lower inter premolar distance , upper and lower inter molar distance, increase in the mesio-distal dimensions of the upper and lower incisors, anterior segment length of upper dental arch and number of teeth erupted in the group I group II(fig2,3).
Comparative values of biometric parameters in boys aged 13 years have also demonstrated an essential difference: boys in group I with an inter premolar distance of 35.59 ± 4.09 to 32.90 ± 4.09 to 38.0 ± 2.11 cm and 35.59 ± 2.11 cm, and the mandibular arch: 35.64 ± 2.02 to 30.60 ± 2.20 and 35.64 ± 2.02 to 40.20 ± 1.85 cm. In the upper arch inter molar distance was found to be: 47.99 ± 3.37 to 41.30 ± 3.37 to 53.40 ± 3.92 cm and 47.99 ± 3.37 cm.and in the mandibular arch: 48.68 ± 2.57 to 41.81 ± 2.34 and 48.68 ± 2.57 to 53.0 ± 2.70 cm. Anterior segment length of upper dental arch observed in group I: 17.71 ± 0.88 to 19.10 ± 0.88 to 15.10 ± 0.82 cm and 17.71 ± 0.91 cm – in group II. In boys, the sum of mesio-distal dimensions of incisor teeth in group I: 3.06 ± 0.16 to 3.30 ± 0.16 cm and 3.06 ± 0.16 to 2.60 ± 0.17 cm – group II, the same indices in the mandibular arch in group I: 2.28 ± 0.24 to 2.64 ± 0.26 cm in group II: 2.28 ± 0.24 to 2.64 ± 0.26 cm. The number of erupted teeth in group I showed an increase : 26.73 ± 3.53 to 28.0 ± 2.93 compared to group II: 26.73 ± 2.93 to 24.97 ± 3 , 53.
Analysis of the results, demonstrated same trend in girls aged 13 years: decrease in upper and lower inter premolar distance , upper and lower inter molar distance, increase in the mesio-distal dimensions of the upper and lower incisors, anterior segment length of upper dental arch and number of teeth erupted in the group I group II(fig4,5).
Analysis of the biometric parameters, mesio-distal dimensions of upper and lower incisors ; number of erupted teeth, length of anterior segment of the upper dental arch in boys and girls ages 10-11 years showed the same trend(fig. 6,7).
So, biometric study revealed essential disorders in children with accelerated dental eruption and increased mesio-distal dimensions of the incisors. These were manifested by disproportions in the dental alveolar arch, which demonstrates the lack of space in the maxillary dental arch and therefore causes development defects.
The majority of dento-maxillary anomalies and malocclusions are a result of premature eruption of permanent teeth which occupy an abnormal position in the arch because of lack of sufficient space for their correct positioning[3].
When there is an asynchronism between skeletal development and eruption of teeth, they appear before the necessary length of the arch is achieved for alignment.
There is no synchronization between the evolution of the dentition and the skeleton, the two systems, bone and tooth, grow completely independent. Development and skeletal growth lags by 1-1.5 years compared to teeth eruption.
Accelerated tooth eruption, as one of the components of acceleration of somatic development, the system determines the imbalance between dental and maxillo-facial mass. This disparity is caused by lack of synchronization between teeth and the skeleton, the two systems – skeletal and dental. Dento-maxillary disharmony is influenced by the persistence of disproportion between the mesio-distal size of the permanent teeth and dento-alveolar arch perimeter.
Meanwhile, asynchronism of biological age and eruption can cause retardation of bone growth and development of arches, influenced by individuality and independence of growth and development of these two systems- dental and alveolar process.
Conclusions
1. Predicting the development of dento-maxillary in children aged 10-14 years can be done using the prognostic factors of growth and development of the dento-maxillary complex: upper and lower inter premolar distance, inter molar distance, anterior segment length of upper dental arch; mesio-distal dimensions of the upper and lower incisors, the number of teeth erupted.
2. The method of prognosis allows to select children depending on the risk of development of dento-maxillary anomaly in groups :
Group I – group of children at high risk of development of dento-maxillary anomaly, which consists of children with
Mm,M,Pm,P>Mo>DMI,DMIm,NDE,Lo

Group II – group of children with low risk of development of dento-maxillary anomaly, which consists of children with
Mm,M,Pm,P

3. Children in group I at high risk of development of dento-maxillary anomaly require early initiation of prophylactic orthodontic treatment.
References :
1.Dorobăţ V., Stanciu D. Ortodonţie dento-facială. Editura Medicală, Bucureşti, 2003, 501p.
2.Iluţă I., Buşmachiu I. Anomaliile dento-maxilare la copii şi adolescenţi în Republica Moldova,Medicina Stomatologică, Chişinău, 2011, N. 4, p.28-30
3. Iluţa I. Concepţie nouă despre etiopatogenia anomaliilor dento-maxilare. Medicina stomatologică, Chişinău, 2010, №3, p.111-112
4.Proffit., Fieds H. Contemporany Orthodontics, Mosby Yeir Book, 1993
5.Rolling S. Oral Epidemiol., 1978, 6, 145-15
6.Ф.Я. Хорошилкина (ред.) Ортодонтия, М, 2006, 541с.

Comments are closed.