Biomedical subjects

M Lapter

Publications and source records attributed to M Lapter.

6 recordsLinked to original sources

PubMed2004

[Verification of maxillary and mandibular asymmetry via orthopantogram's analysis].

AIM: The purpose of this study was to analyse the homologous variables' symmetry (horizontal, vertical, angular and of area surface) of the right and left segment in the maxilla and in the mandible of subjects with a normal occlusion and a malocclusion. METHODS: Two-hundred and two orthopantomograms were analysed (162 with malocclusion, 40 with normal occlusion). These points of reference were used: orbital, condilion, gonion, menton, point A (intersection point between the vertical line passing through the centre of the nasal septum and the horizontal line which links the 2 points O), point B (intersection point between the mandibular margin and the vertical line passing through point O) and point T (intersection point of A-Cn on the maxillary tuberosity). RESULTS: This study did not confirm any statistically significant differences between the right and left analysed variables studied in both groups. CONCLUSION: Orthopantomography may be a useful test in the screening for facial asymmetry.

Adult↗

PubMed2000

Change in the inclination of the occlusal plane during craniofacial growth and development.

The aim of this study was to examine the change in the occlusal plane inclination that takes place during craniofacial growth relative to various facio-cranial reference lines, as well as to find possible differences in means between sexes, to determine if there were correlations among variables, and to find out which of the parameters were the most reliable in determining the occlusal plane inclination. The investigation was carried out on 192 lateral radiographs of subjects divided into five age groups. The radiographs were traced and six angular roentgencephalometric variables were analysed by using different reference lines: cranial base (OLNS), Frankfort horizontal (OLFH), maxillary base (OLPL), mandibular base (OLML), anterior face height (OLNM) and posterior face height (OLSGO). It could be concluded that the change in occlusal plane inclination shows anterior rotation (left profile) during growth. The most significant change of the occlusal plane inclination was found using variables OLPL, OLFH and OLNS. There were no significant differences according to sex. Small but significant correlations were found between all investigated variables, except OLML.

Adolescent↗

PubMed1999

Computer analyses of two active plate modifications.

The aim of this study was to determine tooth movements in the upper dental arch using a simulated original model during the time of activation of two active plates modifications, symmetrically and asymmetrically cut plates. The changes of the dental arch dimensions and precise evaluation of the distribution of the forces produced by appliance were analysed by recording tooth movements. In order to register tooth movements more precisely two referral points were notched on each tooth thus creating 38 variables which defined weight and lengths of the dental arch. The symmetrically cut active plates used to obtain transversal expansion affect equally both sides and cause symmetrical movements of premolars, less of molars and canines, whereas they have no effect on incisors. The asymmetrically cut active plates used to obtain transversal expansion affect more the side of smaller active part of the plate. Movements are larger at the premolars than at molars and canines, and minimal at incisors. The results of this study confirm the data from the literature and a logical interdependence of the force and movements thus emphasising the importance of anchorage in orthodontic therapy.

Computer Simulation↗

PubMed1998

Inheritance of hypodontia in twins.

The aim of this study was to establish prevalence of hypodontia in the twin sample and to assess the degree of its heritability. A study was performed in a sample of 96 twin pairs, 38 pairs being monozygotic (MZ) and 58 pairs dizygotic (DZ), from north-west Croatia. The sample included 25.82% of all twins born in the region during a ten-year period. The twin zygosity was determined according to the WHO recommendations (1996). A revised Holzinger's index (Hc') according to Allen was applied to calculate the degree of heritability. Hypodontia was found in 22 out of the total of 192 twins analyzed (11.5%). Among 96 pairs of twins, hypodontia was observed in 17 pairs (7 MZ and 10 DZ pairs). Among the MZ, 4 pairs were found to be concordant for hypodontia, among the DZ one pair only. The heritability index was 0825. A prevalence of hypodontia in twins observed in this study is significantly higher than in the general population. A high index of heritability (Hc' = 0.825) points to a high genetic determination.

Adolescent↗

PubMed1998

Development of third molars in children in Istria.

The aim of this study was to determine the prevalence of third molars in children in Istria aged 7 to 18. The study was performed on 2350 panoramic radiographs of children in Istria that have been analysed and then divided into 7 age groups. Each of these groups consisted of the same number of boys and girls. It has been found that the development of third molars starts earlier in the mandible, and that before the age of 12 there are more third molars in the mandible than in the maxilla (p < 0.01). Nine-year old girls have statistically significantly more third molars than the boys of that age, but twelve year old boys have more than the girls. The differences in the prevalence of third molars between the jaw sides was statistically significant only for mandibles of twelve year old girls. Hypodontia of third molars has been found in 4.5% of boys and 5.8% of girls aged 14 to 18.

Adolescent↗

PubMed1998

Body height and weight and respiratory diseases in skeletal Class II/1 orthodontic patients.

The aims of this study were to determine if there is an increased incidence of respiratory diseases in patients with Angle Class II/1 skeletal intermaxillary relationship in comparison to eugnathic patients and if there is a difference of body height and weight between them. The sample consisted of 60 eugnathic subjects and 88 subjects with Class II/1. Girls were examined at an age of 6, 7, 8, 10, 13 and 14 and boys at an age of 7, 8, 9, 11, 14 and 15. All subjects underwent an orthodontic and medical examination in these time intervals. Data about their respiratory diseases as well as those about their height and weight were taken from their medical files in school dispensaries and were statistically analyzed. No statistically significant differences with regard to the frequency of respiratory diseases were found between eugnathic subjects and those with Class II/1. In almost all investigated time intervals subjects with Class II/1 were statistically significantly higher than the eugnathic subjects, but only in the 8-years old male group with Class II/1 the subjects were heavier than others. The results of this study suggest that patients with Class II/1 either have a faster growth pattern or belong to an asthenic constitution type.

Adolescent↗