Biomedical subjects

M Slaj

Publications and source records attributed to M Slaj.

At least 19 recordsLinked to original sources

PubMed2000

Orofacial analysis on the Adriatic Islands: 1. The island of Hvar as a model for odontogenetic researches.

This paper presents a preliminary orofacial analysis of a subadult population of Hvar, a Croatian island in the Adriatic. Its population represents one of the last genetic isolates in Europe and has therefore been the object of intensive crossdisciplinary research over the last 30 years. We focussed on the coefficient of endogamy on the one hand and malocclusal-related caries on the other hand, and expected differences in the latter between subgroups of the population. We analyzed 224 dental casts from children all over the island and found multiple caries in approximal surfaces in 55 percent of the children, but no significant differences between the subpopulations. Instead, significantly more caries affection was found in the boys than in the girls. The percentage of general caries affection is fairly high, even when compared to other isolated populations; it may be due to environmental influence. This would be consistent with the other results, which have putatively been caused by complex environmental influences and not solely by genetic components.

Adolescent↗

PubMed1999

Osteogenic effect of a gastric pentadecapeptide, BPC-157, on the healing of segmental bone defect in rabbits: a comparison with bone marrow and autologous cortical bone implantation.

Gastrectomy often results in increased likelihood of osteoporosis, metabolic aberration, and risk of fracture, and there is a need for a gastric peptide with osteogenic activity. A novel stomach pentadecapeptide, BPC-157, improves wound and fracture healing in rats in addition to having an angiogenic effect. Therefore, in the present study, using a segmental osteoperiosteal bone defect (0.8 cm, in the middle of the left radius) that remained incompletely healed in all control rabbits for 6 weeks (assessed in 2 week intervals), pentadecapeptide BPC-157 was further studied (either percutaneously given locally [10 microg/kg body weight] into the bone defect, or applied intramuscularly [intermittently, at postoperative days 7, 9, 14, and 16 at 10 microg/kg body weight] or continuously [once per day, postoperative days 7-21 at 10 microg or 10 ng/kg body weight]). For comparison, rabbits percutaneously received locally autologous bone marrow (2 mL, postoperative day 7). As standard treatment, immediately after its formation, the bone defect was filled with an autologous cortical graft. Saline-treated (2 mL intramuscularly [i.m.] and 2 mL locally into the bone defect), injured animals were used as controls. Pentadecapeptide BPC-157 significantly improved the healing of segmental bone defects. For instance, upon radiographic assessment, the callus surface, microphotodensitometry, quantitative histomorphometry (10 microg/kg body weight i.m. for 14 days), or quantitative histomorphometry (10 ng/kg body weight i.m. for 14 days) the effect of pentadecapeptide BPC-157 was shown to correspond to improvement after local application of bone marrow or autologous cortical graft. Moreover, a comparison of the number of animals with unhealed defects (all controls) or healed defects (complete bony continuity across the defect site) showed that besides pentadecapeptide intramuscular application for 14 days (i.e., local application of bone marrow or autologous cortical graft), also following other pentadecapeptide BPC-157 regimens (local application, or intermittent intramuscular administration), the number of animals with healed defect was increased. Hopefully, in the light of the suggested stomach significance for bone homeostasis, the possible relevance of this pentadecapeptide BPC-157 effect (local or intramuscular effectiveness, lack of unwanted effects) could be a basis for methods of choice in the future management of healing impairment in humans, and requires further investigation.

Animals↗

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

Computer assisted densitometric image analysis (CADIA) of bone density in periradicular bone defects healing.

CADIA can only be performed on geometrically standardized images converted in Al equivalents. The aim of this study was to develop the ability of the new CADIA software to quantify bone density on dental radiographs without previous standardization. A total of 36 examines with periradicular lesions were treated surgically, the defects were filled with Hydroxylapatite and followed up for 1, 6, and 12 months. Before and after surgery the operated areas were clinically evaluated using intraoral radiographs, tooth mobility index and relapses. Clinical results revealed satisfactory bone healing in 27 cases and relapses in 9 cases. The radiographs were then digitized with a high resolution CCD camera. Densitometric analysis was done in 10 points at the edge of the bone defect. Correction of geometric and brightness distortions was done with mathematical manipulation from three referral points positioned at the same place on each radiograph. Density values observed no bone loss in 23 cases and loss of bone in 13 cases. The differences between clinical evaluation and CADIA were not statistically significant.

Absorptiometry, Photon↗

PubMed1998

Computer anchorage analysis of digitized picture of modified typodont.

In contemporary orthodontic treatment, the extraction of a premolar is frequently indicated, followed by canine retraction with bodily movement. The main problem is how to prevent the mesial movement of first molars (loss of anchorage) and loss of the space obtained by extraction. The aim of the study was to evaluate the anchorage capacity of posterior teeth using SW (straight wire) appliances after extraction of first premolars and to determine Goshgarian transpalatal arch as anchorage reinforcement. All experiments were recorded by video-camera, and the analogue signal has been digitized and saved on PC. Computer animation visualised the direction and the amount of tooth movement. Very significant loss of anchorage was found (in the control experiment), when molars and premolars were reinforced. No significant difference between the active and non-active transpalatal arch has been perceived in the sense of lateral anchorage stabilization.

Humans↗

PubMed1998

Endocrinological status of patients with periodontal disease.

The aim of the present study was to determine whether changes in the endocrinologic status occur in patients with progressive forms of periodontal disease and, if so, what their role is. For this purpose the function of hypophysis, concentration of pituitary and accessory gland hormones, parathormone, calcium, phosphorous, glucose and lipids in blood were determined. The study was carried out in 77 subjects, 37 patients with advanced periodontal disease, and 40 control subjects with normal periodontium. Blood glucose was significantly lower in the study group (p < 0.01%) which was surprising, since increased glucose values are known to favor the development of periodontal disease. Growth hormone was significantly lower in the study group (p < 0.01%). Concentrations of parathormone calcium and phosphorous were also lower in the study group. Among sex hormones, only estradiol was found to have a significantly lower value in the study group (p = 0.92%). Although the values of nearly all hormones were within the reference range, the within-group analysis showed significant differences for some hormones. In general, these results were lower in subjects with advanced periodontal disease.

Adult↗

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↗

PubMed1997

Relation between cranial base flexure and position of the jaws.

Correlation between the cranial base flexure with the sagital and vertical positions of both jaws has been analysed on 180 radiographs of eugnathic probands and 256 radiographs of patients with various malocclusion forms. Radiographs were analysed by conventional cephalometric procedures determining maxillar rotation, mandibular rotation, sagittal position of the maxilla, sagittal position of the mandible, and cranial base flexure. A significant correlation between the degree of cranial base flexure and facial prognathism was found. The correlation coefficients were higher in eugnathic probands than in those with malocclusions. Regression analysis defined three basic types of sagittal bimaxillar relations: orthognatism, retrognatism and prognatism.

Adolescent↗

PubMed1992

Morphological cephalometric differences between two European populations.

Earlier research in craniofacial morphology of the inhabitants of Mainz (Germany) and Zagreb (Croatia), who represent the populations of wider areas, have shown some roentgen-cephalometric differences. The aim of this study is to determine the craniofacial morphologic differences of these populations in three dimensions. The sample consists of 200 adult examinees, male and female respectively, inhabiting the mentioned areas. The sample has been chosen so that the examinees with prominent craniofacial anomalies have been excluded. Twenty three craniofacial parameters with the usual anthropometric instruments have been measured. The data have been processed by using elementary descriptive statistics and discriminant analysis. The results have shown that in Mainz examinees longer and narrower heads and higher faces in comparison with Zagreb examinees, predominate. Significant differences in forehead widths and bipupilar distances have been found.

Adolescent↗

PubMed1991

[An analysis of craniofacial changes from deciduous to the first stage of mixed dentition].

Analysis has been done, with intention to observe dynamic of craniofacial changes, from deciduous to the end of the first phase of the mixed dentition. In the longitudinal sample, consisted of 67 children both sexes, observed from 3.5 to 8.5 year of age, the determined measurements of craniofacial variables, and indexes of the skull and face, were examined. The figures were elaborated statistically. Results show the slow reduction of the brachiocephals, while the frequency of mesiocephalics increases, especially at girls, what measurement of indexes confirm. From the deciduous period to the beginning of the mixed dentition, slow growth of the number of euriprosops and reduction of mesioprosops was found, while during the deciduous dentition the situation was opposite. Analysis of each craniofacial dimension shows that the length and the width of cranium are reduced until the beginning of the mixed dentition and increased after that. The other variables show continued increase of dimensions, especially at last period. Correlations are significant and very significant, between the width of the skull and the upper width of the face (and less significant at lower width of the face, which is in a high degree correlated with the height, than between the length of cranium and the height of the face. It is confirmed by factor analysis. At the multivariate analysis, two or three varimax factors can be isolated, dependent on phases: factor of wideness, factor of length height, and factor of age.

Cephalometry↗

PubMed1991

Orthodontic anomalies and differences in gnathometric variables in twins.

Actuality of gnathometric measurements by means of plaster casts persisting to the present days is stressed and the major research of the kind in twins mentioned. The study included 96 pairs of twins of both sexes (36 monozygotic and 60 dizygotic). Both qualitative and quantitative variables were evaluated and the results computer-processed. For most parameters evaluated, statistical processing revealed a markedly higher compatibility in monozygotes than in dizygotes. This held particularly true for types and severity of anomalies as well as for all qualitative variables, with the exception of over bite, overjet, class and class severity. The maxilla-related variables were shown to be highly genetically determined, which might be explained by the dynamics of mandibular movements and, possibly, a stronger effect of external factors on its growth and development.

Adolescent↗

PubMed1991

[Craniometric and gnathometric characteristics of anomalies Angle Class II in deciduous dentition].

The study was performed in 30 subjects with class II/1 and 30 subjects with class II/2 anomalies. The aim of the study was to assess the extent to which class II anomalies influenced individual craniometric and gnathometric dimensions as well as to determine whether there were any significant differences between the two subgroups. Craniometric dimensions were measured in each subject by means of standard measuring devices, while gnathometric analysis was carried out on plaster casts of their dental arches. Statistical processing was performed on an IBM PC-AT computer, with a SPSS/PC program support. The study results indicated the maxillomandibular and craniofacial growth to follow a specific pattern as early as in the deciduous dentition in subjects with class II anomalies. Differences between class II subgroups manifested in the range of the following parameters: all transversal craniometric dimensions were greater in class II/2, which was statistically significant in case of Eu-Eu dimension; height of the maxillary part of the face was significantly greater in class II/2; horizontal incisal step was significantly greater in class II/1; although all transversal dimensions of dental arches were considerably greater in class II/2, the differences were not statistically significant; the upper and lower dental arches were longer in class II/1 and II/2, respectively.

Cephalometry↗

PubMed1990

[Characteristics of the palate and palatine folds in twins].

In a sample of 95 pairs of twins (36 mz and 59 dz) the traits were analysed which define the shape of the palate, the intensity, direction and ramification of the plicae palati, the intensity and location of the raphae palati mediana and the shape and size of the papila incisiva. The impressions of the palates were made with optosil and these models were photographed. The photographs were analysed. The results indicate a significant genetic determination of the shape of the palate and the papilla incisiva and of the direction of the plicae palati. The analysed traits give the greatest values to the Hc index of inheritance.

Adolescent↗

PubMed1990

[The changes of the occlusal relationship from deciduous to the permanent dentition in the longitudinal sample].

The examination of the dynamics of the changes in sagittal, vertical and transversal occlusal relationship has been carried out on the sample of the 66 examinees of the both sexes. The children were examined for the first time at the age of 3.7 years, the again three times repeatedly (within a year) during the first period of the change of teeth. The occlusal changes were registered on the plaster models using the regular standard equipment. The results of the examination of the 4 gnathometric variables (class, overjet, overbite and the transversal occlusal relationship) have demonstrated the following: in 50% examinees the class remained unchanged; the total number of the examinees with class II as well as with uneven occlusal relationship, in the right and left quadrant have increased visibly; the early findings of class II have demonstrated very high stability; the inclination toward the increase of the overjet has been higher in the relation to the reduction; somewhat greater number has been recorded in the group on the overjet above 3 mm; overbite in the major part of the examinees has become deeper; the change from the open, tete a tete, minimal bite to the normal and deep bite has been recorded; the transversal occlusal relationship have remained unchanged in 60% of the cases; the frequency of the new transversal disarrangement in the mixed dentition has been three times higher in the relation to the earlier findings; also the cases of the spontaneous correction of the transversal disarrangement in the deciduous dentition have been recorded.

Child↗

PubMed1990

[Growth dynamics of the four main craniofacial dimensions in relation to orthodontic finding--a longitudinal study].

Analysis of growth dynamics of the four main craniofacial dimensions at the transition point from primary into mixed dentition was performed in order to better determine the effect of individual orthodontic anomalies starting to manifest at that time, on the direction and extent of the alterations observed. A sample consisting of 73 children aged 3.5-5.5 years, free of any overt symptoms of orthodontic anomalies, were re-examined at the age of 6.5-8.5 years and divided into groups according to orthodontic findings then obtained. Mean values (and their differences) of the defined parameters obtained on the first and second measurement were analyzed, both for the sample in total and separately, according to the orthodontic findings in mixed dentition. Based on this data, specific relationships between alterations in each craniofacial dimension and maxillary morphology, specific for particular anomaly, were determined. In the group free of growth dynamics anomalies, both facial and both cranial parameters were almost identical. More or less expressed alterations of a single facial or cranial parameter in dysgnathic subjects may have been related to oral symptoms of the respective anomaly. At the same time, results obtained in the study suggested the size of the four main craniofacial dimensions to differ as early as in primary dentition, and become grouped, depending on the development of future orthodontic anomaly.

Cephalometry↗

PubMed1990

[Dimensions of deciduous and permanent incisors in cases with Class II division 1 and 2 malocclusions].

The analysis of mesiodistal dimensions of the upper and lower incisors (in total and separately) has been carried out in order to investigate the interdependence of sizes of the teeth with defined malocclusions. The investigation included 180 cases of both sexes, out of which 90 had deciduous dentition and other 90 examinees had permanent dentition. There were 120 examinees with Class II malocclusion (60 with Class II/1, and 60 with Class II/2), whereas the rest of 60 examinees with normal occlusion were used as the control group. Gnathometric measurements were made on the plaster casts with calipher precision of 0.1 mm and were double checked. Computer analysis of the results obtained emphasized the following: the heterogeneity of findings in the deciduous dentition does not allow hypothesis of a connection between sizes of the deciduous incisors and defined malocclusions; in the permanent dentition the examinees with Class II division 1 malocclusion have significantly the largest incisors, and the smallest the examinees with class II division 2 malocclusion; the greatest difference in the size between the deciduous and permanent incisors was found in the examinees with Class II division 1 malocclusion and the smallest difference was found in the examinees with normal occlusion.

Adult↗