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Biomedical subjects

I Brin

Publications and source records attributed to I Brin.

At least 19 recordsLinked to original sources
PubMed2003

Periodontal status following surgical-orthodontic alignment of impacted central incisors with an open-eruption technique.

Several factors may affect the outcome of the orthodontic/surgical modality for the resolution of impacted central incisors, but particularly the manner in which the impacted tooth is exposed. The present study aimed to evaluate the post-retention clinical appearance and periodontal status of impacted maxillary central incisors which were exposed and aligned with an open-eruption surgical-orthodontic technique. Twelve subjects (four males, eight females), aged 22 years (range 15-38 years), previously treated for a unilateral impacted central incisor (ICI), were examined 10 years (range 3-25 years) post-retention. A split-mouth method was used for the comparison with the unaffected side. One treated central incisor exfoliated 10 years post-retention, thus the results were based on the remaining 11 patients. Statistically significant differences were found between the affected and control incisors in most of the periodontal parameters measured, although some were small and of minimal clinical importance. The increase in the mesio-labial pocket depth was associated with a highly significant 10 per cent reduction in bone level at this site (P = 0.007). A highly statistically significant increase in crown length (P < 0.001) and a reduction in the width of the attached gingiva (P = 0.005) were seen in these previously impacted teeth. An abnormal gingival contour was present in eight treated incisors and positional relapse in five cases. It is concluded that the convenience of the open-eruption technique must be weighed against the long-term negative aesthetic and periodontal effects on the treated tooth, although the findings of this study should be viewed with caution due to the limited sample size.

Adolescent↗
PubMed2003

[A retrospective study of orthodontic treatment of children with clefts].

OBJECTIVES: To evaluate the population of cleft patients treated in a Department of Orthodontics and the types of treatment modalities provided. METHODS: Demographic, cleft related and treatment related data existing in the patients' files were supplemented by questionnaires. Comparisons were conducted among 3 cleft groups: cleft lip (CL), cleft lip and palate (CLP) and cleft palate (CP). RESULTS: The response rate was 36% (n = 152). The distribution of the patients in the 3 cleft groups, the sidedness, the male predominance and association with additional anomalies were similar to the reports in the literature. Most of the patients were the 3rd born (or more) and were of normal birth weight. Consanguity in the cleft families was at least 2.5 times more prevalent than that of the Israeli population and 30% reported on additional cleft in the family. Low birth weight and additional anomalies were found mainly in the CP group. Orthodontic involvement spanned 3 developmental periods: immediate postnatal presurgical treatment, phase I between the ages 6-8 years and full orthodontic treatment at a later age. Up to the age of 5 years only one lip operation was performed for 60% of the lip-affected children and one palate operation for 65% of the palate affected patients. CONCLUSIONS: 1. The distribution of the various cleft-related parameters in this retrospective study was similar to the findings in the literature. 2. The high prevalence of additional anomalies found emphasizes the need for a thorough examination of the cleft babies. 3. Orthodontic treatment was rendered in one and two phase protocols in addition to immediate postnatal pre-surgical intervention.

Age Factors↗
PubMed2001

Histomorphometric study of the periodontal vasculature during and after experimental tipping of the rat incisor.

The periodontal vasculature encircling the entire length of the rat lower incisor was studied at the time of tipping movement and 3 months later. In 12 rats (212+/-4 g b.w.), loads (0.19+/-0.016 N) were applied to the lower left incisor in a linguointrusive direction. After 2 weeks of loading, six experimental animals were killed with the loading springs in place. The springs were removed in the six remaining rats, which were killed 12 weeks later. Six additional rats with intact teeth served as control. All incisors were fixed, demineralized, embedded in glycol methacrylate and cross-sectioned perpendicular to the long axis of the tooth. The distance of each section (2 microm) from the apex was calculated. A computerized image-analysis program was used to measure the width and area of the labial and lingual periodontal ligament to establish whether the measured segments corresponded to the compressed or expanded zones. In each cross-section, the various types of blood vessels were counted and the cross-sectional area of all venous vessels was measured. The results showed that after 2 weeks of loading (1) the general trend of vascular changes was similar under pressure and tension; (2) the large-diameter vessels were unaffected by loading; (3) the mean number of terminal arterioles had decreased significantly, while the number of capillaries and postcapillary venules had increased significantly in the apical tooth part; (4) the venous blood vessel area had decreased significantly in the apical tooth part; (5) the intensity of the vascular reaction was dependent on the degree of tissue distortion; and (6) after 12 weeks' recovery the vascular changes were still present, demonstrating a rebound effect. The findings suggest that microvascular alterations following tooth loading are not directly related to the spatial effect of loading itself and are of a much longer duration than expected.

Animals↗
PubMed2001

Can maxillary incisor trauma be predicted from cephalometric measurements?

Dental injury is a traumatic event related to many factors, including dentofacial morphology. In a previous study in which we used a logistic regression model, 5 cephalometric variables were defined as being the best predictors of traumatic injury. The purposes of this study were to test the predictive value of the logistic regression analysis results for the occurrence of dental injury in a new patient sample and to compare these results with the outcome based on a visual evaluation of cephalograms. The study population consisted of 2 groups of orthodontic patients: patients with injured incisors (n = 64) and patients with non-injured incisors (n = 90). Cephalometric skeletal, dental, and soft tissue measurements were made. In addition, 6 professional judges visually evaluated all cephalograms. Classification tables were constructed for the results of the logistic regression model and for the assignment of patients according to the visual evaluation of the cephalograms. The percentage of correctly classified patients at the.7 probability level was 62%. Surprisingly, the professional panel rendered an equal predictive value. The relatively inferior performance of both the mathematical model and the "eyeballing" may demonstrate that dentofacial morphology is only partially responsible for susceptibility to trauma.

Cephalometry↗
PubMed2001

The labiogingival notch: an anatomical variation of clinical importance.

BACKGROUND: The labiogingival notch is a developmental phenomenon affecting the maxillary central incisors. Clinically, it can be easily misdiagnosed and improperly treated. Thus, it is important for dentists to recognize this condition. CASE DESCRIPTIONS: The authors describe two cases of misdiagnosed labiogingival notch on a maxillary central incisor. In one case, the notch was misinterpreted as a carious lesion and placement of a restoration was advised. In the second case, external resorption was suspected and forced eruption of the incisor was requested. In both cases, no treatment was needed. CLINICAL IMPLICATIONS: Misdiagnosis of this developmental phenomenon may lead to unnecessary invasive interventions. Because of this, clinicians need to be aware of this clinical variant.

Adolescent↗
PubMed2000

Profile of an orthodontic patient at risk of dental trauma.

Increased overjet and inadequate lip coverage of the maxillary incisors are considered significant risk factors in many clinical studies. The purpose of the present study was to examine this issue of dental injury by actual cephalometric measurements in orthodontic patients. Pretreatment cephalograms (taken with lips in repose) of consecutive patients were used. The patients were allotted to two groups Group T (trauma): 56 patients who had injured their maxillary incisors prior to their orthodontic treatment, mean age at the start of treatment 11.9 years (SD = 1.5); and Group C (control): 98 patients with intact maxillary incisors, mean age at the start of treatment 11.6 years (SD = 1.3). Twelve cephalometric landmarks on the soft and hard tissue profile were identified and digitized and the relevant dental, skeletal and soft tissue measurements recorded. The variables in Groups T and C were compared and their predictive values for possible occurrence of trauma were tested by logistic regression analysis. No statistically significant differences between boys and girls were found. Overjet or maxillary incisor exposure or interlabial gap, each as a single variable, could differentiate between the two groups. Logistic regression analysis indicated that only a small percentage (28.7%) of the dependent variable variation (trauma vs control) can be explained by interlabial gap, gender, upper incisor long axis to facial plane (degree), upper incisor long axis to interlabial gap and overjet.

Cephalometry↗
PubMed2000

Classification of occlusion reconsidered.

Katz's quantitative modification of Angle's occlusion classification has been found to have a high intra- and inter-examiner agreement among orthodontists. In the present study an attempt was made to introduce a 'combined' system comprising Katz's modification and overjet/overbite millimetric measurements in order to attain a more meaningful and complete classification of malocclusion than is presently available. A group of 32 raters (16 orthodontists and 16 senior-year students) examined 14 study models twice, with an interval of at least 1 month between examinations. In total, 448 x 2 determinations were performed. The percentage agreement of the Angle, the modified and the 'combined' systems, as well as the performance of the orthodontists versus the students were compared using the paired t-test. The percentage agreement obtained by both orthodontists and students was highest for Katz's modification and lowest for Angle's method. The overjet/overbite measurements affected the agreement in Katz's modified technique. The orthodontists surpassed the students with respect to Angle's method (P = 0.025), whereas no statistically significant difference existed between orthodontists and students regarding Katz's modification or the 'combined' system. It is concluded that in view of the relatively low agreement in the 'combined' method, it cannot be recommended for clinical application. The Katz's modified method, on the other hand, may be a helpful supplement to Angle's classification.

Cephalometry↗
PubMed1998

Does a secular trend exist in the distribution of occlusal patterns?

The existence of a secular trend in the distribution of occlusal patterns was studied in two generations of children. Study models and demographic data of a sample of 265 children from the previous generation (group A) and recordings of clinical examinations of 988 children from the present generation (group B) served as the data base for this study. Children in whom caries affected the occlusion and those in the deciduous dentition stage were excluded. Thus, occlusal analysis was performed for 102 children in group A and 703 in group B. A dramatic decrease was found in the prevalence of caries affecting the occlusion. No difference existed between the two groups with respect to molar and canine anteroposterior relationships. However, there was a decrease in the prevalence of normal occlusion accompanied by an increase of Class I malocclusion.

Adolescent↗
PubMed1998

A cephalometric evaluation of craniofacial morphology in familial dysautonomia.

OBJECTIVE: The purpose of this study was to delineate the craniofacial and dentoalveolar morphology of patients with familial dysautonomia (FD) in order to contribute to the understanding of the association between progressive sensory and autonomic neuropathy and the characteristic appearance of the dysautonomic face. PATIENTS: The study group comprised 32 patients with FD (15 females and 17 males; mean age 10.8 years, SD 3.5 years, range 5.8-19.8 years). DESIGN: Lateral cephalograms from each patient were traced twice. The means of the two measurements were compared with homologous cephalometric normal values of ethnic-specific and classical norms from the literature. RESULTS: In some parameters, the craniofacial morphology of the FD group was significantly different from the classical norms. There was a pronounced retrognathism in the mandible and a steep mandibular plane angle. The skeletal features of FD patients more closely resembled those of their ethnic group, although they were more retrognathic, and the mandibular growth axis was more horizontal. The incisors of these patients were more retropositioned and retroclined than were those of their healthy counterparts. CONCLUSIONS: The results suggest an insufficiency of the expected dentoalveolar compensatory mechanism that usually helps to bridge skeletal discrepancies. It is postulated that the neuropathy is probably the important factor in the lack of this compensatory mechanism.

Adult↗
PubMed1997

Occlusal traits in a group of school children in an isolated society in Jerusalem.

The prevalence of occlusal features in 939 children, aged 6-13 years, belonging to an ultra-orthodox community of Jewish Ashkenazi descent living in Jerusalem was studied clinically. Sexual dimorphism was found for overjet, overbite, and habit practising. About one-quarter of the sample exhibited some degree of occlusal mutilation due to caries, thus creating a 'caries-affected' subgroup, the rest forming the 'caries-free' subgroup. In the latter set, normocclusion was scarce (7.4 per cent), Class I being the most frequent malocclusion (49.1 per cent). Caries had a significant effect on the symmetry of bilateral occlusal relationships, lower dental midline deviation, and on crowding/spacing conditions in the mixed dentition stage (except for the maxilla in late mixed dentition). The low prevalence of normocclusion can be attributed to genetic background, environmental influences and the definition attached to normal occlusion.

Adolescent↗
PubMed1997

Long-term follow-up of conservative treatment of severely traumatized maxillary incisors.

We present the case of a 26-year-old man who at the age of 9 suffered severe trauma to both maxillary central incisors. The underlying malocclusion was skeletal and classified as dental Class II/1 with severe crowding. Both the maxillary central incisors and the two lower first premolars were extracted and the patient was treated with an edgewise appliance for 2 years. Acceptable occlusal relationships were achieved following orthodontic and adjunctive treatment which consisted of reshaping the maxillary lateral incisors with composite materials and grinding the canines to resemble lateral incisors. A critical evaluation of the esthetic and functional results at the age of 26 years is presented.

Child↗
PubMed1996

Skeletal and functional effects of treatment for unilateral posterior crossbite.

Unilateral posterior crossbite (UPXB) is a common malocclusion, frequently presenting a lower midline deviation, accompanied by Class II subdivision relationships in final closure and a very high prevalence of the reverse sequencing (RS) pattern of jaw movement. These features often persist even after the elimination of the crossbite. The purpose of the present study was to examine in detail the morphologic, skeletal, and functional effects of the treatment for this malocclusion category. The experimental group consisted of 24 children in the mixed dentition stage with UPXB who were treated with removable expansion plates and a control group of 10 age-matched children with normal occlusion. Longitudinal follow-up revealed a stable dental maxillary arch expansion of at least 1.5 mm but a complete elimination of crossbite in only 50% of the cases. The frequent persistence of Class II subdivision relations and lower midline deviation that were not due to functional mandibular shift was striking. The pretreatment posteroanterior (P-A) cephalograms indicated reduced facial and maxillary widths. After treatment, the achieved maxillary width increase was greater than expected with normal growth. Longitudinal assessment of the mandibular movement response revealed by the electrognathograph showed a high prevalence of RS, which was reduced after treatment. In conclusion, (1) a higher than expected prevalence of skeletal transverse aberrations at the maxillary and zygomatic levels were found in the UPXB group; (2) the removable expansion appliance induces transverse growth of the maxilla; and (3) an inherent pattern of jaw movement is characteristic to the UPXB and does not change significantly with orthodontic treatment.

Case-Control Studies↗
PubMed1993

Resorbed lateral incisors adjacent to impacted canines have normal crown size.

The importance of detecting maxillary canine impaction is that it may compromise dental health, particularly since a small but significant proportion of impacted canines is associated with the resorption of the roots of neighboring teeth. It has been shown that the existence of small and peg-shaped lateral incisors is highly correlated with maxillary canine palatal impaction. To date, however, it has not been established whether the root resorption that occurs has a similar correlation or a predilection for one or other types of lateral incisor crown structure. Accordingly, a group of patients with buccally or palatally impacted canines, in which root resorption of the lateral incisor could be diagnosed roentgenographically, was examined and compared with a group of cases with palatally impacted canines, none of which showed root resorption, which served as controls. The mesiodistal crown dimension of the lateral incisor in the experimental group was found to be normal in all patients except three (13%), which was significantly different from the distribution of lateral incisor size in the control group (p < 0.001). In the majority of the cases, aggressive root resorption of the lateral incisor root had occurred. We would speculate that in these cases, the normal-sized and early developing lateral incisor root obstructs the deviated eruption path of the canine and consequently stands a considerably greater chance of being damaged by resorption.

Adolescent↗
PubMed1993

Trauma as a possible etiologic factor in maxillary canine impaction.

A chain of events in the development of the dentition following trauma is described. Shortening of the root of the lateral incisor or displacement of the tooth bud, both as a sequel to trauma, may affect the path of eruption of the adjacent canine after dental injury. Special attention should be paid to the further development and eruption of the directly and indirectly affected teeth.

Child↗
PubMed1993

Functional and morphological-occlusal aspects in children treated for unilateral posterior cross-bite.

Morphological and functional aspects were investigated in children with unilateral posterior cross-bite (UPXB) before and after treatment. Sixty-five patients with Class I malocclusion with UPXB in the mixed dentition stage (mean age 8.8 +/- 1.6 years) served as the experimental group and 10 children of comparable age, with normocclusion or very mild Class I malocclusion (without UPXB) served as controls. The morphological aspects were examined on a longitudinal basis while the functional recordings, by means of a sirognathograph, were performed in a cross-sectional fashion. Complete elimination of cross-bite was maintained in 61 per cent and was accompanied by a dramatic reduction in the prevalence of functional mandibular displacement. However, the prevalence of mandibular midline deviation related to the maxillary midline as recorded in the intercuspal position was not affected. In addition, the high prevalence of Class II subdivision relationships which accompanied the UPXB in the intercuspal position was resolved in 50 per cent of the cases only. The sirognathographic recordings of the masticatory pattern showed a very high prevalence of a 'reverse sequencing' type pattern before treatment which was significantly lower following the elimination of UPXB, but still notably higher when compared with the controls. Reasons for these results are suggested and possible inter-relationships between the morphological and functional aspects are discussed.

Child↗
PubMed1992

Cephalometric pattern of Jewish East European adolescents with clinically acceptable occlusion.

Knowledge of the normal dentofacial patterns of various ethnic groups is important for clinical and research purposes. The objective of this study was to describe the dentofacial pattern of one Jewish ethnic group and to compare it with accepted standards for other white populations. Lateral cephalometric radiographs of 18 children of Jewish East European origin with clinically acceptable permanent occlusion, ages 11 to 13 years, were used. A computer-aided cephalometric analysis was performed, and the mean values and standard deviations for the various cephalometric variables were obtained. When compared with some classical standards, it was found that this ethnic group tended toward a mild skeletal Class II, a convex profile, and a more vertical direction of growth. These features appeared in persons selected on the basis of a clinically acceptable occlusion, suggesting the existence of dental compensations. Understanding these natural accommodations of the dentition to skeletal variations can be clinically useful when establishing treatment goals.

Adolescent↗
PubMed1992

Quintuplets with clefts: follow-up at ten years of age.

A set of quintuplets, three of which were born with various degrees of oral clefting, were followed up to the age of 10 years. Study models, as well as panoramic and intraoral roentgenograms were collected at ages 5 and 10 years. Cephalometric roentgenograms were added at the age of 10 years. Analysis of the growth charts for height and weight indicated normal somatic development, save for a persistent, albeit diminishing, lag for the two most severely affected siblings. The latter also demonstrated a more vertical craniofacial growth pattern. The dental arch dimensions were within normal range, except for the maxillary and mandibular widths in the two more affected siblings, who also exhibited a delay of one or two stages of dental development in an intersibling comparison. These findings indicate that in the more severely affected siblings, there was only partial growth catch-up at the age of 10 years.

Cephalometry↗