Biomedical subjects

Faraj Behbehani

Publications and source records attributed to Faraj Behbehani.

10 recordsLinked to original sources

PubMed2006

Prediction of mandibular third-molar impaction in adolescent orthodontic patients.

INTRODUCTION: The purpose of this study was to identify risk factors for mandibular third-molar impaction in adolescent orthodontic patients. METHODS: Radiographs made before (T1) and after (T2) treatment and at least 10 years postretention (T3) of 134 patients that allowed accurate diagnosis of impaction vs eruption of at least 1 mandibular third molar were evaluated. RESULTS: Univariate logistic regression analyses at T1 showed that the decision to extract premolars (P <.05), an increase of 1 mm in mesial molar movement (P <.05), and an increase of 1 mm in eruption space measured from second molar to Xi point (centroid of the ramus) (P <.01) reduced the risk of impaction by 63%, 22%, and 30%, respectively. An increase of 1 degrees in mandibular third-molar angulation relative to the occlusal plane increased the risk of impaction by 11% (P <.01). Multivariate logistic regression analyses at T1 showed that reduced eruption space (P <.01), signs of forward mandibular growth rotation (P <.01), and female sex (P <.05) increased the risk of impaction. However, association tests documented increased frequencies of extractions and more mesial molar movement in female patients with erupted third molars. Univariate logistic regression analyses at T2 showed that every millimeter of increase in eruption space measured from the second molar to the anterior border of the ramus and to Xi point reduced the risk of impaction by 29% and 22%, respectively (P <.01), whereas every degree of increase in the angle between the occlusal surface and the occlusal plane increased the risk of impaction by 11% (P <.01). Multivariate logistic regression analyses at T2 showed that increased eruption space reduced the risk of impaction (P <.05), whereas increased mesial angulation of the third-molar bud (P <.01) and signs of forward growth rotation (P <.05) increased the risk of impaction.

Adolescent↗

PubMed2006

Racial variations in cephalometric analysis between Whites and Kuwaitis.

The objective of this study is to determine whether (1) Kuwaiti adolescents differ from Caucasian adolescents with respect to their cephalometric values; (2) sex plays a role in the differences between the two groups; and (3) a need exists to develop cephalometric standards for the Kuwaiti population. Standardized cephalometric films were obtained from 36 Kuwaiti females and 32 Kuwaiti males between the ages 11 and 14 years. Only subjects with Class I molar occlusion and a positive overjet of no more than 4 mm were selected. Each subject was age matched with White cephalometric values. Intraexaminer error, paired, and two-sample t-tests were made. The results show that there were significant differences between the Kuwaiti population and the Caucasian population for the majority of the variables tested (P < .01). Sex produced no significant effect on any of the variables studied. The Kuwaiti population has fuller lips, more facial convexity, greater dental protrusion, a more retruded and smaller mandible, and shorter posterior face height than the Caucasian population.

Adolescent↗

PubMed2006

Lateral cephalometric norms for adolescent Kuwaitis: hard tissue measurements.

OBJECTIVE: The purpose of this study was to establish lateral cephalometric hard tissue norms for adolescent Kuwaitis and to compare them with published norms. SUBJECTS AND METHODS: Digital lateral cephalograms were made of 162 Kuwaitis (82 boys and 80 girls of mean age 13.27 +/- 0.42 years and 13.21 +/- 0.43 years, respectively), with almost ideal occlusion. Anatomic landmarks were identified directly on the digital images. Linear and angular measurements were calculated electronically using the Dolphin version 9 software package. RESULTS: The average subject in the sample had a steeper mandibular plane, a more convex profile with a tendency for reduced chin protrusion, and a more protrusive dentition than the norms of the common analysis systems. In addition, the ranges of the skeletal and dentoalveolar parameters were larger than those reported in the above-mentioned norms. Gender differences were limited to maxillary and mandibular length and lower anterior facial height. CONCLUSION: The present findings indicate that Kuwaiti norms for incisor inclination and protrusion should be used as a reference when making the extraction decision in Kuwaiti orthodontic patients, and that the variation in skeletal relationships among subjects with satisfactory occlusal compensations is larger than previously documented, suggesting a need for establishing different norms for different skeletal patterns.

Adolescent↗

PubMed2006

Residual need for early orthodontic treatment and orthodontic treatment experience among 13- to 14-year-old school children in Kuwait.

OBJECTIVE: Our purpose was to determine the residual need for early orthodontic treatment and the parameters associated with orthodontic treatment experience in 13- to 14-year-old school children in Kuwait. SUBJECTS AND METHODS: A total of 788 boys and 795 girls, representing about 6.7% of the target population, were selected according to cluster sampling methods. Information on nationality, family income and orthodontic treatment experience was collected through subject and family interviews. The occlusal morphology was recorded in a well-lit classroom or from initial study models of subjects with orthodontic treatment experience. RESULTS: Only 6.7% of the 225 subjects with early treatment need, defined as overjet >or=6.5 mm, and functional posterior and anterior crossbite on 1 or more teeth, had treatment experience. Residual need for early treatment was present in 13.4% of the subjects. Only 26.8% of the subjects with treatment experience met our criteria for early treatment need. The odds of treatment experience were higher in the subjects attending private schools (p < 0.05), in those from families with an income of KWD >2,000 (USD 6,600; p < 0.01) and in subjects meeting the criteria for early treatment need (p < 0.01). CONCLUSIONS: About 15% of each birth cohort of school children in Kuwait need early orthodontic treatment. Less than 10% of those with a need have treatment experience at 13-14 years of age, and about 75% of those with treatment experience at that age do not need early treatment. The predictors for treatment experience at 13-14 years of age are private-school attendance, a high family income and need for early treatment.

Adolescent↗

PubMed2005

Apical root resorption 6 months after initiation of fixed orthodontic appliance therapy.

INTRODUCTION: Individual predisposition might be a major reason for the observed variation in apical orthodontic root resorption. If so, resorption might be expressed during the initial stages of orthodontic therapy in patients at risk. METHODS: To explore this hypothesis, we evaluated standardized, digitized periapical radiographs made before treatment (T1) and at a mean period of 6.4 months (SD 0.9) after placement of maxillary incisor brackets (T2) in 290 patients (age range, 10.1 to 57.1 years at T1). Anamnestic and treatment parameters were recorded according to a protocol, and maxillary incisor irregularity was measured on T1 study models. RESULTS: The mean average root resorption for 4 incisors was 0.53 mm (SD 0.47), whereas the sample mean of the most severely resorbed tooth per patient was 1.18 mm (SD 0.86). A total of 4.1% of the patients had an average resorption of 1.5 mm or more, and 15.5% had at least 1 tooth with 2.0 mm or more resorption. The maximum amount of resorption was 4.4 mm. Multivariate linear regression showed that deviated root form and increased T1-to-T2 time period were risk factors for apical root resorption of the central incisors; normal root form and wide roots were preventive factors, with an explained variance of 14%. Similarly, long roots, narrow roots, and increased T1-to-T2 time period were risk factors for resorption of the lateral incisors, whereas normal root form was a preventive factor, with an explained variance of 24%. Parameters associated with use of rectangular wire, presence of incisor irregularity, and history of trauma were not identified as risk factors. Use of elastics was not included in the regression analyses. CONCLUSIONS: Root resorption can begin in the early leveling stages of orthodontic treatment. About 4.1% of patients studied had an average resorption of 1.5 mm or more of the 4 maxillary incisors, and about 15.5% had 1 or more maxillary incisors with resorption of 2.0 mm or more from 3 to 9 months after initiation of fixed appliance therapy. Although teeth with long, narrow, and deviated roots are at increased risk of resorption during this early stage, the explained variance of these risk factors is less than 25%.

Adolescent↗

PubMed2005

Incisor trauma in an adolescent Arab population: prevalence, severity, and occlusal risk factors.

INTRODUCTION: Incisor trauma is a significant clinical problem in children and adolescents. The purposes of this study were to report on the prevalence and severity of incisor trauma in a large population-based sample of adolescent Kuwaiti residents in the early permanent dentition, to determine the ages of and reasons for the injuries, and to test for any effects of sex, incisor occlusion, and lip coverage on the prevalence of incisor trauma. METHODS: Presence and type of traumatic injury were scored according to the National Institute of Dental Research index in a population-based sample of 795 girls and 788 boys with a mean age of 13.24 years (SD 0.42). RESULTS: Trauma prevalence was higher (P < .001) in boys (19.3%) than in girls (9.7%), and in the maxilla (13.6%) than in the mandible (1.5%). Most (77.3 %) of the affected subjects had only 1 injured tooth, and most (83.7%) of the traumatized teeth were maxillary central incisors. A total of 90.3% of the injuries were unrepaired enamel or enamel/dentin fractures. The major reasons for the injuries were falls and blows indoors (48.4%) or outdoors (41.6%). Nearly two-thirds (63.0%) of the traumas occurred at age 10 years or later. Mean overjet (OJ) was larger (3.9 v 3.0 mm, P < .01), and lip incompetence more frequent (12.7% v 7.3%, P < .01) among the subjects with injured maxillary incisors than among those without. Logistic regression showed that the odds of maxillary incisor trauma were 2.8 times higher in subjects with OJ between 6.5 and 9.0 mm, and 3.7 times higher in subjects with OJ > or = 9.5 mm than in subjects with OJ < or = 3.5 mm. CONCLUSIONS: Multiple logistic regression showed that the risk of maxillary incisor trauma was about 2 times higher in boys than in girls, and that the risk increased by 13% for every millimeter of increase in OJ. Lip competence was not included in the model. No associations were found between occlusion and mandibular incisor trauma.

Accidental Falls↗

PubMed2005

Prediction of maxillary third molar impaction in adolescent orthodontic patients.

The purpose of this study was to identify risk factors for maxillary third molar impaction in adolescent orthodontic patients. Radiographs made before treatment (T1) and after treatment (T2) and at a minimum of 10 years postretention (T3) of 132 patients that allowed accurate diagnosis of impaction vs eruption of one or both maxillary third molars were evaluated. Although univariate logistic regression revealed that the decision to extract premolars reduced the risk of impaction by 76% (P < .01), this parameter was not included in the final prediction model at T1. Multiple logistic regression analyses revealed that third molar impaction could be predicted at T1 according to the size of the retromolar space and the amount of mesial molar movement that will occur during active appliance therapy, reducing the risk of impaction by 22% and 34% for every millimeter increase in distance, respectively (P < .01). At T2, multiple logistic regression revealed that the odds of impaction were more than 60 times higher (P < .01) if the third molar was angulated mesially as compared with less than 30 degrees distally relative to the occlusal plane and almost five times (P < .05) higher if the third molar was angulated more than 30 degrees distally as compared with less than 30 degrees distally. Similar analyses at T2 showed 29% reduced risk of impaction for every millimeter increase in retromolar space and 18% reduced risk for every degree increase in angle MP/SN (P < .01).

Adolescent↗

PubMed2005

Apical root resorption six and 12 months after initiation of fixed orthodontic appliance therapy.

The low explained variance of identified risk factors for apical root resorption in orthodontic patients suggests effects of parameters related to individual predisposition. Our purpose was to explore this hypothesis. We evaluated standardized periapical radiographs of the maxillary incisors made before treatment (T1) as well as at about six and 12 months after bracket placement (T2 and T3) of 247 patients aged 10.1 to 57.1 years at T1. The radiographs were converted to digital images, and commercially available software was used to correct for differences in projection. The results showed that 20.2%, 7.7%, and 5.3% of the patients had > or =1 tooth with >2.0, 3.0, and 4.0 mm resorption at T3, respectively. Pearson's correlation revealed an association between resorption from T1 to T2 and from T2 to T3 (P < .01). The risk of > or =1 tooth with >1.0 mm resorption from T2 to T3 was 3.8 times higher (95% CI 2.4-6.0) in patients with > or =1 tooth with >1.0 mm from T1 to T2 than in those without. Also, resorption was more pronounced (P < .001) from T2 to T3 in patients with > or =1 tooth with >1.0 mm and >2.0 resorption from T1 to T2 than in those without. The explained variance of identified risk factors was <10%. Orthodontic patients with detectable root resorption during the first six months of active treatment are more likely to experience resorption in the following six-month period than those without.

Adolescent↗

PubMed2003

Prevalence of third molar impaction in orthodontic patients treated nonextraction and with extraction of 4 premolars.

The purposes of this study were to confirm that premolar extraction treatment is associated with mesial movement of the molars concomitant with an increase in the eruption space for the third molars and to test the hypothesis that such treatment reduces the frequency of third molar impaction. Lateral cephalograms, panoramic or periapical radiographs, and study models made before (T1) and after (T2) treatment and a minimum of 10 years postretention (T3) of 157 patients were selected from the postretention sample at the Department of Orthodontics of the University of Washington, Seattle. Treatment for 105 patients included the extraction of 4 premolars; the other 53 were treated nonextraction. These patients represented all the extraction and nonextraction patients in the sample who had at least 1 third molar at T1 or T2 and who showed evidence of full eruption or closure of the root apex at T2 or T3. Student t tests showed higher scores for third molar impaction (P <.01), less mesial movement of the molars from T1 to T2 (P <.01), and smaller retromolar space at T2 (P <.001) in both arches of the nonex patients than in the ex patients. Similarly, molar movement was more mesial from T1 to T2 in the maxilla (P <.01) and in the mandible (P <.05), and the retromolar space was larger in both arches (P <.001) of the patients with eruption than in those with impaction of the third molars. Our results suggest that premolar extraction therapy reduces the frequency of third molar impaction because of increased eruption space concomitant with mesial movement of the molars during space closure.

Adolescent↗

PubMedDate not supplied

Prevalence and severity of malocclusion in adolescent Kuwaitis.

OBJECTIVES: Our aim was to evaluate prevalence and severity of malocclusion in an adolescent Kuwaiti population. SUBJECTS AND METHODS: Using a stratified cluster sampling method and excluding non-Kuwaitis, subjects with mesial migration and/or loss of first molars, and subjects with orthodontic treatment experience without availability of initial study models, we examined 1,299 Kuwaitis (674 boys and 625 girls) of mean age 13.2 +/- 0.4 years in a regular well lit classroom. We scored molar and canine relationship, overjet, overbite, anterior and posterior cross bite as well as spacing and irregularity of the incisors using gloves, mirrors, rulers, and spatulas. RESULTS: Fourteen, 15, and 71% met the criteria for almost ideal, mild, and moderate to severe malocclusion, respectively. Of the 86% with malocclusion, occurrence of class 1, half step class 2, full step class 2, half step class 3, and full step class 3 was 57.8, 24.9, 6.3, 8.8, and 2.2% for the first molars, and 36.1, 50.0, 6.2, 5.4, and 2.3% for the canines, respectively. Incisor malalignment was the most prevalent malocclusion trait (73.2%). Overjet > or = 9.5 mm occurred in less than 1.5%, open bite in less than 3.5%, deep bite with gingival contact in less than 2.0%, complete posterior cross bite in less than 1.5%, and complete anterior crossbite in less than 2.0%. Median diastema was present in about 2/3 of the cases with maxillary anterior spacing as opposed to only about 1/3 of those with mandibular spacing. CONCLUSION: Our findings suggest that more than 70% of young adolescent Kuwaitis have moderate to severe malocclusion, with incisor malalignment as the most prevalent malocclusion trait.

Adolescent↗