The Cameriere, Haavikko, Demirjian, and Willems methods for the assessment of dental age in Croatian children.

AIM: This study aimed to evaluate the accuracy and precision of the Cameriere European formula, Demirjian, Haavikko, and Willems methods for estimating dental age in a sample of children with permanent dentition in Croatia. MATERIAL AND METHODS: The study consisted of a sample of 1576 panoramic radiographs; a sub-sample of 84 OPGs, in which all first seven mandibular teeth were maturated, was excluded from the study. A final sample of 1492 (704 males and 788 females) aged 6.0 to 13.9 years was evaluated. Seven mandibular teeth from the left side of the mandible were analyzed, and dental age (DA) was determined by the Cameriere European formula, Demirjian method from 1976, Haavikko, and Willems methods and compared to chronological age (CA). In addition, the mean age difference (DA-CA), the mean absolute error (MAE) between dental and chronological age, the percentage of the individuals of dental age within ± 0.25 to ± 2 years of chronological age, and intra-observer and inter-observer statistics were calculated. RESULTS: The Cameriere European formula estimated the best dental age compared to the chronological age; the mean underestimation was - 0.4 years for both sexes, Haavikko underestimated by - 0.17 years, while Demirjian and Willems overestimated by 1.02 years and 0.48 years, respectively. The most significant difference showed the Demirjian method in 11-year-old and 12-year-old females. The MAE were 0.50 years, 1.01 years, 0.61 years, and 0.78 years in males and 0.51 years, 1.18 years, 0.61 years, and 0.70 years in females for the Cameriere European formula, Haavikko, Willems, and Demirjian methods, respectively. Furthermore, the Cameriere European formula showed the highest proportions of individuals with DA within ± 0.5 year difference of the CA, 61.5% in males and 59.6% in females. In addition, the Cameriere method showed the best intra-observer and inter-observer agreements. CONCLUSIONS: Although the Demirjian method was used previously in Croatian children for legal, medical, and clinical purposes, the Cameriere European formula, Haavikko, and Willems were more accurate in the tested sample. According to our findings, the Cameriere European formula showed the best accuracy and precision in dental age assessment in Croatian children following Haavikko, and we recommend it as the method of the first choice in forensic and clinical analyses.

Assessment of the relationship between labial gingival thickness and the underlying bone thickness in maxillary anterior teeth by two digital techniques.

This study aimed to noninvasively assess the relationship between the labial gingival thickness (GT) and the underlying bone thickness (BT) of maxillary anterior teeth by two digital techniques. A total of 30 periodontally healthy participants with 172 maxillary anterior teeth were enrolled. GT and BT were measured at 2, 4 and 6 mm apical to the cemento-enamel junction (CEJ) by two digital techniques: M1-cone-beam computed tomography (CBCT) and M2-digital intraoral scanning (DIS) combined with CBCT. The Pearson's correlation coefficient was calculated to determine the correlation between GT and BT. A significant negative correlation was identified between GT and BT at 2 mm apical to the CEJ for central incisors (CI), lateral incisors (LI), and canines (CA) both by M1 and M2, while a weak negative correlation at 4 mm apical to the CEJ was observed by M1 for CA. No significant correlation was found at other sites by both M1 and M2. The labial BT was < 1 mm in most cases (85% of CI; 97% of LI; and 90% of CA). Within the limitation of this study, it was concluded that GT and BT seemed to be negatively correlated at 2 mm apical to the CEJ. Therefore, caution is warranted when implant restoration at the esthetic area of the anterior teeth.

The effectiveness of a 3D virtual tooth identification test as an assessment tool for a dental anatomy course.

INTRODUCTION: There has been a recent demand in dental education for distance learning and the use of virtual assessment tools that can leverage technology to potentially replace physical testing facilities. However, virtual tools that evaluate student learning should be validated prior to adoption. The aim of this study was to investigate the effectiveness, efficiency and user satisfaction of a 3D tooth identification test for a dental anatomy course that can be given remotely. MATERIALS AND METHODS: First-year dental students (n = 41) enrolled in a dental anatomy course took both traditional in-person practical and virtual 3D tooth identification tests consisting of 25 test items. The test scores, average test durations, faculty time commitment and user perception were collected and analysed. Pearson product-moment correlation coefficients (p < .05) were determined for the criterion measures including real tooth identification test scores, comprehensive written examination and overall grade for the course. RESULTS: The average number of correct answers for the real and 3D virtual tooth identification examination was 21.3 ± 2.65 and 20.7 ± 2.56, respectively. The average test duration for the real and 3D virtual tooth identification test was 25:00 and 21:16 min, respectively. There was a positive correlation (p < .05) of the 3D virtual tooth identification test with the real tooth identification test (0.368), comprehensive written examination (0.334) and the overall course grade (0.646). The total faculty time commitment for the real and 3D virtual tooth identification test was 96 and 65 min, respectively. The students cited difficulty in manipulating the 3D models. CONCLUSION: This study presents evidence that the 3D virtual tooth identification test can be used to assess dental students' understanding of dental anatomy effectively and efficiently.

Assessment of the accuracy of 3D printed teeth by various 3D printers in forensic odontology.

Additive manufacturing technology has benefited many sectors, and its use in forensic sciences has opened up a variety of new opportunities for analysing and exhibiting forensic materials. However, to perform analytical procedures on 3D printed bones and teeth in forensic odontology, the metric and morphological precision of the printed replicas must first be validated. To address this, the present study was undertaken using 12 extracted human teeth that were 3D printed using five different techniques. Manual measurements and a digital mesh comparison were used to evaluate the metric precision of all samples. The findings showed that the printed replicas were accurate to within 0.5 mm of the actual teeth. It was suggested that Digital Light Processing (DLP) prints be used for potential forensic odontology applications based on measurements, digital comparison, and ease of use.

Assessment of maturation indicators in individuals with different skeletal malocclusion.

PURPOSE: The aim of this study was to comparatively evaluate hand-wrist bones, cervical vertebrae and tooth development stages according to skeletal classification. METHODS: The orthodontic initial records of 297 patients were used and separated into three groups according to the skeletal malocclusion. Three groups including 99 people each were sampled representing malocclusions with Angle classes I, II and III, respectively. The panoramic, cephalometric and hand-wrist radiographs of all patients included in this study were used to compare dental and skeletal maturation indicators. Calcification of teeth was rated according to the system of Demirjian. To evaluate the stage of skeletal maturation hand-wrist radiographs were analyzed according to the Grave and Brown method. Also, Hassel and the Farman method was used to classifying vertebral developmental stages. Spearman rank correlation tests, as well as Fisher exact χ2 tests with r×c tables, were used for the comparison of categorical variables. RESULTS: Hand-wrist, vertebral and dental development stages showed a statistically significant relationship (p < 0.01) for both genders and in all malocclusions. The association between the different maturation indicators used in this study and the type of malocclusion was also statistically significant for both genders. It was observed that the peak period of skeletal maturation according to the hand-wrist radiograph findings correlated with the cervical vertebrae stage C3 in girls (63.2%) and C2-C3 in boys (43.5-43.5%). The weakest correlation was seen between the dental development stages and the skeletal developmental stages in the class II group (r = 0.443-0.220 [girls]; r = 0.604-0.410 [boys]). CONCLUSION: The use of the dental development stage as a reliable indicator of maturation was limited. According to the Demirjian method, the calcification stage of the second molar might indicate that the individual is in the pubertal peak period.

Dental age and skeletal maturity assessment in patients with cerebral palsy.

The aims of this study were to calculate the estimated dental age and the degree of skeletal maturity in patients with cerebral palsy and control patients (i.e., without a diagnosis of cerebral palsy) and to compare the findings with the chronological age of patients in both study groups. In this cross-sectional study, the European formula and the Willems method were used to estimate the dental age of 52 patients with cerebral palsy and 104 control patients, all aged between 7 and 15 years. For all patients, their estimated dental age was compared with their chronological age. The degree of skeletal maturity of 35 patients with cerebral palsy and 104 control patients was estimated according to Baccetti's method. There was no statistically significant difference in the deviation of the estimated dental age from the chronological age between patients with cerebral palsy and control patients when the European formula or the Willems method was applied. No difference was found in the frequency of Baccetti's stages between patients with cerebral palsy and control patients in the same age category, for both sexes. To estimate dental age in patients with cerebral palsy, the European formula is preferable for orthodontic purposes and the Willems method is preferable for forensic purposes. Using Baccetti's method it was not possible to detect potential differences in skeletal maturity between patients with cerebral palsy and controls.

Dental and Skeletal Imaging in Forensic Age Estimation: Disparities in Current Approaches and the Continuing Search for Optimization.

Medical imaging for forensic age estimation in living adolescents and young adults continues to be controversial and a subject of discussion. Because age estimation based on medical imaging is well studied, it is the current gold standard. However, large disparities exist between the centers conducting age estimation, both between and within countries. This review provides an overview of the most common approaches applied in Europe, with case examples illustrating the differences in imaging modalities, in staging of development, and in statistical processing of the age data. Additionally, the review looks toward the future because several European research groups have intensified studies on age estimation, exploring four strategies for optimization: (1) increasing sample sizes of the reference populations, (2) combining single-site information into multifactorial information, (3) avoiding ionizing radiation, and (4) conducting a fully automated analysis.

An accurate and efficient method for occlusal tooth wear assessment using 3D digital dental models.

Tooth or material wear in a dentition is a common finding that requires timely diagnosis for management and prevention of further loss or associated esthetic or functional impairment. Various qualitative and quantitative methods have been suggested to measure tooth or material wear, but they present with limitations, such as imprecision, subjectivity, or high complexity. Here we developed and assessed an efficient 3D superimposition method to accurately measure occlusal tooth wear on 3D digital dental models. For this purpose, teeth on plaster casts were manually grinded on their occlusal surfaces to simulate various degrees of tooth wear. The casts were scanned using a surface scanner. Grinded tooth crowns (T1) were segmented and compared to the original crowns (T0) using five 3D surface superimposition techniques and a gold standard technique (GS). GS measurements were obtained by using intact adjacent structures as superimposition references. The technique of choice (complete crown with 30% estimated overlap of meshes) showed the best reproducibility (maximum difference < 0.050 mm3) and excellent agreement with the GS technique (median difference: 0.032 mm3). The suggested 3D superimposition method offers a highly efficient and accurate tool for tooth wear assessment, which could be applicable to clinical conditions.

CBCT assessment of bone thickness in maxillary and mandibular teeth: an anatomic study.

OBJECTIVE: The site of the sinus tract depends on the rate of resistance against abscess exudate drainage, bone morphology, and distance from the root apex to the outer cortical bone. To assess apical bone thickness in buccal and palatal/lingual aspects of maxillary and mandibular teeth, using a high-resolution cone-beam computed tomography (CBCT) system. METHODOLOGY: In total, 422 CBCT examinations were included in the study, resulting in a sample of 1400 teeth. The scans were acquired by PreXion 3D, with a high-resolution protocol. The bone thickness was taken as the distance between the center of the apical foramen and the buccal and lingual/palatal cortical bone. The quantitative variables were expressed as mean values±standard deviation. The independent samples were analyzed using the t-test or the Mann-Whitney test (p<0.05). RESULTS: The lowest mean value of bone thickness was observed in the buccal cortical bone of the upper canines (1.49 mm±0.86) and in the upper central incisors (1.59 mm±0.67). In premolar teeth, the lowest values were found in the buccal cortical bone of upper first premolars (1.13 mm±0.68). In the posterior teeth, the lowest values were found in the buccal cortical bone of upper first molars (1.98 mm±1.33). In the lower second molar region, the buccal cortical bone (8.36 mm±1.84) was thicker than the lingual cortical bone (2.95 mm±1.16) (p<0.05). CONCLUSIONS: The lowest mean values of bone thickness are in the buccal cortical bone of the maxillary teeth. In the mandible, bone thickness is thinner in the buccal bone around the anterior and premolar teeth, and in the lingual aspect of mandibular molars. All these anatomic characteristics could make the occurrence of the sinus tract more susceptible in these specific regions of the maxillary and mandibular alveolar bone.

Electromechanical impedance measurements for bone health monitoring through teeth used as probes of a Piezo-device.

Bone is a dynamic biological tissue that acts as the primary rigid support of the body. Several systemic factors are responsible for pathologies that negatively affect its structural attributes. Although the bone is in continuous renewal by osteogenesis, metabolic diseases are the most common affectations that alter its natural equilibrium. Different techniques based on ionizing radiation are used for the bone diagnosis restrictively. However, if these are not used adequately, the application could present risks for human health. In this paper, it is proposed and explored a new technique to apply an early-stage diagnosis of bone variations. The technique evaluates bone structural conditions from the teeth (used as probes) by applying a structural health monitoring (SHM) methodology. An experimental procedure is described to identify the stiffness variations produced by mechanical drillings done in prepared bone samples. The identification is carried out applying the electromechanical impedance technique (EMI) through a piezo-actuated device in the frequency spectrum 5-20kHz. Three bone samples with incorporated teeth (three teeth, two teeth, and one tooth) were prepared to emulate a mandibular portion of alveolar bone-PDL (periodontal ligament)-tooth system. Piezo-device was attached to the crown of the tooth with an orthodontic bracket allowing the teeth to act as probes. The electrical resistance measurements were computed with an electrical decoupling approach that improved the detection of the drillings; it was due to the increment of the sensitivity of the signals. The results showed that the bone mass reduction is correlated with statistical indices obtained in specific frequency intervals of the electrical resistance. This work suggests the possibility of a future application addressed to a bone diagnosis in a non-invasive way.

CBCT assessment of bone thickness in maxillary and mandibular teeth: an anatomic study

Abstract The site of the sinus tract depends on the rate of resistance against abscess exudate drainage, bone morphology, and distance from the root apex to the outer cortical bone. Objective To assess apical bone thickness in buccal and palatal/lingual aspects of maxillary and mandibular teeth, using a high-resolution cone-beam computed tomography (CBCT) system. Methodology In total, 422 CBCT examinations were included in the study, resulting in a sample of 1400 teeth. The scans were acquired by PreXion 3D, with a high-resolution protocol. The bone thickness was taken as the distance between the center of the apical foramen and the buccal and lingual/palatal cortical bone. The quantitative variables were expressed as mean values±standard deviation. The independent samples were analyzed using the t-test or the Mann-Whitney test (p<0.05). Results The lowest mean value of bone thickness was observed in the buccal cortical bone of the upper canines (1.49 mm±0.86) and in the upper central incisors (1.59 mm±0.67). In premolar teeth, the lowest values were found in the buccal cortical bone of upper first premolars (1.13 mm±0.68). In the posterior teeth, the lowest values were found in the buccal cortical bone of upper first molars (1.98 mm±1.33). In the lower second molar region, the buccal cortical bone (8.36 mm±1.84) was thicker than the lingual cortical bone (2.95 mm±1.16) (p<0.05). Conclusions The lowest mean values of bone thickness are in the buccal cortical bone of the maxillary teeth. In the mandible, bone thickness is thinner in the buccal bone around the anterior and premolar teeth, and in the lingual aspect of mandibular molars. All these anatomic characteristics could make the occurrence of the sinus tract more susceptible in these specific regions of the maxillary and mandibular alveolar bone.

Cone-beam computed tomography assessment of Schneiderian membranes: Non-infected and infected membranes, and membrane resolution following tooth extraction: A retrospective clinical trial.

BACKGROUND: Cone-beam computed tomography (CBCT) presurgical assessment on the maxillary sinus can reduce the possibility of Schneiderian membrane perforation. This study examined Schneiderian membrane thickness (SMT) and its relationship with neighboring hard tissues for patients with and without membrane thickening. For patients with sinus infections, we evaluated dimensional changes of the SMT post-extraction relative to pre-extraction SMT and residual bone height (RBH). METHODS: CBCT images from 93 patients needing single-tooth implant reconstruction without (n = 83) and with (n = 14) odontogenic infected maxillary sinuses were assessed. SMT, RBH, and lateral wall thickness (LWT) were measured. Causes of extraction, RBH in the infection site, and retrospective post-extraction record of SMT were recorded for the thickened SMT group. RESULTS: Mean SMT for normal SMT group was 1.13 ± 0.43 mm, RBH was 6.26 ± 2.38 mm; upper and lower LWT was 1.85 ± 0.95 mm, and 3.07 ± 2.26 mm, respectively. RBH and LWT had no significant relationships with SMT. For thickened SMT group, mean values for SMT and RBH prior to extraction were 4.53 ± 2.46 mm and 1.97 ± 1.43 mm, respectively. Pre-extraction SMT had a moderately negative correlation with pre-extraction RBH. SMT resolution in thickened SMT group was observed by 2.80 ± 1.37 months post-extraction; post-extraction SMT was not significantly different from normal SMT group (p = .187). CONCLUSIONS: Within the limitation of the sample size, thickened SMT induced by odontogenic infection subsides about 3 months following tooth extraction, and further sinus lifting implant surgery may be considered.

Dental age assessment of 3-15-year-old Saudi children and adolescents using Demirjian's method-A radiographic study.

Dental age assessment plays a pivotal role in clinical practice, demographic studies, forensics, and courts of law but is affected by ethnic and geographic variations. The aim was to determine the population-specific weighted scores needed when dental age is estimated using Demirjian's method for Saudi children and adolescents between the ages of 3 and 15 years. Design: A total of 298 panoramic radiographs were collected from Saudi Arabia. Dental age was assessed using Demirjian's method (1973). Chronological age was determined from the date of birth and the date on which the panoramic radiograph was taken for each individual. Between 3- and 15-years age group, the Saudi boys had an estimated age of 9.07 ± 1.96 years and chronological age of 8.49 ± 2.30 years. The Saudi girls had an estimated age of 9.22 ± 1.93 years and chronological age of 8.78 ± 2.32 years. With Demirjian's method, the Saudi boys were 0.57 ± 1.48 years, and girls were 0.44 ± 1.66 years ahead of their chronological ages (p < .05). New population-specific weighted scores were developed to convert dental age according to Demirjian's method into estimated ages in the contemporary Saudi Arabian population. This study can be used for further research and comparisons with other population groups, regions or communities.

Mandibular radiomorphometric assessment of bone mineral density in survivors of pediatric hematopoietic stem-cell transplantation.

OBJECTIVE: Hematopoietic stem-cell transplantation (HSCT) childhood survivors of hematologic malignancies are prone to develop late osteopenia and osteoporosis. The purpose of this retrospective study was to quantitatively and qualitatively assess bone mineral density (BMD) in HSCT childhood survivors and to compare the effectiveness of both qualitative and quantitative assessment methods. METHODS: DESIGN BMD assessment using panoramic radiographs of childhood HSCT survivors aged 3.69-18.88 years using two radiomorphometric indexes. Case-control double-blinded comparison of panoramic radiographic images from childhood HSCT survivors and age- and sex-matched healthy controls. Quantitative assessment was performed by measuring the cortical bone width bilaterally at the mental foramen level. Qualitative assessment was performed using the mandibular cortical index bilaterally on all panoramic images. RESULTS: Radiographs were taken 6.59-83.95 months after bone marrow transplantation [median±SD=25.92±24.9 months]. Fifty-two panoramic radiographic images were analyzed: 21 from HSCT survivors and 31 from healthy controls aged 3.69-25.1 years [mean±SD=11.89±5.28 years]. The mandibular cortical bone width was 17% smaller in childhood HSCT survivors than in healthy controls (case group: 2.420, control group: 3.307; p=0.00617). Qualitative analysis revealed an increased frequency of severe mandibular cortical erosion in childhood HSCT survivors, although no significant difference was observed (case group: 1.540, control group: 1.490; p=0.32). The interobserver agreement was 85% (Kappa index). CONCLUSIONS: HSCT childhood survivors exhibit quantitative and qualitative mandibular bone impairments. Further studies are needed to establish an association between mandibular cortical bone impairment and osteoporosis.

Halve the dose while maintaining image quality in paediatric Cone Beam CT.

Cone beam CT (CBCT) for dentomaxillofacial paediatric assessment has been widely used despite the uncertainties of the risks of the low-dose radiation exposures. The aim of this work was to investigate the clinical performance of different CBCT acquisition protocols towards the optimization of paediatric exposures. Custom-made anthropomorphic phantoms were scanned using a CBCT unit in six protocols. CT slices were blinded, randomized and presented to three observers, who scored the image quality using a 4-point scale along with their level of confidence. Sharpness level was also measured using a test object containing an air/PMMA e,dge. The effective dose was calculated by means of a customized Monte Carlo (MC) framework using previously validated paediatric voxels models. The results have shown that the protocols set with smaller voxel size (180 µm), even when decreasing exposure parameters (kVp and mAs), showed high image quality scores and increased sharpness. The MC analysis showed a gradual decrease in effective dose when exposures parameters were reduced, with an emphasis on an average reduction of 45% for the protocol that combined 70 kVp, 16 mAs and 180 µm voxel size. In contrast, both "ultra-low dose" protocols that combined a larger voxel size (400 µm) with lower mAs (7.4 mAs) demonstrated the lowest scores with high levels of confidence unsuitable for an anatomical approach. In conclusion, a significant decrease in the effective dose can be achieved while maintaining the image quality required for paediatric CBCT.

Role of Imaging in the Assessment of Age Estimation.

Age assessment by skeletal age estimation of unknown individuals is of paramount importance in forensic science, both for assessing imputability (if the author of a crime is old enough to be tried and judged), both in case of unaccompanied minors, or whether refugees and asylum seekers are adults or juveniles, which implies different legal issues and procedures. The aim of this article is to review the age estimation methods used in forensic practice.

Differential Identification of Three Young Housefire Victims: Methods when Age Assessment Fails.

Multiple fatality incidents involving more than one child of statistically same age (including twins) can be challenging from an identification standpoint. This case details an urban fire, in which four children perished. Age assessment on three of the victims utilizing maturity staging described by Moorrees, Fanning, and Hunt yielded insignificant results. However, a plot of the MFH data shows the difference between two identical twins and a third child. The twins share a similar growth pattern, whereas the other was different. Based on this graphical interpretation, the nontwin victim was positively identified through exclusion. These results were verified through statistical testing. This case demonstrates a method to repurpose age assessment data to graphically distinguish between child victims. Further, it is shown that radiographic and clinical presentation in childhood identical twins can elicit genetic versus acquired similarities and differences, which can be used for identification of individuals and exclusion of others.

Development and Assessment of a Three-Dimensional Tooth Morphology Quiz for Dental Students.

Tooth morphology has a pivotal role in the dental curriculum and provides one of the important foundations of clinical practice. To supplement tooth morphology teaching a three-dimensional (3D) quiz application (app) was developed. The 3D resource enables students to study tooth morphology actively by selecting teeth from an interactive quiz, modify their viewpoint and level of zoom. Additionally, students are able to rotate the tooth to obtain a 3D spatial understanding of the different surfaces of the tooth. A cross-over study was designed to allow comparison of students' results after studying with the new application or traditionally with extracted/model teeth. Data show that the app provides an efficient learning tool and that students' scores improve with usage (18% increase over three weeks, P < 0.001). Data also show that student assessment scores were correlated with scores obtained while using the app but were not influenced by the teaching modality initially accessed (r2  = 0.175, P < 0.01). Comparison of the 2016 and 2017 class performance shows that the class that had access to the app performed significantly better on their final tooth morphology assessment (68.0% ±15.0 vs. 75.3% ±13.4, P < 0.01). Furthermore, students reported that the 3D application was intuitive, provided useful feedback, presented the key features of the teeth, and assisted in learning tooth morphology. The 3D tooth morphology app thus provides students with a useful adjunct teaching tool for learning dental anatomy. Anat Sci Educ 00: 000-000. © 2018 American Association of Anatomists.

Mandibular radiomorphometric assessment of bone mineral density in survivors of pediatric hematopoietic stem-cell transplantation

OBJECTIVE: Hematopoietic stem-cell transplantation (HSCT) childhood survivors of hematologic malignancies are prone to develop late osteopenia and osteoporosis. The purpose of this retrospective study was to quantitatively and qualitatively assess bone mineral density (BMD) in HSCT childhood survivors and to compare the effectiveness of both qualitative and quantitative assessment methods. METHODS: DESIGN BMD assessment using panoramic radiographs of childhood HSCT survivors aged 3.69-18.88 years using two radiomorphometric indexes. Case-control double-blinded comparison of panoramic radiographic images from childhood HSCT survivors and age- and sex-matched healthy controls. Quantitative assessment was performed by measuring the cortical bone width bilaterally at the mental foramen level. Qualitative assessment was performed using the mandibular cortical index bilaterally on all panoramic images. RESULTS: Radiographs were taken 6.59-83.95 months after bone marrow transplantation [median±SD=25.92±24.9 months]. Fifty-two panoramic radiographic images were analyzed: 21 from HSCT survivors and 31 from healthy controls aged 3.69-25.1 years [mean±SD=11.89±5.28 years]. The mandibular cortical bone width was 17% smaller in childhood HSCT survivors than in healthy controls (case group: 2.420, control group: 3.307; p=0.00617). Qualitative analysis revealed an increased frequency of severe mandibular cortical erosion in childhood HSCT survivors, although no significant difference was observed (case group: 1.540, control group: 1.490; p=0.32). The interobserver agreement was 85% (Kappa index). CONCLUSIONS: HSCT childhood survivors exhibit quantitative and qualitative mandibular bone impairments. Further studies are needed to establish an association between mandibular cortical bone impairment and osteoporosis.

Assessment of dental maturation on orthopantomograms among children with various dental malocclusions at a tertiary care hospital.

OBJECTIVE: To determine and compare the median dental age among males and females and in subjects with dental Class I, II and III malocclusions. METHODS: The retrospective study was conducted at Aga Khan University Hospital and comprised dental records of patients from July to December 2016 who were aged 9-16 years and had complete dentition excluding third molars. The sample was divided according to dental malocclusion which was further categorised according to chronological age groups. SPSS 21 was used for data analysis. RESULTS: Of the 270 sbjects whose radiographs were studied, 135(50%) each were males and females. Children aged 11-12 years showed a statistically significant difference (p=0.03) in the median dental age among genders. There was a strong positive correlation in the dental and chronological ages in the males (p<0.001) and females (p<0.001) sample. Median time of eruption of mandibular second permanent molar in different malocclusions was 11 years and 2 months. CONCLUSIONS: There was a strong positive correlation between chronological and dental ages for males and females. Females subjects were dentally advanced compared to the male subjects aged 11-12 years. ..