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In recent years, the spatial lattice data has been a motivating issue for researches. Modeling of binary variables observed at locations on a spatial lattice has been sufficiently investigated and the autologistic model is a popular tool for analyzing these data. But, there are many situations where binary responses are clustered in several uncorrelated lattices, and only a few studies were found to investigate the modeling of binary data distributed in such spatial structure. Besides, due to spatial dependency in data exact likelihood analyses is not possible. Bayesian inference, for the autologistic function due to intractability of its normalizing-constant, often has limitations and difficulties. In this study, spatially correlated binary data clustered in uncorrelated lattices are modeled via autologistic regression and IBF (inverse Bayes formulas) sampler with help of introducing latent variables, is extended for posterior analysis and parameter estimation. The proposed methodology is illustrated using simulated and real observations.

Introduction Ameloblastic fibro-odontoma (AFO) is defined as a benign odontogenic tumor with slow growing behavior. Its prevalence is rare. AFO is characterized by histologic features of ameloblastic fibroma (AF) with the formation of enamel and dentine. Case presentation This is a case report of AFO accompanied with a number of impacted deciduous teeth and its management in a 4-year old boy. Examination of oral cavity revealed an extensive swelling from midline to left deciduous maxillary first molar, covered with normal mucosa. Radiographic examination showed a well-defined mixed radiolucent-radiopaque lesion that extended horizontally from midline to mesial border of the left maxillary primary first molar and vertically from alveolar crest to the floor of nose. The differential diagnosis was odontoma (ameloblastic fibro-odontoma, complex odontoma). Surgical enucleation and curettage was performed under general anesthesia. Histopathologic sections show bone trabeculae in marrow spaces. There was myxoid matrix in some spaces which contained odontogenic epithelial cells. These findings led to diagnosis of AFO. No sign of recurrence has been observed during the 12-month follow-up period. Conclusion Although AFO is a rare tumor, it is more prevalent in children's jaw. Conservative surgical treatment allowed the normal development of teeth.

The autologistic model, first introduced by Besag, is a popular tool for analyzing binary data in spatial lattices. However, no investigation was found to consider modeling of binary data clustered in uncorrelated lattices. Owing to spatial dependency of responses, the exact likelihood estimation of parameters is not possible. For circumventing this difficulty, many studies have been designed to approximate the likelihood and the related partition function of the model. So, the traditional and Bayesian estimation methods based on the likelihood function are often time-consuming and require heavy computations and recursive techniques. Some investigators have introduced and implemented data augmentation and latent variable model to reduce computational complications in parameter estimation. In this work, the spatially correlated binary data distributed in uncorrelated lattices were modeled using autologistic regression, a Bayesian inference was developed with contribution of data augmentation and the propos...

Objectives The main objective of this study was modelling experienced caries of deciduous teeth in 3–5 years old children treated in Children's Department of Tehran University of Medical Sciences, Iran, using the spatial autologistic regression. The other objective was identifying a risk pattern of decayed dents of these children. Materials and methods The study group consisted of 400 children (3–5 years old). Two groups of postgraduate and under graduate dentistry students under consideration and approval of the professors of dentistry from the Tehran University of Medical Sciences diagnosed and categorised the caries statuses of deciduous dents of the children. The caries statuses were considered as spatially correlated binary data. The appropriate model was autologistic regression. Results The fitted autologistic model showed that caries in the three nearest neighbours of a tooth, which includes the two adjacent and the one vertically opponent teeth, had significant effect on its caries. The computed risks based on the fitted model revealed a definite-spatial pattern of caries events. Conclusions Every decayed deciduous tooth in the mouth of a preschool child threatens the three nearest teeth. The risk pattern of caries in each quarter of the teeth lattice of children from incisors to molars has an ascending rate. The dents in maxilla and posterior locations have higher risks of caries than in mandible and anterior locations. These findings are valuable in preventive health care and therapeutic approaches in dentistry of children.

Childhood nutrition is known to have a considerable impact on children's health. Protein and fat are the two most important macronutrients with high impact on children's growth and energy provision. The aim of the present study is the assessment of children's nutrition based on energy, protein and fat intake with respect to their anthropometric and oral health. A total of 788 7-years-old primary school children selected via a cluster sampling in Tehran City, Iran. The general information about children has been asked from their mothers. Anthropometric measurements including weight and height measurements are also taken for each child. Finally the routine standard tooth check up was performed to get the dmft index. The chi-square test, Mann-Whitney U-test and Kruskal-Wallis were used for detecting statistical associations. Results showed that there is not a significant association between macronutrient intakes and anthropometric indices; however it was found that children who get saturated fat less than 75% recommended have higher dmft. The same results were found for energy, protein and total fat, but none of which were statistically significant. This study highlights the important role of saturated fatty acids in prevention of dental carries.