A Radiographic Evaluation of Missing of Permanent First Molars in a Group of Iranian Children and Adults: A Retrospective Study.

The missing of permanent first molars influences the occlusal status and dental health. The purpose of this study was to determine the prevalence of missing first molar teeth in a selected population of Shiraz, Iran. Methods. A total of 2206 panoramic views of patients aged from 7 to 75 years old were inspected for missing of permanent first molars. Patients were categorized into five age groups: from 7 to 15, 16 to 30, 31 to 45, 46 to 60, and more than 60 years old. Data were categorized according to sex, age, and number of lost teeth using SPSS software. Results. No first molar was missing in 59.9% of the cases, 17.05% had lost one, 10.4% had lost two, 7.2% had lost three, and 5% were missing all four of their permanent first molars. The mandibular first molar was the most commonly lost tooth, and the left side in both jaws was more affected than the right side. There was a positive relation between age and missing first molar. Conclusions. A missing first molar is a common finding in southern Iran population. Due to the important role of permanent first molars in occlusion, more education and dental care is recommended to preserve these teeth.

The prevalence of pathologic tooth migration with respect to the severity of periodontitis.

AIM: Pathologic tooth migration (PTM) has been defined as tooth displacement that occurs when the balance among the factors that maintain physiologic tooth position is disturbed by periodontal disease. The aim of this cross-sectional epidemiological study was to determine the prevalence of pathologic tooth migration among patients with periodontitis. MATERIALS AND METHODS: Recorded documents of 370 patients (72.4% females, 27.6% males) within the age range of 17 to 70 years (mean 37.77 ± 11.46) were studied. Statistical analysis was carried out using t-test and Chi-square test. RESULTS: Pathologic migration prevalence was 11.4% (35/314 patients), however, there was no pathologic migration in patients with mild chronic periodontitis. The Chi-square test showed that there was no statistically significant difference between males and females. CONCLUSIONS: The results of this study confirm that pathologic tooth migration is relatively common among periodontal patients and its prevalence is increased by the severity of periodontal disease.