جستجوی مقالات مرتبط با کلیدواژه "permanent molar" در نشریات گروه "پزشکی"

Restoration of freshly erupted permanent first molars with extensive caries is a challenge in pediatric dentistry. This study aimed to compare the fracture resistance of permanent molars with undermined walls restored with amalgam and composite resin along with cusp reduction, reinforcement of the walls with glass ionomer (GI) or no further intervention. This experimental in-vitro study evaluated 72 freshly extracted sound human third molars with almost equal dimensions. After cavity preparation, the teeth were then randomly divided into three groups. In group 1, the undermined area was reinforced with light-cure GI. Group 2 received a 2 mm cuspal cap, and group 3 received no intervention. Half of the teeth in each group were restored with composite resin and the other half with amalgam. The teeth then underwent thermocycling and their fracture resistance was measured by a universal testing machine. Data were analyzed using two-way ANOVA. No significant difference was noted in fracture resistance among three procedures in teeth restored with composite (P=0.589). However, this difference was significant in teeth restored with amalgam (P=0.001). The current results indicated when esthetics is not a priority, applying amalgam restorations with GI-reinforced undermined walls might be suitable for restoration of freshly erupted permanent first molars with extensive caries.

First permanent molar teeth (FPMT) erupt slowly and without any side effects among the 6-8 year old children. Sweet snacks consumption, parents’ unawareness about existence of these teeth and lack of attention to oral health care cause early caries among children in these ages. First permanent molars (FPMs) have a very important role in oral cavity among children. Therefore, missing of these teeth causes serious mastication and dental problems. In the present study, mother's knowledge on the presence of FPMs in their children’s mouth and its effect on health of these teeth were evaluated.
In this cross sectional study, 350 elementary school students of the 1st and 2nd grades and their mothers from Yasuj, Iran, were evaluated in 2015-2016. After sampling, questionnaires were used for data collection and were filled out by mothers. Then, each student was visited separately and the decayed, missing, and filled teeth (DMFT) index of FPMs was registered. Data were analyzed statistically using independent samples t-test, Mann-Whitney test and Spearman’s rank correlation coefficient.
The results showed that the difference between mothers’ knowledge score about the presence of FPMs in their children’s mouth was not significant regarding their education level, occupation and age. The same result was obtained after evaluation of DMFT index of children’s FPMT.
Mothers’ education about methods of dental caries prevention and protective oral health care is essential.

First permanent molars with poor prognosis may be candidate for timely extraction and replacement by second permanent molars. The presence of third molars should be considered in this treatment plan. The aim of the present study was to evaluate the critical developmental stages of permanent second molar and the status of third molar bud in an Iranian population. Four hundred panoramic radiographs of 7 to 11-year-old children were evaluated in this descriptive study. Data were collected from patients’ files and through phone interview with parents. The stage of tooth development in each age group was determined according to the modified Demirjian method. Statistical analysis was performed using Wilcoxon signed Rank test and Chi-Square test. Stage E (beginning of root formation) in permanent second molars had the highest prevalence among 8 and 9-year-olds in the mandible, and among 9 and 10-year-olds in the maxilla. The predominant stage of development in third molar buds was stage 0 (no evidence of bud formation) in the corresponding age groups. There was no significant difference between boys and girls in terms of developmental stages. Mandibular second and third molars were more advanced than maxillary molars in terms of development, with no gender predilection. The beginning of calcification in the furcation area of permanent second molar (Stage E, between 8 to 10 years of age) is the most proper stage to coincide with first molar extraction. However, during this time period, the signs of third molar bud formation are not detectable in many individuals, especially in the maxillary arch.