Background: Information on tooth emergence is a key indicator for demonstrating maturity in the diagnosis of certain growth disturbances and an estimation of the chronological age of the children with unknown birth records in forensic dentistry. The association of dental and skeletal maturity with chronologic age among different populations has been investigated by several researchers. Early eruption of permanent molar appears to be a unique finding at such an early chronological age. The present report aimed to present a case of early eruption of mandibular second permanent molar in a seven-year-old girl. Case Report: A seven-year-old girl was referred to the department of pediatric dentistry of Hamadan University with the chief complaint of an extra palatal tooth. Apart from the supernumerary tooth, mandibular second molars and premolars were fully erupted. Radiographic evaluation revealed a closure of the apex of the maxillary and mandibular incisors along with the first molars. For further investigations, the patient was referred to pediatric endocrinologist in order to rule out any systemic disease; however, patient’s test results did not show any systemic or hormonal problems. This case is one of the rare cases of early eruption of mandibular second molars at seven with no underlying problems. To our knowledge, no case of early eruption of second permanent molar has been reported in a seven-year-old child and early eruption of second molar appears to be a unique finding at such an early chronological age. Conclusions: Any change in sequence or timing of the normal tooth eruption is not common, and it needs prepared eyes and adequate knowledge to diagnose and examine it in a timely manner.

Background: The best and the most reliable methods to manage the dental plaque are still mechanical procedures. It has been traditionally recommended that a firm fruit such as an apple be eaten to minimize caries and control plaque at the end of a meal. However, several studies have reported contradictory findings about the microbial plaque function of the apples. Some studies, for instance, have found that apples contain sugar and, therefore, can cause plaque growth; some other researches, on the other hand, have shown that they have the potential to decrease plaque due to their mechanical plaque removal function. This study, therefore, aimed to compare the effects of apple-chewing method and that of tooth-brushing one on plaque removal. Methods: The study group included 48 healthy dental students with good oral health status, who were randomly selected to participate in this comparative, crossover clinical study. First, they were asked to brush their teeth or eat an apple. After 2 weeks, the experiment was repeated with the order reversed. Plaque indexes (PIs) were determined as before brushing/apple eating (baseline, B), immediately afterward (A), and 24 hours afterward (24). Results: Over time, there was a significant shift in the plaque index pattern between the groups (P value<0.001) but this discrepancy, in general, was not significant between the group using apple and the one using toothbrush (P value =0.495), as well as between the group using yellow apples, and the ones using red apples or the toothbrushes (P value =0.768). Conclusions: Comparing the two plaque control methods, it was found they were extremely similar; however, chewing yellow apples was discovered to be more effective method in reducing dental plaque than chewing red apples or using toothbrushes.