Trace elements, such as aluminum, copper, manganese, and zinc, exist in minute amounts in living organisms, and are mainly taken into the human body through food or water ingestion. Some diseases and disorders are known to be induced by a deficiency or excess intake of some trace elements. In the present study, deciduous enamel samples were obtained and immersed in artificial saliva (pH 6.2 or 5.5), then values for the concentration of aluminum eluted per unit area of the enamel surface were examined for correlations with subject tooth and oral conditions. The concentration of aluminum eluted from sound regions of enamel from teeth with caries experience was significantly higher as compared to that from enamel of sound teeth following immersion in artificial salvia with a pH value of 5.5. Although the examined sound teeth had not experienced dental caries, other teeth in the same subject may have had caries. Therefore, the concentration of aluminum from sound teeth was compared with those from subjects without, with from 1 to 5, and with 6 or more carious teeth. Those findings showed that the concentration of aluminum was greater in sound teeth from donors with 6 or more carious teeth. In the same manner, aluminum concentrations from sound regions of enamel in teeth with caries experience were compared among subjects with 1 to 5, 6 to 10, and 11 or more carious teeth. Those findings also showed that the concentration of eluted aluminum was greatest in samples from subjects with 11 or more carious teeth. Together, our results suggest that a higher amount of aluminum is eluted from enamel of caries prone teeth as compared to that from healthy teeth when exposed to saliva with a pH value of 5.5. The review article reports copper and strontium levels in mixed saliva obtained from children. The concentration of copper in mixed saliva was greater in subjects with untreated decayed teeth, while that of strontium in mixed saliva was greater in subjects with untreated or treated carious teeth. These findings suggest that copper is eluted from untreated decayed teeth, while strontium is eluted from carious teeth regardless of caries treatment experience.

Introduction : In pediatric dentistry, early determination of various types of malocclusion and bad oral habits is important for diagnosis. Child patients with limited dental treatment experience often feel stress during conventional impression taking with an alginate impression material. The aim of this study was to assess preferences and procedure times for impression techniques in pediatric sub jects who underwent impression taking with both a conventional technique and a digital technique with an intraoral scanner. Materials and Methods : In 6 child patients, conventional impressions were performed using an algi nate impression material as well as digital impressions with an intraoral scanner (TRIOS ^Ⓡ;3 Shape,Copenhagen, Denmark). The mesiodistal crown width of the maxillary left first molar in each subject was compared between the conventional and digital impression results. In addition, each procedure was timed and subject preferences regarding the impression techniques were assessed with a question naire survey given immediately after the procedures were concluded. Obtained data were analyzed us ing Mann-Whitney's U test. Results : There were no significant differences for mesiodistal crown width between the conventional and digital impressions. Although the chair time required to take the conventional impression was shorter than that for the digital impression, all subjects stated that the digital impression procedure was more comfortable. Conclusion : For pediatric patients, a digital impression technique may be more useful than a conven tional method.

The aim of this study was to characterize various conditions exhibited by first-visit patients treated at a pediatric dentistry department of a university hospital in central Tokyo who had experienced dental injury in order to develop treatment guidelines from the perspective of a higher order medical institution. We conducted a survey of 437 children who first visited our hospital between April 2011 and March 2016 for traumatic dental injuries.

1.During the 5-year study period, 11.0% of the first-visit pediatric patients had experienced a traumatic dental injury.

2.Dental trauma was more often seen in boys. During the study period, 186 boys (59.2%) and 128 girls (40.8%) visited for treatment of primary teeth, and 61 (69.3%) and 27 (30.7%), respectively,came for treatment of permanent teeth.

3.Two-year-old patients were the most frequent group (21.5%) to experience trauma in primary teeth,though the 1- (19.7%) and 3-year-old (15.3%) groups showed similarly frequency. Eight-year-old patients constituted the most frequent group (5.3%) to experience trauma to permanent teeth.

4.A majority of patients were referred from another dental clinic ([267 (61.6%) vs. 170 (38.9%)].

5.The total number of traumatized primary teeth was 506 (76.7%) and that of permanent teeth was 154 (23.3%). Thirty-three of the patients only experienced injury to soft tissues.

6.A total of 377 (62.9%) teeth exhibited luxation, while 166 (27.7%) were fractured and 56 (9.3%) were discolored. Two years old was the most frequent age for mobility and concussion, intrusive luxation, crown fracture, and discolored teeth, and those conditions decreased in frequency with age. On the other hand, 1-year-old patients most often exhibited dislocation, a dental condition that primarily occurs at an early age. Additionally, the number of root fractures peaked at the age of 4 years, with 111 permanent teeth (61.0%) exhibiting luxation and 70 (38.5%) fracture.

7.Dental observation was the treatment option most often chosen for both primary and permanent tooth cases. Notably, that treatment was performed at a high rate in cases with intrusive luxation and discoloration. Tooth extraction was not performed for permanent teeth.

The present results suggest differences in injury patterns and treatment approaches between cases of primary and permanent teeth. We concluded that communication with dental clinics in regional com munities is important. Furthermore, pediatric dentists at university hospitals should be sought to address dental trauma in younger children, as they typically have a higher level of dental skill and greater knowledge.

Tooth gemination rarely occurs among permanent mandibular posterior teeth. Furthermore, fusion has a similar clinical appearance, making differential diagnosis difficult. Gemination is generally defined as division of a single tooth germ by invagination, whereas fusion is a conjunction of 2 isolated tooth germs. However, a geminated tooth can also be regarded as fusion when ordinary and supernumerary teeth are involved. We report here gemination of a permanent mandibular second molar in a 12-year-old girl. A form abnormality of the mandibular left second molar in a healthy girl was seen in X-ray images obtained at the age of 5 and 7 years old in examinations conducted at a private dental clinic, and the tooth erupted at the age of 12 years. Typically, a geminated tooth has a large crown with complicated fissures and ridges, thus utilization of 3 D imaging modalities, such as CBCT, is crucial for correct diagnosis and establishment of an adequate plan for prevention of dental caries in geminated teeth.

Odontogenic maxillary sinusitis is an odontogenic infection caused by inflammation spreading from the apical area to the maxillary sinus. Deciduous teeth are rarely causative factors, as a succedaneous permanent tooth germ is present between those teeth and the bottom of the maxillary sinus. We report here a case of odontogenic maxillary sinusitis caused by apical periodontitis in the maxillary second deciduous molar. A 6-year-5-month-old girl visited our hospital with buccal tenderness and gingival swelling in the area of the left maxillary deciduous molar. CT findings showed mucosal hypertrophy in the bottom of the left maxillary sinus, with interruption of bone continuity in that area also confirmed. Under a diagnosis of odontogenic maxillary sinusitis on the left side caused by apical periodontitis of the left maxillary second deciduous molar, anti-inflammatory treatment was given, then the causative tooth was extracted and a space maintainer attached. The patient was then followed for 1 year 11 months until eruption of the left maxillary second premolar had occurred. For a better understanding of the factors involved in this case, we compared CT images obtained at the time of the first consultation with those obtained 1 year 2 months later, with reference planes set for analysis as follows. A sagittal reference plane was established on the basis of the anterior nasal spine (ANS), posterior nasal spine (PNS), and center of the incisor foremen. A horizontal reference plane including the ANS and PNS, and perpendicular to the sagittal reference plane was also established. Finally, a frontal reference plane was set perpendicular to those 2 planes and contained the ANS. Furthermore, the ANS was established as the reference point (O). Mucosal changes in the bottom of the maxillary sinus and conditions leading to eruption of the succedaneous permanent tooth germ in the bone were analyzed using these reference planes. Regression of mucosal hypertrophy and improvement in the position of the succedaneous permanent tooth germ were evaluated in a quantitative manner. The reference planes utilized in the present study were found useful for comparing CT images obtained over time.

An impacted tooth can occur from a variety of causes, while cases of multiple impacted teeth accompanied by focal bony overgrowth are rare. We report here a case of impacted mandibular incisors accompanied by overgrowth of surrounding alveolar tissue in the mixed dentition stage. An 8-year-old boy was referred to our hospital from a general dentist for abnormal swelling of alveolar tissue around the left primary incisors in the mandible. The permanent lower left incisors remained unerupted. Under a clinical diagnosis of dentigerous cyst with retained primary teeth, the lower left primary incisors were immediately extracted, while the lower central incisor erupted naturally at 7 months after surgery. Bone mass around the left incisors showed a progressive increase at around the same time, thus, following consultation with his mother, the lower left incisors were removed along with overgrown bone mass under general anesthesia. The pathological diagnosis was reactive bone augmentation. The cause of bony overgrowth around the lower left incisors in the present case is unknown. Cases of impacted permanent incisors accompanied by uncontrollable bony overgrowth are rare and this report provides important findings regarding eruption disturbance in the mixed dentition stage.

Inverted and impacted maxillary incisors are generally treated by extraction or fenestration-traction,with the angle of the impacted tooth a critical factor for treatment selection. When the angle between the impacted tooth and occlusal plane is greater than 90°, extraction is conventionally chosen. Here,we report treatment of a 7-year-old boy referred from a primary dental clinic who had a completely inverted and impacted maxillary right central incisor, as well as impacted mesiodens. Since the angle of the impacted incisor was nearly 180°and bone support for fenestration-traction would be lost after mesiodens extraction, we employed a novel method for treatment. Following extraction of the primary central incisor and mesiodens, the impacted central incisor was gently removed and then replanted in a correct orientation using a bone substitute material to fix the tooth. The replanted incisor spontaneously appeared within 2 weeks and its mobility remained at the latest examination. Furthermore, electrical pulp diagnosis findings indicated that the pulp remained vital. On the other hand, root development stopped at half the length of the healthy side, thus the root canal was not developed, though the pulp remained vital. At the time of surgical treatment, we noted that the length of the impacted central incisor was only one-quarter of normal, indicating that it was premature for replantation use. Nevertheless, the post-operative course has remained uneventful for 5 years 8 months after replantation. We plan to carefully observe the patient for an extended period.