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.