OBJECTIVETo reveal malocclusion of primary dentition in the suburb of Chengdu.

METHODSCross-section survey and malocclusion rate calculation were performed.

RESULTSThere are 491 children with malocclusion from total 1 279 children; the rate of malocclusion is 38.38%. The most important malocclusion in primary dentition are over bite (III degrees), anterior cross bite, edge to edge bite, early loss of deciduous teeth, fused teeth.

CONCLUSIONThe rate of malocclusion of primary dentition in the suburb of Chengdu is a little bit light. Much work should be done to prevent or treat the malocclusion of primary dentition.

Child ; China ; epidemiology ; Cross-Sectional Studies ; Dental Occlusion ; Fused Teeth ; Humans ; Malocclusion ; epidemiology ; Tooth, Deciduous

OBJECTIVES: This study aimed to investigate the clinical characteristics of congenital deciduous teeth absence and its permanent teeth performance type by using panoramic radiographs. METHODS: A total of 15 749 panora-mic radiographs of 3-6-year-old children with deciduous dentition were collected from January 2020 to December 2021. The incidence of congenital deciduous teeth absence was observed, and the abnormality of permanent teeth was recor-ded. SPSS 24.0 software was used for statistical analysis. RESULTS: The incidence of congenital deciduous teeth absence was 2.54% (400/15 749), which was found in 217 girls and 183 boys, and the difference between the genders was statistically significant (P=0.003). The absence of one and two deciduous teeth accounted for 99.75% (399/400) of the subjects. In addition, 92.63% (490/529) of mandibular deciduous lateral incisor was congenitally absent, 44.80% (237/529) of deciduous teeth was absent in the left jaw, and less than 55.20% (292/529) was absent in the right; the difference between them was statistically significant (P=0.017). The absence of 96.41% (510/529) deciduous teeth in the mandibular was significantly more than that of 3.59% (19/529) in the maxillary, and the difference between was statistically significant (P=0.000). Furthermore, 68.00% (272/400) and 32.00% (128/400) of deciduous teeth were absent in unilateral and bilateral, respectively, and the difference was statistically significant (P=0.000). Four types of congenital deciduous teeth absence with permanent teeth were observed as follows: 1) 73.91% (391/529) of permanent teeth was absent; 2) 20.60% (109/529) of permanent teeth was not absent; 3) the number of fused permanent teeth accounted for 4.91% (26/529); 4) the number of supernumerary teeth was 0.57% (3/529). CONCLUSIONS Although the absence of congenital deciduous teeth is less common than that of permanent teeth, it affects deciduous and permanent teeth to some extent. Dentists should pay attention to trace and observe whether abnormalities are present in the permanent teeth and take timely measures to maintain children's oral health.
Male ; Female ; Humans ; Tooth, Deciduous ; Dentition, Permanent ; Tooth, Supernumerary/epidemiology* ; Anodontia/etiology* ; Tooth Abnormalities/complications* ; Fused Teeth/epidemiology*

OBJECTIVEThis study aims to investigate the prevalence and distribution of teeth number and morphology abnormalities in Chinese pediatric patients' permanent teeth at the mixed dentition stage by performing panoramic radiographs analysis.

METHODSA total of 4 347 panoramic radiographs of pediatric patients aged 5 years to 15 years who were admitted to the hospitals from September 2011 to September 2013 were reviewed. The presence of teeth number and morphology abnormalities were recorded as follows: congenitally absent teeth, supernumerary teeth, odontoma, microdontia, fused teeth, dilaceations, and cusp deformity. SPSS 16.0 software was used for statistical analysis.

RESULTSThe prevalence of teeth number and morphology abnormalities in pediatric patients' permanent teeth was 31.79% (1,382/4,347). The prevalence was higher in males. Significant difference between the genders was observed (P < 0.05). Tooth agenesis, the most frequent dental anomaly (15.00%, 652/4,347), was considerably common in females; supernumerary teeth (12.61%, 548/4,347) followed, which was significantly common in males. Both differences were statistically significant (P < 0.05). The levels of prevalence of both microdontia and dilacerations were 4.00% (174/4,347) and 2.16% (94/4,347). The prevalence of cusp deformity, odontoma, and fused teeth were relatively low at 0.74% (32/4,347), 0.51% (22/4,347), and 0.39% (17/4,347), respectively.

CONCLUSIONThe prevalence of teeth number and morphology abnormalities in children's permanent teeth at the mixed dentition stage is apparently high. Tooth agenesis and supernumerary teeth are the most frequent. Panoramic radiograph is an efficient method for the early diagnosis of teeth number and morphology abnormalities. This method can assist pediatric dentists to formulate treatment plans for children at the appropriate time.

Adolescent ; Child ; Child, Preschool ; China ; epidemiology ; Dentists ; Dentition, Mixed ; Dentition, Permanent ; Female ; Fused Teeth ; epidemiology ; Humans ; Male ; Odontoma ; epidemiology ; Patient Care Planning ; Prevalence ; Radiography, Panoramic ; Sex Factors ; Tooth Abnormalities ; diagnostic imaging ; epidemiology ; Tooth, Supernumerary ; diagnostic imaging ; epidemiology