Analysis of congenital deciduous teeth absence and its permanent teeth phenotype / 华西口腔医学杂志

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.

The effects of hearing on consonant discrimination in postoperative cleft palate patients / 实用口腔医学杂志

Objective:To investigate the effect of hearing on consonant discrimination in postoperative cleft palate patients.Meth-ods:30 subjects after surgery of cleft palate were examined for hearing and evaluated for speech,error frequencies of consonants were counted.According to the Chinese tone frequency and intensity distribution and measurement table of dysarthria in Mandarin,hearing and speech were divided into 3 ranks respectively.Spearman rank correlation analysis was used to determine the relation of consonant discrimination with hearing.Results:Higher error frequency of consonants (form high to low)were [t],[ts],[k],[],[s],[t] and [k'].There was close correlation(P ＜0.05)between hearing and discrimination of consonants including [t],[t'],[k],[k'], [t],[t'],[],[ts],[ts'],[s],[t],[t'],[]and [],while the discrimination of consonants [b],[m],[f]and [n]showed no significant correlation with hearing(P >0.05).Conclusion:The hearing of postoperative cleft palate patients affect the consonant discrimination that mainly in the high frequency region,while low and middle frequency consonant discrimination have no influence. Other feedback channels need to be considered in speech training for high frequency consonants.