Validity assessment and determination of the cutoff value for the Index of Complexity, Outcome and Need among 12-13 year-olds in Southern Chinese / 国际口腔科学杂志·英文版

To validate the use of the Index of Complexity, Outcome and Need (ICON) in assessing orthodontic treatment need among 12-13 year-olds in southern China, we determined the threshold value of ICON based on Chinese orthodontists' judgments. The samples consisted of 335 students in grade 7 from 16 randomly selected middle schools in Chengdu, China. Three associate professors provided ICON scores for each participant and the results were compared with the gold standard judgments from 25 experts on treatment needs. Based on the gold standard, 195 casts belonged to the treatment category, while the rest 140 belonged to the no-treatment category. With the international cutoff point of 43, the sensitivity and specificity of the ICON score were 0.29 and 0.98.The best compromise between sensitivity and specificity in Chengdu, compared with the gold standard, was found at a cutoff point of 29, and the sensitivity and specificity were 0.88 and 0.83. When used to evaluate the treatment need of 12-13 year-olds in southern China, the international ICON cutoff value did not correspond well with Chinese orthodontists' judgments; a lower cutoff value of 29 offered a greater sensitivity and specificity with respect to expert orthodontists' perception of treatment need.

Analysis of clinical features and mutation associated with oligodontia / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the mutation characteristics of paired box homeotic gene 9 (PAX9) and muscle segment homeobox gene 1 (MSX1) of patients with congenital oligodontia.</p><p><b>METHODS</b>Clinical manifestations were recorded by taking complete oral examinations in patients with congenital nonsyndromic oligodontia and some of his normal family members. Pedigree information was confirmed by extended interviews and a pedigree was constructed. Inheritance mode and clinical features were analyzed. Assessment of crown width compared to normal value of crown width in Chinese people was based on the registrations and measurements of study cast. Comparison of craniofacial form, malocclusion types and characteristics were conducted via cephalometric analysis by taking lateral cephalometric radiographics. Venous blood samples were collected and DNA was extracted from leukocytes. DNA sequencing and mutation analysis were analyzed in exon 1, 2, 3, 4 of PAX9 and exon 1, 2 of MSX1 coding region by polymerase chain reaction (PCR).</p><p><b>RESULTS</b>The teeth shape abnormality of the patient was noticed by a measured smaller crown width compared to normal values of crown width in Chinese people. The result of cephalometric analysis indicated no obvious inherited tendency in the proband in terms of facial osseo type and jaw bone pattern. One mutation was found in the proband and his mother in exon 3 of PAX9, the missense mutation G718C causing a conservative change A240P was present. Mutation was not found in MSX1.</p><p><b>CONCLUSION</b>These findings suggest that the missense mutation G718C in exon 3 of PAX9 is likely the cause of oligodontia.</p>

Facial profile preference among four panels / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To determine the facial profile preference among four groups of persons and the influence of vertical proportion and skeletal anteroposterior relation on facial profile esthetics.</p><p><b>METHODS</b>One hundred and twenty persons, comprising of adult patients, adolescents' parents, laypersons and orthodontists, participated this study. The subjects were asked to rate 27 silhouettes which represented the male facial profiles with various vertical proportion and anteroposterior relation.</p><p><b>RESULTS</b>The silhouette II-1s scored highest while the one III-4s scored lowest (P < 0.05). The silhouette I-normal was rated highest by orthodontists while the ones II-normal and II-1s were rated highest by other three groups. The silhouette III-4s was scored lowest by all groups (P < 0.05).</p><p><b>CONCLUSIONS</b>Vertical discrepancy had influence on Chinese male facial profile esthetics and the influence was related to the degree of vertical malformation and skeletal anteroposterior relation. Class III skeletal pattern had the most negative influence on male profile esthetics. The four panels had different esthetic standard. The preference of facial profile esthetics was related to orthodontic education background rather than gender or age.</p>