Dens invaganatus is a type of abnormal morphological differentiation because of the involution in crown surface before tooth calci-fication,it is mostly found in maxillary lateral incisor teeth and rare in incisor.A case of a malformed lingual groove of left maxillary central incisor with 2 root canals is reported in the paper.

The mandibular canine usually has a single-root with a single canal.A case of a Hui nationality patient who has a mandibular ca-nine with two root canals is reported in this paper.

Objective: To explore the correlation between malocclusion and body image issues in college students. Methods: A total of 1 851 students in three universities in Jingmen were selected by using stratified cluster sampling method. Angle s classification of malocclusion was used to determine the number of three types of malocclusions. Body image issues were self reported and its relationship with different types of malocclusions was explored. Results: The proportions of Classes Ⅰ, Ⅱ and Ⅲ malocclusion in college students with malocclusion were 71.21%, 16.32%, and 12.47%, respectively. The detection rates of body image issues among students with Classes Ⅰ,Ⅱ and III malocclusions were 36.64%, 54.78% and 65.83%, respectively. No significant difference were found in the detection rates of sexual organ issues and gender issues in college students with different types of malocclusions( χ 2= 0.75, 0.53, P >0.05). There were significant differences in the detection rates of appearance troubles (27.59%, 33.12%, 50.83% ) and stature troubles ( 24.09% , 31.21%, 44.17%) in students with Classes Ⅰ, Ⅱ and Ⅲ malocclusions( χ 2=5.62, 2.89, P <0.05). Conclusion The prevalence of body image issues in college students increases with severity of malocclusions. Appearance and stature troubles are issues mostly concerned among college students. Psychological evaluation for students with Class Ⅲ malocclusion should be especially emphasized when administrating orthodontic treatment.