Abstract:

Objective To study the occurance rate and the morphology of the anterior nasal spine and its relationship with the age and sex. Methods The occurance rate of anterior nasal spine in 1000 cases of craniofacial(including maxilla) transverse CT, and the morphology of the anterior nasal spine and its relationship with the age and sex, were observed, counted and analized using statistical analysis. Results The overall incidence of anterior nasal spine was 98.20% (982/1000). The incidence rates of anterior nasal spine in male and female were 99.06% (629/635), 96.71% (353/365) respectively; the male was higher than female (χ2=7.1970 P<0.05). The incidence rate in the children group (age ≤7 years), adolescent group (aged 8-18 years) and adult group (age> 18 years) were 92.59% (75/81), 99.25% (133/134), 98.60% (774/785) respectively. The occurance rates of anterior nasal spine in adolescents(99.25%%) and adults(98.60%) were higher than that in children(92.59%). The triangle pattern (64.66%) was the most common type of anterior nasal spine. The triangle pattern was more common in women (74.22%), double rod pattern and the single rod pattern were more common in men(28.46%,8.90%). There was no significant incidence difference of irregular pattern between male and female(3.34%,1.98%). Double rod pattern had the highest occurance rate in young people(58.65%).The incidences of triangle pattern in children(64.00% ) and adults(71.32%) were higher than that in adolescents(26.32%). Single rod pattern had the highest occurance rate in young people(12.78%). The distribution of irregular pattern had no significant difference among different age groups(2.67%,2.56%,2.97%). Conclusion The vast majority of people (98.20%) have anterior nasal spine. The most common shape of the anterior nasal spine is triangle. The occurance rate and shape of anterior nasal spine are related to the sex and age.

Key words: Anterior nasal spine, Anatomy, Sectional anatomy, Computed tomography, Human