• Chanchai Hosanguan D.D.S., M.S.
• Suthean Umpronsirirat
• Poowadis Kosonittikul

Objectives Orth odontic uptake among adolescents appears to increase in Thai society. The purposes
of this research were to assess the rate of fixed orthodontic treatment experiences among first-year
students at Chulalongkorn University (CU) and to identify its associating factors.

Materials and methods A cross-sectional survey was conducted on a stratified-clustered sample
of 800 first-year CU students. About 635 completed questionnaires were returned, giving a 79.4%
response rate.

Results Approximately 32.8 % of subjects experienced fixed orthodontic treatment; divided into
20.6% with orthodontic treatment completed, 8.5% with undergoing orthodontic treatment, and 3.6%
with orthodontic treatment discontinued. There were significant relationships between orthodontic
treatment experience and several factors, including sex (p < .001), faculty discipline (p = .001), history
of relatives' orthodontic treatment (p = .001), history of siblingsû orthodontic treatment (p < .001),
dental service utilization behavior (p < .001), and satisfaction with current tooth alignment (p =.001).

Conclusion In conclusion, CU students experience a relatively high rate of fixed orthodontic
treatment. Certain social characteristics exert an influential role on orthodontic treatment rates. Therefore,
considerations on psychosocial dimensions are needed in order to understand the decision making
process of orthodontic care.

(CU Dent J. 2005;28:199-210)