We investigated the trend of patients with jaw deformity in the past decade at Niigata University Medical and Dental Hospital. We also compared the present results with those of our previous report in 2000. The subjects consisted of 525 jaw-deformity patients registered at the Department of Orthodontics, Niigata University Medical and Dental Hospital between January 2000 and December 2009. The number of subjects who underwent orthognathic surgery in our hospital was 767 in the same ten-year period.
The items examined were as follows:
I. Ratio of jaw-deformity patients to all new outpatients registered
II. Sources which referred jaw-deformity patients to our department and reference rate
III. Annual number of jaw-deformity patients and gender distribution
IV. Age of patients at the first examination and at the start of presurgical orthodontic treatment
V. Classification of malocclusion at the first examination
VI. Chief complaints of the patients
VII. Number of orthognathic surgeries and their procedures.
The ratio of jaw-deformity patients to all new outpatients registered from 2000 to 2009 was approximately 20%, among whom jaw-deformity patients introduced by other hospitals accounted for 82.1%. Both ratios were slightly higher than in our previous investigation in 2000. In terms of annual changes in jaw-deformity patients, the number of patients tended to decrease after a peak of 75 in 2002, and then slightly increased after 2007. The ratio of males to females was about 1:2. Regarding the age at first examination and the start of presurgical orthodontic treatment, most of the patients involved were from 14 to 19 years old.
Mandibular prognathism accounted for 63.5%, which was the most frequent antero-posterior malocclusion in the examined patients. Concerning vertical and horizontal malocclusions, open bite and midline deviation were the most frequent with 25.0% and 48.6%, respectively.
As for chief complaints, 55.2% of the complaints concerned malalignment, followed by facial appearance, masticatory disturbance, TMJ disturbance, opinions of other persons, pronunciation disorder, and others. However, the ratio of patients who regarded improvement of the face as one of the chief complaint was very high, at 79.4%, compared with the previous results in 2000.
In terms of surgical procedure, two-jaw surgery was the frequent method accounting for 50-65%. It was especially high in 2009 (77.4%).
According to the requests of patients, it is considered that two-jaw surgery may increase in the future.