ABSTRACT
<p><b>OBJECTIVE</b>The research tended to approach applying of adjustable appliance in the treatment of obstructive sleep apnea-hypopnea syndrome (OSAHS).</p><p><b>METHODS</b>30 OSAHS patients (24 males and 6 females) participated in the adjustable group, with a mean age of (49.9 +/- 9.9) years old. AHI was (33.1 +/- 22.7) per hour. The control group consisted of 30 OSAHS patients wearing ordinary mandibular advancing appliance in the corresponding period, with age, weight and AHI at the same level. Monoblind way was designed to obtain and analyze the therapy differences. Differences in changes of upper airway, mandible and hyoid bone were also analyzed among the doctor-experience position, final adjusted position and original position.</p><p><b>RESULTS</b>AHI decreased by 85.5% in the adjustable appliance group. The change in AHI was greater significantly (P = 0.025) in the adjustable group than in the control group. In the final adjusted position, the amount of mandibular advancement was (5.8 +/- 1.4) mm [(71 +/- 26)% of the maximum range of protrusion] and that of bite opening (the distance between upper and lower incisor edges) was (4.6 +/- 1.1) mm.</p><p><b>CONCLUSIONS</b>The adjustable appliance had shown better therapy effect in OSAHS patients. The final adjusted position provided useful information on determining mandibular position using other appliances.</p>