Effects of a mandibular repositioner on obstructive sleep apnea

doi:10.1067/mod.2000.104831

American Journal of Orthodontics and Dentofacial Orthopedics

Volume 118, Issue 3, September 2000, Pages 248-256

https://doi.org/10.1067/mod.2000.104831 Get rights and content

Abstract

The purpose of this study was to investigate the effects of a mandibular repositioner on airway, sleep, and respiratory variables in patients with obstructive sleep apnea. Twenty-two patients selected for this study were confirmed with a diagnosis of obstructive sleep apnea based on initial nocturnal polysomnography. The patients were fitted with a mandibular repositioner designed to hold the mandible anteroinferiorly. Six months later, an outcome polysomnographic study was undertaken for each patient with the appliance in place. Lateral cephalometric radiographs in the upright position were also obtained before and after 6 months of treatment. The respiratory disturbance index decreased in 21 of the 22 patients with the appliance in place. The mean respiratory disturbance index of the 22 patients decreased significantly from 40.3 to 11.7 events per hour (P <.01). Some 59.1% of subjects were considered a treatment success with follow-up respiratory disturbance index < 10 events per hour. The mean minimum blood oxygen saturation level during sleep also improved significantly from 73.4% to 81.3% (P <.01). The mandibular repositioner was constructed to position the mandible at 75% of the maximal mandibular advancement and with a 7 mm opening between the upper and lower incisors, and no aberrant effect on temporomandibular joint was noted. The retropalatal airway space increased and the cross-sectional area of the soft palate and the vertical distance of the hyoid bone to the mandibular plane decreased significantly. The tongue posture became significantly flatter. A significant linear correlation was found between the reduction in apnea index and specific craniofacial skeletal structures (length of anterior cranial base, mandibular plane angle, and upper to lower facial height ratios, P <.05). Subjects with a smaller reduction in apnea index tended to have shorter anterior cranial bases, steeper mandibular planes, and smaller upper to lower facial height ratios. We conclude that a mandibular repositioner may be an effective treatment alternative for obstructive sleep apnea and that a reduction in the frequency of apneic episodes is mainly attributed to the effects of the appliance on oropharyngeal structures. (Am J Orthod Dentofacial Orthop 2000;118:248–56).

Section snippets

Selection of patients

Patients recruited to this study were diagnosed with OSA by overnight polysomnography at the Sleep Disorder Center, Beijing Union Hospital. Patients with a respiratory disturbance index (RDI) of less than 10 events/hour and with an apnea index (AI) of less than 5 events/hour were excluded from this study. Edentulous patients or those with severe periodontic or temporomandibular joint disease were also excluded. Twenty-two patients (mean age, 58.9 years; range, 40 to 68 years) with symptomatic

Cephalometric evaluation

Two lateral cephalometric radiographs for each patient were obtained before and after treatment with the patient sitting and awake in an upright position with the Frankfort horizontal plane parallel to the floor. The dorsum of the tongue was coated with a barium sulphate paste mixed with glycerine to enhance the outlines of the tongue and pharyngeal soft tissues. For the first lateral radiograph, the patients were instructed to lightly contact their back teeth in central occlusion; for the

Polysomnographic analysis

Based on their initial RDI, the 22 patients were classified into 2 groups with different severity, 14 were severe (RDI > 30) and 8 were mild-to-moderate (RDI ≤ 30). The mean RDI significantly decreased from 40.3 to 11.7 events/hour (P <.01) (Table I).As shown in Fig 5, RDI decreased with appliance use in 21 of 22 patients.

. Respiratory disturbance index before and after treatment with mandibular repositioner in OSA patients.

Thirteen of 22 patients (59.1%) were considered treatment successes

Discussion

Optimal treatment for OSA results in the reduction of apneic episodes, as can be achieved with CPAP, but the treatment might be considered effective with a reduction of RDI to below some defined level. A number of studies have evaluated the efficacy of OA, and success rates, although defined differently, are generally reported between 20% and 80%.10, 11, 17, 18 According to the definition of treatment success used in this study (follow-up RDI < 10 events/hour), treatment with MR was successful

Conclusions

1.
The results of this study showed that the MR may be an effective therapeutic alternative in OSA patients with varying severity; it is most effective in the patients with mild-to-moderate OSA.
2.
With respect to the cephalometric variables described, a change in airway size was localized to an increase in the retropalatal airway space.
3.
A significant linear correlation was found between the reduction in AI and specific craniofacial skeletal structures.

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^*: Reprint requests to: Alan A. Lowe, DMD, Dip Orthodont, PhD, FRCD(C), Professor and Chair, Division of Orthodontics, Department of Oral Health Sciences, Faculty of Dentistry, The University of British Columbia, 2199 Wesbrook Mall, Vancouver, BC, Canada V6T 1Z3; e-mail, [email protected].

^**: Am J Orthod Dentofacial Orthop 2000;118:248–56

View full text

Original ArticleEffects of a mandibular repositioner on obstructive sleep apnea*,**

Abstract

Section snippets

Selection of patients

Cephalometric evaluation

Polysomnographic analysis

Discussion

Conclusions

Am J Orthod Dentofacial Orthop

Lancet

Chest

Chest

Am J Orthod Dentofacial Orthop

Chest

Chest

Chest

The occurrence of sleep disordered breathing among middle-aged adults

N Engl J Med

Sleep-related breathing disorders. 4. consequences of sleep disordered breathing

Thorax

Obstructive sleep apnoea: a cephalometric study

Cervico-craniofacial skeletal morphology

Eur J Orthod

Obstructive sleep apnoea: a cephalometric study

Uvulo-glossopharyngeal morphology

Eur J Orthod

Cephalometric analysis and flow-volume loops in obstructive sleep apnoea patients

Sleep

Dental appliances for the treatment of obstructive sleep apnea

J Am Dent Assoc

Original Article
Effects of a mandibular repositioner on obstructive sleep apnea*,**