Background:  The prevalence of obstructive sleep apnea (OSA) has been reported to be 11.4% in Thai population and has been increase in elderly patients especially those who suffer from cardiovascular disease. Thai elderly people loss 13.38 teeth/person and approximately 7.2 % of them are edentulous. Edentulism causes a loss of vertical dimension that may affect upper airway by reducing retropharyngeal space and tone of the pharyngeal musculature and patients subsequently develop OSA. The consequences of OSA lead to a pathological cascade that is responsible for cerebrovascular and cardiovascular diseases.

Objectives: This study aimed to investigate the prevalence and risk factors, which may be associated with OSA in edentate patients.

Materials and Methods: 131 edentate patients previously delivered complete dentures during 2013-2015 at Faculty of Dentistry, KKU were recruited for telephone interview using modified Berlin questionnaire (Thai). Of those, 55 patients were high OSA risk. Twenty subjects in high OSA risk group were randomly selected to have sleep test for further diagnosis of OSA using portable polysomnography. All data including gender, age, neck circumference, BMI, systemic diseases, oropharyngeal space classified by Mallampati’s score, lateral pharyngeal wall, ridge relation, torus palatinus and torus mandibularis, tongue size and tongue position were collected by history taking together with physical and oral examination

Results: Descriptive statistics revealed that prevalence of OSA was 44.99% in edentulism. The Chi-Square test (P value= 0.032) and multiple logistic regression (backward and stepwise) showed that risk factor associated with OSA was only Mallampati’s score level 4 (OR=16.00). Gender, age, neck circumference, BMI, systemic diseases, lateral pharyngeal wall, ridge relation,  torus palatinus and torus mandibularis, tongue size and tongue position were, however, not correlated with OSA in our sampled edentate patients.

Conclusions:

Mallampati’score level 4 is an important risk factor of OSA in edentate patients. This oral manifestation can easily be examined and identified during dental treatment. Therefore, dentist could be the first health profession to screen, give advice or refer edentate patients who are at risk of OSA to physician.

Keywords: Obstructive sleep apnea (OSA), Edentate, Mallampati’score