[Intraoral protrusion devices in obstructive sleep apnea. Dental findings and possible treatments]

Mandibular advancement appliances remain effective in lowering respiratory disturbance index for 2.5-4.5 years

OBJECTIVE

The mandibular advancement appliance (MAA) is now recognized as a first-line therapy option for mild to moderate obstructive sleep apnea syndrome (OSAS). The aim of this follow-up study was to re-assess the long-term efficacy of MAAs provided to patients in a previous comparative study.

METHODS

Sixteen subjects had participated in a previous comparative study in which the efficacy and compliance of two MAAs (Klearway - K and Silencer - S) were compared in a randomized cross-over design. At the end of the previous comparative study, subjects selected the MAA they preferred. Nine chose the K and seven the S. Fifteen subjects were available for a follow-up interview and 14 (4 women and 10 men; mean ± SEM: 51.9 ± 1.7 y.o.) agreed to participate in an overnight sleep recording at a hospital sleep laboratory from January to February 2009. The mean time lag between the end of the previous comparative study and the follow-up was 40.9 ± 2.1 months (range of 2.5-4.5 years). Comparisons were made across the three polysomnographic evaluations (PSGE): baseline, the night with the appliance of their choice at the end of the previous comparative study, and the follow-up night. Subjects completed the Epworth sleepiness scale (ESS), the fatigue severity scale (FSS), and a quality of life questionnaire (FOSQ).

RESULTS

At the follow-up, the respiratory disturbance index (RDI) remained significantly lower than baseline (p<0.001). Questionnaire responses revealed that ESS, FSS, and FOSQ remained improved at follow-up (p<0.02). Body mass index (BMI) increased slightly from baseline to follow-up (p<0.05). Diastolic and systolic blood pressure and cardiac rhythm decreased significantly from baseline to follow-up.

CONCLUSIONS

The MAAs remained effective in improving RDI, sleepiness, blood pressure, cardiac rhythm, fatigue, sleep quality, and quality of life over a period of 2.5-4.5 years. The rise in BMI is a concern that merits further examination.

Diagnostic imaging and sleep medicine

Obstructive sleep apnea syndrome (OSAS) is a relatively common disorder characterized by recurrent episodes of upper airway collapse and obstruction during sleep. It results in apneic events (or in the case of partial obstruction, hypopneic events) that lead to loud snoring, hypoxia, and arousals that interrupt the normal sleep cycle. Typically, these nocturnal arousals cause patients to complain of excessive daytime sleepiness, which may interfere with routine daily activities. More importantly, when moderate to severe, OSAS can lead to a wide variety of medical complications, some of which can result in severe consequences or even death.

Oral appliances and functional orthopaedic appliances for obstructive sleep apnoea in children

BACKGROUND

Apnoea is a breathing disorder marked by the absence of airflow at the nose or mouth. In children, risk factors include adenotonsillar hypertrophy, obesity, neuromuscular disorders and craniofacial anomalies. The most common treatment for obstructive sleep apnoea syndrome (OSAS) in childhood is adenotonsillectomy. This approach is limited by its surgical risks, mostly in children with comorbities and, in some patients, by recurrence that can be associated with craniofacial problems. Oral appliances and functional orthopaedic appliances have been used for patients who have OSAS and craniofacial anomalies because they change the mandible posture forwards and potentially enlarge the upper airway and increase the upper airspace, improving the respiratory function.

OBJECTIVES

To assess the effectiveness of oral appliances or functional orthopaedic appliances for OSAS in children.

SEARCH STRATEGY

A sensitive search was developed for the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2005, Issue 3); PubMed (January 1966 to September 2005); EMBASE (1980 to September 2005); Lilacs (1982 to September 2005); BBO-Bibliografia Brasileira de Odontologia (1986 to September 2005); and SciELO (1997 to September 2005). There was no restriction of language or source of information.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials comparing all types of oral and functional orthopaedic appliances with placebo or no treatment, in children 15 years old or younger.

PRIMARY OUTCOME

reduction of apnoea to less than one episode per hour.

SECONDARY OUTCOMES

dental and skeletal relationship, sleep parameters improvement, cognitive and phonoaudiologic function, behavioural problems, drop outs and withdrawals, quality of life, side effects (tolerability), economic evaluation.

DATA COLLECTION AND ANALYSIS

Data were independently extracted by two review authors. Authors were contacted for additional information. Risk ratios with 95% confidence intervals were calculated for all important dichotomous outcomes.

MAIN RESULTS

The initial search identified 384 trials. One of them, reporting results from a total of 23 patients, was suitable for inclusion in the review. Data provided in the published report did not answer all the questions from this review, but some of them were, and the presented results favour treatment.

AUTHORS' CONCLUSIONS

At present there is no sufficient evidence to state that oral appliances or functional orthopaedic appliances are effective in the treatment of OSAS in children. Oral appliances or functional orthopaedic appliances may be helpful in the treatment of children with craniofacial anomalies which are risk factors for apnoea.