Sleep disordered breathing (SBD) is a spectrum of chronic disease conditions that are united by a reduced oxygen perfusion while sleeping. Recent studies suggest 1-3% of children suffer from SBD. Severe cases of SBD are often identified early, often with treatment beginning before 2 years old. However, many mild to moderate cases of SBD go undiagnosed, leaving a child with a chronic disease condition with significant impact on the systemic health and craniofacial growth.
Because even mild SBD is often associated with specific oral and craniofacial characteristics (narrow maxilla, posterior cross bite, long anterior face height, anterior open bite, weak chin projection), orthodontists are uniquely positioned to screen for mild to moderate cases of pediatric SDB. Therefore all dentists and orthodontists should be confident screening for SDB, and co-coordinating appropriate and timely referrals.
The most common etiology of SBD in children is adenoid and tonsil hypertrophy leading to upper airway obstruction. However, adeno-tonsillar hypertrophy is not the only cause of SBD. Any form of nasal obstruction – whether a deviated septum, chronic rhinitis, or other pathology – could lead to similar symptoms. While tonsil and adenoid hypertrophy often resolves on it’s own during late adolescence, for those children with SBD the physical, psychiatric, and emotional damage is often permanent.
With the growing number of children suffering from obesity, a etiologyof pediatric SDB is becoming increasingly common. Obese children may present with adult-like forms of SDB commonly characterized by mandibular retrognathia and increased neck circumferance.
In addition to the common primary etiologies, dentists and orthodontists should be familiar with, and able to identify common co-morbidities and risk factors. These conditions may work with negative synergy and co-contribute to the development or worsening of SDB. Dentists should be able to collaboratively recognize the following conditions in children suspected to have SDB:
- Chronic allergies
- Chronic environmental irritants (eg. indoor pets, parent’s who smoke)
- Pre-term birth
- African decent ethnicity
Currently, the definitive diagnosis of SBD is only available with overnight polysomnography (PSG). Similarly, the reference standard diagnosis of upper airway obstruction is flexible tube endoscopy. Rarely is a dentist able to provide definitive diagnosis of SBD or define its precise etiology. However orthodontists do have tools at their disposal to provide accurate screening.
There are numerous questionnaires available to screen SDB. The most widely accepted for children is the Pediatric Sleep Questionnaire (PSQ)
. Dentists should become familiar with the questionnaire, using it both to improve and supplement their own clinical judgment.
Lateral cephalograms are a fair screening tool for evaluating adenoids, but tend to overestimate their size and produce more false positive findings that ideal. For that reason, a significant finding on a ceph is insufficient to warrant referral to an otolaryngologist. Screening accuracy can be improved if lateral cephalograms are combined with a thorough medical history and clinical exam that identified collaborative signs and symptoms of SDB.
When warranted for dental or orthodontic diagnosis and treatment planning, secondary airway evaluation of cone beam computed tomography (CBCT) can provide accurate assessment of stable tissues. Adenoid evaluations in particular are very accurate. However, CBCT is a static image, tissues that change dynamically may not be represented as accurately. Because of this inherent weakness, CBCT must still be collaborated with clinical findings and medical history.
As already discussed, dentists and orthodontists have an invaluable role in early detection and screening of upper airway disorders and SDB. A thorough understanding of radiographic strengths and limitations combined with a developed clinical exam and history taking can yield accurate screening. Timely diagnosis and referral often can prevent damaging disease sequelae.
Orthodontists may also have a role in treating select forms of SDB. There is growing evidence that skeletally directed orthodontic treatments might provide therapeutic benefit. However any orthodontic treatment MUST be preceded by a proper diagnosis provided from otolaryngology and sleep medicine colleges. For example, orthodontic treatment will never resolve SDB that is secondary to large polyps obstructing the nasal airway.
Rapid maxillary expansion may be one orthodontic treatment with airway benefit. For children with combined maxillary transverse constriction and hypertrophic adenoids, recent evidence suggests adenoidectomy and rapid maxillary expansion (RME) were both necessary to fully resolve symptoms. However, RME is not a “cure” for nasal obstruction. While numerous studies demonstrate improved symptoms, very rarely are complete cures observed.
Likewise evidence exists that mandibular repositioning appliances can be successful for managing SBD for children with mandibular retrognathia as the primary etiology. For these children, SBD management would be very similar to adult management of SDB for which a strong body of evidence exists. Again, orthodontists must be very careful about promising “cures” through enhanced mandibualar growth. Most children with SDB have a vertical direction of growth, and these are precisely the children with the poorest orthopedic prognosis. Children successfully managed with mandibular repositioning appliances are good candidates for surgical mandibular advancement as adults.
Orthodontists have a valuable role as co-contributors to multi-disciplinary management. Early detection and in select treatment procedures are essential parts to managing children with SDB. However, no dentist or orthodontist should ever attempt to treat SDB alone.