**3. Extraoral traction appliances**

There are different ETA, bone or teeth anchored (**Figure 3**) that, if used well, cause anterior traction of the upper jaw.

One can have a maxillary retrusion, a mandibular prognathea, or a mixture of the two. Respiratory problems can arise with maxillary retrusion when the maxillary is back positioned and encroaches on the nasopharyngeal airway.

Research conducted over the past decade has shown associated improvements in airway size with maxillary protraction [21].

Existing controlled clinical studies on humans show that ETA for skeletal Class III intervention might be related to broader airway proportions, mostly minor in

**Figure 3.** *Rapid maxillary expansion, prepared for traction, if necessary.*

magnitude [22]. Positive stable changes in the airway dimensions of Class III subjects were obtained by treatment with RME and ETA [23].

Maxillary protraction is a complement of RME. It is used only if necessary; only those with problems in the sagittal plane may need ETA when anteroposterior dimension mismatch between the maxilla and the mandible. Most cases that require RME do not require ETA. The best time to use ETA is immediately after finishing the RME, taking advantage of the lack of union of the sutures and superior displacement of the bones, as they are less trapped.

While RME is responsible for the transverse maxillary increase, ETA becomes important in the anteroposterior dimensions.

### **4. Obstructive sleep apnea and obstructive sleep apnea syndrome**

A small-scale upper jaw and/or mandible can predispose kids to sleep-disordered breathing, which is a continuum of gravity from snoring to OSA. Related health consequences, such as cardiovascular and neurocognitive functions, have not yet been systematically referred [24].

OSA often goes undiagnosed and affects approximately 5% of the population. Obstructive Sleep Apnea Syndrome (OSAS) is a more serious form of OSA where there is evidence of both a disruption of standard breathing patterns during sleep, and symptoms such as excessive sleepiness in the daytime. OSAS occurs in approximately a quarter of those with OSA [25, 26]. Within the upper airway, the pharynx, particularly the oropharynx and hypopharynx, is the region where most obstructive processes leading to OSAS are found [27]. It is characterized by episodes of partial or complete obstruction of the upper airway during sleep, interrupting (apnea) or reducing (hypopnea) the flow of air, followed by brief awakening that leads to the restoration of upper airway permeability. The descriptions may eventually become redundant in the context of rapid technological advances in breathing measurement and other signal acquisition [28].

OSAS prevalence is supposed to rise with the present obesity epidemic. If not treated, it is related to significant morbidities such as growth collapse, endothelial dysfunction, neurocognitive impairment, and pulmonary and systemic hypertension [29].

OSAS during infancy results in significant physical and neuropsychomotor disorders. Therefore, it must be recognized and treated as soon as possible to prevent or mitigate the chronic problems associated with OSA, harmful to child development. Adenoidectomy and, in some circumstances, continuous positive airway pressure (CPAP) have been the chosen therapies for OSAS in pediatric patients, but they are unsuccessful in ultimately improving the condition. RME in kids with OSAS seems a successful cure for this condition [5, 30, 31].

The dentist's role is pivotal in children when identified with OSA; initiating dental therapies in the course of growth can aid patients, protecting them from malocclusion, and intervening in dentofacial structural development can help escape therapies such as CPAP and different surgeries. Proper evaluation and treatment may avoid compromised quality of life, delays in treatment, morbidity, and, in some cases, mortality [32].

RME treatment positively affected kids with chronic snoring and OSA, producing growth of the nasal cavity and nasopharyngeal airway volume, with enlargement of the maxillary and nasal osseous size. Enlarged nasal width at the posterior nasal spine (PNS) plane improved nasopharyngeal volume. The enlargement of the maxillary width is directly correlated with the increase in respiratory tract volume, resulting in

functional enhancement. RME treatment may reestablish and enhance a regular nasal airflow with the disappearance of OSA [33].

A better apnea-hypopnea index and lower O2 saturation were observed in OSA children treated with RME [34]. As indicated by improvement in oximetric parameters, RME would appear effective for treating slight or moderate OSA. It might be efficacious as a coadjuvant treatment to adenotonsillectomy (AT) in severe situations of pediatric patients with maxillary constriction [35].

OSA can lead, if left untreated, to severe medical complications, growth disorders, behavioral changes, and reduced quality of life. Synergy allows pediatric OSA detection, diagnosis, and treatment in an interactive and collaborative approach between ENT, orthodontists, pediatric dentists, pneumo-allergologists, sleep doctors, endocrinologists, speech-language pathologists, and myo-functional orofacial therapists to improve the short, mid, and long-term results [36].

OSAS is associated with neurobehavioral and cardiovascular abnormalities, growth, and inflammation. The treatment results in enhancements in attention, behavior, and likely improvement in cognitive skills [37]. RME can be a helpful methodology in pediatric patients with OSAS and malocclusion, as the effects of such treatment persist 24 months after the end of treatment [38].

Determining apnea-hypopnea index (AHI) per hour of sleep is essential. The greater the index, the more serious the OSA is. The onset of anomaly is 1.5AHI/h for children and 5AHI/h for adults. This syndrome has consequences far from negligible, potentially affecting mood problems, learning disabilities, growth abnormalities, and delayed neurocognitive development; it can even affect metabolism [39].

Adenotonsillar hypertrophy, in children, continues the main anatomical risk factor of OSA. AT and orthodontic treatment were more successful together than separately to cure OSA in children [40]. After undergoing both treatments, there was a more significant reduction in AHI and respiratory disturbance index and a major increase in the lowest O2 saturation and the O2 desaturation index [41].

RME devices reduce AHI in pediatric patients with OSAS making RME therapy a correct alternative treatment decision for these patients [42, 43].

RME has positive effects on nose breathing, natural head position, OSAS, nocturnal enuresis, and conductive hearing loss. RME can be considered the last treatment choice for those with normal occlusion when other possible interventions in nose breathing, nocturnal enuresis, OSAS, and conductive hearing loss have been unsuccessful [44].

Repetitive hypoxia seen in obstructive sleep apnea syndrome (OSAS) may affect bone metabolism, increasing the risk for secondary osteoporosis [45].

### **5. Down syndrome**

In Trisomy 21, the rate of otolaryngologic infection (otitis media, amygdalitis, and adenoiditis) decreased significantly before and after RME when compared to controls, regarding breathing obstruction symptoms (p < 0.01), audiometric and tympanometric progress, and various factors considered by speech pathologists such as articulation of speech sounds and tongue mobility (p < 0.01). RME offers a considerable decrease in upper airway obstruction, hearing loss, and enhanced tongue mobility and articulation in pediatric patients [46]. RME results in decreased hearing loss, the annual rate of ENT infections, parentally considered symptoms of upper airway obstruction, and enhanced articulation, tongue mobility, and intelligibility. Breaking the cycle of mouth breathing and growing the area for nasal ventilation may deliver an answer for some respiratory

*Upper Airway Expansion in Disabled Children DOI: http://dx.doi.org/10.5772/intechopen.102830*

issues, a decrease of tongue projection and drooling, as well as the high incidence of repeating respiratory infections and the high rates of crossbites and compression. The parents relate that RME produces an esthetic improvement. By putting the tongue in its natural place, speech is enhanced, thus enabling integration into society, because of the higher esthetics and self-confidence of the child. This appliance should be part of the recommendation to parents' organizations of children who have Trisomy 21. These outcomes are possibly associated with enlarged oronasal space due to RME [47].

After the expansion of palatal suture by RME, conductive hearing impairment enhancement was due to the renovated normal function of the openings of the auditory tubes [48].
