the nasal cavity shows the greatest expansion with traditional RPE, with the posterior having less develop-ment, creating a pie-shaped expan-sion pattern at the palatal suture if sutural separation occurs. Appliances that are non-tooth-borne or non-fixed, such as remov-able acrylic appliances with wire retention and aligners, place forces on the crowns of the teeth only. With slow activation protocols, they will only achieve dental tipping without significant palatal suture separation. Despite claims of skeletal develop-ment, CBCT imaging does not support consistent expansion of the apical base or nasal airway dimen-sions with such appliances. What is consistently observed in the coronal plane on CBCT is dental tipping, which is unfavorable for esthetics and periodontal stability and has high relapse potential as soon as retention is discontinued. In addition, these patients will have no improve-ment in the transverse dimension of the nasal cavity and therefore experi-ence no improvement in nasal airway resistance and are much less likely to achieve passive nasal breathing and spontaneous lip seal. In today's orthopedic approach to orthodontic treatment, we must step back from the old assumption that dental crowding is a specific pathol-ogy. Instead, we should consider that dental crowding is the result of pathologic growth and development of the maxilla and mandible. Histori-cal anthropological studies show that dental arches have remained broad throughout human history, with adequate room for the dentition. It is only in the modern era that dental arches are developing with insuffi-cient transverse dimensions to house the normal human dentition. As dentists, we have observed and measured the dental arch widths with indexes such as the Schwarz, Ponts, SIM, etc., but these approaches only measure the transverse dimensions of the crown portion of the teeth, not evaluating the root position or angu-lation or the dimensions of the supporting alveolar bone or apical base of the maxilla or supporting body of the mandible. Additionally, the traditional orthodontic imaging techniques (panoramic and lateral cephalometric radiographs) do not image these relationships, so they have remained largely unnoticed until the advent of CBCT imaging allowing detailed evaluation of the angulations of posterior teeth in the coronal plane. Thus, in patients with a narrow maxillary dental arch, the apical base and nasal airway housing are affected. The mandibular dentition is frequently seen to be tipping lingually as a compensation for the maxillary transverse deficiency. With-out adequate skeletal dimensions, nasal airflow will be restricted, caus-ing compensatory mouth breathing. Appliances that result in dental-alveolar movements, such as dental tipping or transportation of teeth through the buccal cortical plate, will increase tongue space but not result in skeletal development of the nasal airway. These patients have a high potential for not achieving passive nasal breathing and will remain compensatory mouth breathers. However, patients of all ages commonly convert to passive nasal breathing as a result of maxil-lary skeletal expansion with signifi-cant separation of the midpalatal suture and enhancement of the transverse nasal cavity dimensions. Therefore, our goal for patients of all ages is to achieve patent, passive nasal breathing and resting lip seal as quickly as possible to enhance normal facial growth and develop-ment and sleep while also providing enough room to house the primary and mixed dentition. In essence, we have applied the treatment concepts for airway-compromised adolescent and adult patients to the young child suffering the same disorder for the same reasons. Prevalence of Pediatric Sleep-Disordered Breathing In today's society, the prevalence of pediatric sleep-disordered breathing is rampant, with many children suffer-ing. This is often not screened for in either medical or dental practices. The F.A.I.R.E.S.T. survey, developed by Dr. Soroush Zaghi and the Breathe Institute, is a useful tool for screening children for the potential for pediatric sleep-disordered breathing. This survey consists of 25 questions that serve as red-flag indicators for pedi-atric sleep-disordered breathing, in addition to six dental-facial-oral exam metrics that reflect relative risk. In our practice, we take a F.A.I.R.E.S.T. evaluation prior to treat-ment and after treatment is completed. The goal is to optimize the sleep experience for children, establish patent nasal breathing and a passive lip seal, and resolve the F.A.I.R.E.S.T. evaluation to normalcy. When the F.A.I.R.E.S.T. form has not cleared after orthodontic intervention and numer-ous signs of pediatric sleep-disordered breathing remain, the practitioner needs to look further into pathologies that would cause upper airway resis-tance or obstruction, such as turbinate hypertrophy secondary to allergies, septal deviation, adenoid hypertrophy, palatine tonsil hypertrophy, lingual ankyloglossia, and evaluate the ortho-pedic position of both the maxilla and the mandible. It has been observed that children aged 3 to 5 years suffering from pedi-atric sleep-disordered breathing have many concerns, such as poor focus, hyperactivity, lethargic behavior, high sympathetic tone, poor sleep, night-time sweating, nightmares, and bedwetting. The reason to consider treating a patient aged 3 to 5 for maxillary transverse deficiency is that these patients typically suffer from pediatric sleep-disordered breathing, which affects their systemic health, including hormone dysfunction, cardiac pathology, and abnormal behaviors disruptive to their lifestyle and that of their families. In addition, rapid palatal expansion in young chil-dren has a profound effect on the sleep experience of children in this age range in addition to the benefit of creating room for the permanent incisors to erupt. The idea of using RPE in young children goes against the grain of traditional treatment techniques as historically practiced but achieves the desired goals (upper arch develop-ment, increased transverse dimension of the nasal cavity, and improved nasal breathing and sleep experience) and brings the skeletal structure toward the goal of normalcy for a orthodontics.com Summer 2026 27
Journal of the American Orthodontic Society Summer 2026: Page 27
