There is much controversy regarding the timing of surgical correction of malocclusions. Many colleagues are reluctant to surgically correct developmental anomalies in the jaws before facial growth is complete. Waiting until skeletal growth is complete is justified for two reasons:

1.

The surgical procedures required to correct the skeletal malformation may adversely affect subsequent growth [3]

2.

Facial skeletal growth continues postoperatively, which could significantly affect the outcome of any surgery performed [4,5,6,7].

Conflicting results continue to be published, both advocating and discouraging an early surgical approach [8,9,10,11,12,13,14]. However, treating these patients with jaw abnormalities during their growth poses a challenging problem for both orthodontists and maxillofacial surgeons. One of the problems is the uncertain postoperative growth tendency, as there is no concrete consensus regarding the age limits for orthodontic or maxillofacial therapies [15]. The most compelling reason for early surgical correction before facial growth is finished is often the psychosocial component of the growing patient. Many children with severe jaw anomalies have problems being accepted by their peers, because facial appearance is an important factor in determining social relationships and affects the psychosocial perception of the child or adolescent [16, 17]. Therefore, early surgery during growth may be warranted and should be seriously considered to avoid negative psychological and/or psychosocial effects [16, 18, 19]. The potential benefits of early surgical correction of severe malocclusions also include a shorter treatment time, since no orthodontic phase treatment [20] is performed, and an increased healing potential [21]. Analysis of the growth rate and growth vector can be challenging, but it is necessary because the dysgrowth of the jaws often occurs in one but also in several dimensions. In general, female have completed about 98% of facial growth by the age of 15 and male by about the age of 17 [22, 23]. An understanding of facial growth tendencies and the specific anatomical face types (e.g., brachycephalic, normocephalic, dolichocephalic) provides important information about subsequent growth. Evaluation of the patient's medical and family history, as well as clinical and radiological examinations, is helpful in identifying growth disorders in the jaws [24].

Factors that can significantly affect the direction and rate of maxillary growth include genetics, developmental conditions, hormonal stimulants, and obstruction of the nasal or oropharyngeal airways [24,25,26,27,28,29,30,31]. The surgical management of the growing patient with maxillary anomalies continues to be the subject of much controversy.

The most common surgical procedure in the upper jaw to correct malocclusions is the Le Fort 1 osteotomy [24].

During this surgical procedure, the maxilla is separated from its bony cranial pillars (apertura piriformis, crista zygomaticoalveolaris, fissura pterygomaxillaris) and the nasal septum.

This surgical separation (referred to as a “down fracture” of the maxilla) effectively arrests further anteroposterior growth of the maxilla [32, 33].

Thus, if surgery is performed during the growing years, postoperative recurrence resulting in skeletal class III could occur if the mandible continues to grow normally.

If an early operation is nevertheless indicated for functional, esthetic and psychosocial reasons, a certain amount of overcorrection must be taken into account in the Le Fort I osteotomy of the maxilla so that the mandible, which is still growing, can develop and adjust properly in a natural way.

If this operation is performed during growth, the patients and their families must be fully informed that further operation is likely to be necessary at a later date [34]. Alternatively, the so-called "horseshoe osteotomy" (complete dentoalveolar osteotomy) of the upper jaw is under discussion. This osteotomy technique maintains the septal and vomeric connection in the maxilla because only the dentoalveolar mobilization is performed [24].

It is important to keep in mind that in patients who require maxillary advancement, there is insufficient maxillary growth preoperatively and there is no further anteroposterior growth, vertical maxillary growth, after the Le Fort I osteotomy, however, continues at the same preoperative rate postoperatively [33, 35, 36] and the mandible also continues to grow at the preoperative growth rate, which could again result in a Class III occlusal relationship [24].

However, severe functional or psychosocial factors may indicate earlier treatment. Both osteotomy procedures can technically be carried out in the first decade of life if there is sufficient space above the root tips of the developing permanent teeth or tooth germs to carry out the osteotomy and to carry out a sufficient osteosynthesis. Although vertical growth of the maxilla is unlikely to be affected by this procedure, damage to the developing tooth germs and roots can result in dentoosseous ankylosis and localized impairment of dentoalveolar growth [24].

ENT aspects

The Eustachian tube protects against secretion, germ ascension and sound pressure from the nasopharynx, acts as a drain and serves to equalize pressure in both directions so that the eardrum and the sound conduction apparatus can vibrate optimally. Tubal dysfunction has an incidence of about 1% in adults and almost 40% in children. Symptoms are often nonspecific. In children, adenoid vegetations are often the cause of obstructive tubal dysfunction. In the case of the obstructive form, nasal sprays containing cortisone and the regular implementation of the Valsalva maneuver as well as tube dilatation with the Bielefeld balloon catheter are used therapeutically [37]. The typical symptoms of chronic obstructive tubal dysfunction are a feeling of pressure in the ears, aggravated by atmospheric pressure fluctuations, and difficulty in performing the Valsalva maneuver. Symptoms are often persistent and affected patients have long medical histories, which may begin in childhood. Long-lasting obstruction of the tube can lead to tympanic effusion and tympanic membrane retraction, often associated with a hearing loss (usually conductive hearing loss), and plays a crucial role in the pathogenesis of cholesteatoma [38]. Since patients with obstructive tube ventilation disorders tend to develop middle ear infections, they often suffer from the typical (late) consequences of recurrent or chronic inflammation of the middle ear [37]. Obstructive tube ventilation disorders are a common phenomenon in childhood. The predominant part is caused by adenoid vegetations. These constrict the torus tubarius and often sustain a local inflammatory reaction with mucosal swelling. In addition, the structure and the angle of inclination of the Eustachian tube are still different from that in adults up to about the age of 7: The cartilaginous part is larger, and the angle of ascent is flatter. The most important consequences of this tube dysfunction are serous to mucous tympanic effusions and recurrent otitis media. Favoring the development of cholesteatomas and adhesive processes is also discussed [37, 39]. The standard therapy consists of adenotomy and paracentesis, if necessary tympanic drainage. In the case of recurrent tympanic effusions and middle ear infections without recurrent adenoids or if the symptoms recur after tympanic drainage, balloon dilatation of the Eustachian tube can be considered as a second-line therapy [37, 39].