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The term dentofacial deformity refers to significant deviations from normal proportions of the maxillomandibular complex that also negatively affect the relationship of the teeth within each arch and the relationship of the arches with one another (occlusion).2,4,5,8,11,14,15,17,18,21,22,25,27,31,36,37,40,52,54 The affected individual will have varied degrees of compromise in head and neck functions related to breathing, swallowing, speech articulation, chewing, and lip closure/posture. Effects on the temporomandibular joints, the periodontium, and the teeth themselves may also occur.^{24,25,28,33,34,38,55} The presenting facial disproportion will, in general, have at least some negative effects on psychosocial health.^16,39,56,57

Racial variations with regard to the incidence of facial dysmorphology and the resulting malocclusion are also known to occur.59,64 Definitions of acceptable levels of deviation from normal continue to be questioned by both clinicians and patients.^{7,26,30,32,35,58,61,62} Over the years, the National Center for Health Statistics has collected data and the Research Council has held multidisciplinary conferences to focus attention on these issues.^{6,12,19,20,29,41-51,53,63}

Surgery to reposition the jaws (i.e., an orthognathic procedure) as part of an interdisciplinary approach is often recommended to manage the related skeletal, dental, and soft-tissue dysfunctions and concerns.3,13,23,60,66 Speech therapy, dental work, orthodontics, and surgical procedures alone are generally inadequate as isolated treatment modalities.

A dental clinician who is asked to evaluate the affected individual must ask himself or herself, “Are the problems too severe to be most effectively managed with orthodontics and dentistry alone?” A cosmetic surgeon who evaluates the same patient must ask himself or herself, “Will limited soft-tissue or augmentation procedures alone be sufficient to properly manage the presenting dysmorphology and to address functional aspects?”

If the discrepancy in the size or position of the jaws as they relate to each other and to the upper facial skeleton results in significant facial disproportion and also negatively affects certain head and neck functions (e.g., speech, swallowing, chewing, lip closure and posture, breathing), then it should not be ignored. It would be misguided to consider orthodontics alone to alter the occlusion without fully informing the patient and his or her family of the preferred biologic approach to management (i.e., orthodontics and jaw surgery). Likewise, it would be avoiding the obvious for the cosmetic surgeon to recommend either soft-tissue aesthetic or skeletal contour procedures without discussion of the presenting malocclusion, airway dysfunction, and overall facial disproportion. The treatment recommended to the patient and his or her family should not be limited by the skill set of the initial consulting clinician.

Facial disproportion observed in a child may at times be self-correcting. For example, apparent mandibular deficiency that is present before the pubertal growth spurt may normalize. In some cases, the maxilla or mandible may be induced to grow a few millimeters, more or less, through dentofacial orthopedics. However, major transformation of the jaws with the use of growth-modification techniques cannot be expected. Proffit has pointed out that, even with the well-intended aim of dentofacial orthopedics to alter jaw growth, as a result of anchorage requirements and biologic realities coupled with the practical desire of the orthodontist to “correct the occlusion,” the treatment generally results in the displacement of the teeth in the direction of correcting the occlusion rather than the jaw relationships.⁵³ The term dental compensation for the skeletal discrepancy is universally understood to explain this treatment approach. Orthodontic-introduced dental compensation for the occlusion will hinder the eventual skeletal (orthognathic) correction if this is later required or requested.

Informed consent from the patient or his or her family is strongly recommended before embarking on a compromised treatment plan. For example, if a child is recognized to have an underdeveloped mandible with a Class II malocclusion and standard growth modification is attempted, it may be difficult for the orthodontist to prevent at least some retraction of the upper incisors and the forward displacement of the lower teeth. This may result in an “improved” occlusion, but it may also potentially involve long-term negative effects on periodontal health (e.g., labial cortical bone stripping), the airway (e.g., retroglossal obstruction), and facial aesthetics (e.g., a weak profile).39,56,57 It also compromises the option of an orthognathic correction with the need to first “undo” the dental compensations through “redo” orthodontics (Fig. 3-1).

In the growing child who presents with a Class II malocclusion pattern, an active treatment approach is often offered by the orthodontist. This approach may attempt to alter jaw growth and to correct the occlusion by means of the following: (1) functional appliance use (e.g., Frankel, Twinblocks) to stimulate sagittal growth of the mandible; (2) the possible extraction of maxillary premolars with orthodontic incisor retraction; (3) the use of headgear to restrain maxillary sagittal growth; and (4) the orthodontic forward displacement of the lower anterior teeth (Fig. 3-2). With the use of this approach, favorable facial results will be seen in only a very specific patient subgroup that includes those patients with true maxillary dental protrusion and a limited degree of mandibular retrusion. In these cases, the extraction of maxillary premolars with the retraction of the incisors to a corrected inclination in combination with the minimal forward displacement of the lower teeth may result in both favorable occlusion and acceptable facial aesthetics.

For the experienced surgeon and orthodontist, the accurate diagnosis of a dentofacial deformity will usually be clear after the initial examination and a review of standard records. A favorable correction through the effective orthodontic alignment of the teeth in combination with the surgical repositioning of the jaw(s) will be the preferred approach.

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Binder Syndrome: Evaluation and Treatment Aesthetic Alteration of the Soft Tissues of the Neck and Lower Face: Evaluation and Surgery Long Face Growth Patterns: Maxillary Vertical Excess with Mandibular Deformity Primary Mandibular Deficiency Growth Patterns with or without Maxillary Arch Constriction Cleft–Orthognathic Surgery: The Unilateral Cleft Lip and Palate Deformity Sequencing of Orthognathic Procedures: Step-by-Step Approach

Orthognathic Surgery Principles and Practice