Textbook Reading Erika 1112017022 The Goal of Treatment and Camouflage

Orthodontic and Dentofacial Orthopedic Treatment - Rakosi & Graber
The Goal of Treatment and Camouflage
Diagnosis has generally been based on an ideal occlusion paradigm. This concept is
not evidence-based because the arbitrary ideal occlusion is the exception and not the
rule. The “old glory” skull in the Angle textbook (Angle 1907) (Fig. 1.26) is no longer
the realistic goal of orthodontic treatment. Achieving a stable, ideal occlusion for all
patients is unrealistic. This is an articulator concept that may serve well for artificial
dentures, but not for the living, developing, changing human being. Gnathology has
been called by Lysle Johnston “the science of how articulators chew.” Myriad
functional variabilities and responses cannot be sufficiently replicated on a mechanical
reproduction of the temporomandibular joint and upper and lower dentitions. It is a
fallacy to assume that mandibular opening is a purely rotary action via a hinge axis
movement in the glenoid fossa. That is an outmoded mechanical prosthetic concept.
The goal must individualized and differentiated. It must be an individualized,
achievable optimum, a balance of structural, neuromuscular, and esthetic outcomes that
will be stable and will most benefit the individual patient. Careful examination of the
patient periodically during active orthodontic treatment provides the best answer for
both the patient and the clinician. Altogether too many orthodontists still ignore the
role of the draping soft tissue as they expand dental arches off basal bone and into
muscle forces. An important question in assessing the goal for treatment is the threedimensional status and relationship of the supporting components of the dentofacial
complex. Are the skeletal and neuromuscular components balanced before we start?
We should try to maintain that balance. If they are unbalanced, it should be our goal to
establish a harmonious dentofacial relationship when we have completed
mechanotherapy. Figure 1.27 illustrates a balanced skeletal and neuromuscular frame.
Dentoalveolar changes, i.e. tooth movement, should strive to maintain that balance.
Fig. 1.26 The alveolodental portion of the classical Angle “Old Glory” skull,
demonstrating long axis inclinations.
In a dysplastic relationship of skeletal and neuromuscular components, growth
guidance, growth enhancement, inhibition, or directional change are usually indicated
(Fig. 1.28). In some cases, this is not possible, especially in the permanent or adult
dentition, and camouflage treatment is necessary. Too often, we have tried to fit a
normal occlusion onto an abnormal maxillomandibular relationship. The unstable
results and iatrogenic consequences reflect an unrealistic diagnostic study and
treatment goal. In severe adult cases, where not even camouflage is possible, a
combined orthognathic surgical approach may be necessary. With distraction
osteogenesis, this is now an easier and potentially less iatrogenic approach that the
traditional sagittal split, LeFort I, and Le- Fort II orthognathic surgery alternatives (see
Chapter 17) Before treatment is started, a thorough diagnostic regimen must be used to
decide whether it is possible to attain an achievable optimum via camouflage or
whether it is necessary to resort to surgery. Camouflage and presurgical orthodontics
require completely different treatment procedures. In camouflage, the compensation
consists mostly in tipping of the incisors. Presurgically the incisors must be uprighted
by the orthodontist. For camouflage, much depends on the position and inclination of
the incisors and jaw bases and the possibility of stable change as we produce an
esthetically more acceptable result without surgical assistance. Figure 1.29 illustrates
possible camouflage of a Class II relationship by lingual tipping of the upper incisors
and labial tipping of the lower incisors. The position and inclination of the jaw bases
are important considerations, depending on the facial pattern. Besides the inclination
of the mandible (mandibular and occlusal planes), the inclination of the maxillary base
must also be assessed (Fig. 1.30).
Depending on the combination of these inclinations, there are various possibilities for
treatment: e.g., convergent rotation of the jaw bases (Fig. 1.31); horizontal growth
pattern, with retroinclination of the maxilla; severe skeletal deep overbite. Figure 1.32
illustrates diverging rotation: vertical growth pattern and anteinclination of the maxilla;
severe skeletal open bite malocclusion. Prognosis is poor in such patients. The patient
must be informed in advance. Figure 1.33 illustrates jaw growth rotation in the same
cranial direction. For example, a horizontal pattern with anteinclination of the maxilla;
compensated skeletal deep overbite; the anteinclination is opening the bite. Figure 1.34
shows rotation in the same direction in caudal or downward and backward rotation
compensated open bite. The tracing shows a vertical growth pattern with
retroinclination of the maxilla; compensated skeletal open bite; the retroinclination is
closing the bite. Study these illustrations carefully and be aware of the challenges to
orthodontic, orthopedic, and orthognathic services. If the patient is not informed in
advance (i.e., informed consent), the potential for litigation is greatly increased.