The search of etiological factors is a fundamental step in the diagnosis. The success of orthodontic treatment is essentially based on the quality of the clinical observation; any cause related to malocclusion must be identified and analyzed. The acquired knowledge and clinical experience, then, will allow the best choice of the therapeutic method. The mechanisms of facial development and growth are numerous and strongly nested; thus, it is difficult to identify all the etiological factors involved in orthodontic malocclusions, but we can determine a large number among them and avoid their impact and so, many anomalies. The mistake would be to not suppress them or act late. Anomalies may appear, or become worse if they already exist, or relapse after orthodontic treatment.
The orthodontic literature attaches great importance to etiopathogeny, and the various factors involved in the appearance of anomalies [4,5]. These have been the subject of multiple searches and classifications. This led to establishing general and local causes of orthodontic anomalies. Factors are considered intrinsic or extrinsic. It may be heredity, congenitalcauses, predisposing metabolic disease, nutritive deficiency, factors related to the muscular environment, the orofacial functions disorders (improper deglutition, speech defects, abnormal chewing), and the presence of harmful habits (thumb or lip sucking) [6,7] or dental causes (premature dental contact, early loss of primary teeth, trauma).
It is important to note that most orthodontic anomalies  have multifactorial etiologies and that it is difficult to distinguish between the part that goes with predeterminism and that related to the environment. Moreover, it is recognized that neuromuscular behavior may be genetic in origin and that hereditary abnormalities may cause functional disturbances. The prognosis is naturally more reserved when a hereditary etiology is implicated. The practitioner must take this into account at the time of the therapeutic decision.
While it is difficult to act on certain predetermined etiological factors, many can be improved. The goal is to prevent the onset or aggravation of abnormalities and recurrence after treatment. For this, we can use simple methods and appliances:
a. dental caries screening and endodontic care of temporary dentition to ensure the balanced development of the dentoalveolar arches;
b. maintaining the space in case of premature loss of the primary teeth to avoid the loss of space and dental crowding [9,10];
c. unlocking the occlusion to allow growth to express
itself normally in case of deep bite, anterior or lateral crossbite;
d. treatment of breathings problems (buccal breathing)
by the otolaryngologist and the orthodontist;
e. functional education of swallowing and chewing,
suppression of harmful habits to avoid their impact in the
onset of bone or dentoalveolar anomalies and prevent their
recurrence after treatment ;
f. suppression of possible obstacles (premature dental
contact, hypertrophic labial frenum, short lingual frenum,
supernumerary teeth, persistent temporary teeth).
The essential concern of the orthodontist is the success of the
treatment; the etiological analysis is a crucial step in establishing
the diagnosis. It is possible to avoid long and difficult care for
both the patient and the practitioner by intervening early and
effectively on the causes of certain orthodontic abnormalities
knowing that the association; etiological treatment and
treatment of the anomaly is possible. The results remain stable
with a reduced risk of recurrence, the approach depends
however on the patient’s cooperation and the isolated or nonisolated,
primary or secondary nature of the etiology involved.