In Dento Facial Deformities (D.F.D.) the maxilla and the mandible are not in correct position,or chin and angles need for correction.
The treatment of these deformities requires integrated orthodontic orthopedics and surgical approaches. D.F.D. depend on genetic and/or teratogenic factors for the congenital forms.
Environmental factors (i.e “thumb sucking”) are also suggested. In some cases the deformity is a trauma sequelae. D.F.D. can be classified as follows:
Class II:
– mandibular deficiency
– vertical excess maxillary
– vertical excess maxillary and mandibular deficiency
Class III:
– mandibular prognathism
– maxillary deficiency
– maxillary deficiency and mandibular prognathism “Open bite” can be associated.
The treatment must be systematic and the patient evaluated by clinical analysis of facial features supported by photos, models and cephalometric analysis. After these studies, basic orthodontic treatment and surgery can be planned.
Class II D.F.D. secondary to mandibular deficiency require: A) orthodontics to reduce the dental compensations (i.e. the non correct positions). It is necessary to prepare dental arch bars for surgery. B) Mandibular advancement with or without advancement genioplasty is treatment of choice.
After intraoral incisions, the lower jaw can be osteotomized and repositioned on the basis of the pre-operative planning on VTO and model surgery, until correct position of the dental arches is achieved. When vertical maxillary excess is associated with “gummy smile”, resection with upper repositioning of the maxilla, (maxillary impaction) and mandibular advancement is required.
Class III D.F.D. secondary to mandibular prognathism: the goal of orthodontic treatment is to eliminate dental compensations.
Surgical approach include: -mandibular sagittal splitting with set back.
Adjunctive surgical and aesthetic procedures could be reduction or advancement genioplasty, submental liposuction etc..
Class III D.F.D. secondary to maxillary deficiency are treated by Le Fort I maxillary advancement combined if necessary with correction of the vertical and /or transverse maxillary deficiency .
In Class III combined, simultaneous maxillary advancement and mandibular setback are required if secondary to maxillary deficiency and mandibular prognathism.
The osteotomies of maxilla and mandible allow their repositioning in order to eliminate the dentofacial deformity with recovering of function, morphology, occlusion.
FACIAL LOWER THIRD AUGMENTATION -REDUCTION and MANDIBULAR ANGLE MODIFICATION
Generally an oval face is preferred by women. Instead a fuller augmented gonial angle and a well defined chin area portray a look of masculinity and a stronger face, often requested and preferred by men.
Lower third sagittal augmentation/modification:
The chin can be augmented, reduced, elongated, and widened with different types of osteotomies (bony cuts).
Lower third transversal augmentation:
Mandibular angles can be augmented with the help of different types of biomaterials of different angular shapes.
All these operations are performed intraorally, without any external scars.
Today, with the advent of additive manufacturing, more precise customized shaping and implants can be better adapted to the mandibular bone.
Lower third transversal reduction:
People from Asian countries prefer the contrary: a more rounded lower face with mandibular angle resection and /or zygomatic reduction/reshaping.