What is orthognathic surgery?
Dentofacial deformity is a disharmony between the maxilla and the mandible that causes a malocclusion (bite alterations) and a facial aesthetic alteration.
Orthognathic surgery is the surgery in charge of surgically solving this type of dentofacial deformities, recovering the correct position of the jaws in the three axes of space. In this way, it allows the patient to recover a good occlusion (bite) and optimize their facial features to regain facial harmony (beauty). Therefore, the objective of orthognathic surgery will include both restoring correct masticatory function and recovering facial esthetics altered by the malposition of the jaw bones.
In which cases is orthognathic surgery useful?
Orthognathic surgery will be useful in all cases in which we find facial aesthetic alterations and associated occlusal alterations. There will also be cases in which the facial esthetics are not very altered, but in which orthodontics is insufficient to achieve a correct bite, because the dental movements would be excessive. In these cases, it will be necessary to evaluate whether modifying the position of the bones will restore masticatory function and improve the patient’s esthetics.
There will also be other problems in which the occlusion (bite) is correct, but for some reason the position of the bones is not good and alters the facial esthetics. When this happens, the altered features could also be improved with some minor osteotomies, such as a mentoplasty.
Lately, it is being indicated in sleep apnea disorders for functional reasons, with advancement of the jaws to increase the airway and making it possible to dispense with nocturnal ventilation devices during sleep (CPAP). These would be the cases in which these procedures are most indicated.
What pathologies does it correct?
Mainly, what we have previously defined as dentofacial deformities, correcting the facial esthetic component and the occlusal component at the dental level. For this reason, it corrects bite alterations that secondarily cause jaw joint alterations. In these cases, by correcting the way of chewing in a more stable and balanced way, we can improve the functional alterations of the temporomandibular joint (TMJ) and the muscular pain associated with it, in the form of headaches due to contractures of the masticatory muscles.
On the other hand, it also acts at the level of airway alterations due to malposition of the jaws. A delayed position of the jaw bones decreases the respiratory space (upper airway), producing sleep apneas at night. This pathology leads to an increase in cardiac functional overload due to lack of oxygenation of the blood and daytime sleepiness with headaches, due to poor rest at night. Correction of the altered position of these jaws will improve the upper airway breathing space, in turn improving airflow when the patient is lying down. This will allow for better rest and a decrease in cardiovascular risk.
How are these surgeries performed?
This type of surgery has evolved dramatically over the last 30 years. Technological development (3D software, piezoelectric scalpels, digital printing, more powerful and less aggressive motors…) has allowed us to move from two-dimensional to three-dimensional planning, gaining above all in precision. It has also allowed us to be faster and more precise in the operating room, in addition to being able to plan the surgeries virtually and prepare positioning guides by digital impression (CAD-CAM), which position the bones in the three-dimensional position chosen in the virtual surgery on our computer.
It is an intervention that requires a previous orthodontic treatment aimed at placing the orthodontic teeth in an adequate position within each jaw, thus correcting dental compensations that the patient brings with him/her when he/she comes to our office. Once the teeth have been correctly arranged in each arch, following previously studied guidelines, the patient is operated on by cutting the bones in studied areas to avoid altering vascular and nervous structures. Finally, guided by splints previously designed in the computer and printed in 3D, we place the bones in the studied position to optimize the bite and achieve the most harmonious face possible.
After 3-4 weeks of recovery, the patient can gradually return to his or her life, with certain dietary care. At 4-6 months after the last orthodontic corrections the case will be finished.