Decision of surgical first approach depends on the severity of skeletal malocclusion (class II or class III) and the time constraint. Based on the pre-treatment Incisor inclinations in Moderate-Severe class II or class III, I assess the amount of dental de-compensation required through an extraction/non-extraction approach.I prefer non-extraction approach in a skeletal class III and extraction in class II cases. Incisor inclination influences the outcome of any orthognathic surgical procedure.

Dental compensation is extremely important before going for orthognathic surgery . Cases i have treated with dental compensation usually attain skeletal class 1 relations while cases i have seen without dental compensation usually retain their original skeletal pattern in a less severe from .With dental decompensation you get better result in terms of occlusion too as nothing is based on assumption .

Criteria for dental decompensation

cases in which dental compensation to great to effect your future skeletal pattern

Case of crowding where you extract anyway either pre or post surgically .

cases with impacted teeth .

Cases with sub division dental relation in the absence of dental deformity .

High angle case .where leveling cos presurgically

Surgical first cases .

Though surgeons do all types of cases but i following cases should be taken

Cases with well aligned upper and lower arch with less severe dental compensation . Even than optimum skeletal relation wont be attained .

Cases where surgery will help future relive of crowding . Sarpe and lower jaw distraction osteogenesis .

genioplasty ,

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Decompensation is a step which will be done at some point in every surgical case for achieving optimum result which is stable. In surgery first cases, the decompensation is done in the post surgical phase, in conventional cases, the decompensation is done pre surgically. Every surgical orthodontic case requires decompensation to remove the compensatory mechanisms that have come int0o play.

What are the criteria ? This is a bit tricky. Some simple cases can be treated with surgery first and orthodontics later. They will still require the post surgical tooth movements which will essentially correct the compensations that are present in the arches! Surgery first cases are to be chosen carefully. Those will be cases which have an almost well aligned arch and it is possible to have a atleast a stable three point contact for the arches to achieve a stable reference during surgery. The result is dependent on the surgeon-orthodontist team as a whole. During the post surgical phase, the orthodontist can settle the occlusion. The treatment is quick as the effect of Acceleration Phenomenon comes into play in the post surgical phase as the jaws are actively remodelling in the post surgical phase which helps in faster teeth alignment. Everything is ideal and works in favour of the patient for best results .... atleast itheory. But in practical terms, the main problem is three fold - one there are very few orthodontists who are prepared to take a surgery first case (as it kind of defies the traditional outlook in surgical orthodontics!) and two - there are very few surgeons who are prepared to take the case as they fear a lack of support from the orthodontic colleagues. And the most important third limitation is the difficulty in assessing which cases are best treated surgically first ...

Severe Class III cases and Class II cases can be very disfiguring. Decompensation will aggravate the disfigurement to the point of severe social embarassment for hte patient. This becomes more important for teenagers who are considered ready for surgery only in their late teens earliest or later in some cases! In those cases, partial surgical treatment can be done with supportive orthodontics keeping in mind that furtehr surgeries may be required at a later stage again. If the patient and the parents are ready to undergo such a hassle of two surgeries and prolonged treatment time, it may be considered. But the cost factor is a major inhibiting issue in such a treatment. Also, surgeries invariably result in scar tissues which behave differently than the healthy oral mucosa and there can be secondary issues in such a treatment plan.

To summarise, decompensation IS an essential step in EVERY orthognathic surgical case and this IS the most important step that helps achieve post surgical stability as well as esthetics. In surgiery first-orthodontics later cases, the surgeon-orthodontist team must collaborate to anticipate the jaw movements required and it is not that easy to decipher the end result inspite of the advances in treatment planning available today.

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Dr. Akilesh. R

India

All severe malocclusions have compensations present. Most should be decompensated before surgery. The only ones I can think of to correct later may be a severe curve of spee in an over closed deep bite where you want to increase the lower face height and an anterior open bite with a 2 step occlusion where the surgeon may do a 3 or 5 price maxillary osteotomy.