Tag Archives: How-To

Orthognathic Surgery : How to

Edited by : Dr. Hani Alhebshi

Orthognathic surgery is a type of surgery that is done to the jaws to correct a frank skeletal discrepancy.

The common steps in order are :

  • Pre-surgical orthodontic treatment (decompensation orthodontics).  This involves aligning the teeth on the jaws according to their basal bone , and may require extractions,  A few weeks before surgery when decompensation orthodontics is completed patient will undergo a surgical assessment and pre-planning.  This involves taking impressions, x-rays, pictures and models of the teeth as well as a face bow (jaw registration).  This will allow the surgeon to plan the movements of the jaw and the technician will be able to construct the splints required during surgery.
  • The surgery is usually performed under general anaesthetic and can take up to 3 or 5 hours to complete depending on how much jaw surgery is required.   The new position of the jaws is maintained with the use of plates and screws and on occasions these may be resorbable .  Most common surgical cuts involve : Maxillary LeFort I for maxillary impaction or advancement , Bilateral sagittal split osteotomy for mandibualr advancement or set back , and  genioplasty to either advance or set back the chin.
  • Post-surgical Orthodontic Treatment (following surgery) : Elastics are applied to the teeth to guide the new bite and the patient is put on a soft diet for 6 weeks.  During this time medications such as antibiotics, analgesics and nasal drops are often required in the first week or two after surgery.  Then elastics are removed after about six weeks and the final adjustments to teeth and bite are undertaken by the orthodontist in consultation with the surgeon.  The process can last a further three to six months depending on the complexity of the procedure.

Here are videos that shows the procedures done in different types of orthognathic surgery.

Lefort 1 Osteotomy HD

Bilateral Sagittal Split osteotomy

Orthodontic Elastics

Summarized by Dr. Hani Alhebshi …

The following information are summarized mainly from an article titled “Elastics in orthodontics: a review” by VP Singh
, PR Pokhrael , K Pariekh , DK Roy, A Singla , KP Biswas as referenced at the end of this post.

Elastics are widely used in different clinical situations.

Elastics have an internal diameter usually measured in a unit of an inch like 1/8 of inch.

The thickness of the elastic band will affect the force it delivers.As the thickness increases the force delivered increases.

rubber bands dimentions

How long should the elastics be stretched to get the desired force ?

The standard force index employed by suppliers indicates that at three times the original lumen size, elastics will exert the force stated on the package. Continue reading Orthodontic Elastics

Sequence of archwires of 2 bracket prescriptions (0.018 and 0.022 slots)

This is a general guideline of the sequence of archwires during treatment which can be modified according to the clinical situation.

( Summerized from a lecture of Dr. Zuhair Bakhsh ).

*For 0.018 x 0.025 slot brackets

Phase I (Alignment&Leveling):

1.0.014 Niti

2.0.016 Nitti
Continue reading Sequence of archwires of 2 bracket prescriptions (0.018 and 0.022 slots)