Our Summary

This research paper explores whether there’s agreement between two-dimensional (2D) and three-dimensional (3D) assessments of the position and rotation center of the mandible condyle - a part of the jawbone - and whether this information can be used in planning orthognathic surgeries, which are operations to correct conditions affecting the jaw and face.

The team looked at major databases of medical research for studies that assessed the mandibular condylar position in either 2D or 3D, with regards to its socket and rotational axis, for use in surgical planning.

However, they found that differences between the studies and uncertainties about potential biases in their methods made it impossible to determine whether 2D or 3D methods were superior in defining the rotation axis of the condyle. There was also substantial disagreement regarding the definition of how the teeth come together among different dental specialties.

Although the researchers could not reach consensus on the position of the condyle in relation to its socket, the most frequently reported rotation axis was at the back and bottom. The lack of strong scientific evidence and disagreements in dental terminology indicate a need for more scientifically rigorous studies with clearer and more transparent methods in order to standardize concepts.

Based on the evidence, they suggest that the “centric relation” - a term used to describe a specific jaw position - is not the position of the condyle when it is manipulated in the back and upward direction. Instead, this position is referred to as the “retruded contact position”, while the centric relation is the functional position of the condyle. This implies that there are two ways the teeth come together that need to be considered during the planning and execution of orthognathic surgery.

The researchers concluded that the ideal rotation axis for planning orthognathic surgery must be fixed, allow for individual differences between each condyle, and be replicable. They also suggest that 2D planning is outdated as it cannot provide all the necessary tools for accurate planning.

FAQs

  1. What is the aim of the evaluation in this orthognathic surgery study?
  2. What conclusion was made about the superiority of 2D or 3D methodology in determining the condylar rotational axis?
  3. How is the ideal axis of rotation for orthognathic surgery planning described?

Doctor’s Tip

A helpful tip a doctor might tell a patient about orthognathic surgery is to follow all pre-operative and post-operative instructions carefully to ensure a successful outcome. This may include maintaining good oral hygiene, eating a soft diet, avoiding certain activities that could impact the healing process, and attending follow-up appointments as scheduled. It is also important to communicate any concerns or questions with your healthcare provider throughout the process.

Suitable For

Patients who may be recommended orthognathic surgery typically have severe malocclusion, facial asymmetry, difficulty chewing or speaking, sleep apnea, temporomandibular joint disorders, or other issues related to the alignment of the jaw. Orthognathic surgery may be recommended by orthodontists, oral surgeons, or other dental specialists after a thorough evaluation of the patient’s condition and treatment options.

Timeline

Before orthognathic surgery:

  1. Patient undergoes a consultation with an orthodontist and maxillofacial surgeon to discuss the need for surgery.
  2. Comprehensive orthodontic evaluation and treatment planning is done to align the teeth and jaws.
  3. Pre-surgical orthodontic treatment may be necessary to prepare the teeth for surgery.
  4. Imaging studies such as X-rays, CT scans, and possibly 3D scans are taken to assess the jaw and facial structure.
  5. Virtual surgery planning is conducted to determine the optimal surgical approach and outcome.

After orthognathic surgery:

  1. The surgery is performed under general anesthesia, involving repositioning of the jaws to improve function and aesthetics.
  2. Recovery period typically involves pain management, swelling, and a liquid diet for a period of time.
  3. Post-operative orthodontic treatment is necessary to fine-tune the bite and alignment of the teeth.
  4. Regular follow-up appointments are scheduled to monitor healing and adjust the treatment plan as needed.
  5. Long-term results include improved facial harmony, function, and overall satisfaction with the treatment outcome.

What to Ask Your Doctor

Some questions a patient should ask their doctor about orthognathic surgery may include:

  1. What are the potential risks and complications associated with orthognathic surgery?
  2. How long is the recovery period after orthognathic surgery?
  3. Will I need to wear braces before or after the surgery?
  4. How will my bite and facial appearance be improved after the surgery?
  5. What type of imaging or planning is done before the surgery to ensure the best outcome?
  6. Will I need to follow a specific diet or oral care routine after the surgery?
  7. How experienced are you in performing orthognathic surgery?
  8. Can you explain the process of determining the ideal axis of rotation for my specific case?
  9. Are there any alternative treatment options to orthognathic surgery that I should consider?
  10. What is the expected long-term outcome of the surgery in terms of my facial aesthetics and bite alignment?

Reference

Authors: Mda B, F ME, McZ D. Journal: J Stomatol Oral Maxillofac Surg. 2022 Jun;123(3):345-352. doi: 10.1016/j.jormas.2021.06.004. Epub 2021 Jul 6. PMID: 34237437