Bsso

Question 1

What is BSSO and who is credited with improving it?

Answer 1

BSSO is the predominant orthognathic procedure for mandibular deformities.

Obwegeser improved the technique and became its strongest advocate.

Question 2

What are the two main mandibular deformities treated with BSSO?

Answer 2

1. Class III deformities (prognathism) - mandibular setback
2. Class II deformities (retrognathia) - mandibular advancement

Question 3

How does relapse differ between mandibular advancements and setbacks?

Answer 3

Relapse patterns differ between advancements and setbacks.

Prevention principles may be similar for both.

Question 4

What nerve is at risk during BSSO?

Answer 4

The inferior alveolar nerve (IAN) can be damaged during SSO.

This risk was minimized early on but is now well-recognized.

Question 5

How is TMJ dysfunction evaluated post-BSSO?

Answer 5

1. Compare post-op TMJ symptoms to pre-op findings
2. Assess changes in mandibular range of motion

Question 6

What is the primary use of genioplasty?

Answer 6

To improve skeletal abnormalities of the chin.

Primarily used for aesthetic reasons based on patient concerns.

Question 7

How is the maxilla exposed for LeFort I osteotomy?

Answer 7

Via a circumvestibular incision through mucoperiosteum.

Made horizontally above attached gingiva at level of maxillary teeth apices.

Question 8

What deformities can LeFort I correct?

Answer 8

1. Class II deformities - set back
2. Class III deformities - advancement
3. Gummy smile - shortening of maxillary height

Question 9

What does the surgical diagram show? (Page 6)

Answer 9

A: Incision
B/C: Medial exposure and osteotomy
D: Nerve location
E/F: Bone removal for adjustments

Question 10

What determines LeFort I osteotomy design?

Answer 10

The specific maxillary movement desired (advancement, setback, or shortening).