Dentofacial Deformities

Question 1

Causes of skeletal malocclusion

Answer 1

Trauma
pathology
congenital
developmental

Question 2

Trauma

Answer 2

condylar fracture

radiation therapy

Question 3

Pathology

Answer 3

TMJ internal derangement

Acromegaly

Question 4

Congenital

Answer 4

Cleft lip and palate
teachers collins syndrome
hemifacial microsomia

Question 5

Developmental

Answer 5

Malocclusion

Condylar hyperplasia

Question 6

3 treatments of skeletal malocclusion

Answer 6

1. growth redirection
2. orthodontic camouflage
3. orthognathic surgery

Question 7

Orthodontic camouflage

Answer 7

Accentuate dental compensations

opposite movement of pre-surg ortho

possibly less stable

perio compromise

possible esthetic compromise

Question 8

Growth redirection

Answer 8

Must have remaining growth

TMJ considerations

Limited correction possible

compliance and burnout

Question 9

orthognathic surgery

Answer 9

Combined ortho and surgery to manage a malocclusion

Question 10

advantages of orthognathic surgery

Answer 10

increased stability

decreased treatment time

improved occlusion

improved esthetics

Question 11

indications for orthognathic surgery

Answer 11

Skeletal discrepancy with masticatory difficulty

impingement on palatal tissue

speech difficulty

OSA

psychosocial problems

esthetics

Question 12

indications for orthognathic surgery

Answer 12

Skeletal discrepancy with masticatory difficulty

impingement on palatal tissue

speech difficulty

OSA

psychosocial problems

esthetics

Question 13

Phases of orthognathic surgery

Answer 13

Combined treatment plan with ortho and surgery

pre surg ortho (12-18 months)

Surgery

post-surgical ortho (6 months)

Question 14

Can all facial types have a normal occlusion?

Answer 14

True

Question 15

General facial form is defined by….

Answer 15

N’ -A’ ‘Pg’ line

Question 16

What can be used as a guide for skeletal relationships?

Answer 16

overjet

molars

Question 17

Maxillary AP hyperplasia?

Answer 17

class 2 deformity

Question 18

Mandibular AP hypoplasia?

Answer 18

Class 2 deformity

Question 19

Vertical maxillary hyperplasia?

Answer 19

Class 2 deformity

Question 20

Maxillary AP hypoplasia?

Answer 20

Class 3 deformity

Question 21

mandibular AP hyperplasia?

Answer 21

class 3 deformity

Question 22

vertical maxillary deficiency?

Answer 22

class 3 deformity

Question 23

Class 2 is more common but doesn’t require surgery as often

Answer 23

Class 3 is less common and requires surgery more often

Question 24

Model surgery?

Answer 24

Reproduce on mounted models what the surgical plan is

fabricate surgical stents

Question 25

How is the vertical position determined during surgery?

Answer 25

By the K-wire placed in nasion

Question 26

how is the AP and transverse determined during surgery?

Answer 26

By the stent

Question 27

Bilateral Sagittal split ramus osteotomy (BSSO)

Answer 27

Intraoral

potential for IAN injury

Advancement or setback

May not be stable when used for open bite(counterclockwise rotation)

Stable rigid internal fixation possible

Most frequently used mandibular procedure

Question 28

Maxillary surgical procedures

Answer 28

Anterior segmental
posterior segmental
Lefort 1
High leforte (2 and 3)

Question 29

LeForte 1 Osteotomy

Answer 29

Can move maxilla in all planes

Stable treatment of anterior open bite

allow sementalization of the maxilla

low morbidity

internal rigid fixation possible

Question 30

Obstructive Sleep apnea

Answer 30

Patients without obesity

unable to tolerate CPAP

No evidence of redundant pharyngeal soft tissue

MMA has been shown to remove need for CPAP in 100% of patients in one study

Question 31

morbidity of orthognathic surgery

Answer 31

Very limited

usually overnight hospital stay

can perform as outpatient(OMFS clinic)

sensory nerve deficit possible

Rarely need for intermaxillary fixation

incisions are intraoral

high satisfaction