Introduction

Question 1

What is orthodontics

Answer 1

• it is the speciality of dentistry concerned with growth and development of teeth, face and jaws
• diagnosis, prevention and correction of dental and facial irregularities

Question 2

What does an ortho assessment include?

Answer 2

A systematic evaluation of the face and skeletal bases in 3D

Question 3

What are the position of the teeth determined by

Answer 3

depend to a large extend on the size, shape and relative position of the underlying bones (maxilla and mandible) and this is genetic

Question 4

Where is the determined position of the maxilla and the mandible

Answer 4

For the maxilla - it is the basal bone, the most inner part of the maxilla just below the bone

For the mandible - it is the most inner part of the mandible between the lower lip and chin

The relationship between these 2 is what determines the skeletal relationship

Question 5

What is important when assessing these landmarks and determining the skeletal relationship

Answer 5

The orientation of the head is very important as if the head is tipped forward then hte mandibular point would be further behind the maxilla

Frankfurt plane has to be horizontal to the floor

Question 6

What is the frankfurt plane?

Answer 6

It is from the top of the ear to the orbital rim

Question 7

What should be the normal skeletal relationship

Answer 7

The mandibular base should be 2-3mm behind the maxilla in what is known as class 1

Question 8

What is a class 2 skeletal relationship

Answer 8

The maxilla is is more infront of the mandible than it should be

We would expect an overjet

Question 9

What is a class 3 skeletal relationship

Answer 9

The maxilla and mandible are almost in line

May even be infront

Would expect to see a reverse overjet

Question 10

If the mandible seems very small what would we expect this to be

Answer 10

Mandibular hypoplasia

Question 11

If the mandible is the right size but further back what is this called

Answer 11

Retrognathia

Question 12

If the mandible is larger than it should be what is it called

Answer 12

Mandibular prognathism

Question 13

What is hemimandibular hypertrophy

Answer 13

• tends to happen mainly in females - late teens/early 20s
• aetiology is not understood
• the condylar cartilage is still dividing and producing bone
• mandible and its ramus continue to grow

Question 14

What is hemifacial microsomia

Answer 14

• failure of the development of the condyle ramus and body to variable degree

Results in

• malformed ear (deafness)
• progressive facial asymmetry because as they grow older and the muscles on the normal side continue to grow the asymmetry progresses
• occlusal problems

Question 15

What is used to help diagnose skeletal problems

Answer 15

lateral cephalometry

Question 16

What are the treatment for skeletal discrepancies in growing patients

Answer 16

Growth modification techniques to promote or restrict growth of either jaw

• functional appliances
• headgear - to restrict mandibular growth
• reverse pull facemask and RME to encourage maxillary growth

Question 17

What is the treatment for skeletal discrepancies in adults who have completed growth

Answer 17

• orthognathic surgery
• single jaw or bimaxillary procedures

Question 18

What do functional appliances do

Answer 18

• they modify jaw growth
• often two seperate appliances called a twin block and they are worn 24h a day

Question 19

What is the most common orthognathic surgery

Answer 19

bilateral sagittal split osteoctomy

a type of jaw surgery in which the lower jaw (mandible) is split bilaterally (moved forward or backward) to straighten it to a more balanced and functional position

Question 20

What is Le Fort I Osteotomy

Answer 20

type of orthognathic surgery

the teeth are chopped off the jaw and moved and they are secured by pins and screws in a predetermined position

Question 21

Who makes up the orthognathic team

Answer 21

• orthodontist
• maxillofacial surgeon
• clinical psychologist
• maxillofacial technician
• speech therapist
• GDP

Question 22

What are the different types of clefts

Answer 22

• cleft lip
• cleft palate
• cleft lip and palate (uni or bilateral)

Question 23

Who is the team for cleft lip and palate

Answer 23

• orthodontist
• cleft surgeon
• ENT
• speech therapy
• maxfax surgeon
• plastic surgeon
• dental practitioner

Question 24

What are issues those with cleft lip & palate endure

Answer 24

• issues with deafness
• lots of patients have class 3 and defecit of bone in the region where the canine would come through so they often need an alveolar bone graft from their hip to allow the canine to come through

Question 25

What can go wrong in the growth and development of teeth?

Answer 25

* increased overjet * deep overbite * anterior cross bite * posterior cross bite * retained decidious teeth * early loss of decidious teeth * ectopic teeth * impacted first molars * crowding * spacing * trauma * habits * anterior open bite * lateral open bite * ankylosis of decidious teeth * cysts * diastema * supernumaries * dental asymmetries * others

Question 26

What is the arrow pointing to?

Answer 26

A submerging decidious molar The tooth developed and at some point the tooth became ankylosed and everything else grew aroud it

Question 27

What are the arrows pointing to?

Answer 27

* tuberculate supernumeracies * they are in the way and need to be taken out in hope the centrals will come in

Question 28

What are occlusal and dental anomalies

Answer 28

* crowding * spacing * increased overjet * reversed overjet * anterior open bite * deep bite * hypodontia * supernumeries * anterior cross bites * posterior cross bites * ectopic teeth * delayed dental development * other anomalies e.g fusion of conical supernumeracy

Question 29

What is hypodontia?

Answer 29

* fewer than normal number of teeth

Question 30

What is supernumeraries?

Answer 30

In addition to normal number of teeth

Question 31

When assessing the teeth face and jaws what do we look at in order to reach our orthodontic diagnosis?

Answer 31

* facial anomalies, asymmetries * skeletal relationship (how the jaws relate to each other) * skeletal relationship (how the jaws relate the skull base) * teeth in each arch separetly * occlusion (how they bite together)

Question 32

What special tests are useful for orthodontic diagnosis?

Answer 32

* study models * radiographs (OPG & lateral cephalogram) * photographs * sensibility testing * CBCT

Question 33

What are the aims of orthodontic treatment?

Answer 33

* stable * functional * aesthetic occlusion * prior to restorative work

Question 34

What are the types of appliances?

Answer 34

* removables * functionals * fixed Others: * aligners, invisalign * headgear, reverse pull HG * temporary anchorage devices

Question 35

What are removable appliances for?

Answer 35

* tip teeth * open bites * maintain space

Question 36

What are fixed appliances for?

Answer 36

* true 3D control of tooth position

Question 37

What are the benefits of orthodontic treatment?

Answer 37

* improve function (e.g anterior cross bite or open bite can make it difficult to incise food) * improve appaerance (aesthetics) * improve dental health (make teeth easeir to clean) * reduce risk of trauma (those with overjet at increased risk) * to faciliate other dental treatments (rearrange spaces in hyopdontia cases prior to bridges or implants)

Question 38

What are the risks of orthodontic treatment

Answer 38

3 main risks * decalcification (poor brushing) * relapse (lack of retainers) * root resorption (1 in 500) Others * pain, discomfort * soft tissue trauma * failure to complete tx * loss of tooth vitality * inhale or swallow small components * candidal infections