Exodontia (2)

Question 1

Describe the anatomy of the teeth with regards to exodontia

Answer 1

Very robust and designed to withstand masticatory forces

Question 2

Describe the anatomy of the alveolar bone with regards to exodontia

Answer 2

Thin, elastic and can be deformed, but very variable depending on patient

Question 3

Describe the anatomy of the PDL with regards to exodontia

Answer 3

• Extremely strong

- Composed of collagen which has high tensile strength but is very inelastic

Question 4

Describe the anatomy of the adjacent structures with regards to exodontia

Answer 4

Inferior alveolar nerve or maxillary sinus may complicate the procedure

Question 5

Why are robust teeth relevant to exodontia?

Answer 5

Significant forces can be transmitted through it to the underlying bone and PDL

Question 6

Why is thin and elastic bone relevant to exodontia?

Answer 6

It will deform when forces are applied through teeth

Question 7

Why is an inelastic PDL relevant to exodontia?

Answer 7

It will fracture which will allow the tooth to be extracted

Question 8

Describe the root morphology of the upper arch

Answer 8

Incisors - 1 root
Canines - 1 root
Premolars - 2 roots (buccal and palatal)
Molars - 3 roots (mesiobuccal, distobuccal and palatal)

Question 9

Describe the root morphology of the lower arch

Answer 9

Incisors - 1 root
Canines - 1 root
Premolars - 1 root
Molars - 2 roots (mesial and distal)

Question 10

What is important to note about the roots of lower molars?

Answer 10

Lower 6s show high tendency to have 3 roots - Mesiobuccal, mesiopalatal and distal

Question 11

Describe Coupland’s elevator

Answer 11

• Come in 3 sizes (1 smallest, 3 largest)

- Held in hand with index finger on shaft to provide control

Question 12

Name 3 functions of Coupland’s elevator

Answer 12

1. Assess anaesthesia
2. Separate gingival cuff and prevent tearing of mucosa
3. Elevate teeth

Question 13

Describe the basic shape of upper and lower forceps

Answer 13

Upper - Straight to anterior teeth but curve slightly for posterior
Lower - Blade set at 90 degrees to handles

Question 14

Describe the patient positioning during the extraction

Answer 14

• Allows good vision, access and allow forces to be delivered down long axis of tooth
• Dentist and patient should be comfortable
• Cervical spine must be supported
• Dentists stands to ensure maximum stability and support

Question 15

Describe the positioning of the dentist and patient during maxillary teeth extraction

Answer 15

• Chair should be tipped back so maxillary plane at 60 degrees to floor
• Chair height should be patient’s mouth is at elbow house
• Patient’s head should be turned towards the dentist
• Forefinger and thumb support tooth to be extracted

Question 16

Describe the position of the patient and dentist for extraction of mandibular teeth

Answer 16

• Chair position should be such that tooth is below level of operators elbow
• Chair positioned so mandibular occlusal plane is parallel to floor
• Chair position for removal need to be reclined further back in mouth
• Stand behind when removing tooth corresponding to hand you are using and in front when the opposite (ie LL using left hand stand behind)

Question 17

Name 3 functions of the supporting hand during extractions

Answer 17

1. Counters force applied through the forceps
2. Feed-back through supporting hand to detect deformation of alveolar bone and movement of the tooth
3. Support offered by fingers protects tissue against damage if forceps incorrectly applied

Question 18

Describe the positioning of the forceps on the tooth

Answer 18

• Beaks should engage roots of the tooth
• Positioned as apically as possible
• Place beak with most limited vision first

Question 19

Name 3 forces used during exodontia

Answer 19

1. Gripping
2. Apical drive
3. Dilation of Socket

Question 20

Describe the “Gripping Force”

Answer 20

• Once beaks are in position should be gripped tightly as possible
• Prevents slipping
• If beaks move tooth is more likely to fracture during extraction

Question 21

Name 3 functions of apical pressure

Answer 21

1. Retract the gingival soft tissues
2. Place the PDL fibres under pressure and dilate PDL space
3. Help prevent the forceps beaks slipping once other forces are applied

Question 22

Describe the root and dilatation movement of maxillary central incisor

Answer 22

Root - Single, straight with circular cross section

Movements - Rotation and labial expansion

Question 23

Describe the root and dilatation movement of maxillary lateral incisor

Answer 23

Root - Oval cross section and may have distal curve at apex

Movements - Minimal rotation and labial expansion

Question 24

Describe the root and dilatation movement of maxillary canine

Answer 24

Root - Long, robust root with triangular cross section

Movements - Rotation first then labial expansion if required

Question 25

Describe the root and dilatation movement of maxillary premolars

Answer 25

Root - Possible fine twin apices | Movements - Bucco-palatal movements only

Question 26

Describe the root and dilatation movement of maxillary molars

Answer 26

Roots - 2 buccal and 1 palatal | Movements - Buccal and palatal only

Question 27

Describe the root and dilatation movement of mandibular incisors

Answer 27

Root - Single, fine, flattened and ovoid | Movement - Labio-lingual movement with emphasis on labial

Question 28

Describe the root and dilatation movement of mandibular canine

Answer 28

Root - Single robust root with ovoid or triangular cross section Movement - Rotation with occasional need for labio-lingual movement

Question 29

Describe the root and dilatation movement of mandibular premolar

Answer 29

Root - Single with circular cross section | Movements - Rotation only usually needed but bucco-lingual may be used

Question 30

Describe the root and dilatation movement of mandibular molars

Answer 30

Root - 2 roots, one mesial and one distal | Movement - Bucco-lingual movement but may be figure of eight

Question 31

Describe the delivery of teeth

Answer 31

- Once tooth has loosened it should be removed along the least line of resistance - Compress socket with fingers - Achieve haemostasis (biting on gauze)

Question 32

Describe 3 post-op instructions to give the patient on the day of extraction

Answer 32

1. Do not rinse mouth for 12 hours 2. Do not take alcohol, very hot foot or drink and avoid smoking for 7 days 3. Keep fingers and tongue away from woudn

Question 33

Describe post-op instructions for the following day

Answer 33

- Rinse gently after each meal using half teaspoon of table salt in glass of warm water - Salt water mouth rinses continue 4 days until wound is healed

Question 34

Describe post-op instructions if bleeding occurs

Answer 34

- Place damp pad of clean linen or handkerchief over wound area and bite firmly for 20 minutes - Replace if necessary with clean pad and repeat for another 20 minutes - Remain quiet, lying down with head elevated - If bleeding continues, contact the dentist / oral surgeon

Question 35

Describe post-op instructions for pain and swelling following extractions

Answer 35

1. Take pain medication as prescribed or what patient normally does for pain 2. Swelling is normal and takes 2 days to reach peak (most swollen for 5-7 days), anything above this, contact GDP / oral surgeon