D1 Endodontics (Exam I)

Question 1

What is Endodontics?

Answer 1

• Deals with the diagnosis and treatment of pulpal and periradicular diseases
• It is concerned with the morphology pathology and physiology of the dental pulp and periradicular tissues

Question 2

What does Endodontics Encompass?

Answer 2

1) Diagnostic phase; identify disease state and treatment plan

2) Preparatory phase; isolation with rubber dam
- Access; cleaning and shaping

3) Obturation; seal the root canal system with inert material
4) Restoration

Question 3

Basic principles of endodontics

Answer 3

• Clean , shape, & obturate the root canal system

- Need to properly restore the tooth and re-establish occlusion

Question 4

How to achieve endodontic success?

Answer 4

1) Need to have an accurate diagnosis
2) Good access
3) Thorough cleaning and shaping
4) Effective obturation
5) Quality restoration to prevent future recontamination of the sealed root canals

Question 5

Describe the Root canal anatomy

Answer 5

• The root canal system has an infinite amount of configurations to complicate its thorough cleaning
• It has branches that exit in a variety of locations,in the apex, bi or trifurcation, mid root
• These exits are where break down products exit the root canal system and elicit pathology

Question 6

What is the Purpose of endodonic preparation?

Answer 6

1) Create a properly shaped canal that is continuously tapering from access to apex.
2) Remove restrictive dentin allowing better ingress of irritants to facilitate cleaning of the canal
3) Eliminate irregularities and cul de sacs and isthmuses

Question 7

Describe the Maxillary CENTRAL incisor

Answer 7

• Only one root
• Canal is fairly round
• Canal is located usually above incisal edge
• Pulp commonly takes a distal curvature

Question 8

Describe the Maxillary LATERAL incisor

Answer 8

• Average length 22mm
• 1 canal 99.9% of the time
• Typically have distal bend at apex of root

Question 9

Describe the Maxillary CANINE

Answer 9

• Average length 26.5mm
• Sometimes longer than 31 mm
• 1 canal 99.9% of the time
• Usually longest tooth
• Very narrow in apical third
• May have pronounced curve

Question 10

Describe the Maxillary 1st premolar

Answer 10

• Average length 21.8
• 1 canal 9%
• 2 canals 85%
• 3 canals 6%
• Normally two roots and two canals
• Sometimes one root and two canals
• Roots cure mesio-distal or bucco-palatal
• Rarely, can have three roots
• May have very deep pulp chamber then split

Question 11

Maxillary 2nd premolar

Answer 11

• Average length 21mm
• 1 canal 75%
• 2 canals 24%
• 3 canals 1%
• Single root more often than the first premolar
• Usually fairly straight
• May have two canals that often merge apically

Question 12

Describe the Maxillary first molar**

Answer 12

• Average length 19.5mm
• 3 canals 6%
• ***4 canals 94%
• 1 to 3 roots
• From 2 to 4 canals
• *Most variable tooth, endodontically

Root names:
Mesio- buccal
Distal buccal
Palatal

-2nd canal mesial buccal root referred to Mesial Palatal or MB2

• Mesiobuccal root has
• Single foramen 80%
• 2 foramen 20%
• 2 canals ~90%

Question 13

Describe the Maxillary second molar

Answer 13

• AVG Length 20.0 mm
• 3 roots 60% of time
• Closely resembles 1st Molar
• Usually only 3 canals
• 4 canals can be found but are in close proximity
• 2 roots only 25% of the time
• 1 root 10% of the time

Question 14

Describe the Maxillary third molar

Answer 14

• Usually 2 or 3 canals
• Often buccal canals common orifice
• Orifices of canals are close together

Question 15

Describe the Mandibular central incisor***

Answer 15

• Average length 21.5mm
• Typically shorter than mandibular lateral incisors
• 1 canal 70%

**2 canals 30%- 40%

Question 16

Mandibular lateral incisors?

Answer 16

-Average length 22.4mm
-1 canal 57%
-2 canals 43%
-Very similar to central
-Usually longer than central incisor by approximately 2mm
Often curves distally

Question 17

Mandibular canine?

Answer 17

• 2nd longest tooth in the dentition
• May be two canals which often join apically
• Usually large canal
• May curve distally or labially

Question 18

Mandibular first premolar?

Answer 18

• Average 21.4mm
• 1 canal 73.5%
• 2 canals 26%
• 3 canals 0.5%
• Often have double canals
• 30% two roots
• Lingual canal difficult to find
• Variable morphology results in difficult RCT

Question 19

Mandibular second premolar?

Answer 19

• Average length 21.4mm
• 1 canal 85.5%
• 2 canals 14%
• 3 canals 0.5%

Question 20

Mandibular first molar?

Answer 20

• Average length 20.9mm
• 2 canal 6.5%
• 3 canals 64.5%
• 4 canals 29%
• Usually 3-4 canals 2 mesial 1 distal
• Distal canal may severely curve at apex
• Mesial canals usually curved along entire length
• Great deal of variation in morphology
• Distal canals may have common orifice
• Rarely have just 2 canals

Question 21

Mandibular second molar?

Answer 21

• Average length 20.8mm
• 3 canals 53%
• 4 canals 47%
• Number of canals can vary from 1,2,3, or 4
• May have a “C “ shape canal system
• Sometimes mesial & distal canals join @ apex

Question 22

Mandibular third molars?

Answer 22

• Rarely has 4 canals
• Often has two canals
• Shorter than other molars
• Can have very curved canals & be difficult to treat