Restorative options for root filled teeth

Question 1

what is the root filled tooth at risk of

Answer 1

Question 2

what other 2 things is the root filled tooth risk of

Answer 2

Question 3

what is the risk of patient not having pulp

Answer 3

Without pulp, patients don’t know what they’re doing so much- overload, biting
How do we preserve dentin,enamel yet still achieve root canal

Question 3

what are the 4 principles of restoring root filled teeth

Answer 3

Question 4

what is restoration

Answer 4

Question 5

describe the coronal tissue assessment before RCT

Answer 5

Question 6

what other factors would you consider in coronal tissue assessment

Answer 6

Question 7

what is the ferrule effect

Answer 7

Post is going to fill the canal
Crown isn’t going to overload
Needs to be the right occlsuions
Prepare post
Instead of using tooth tissue, the crown is overlapped

Occlusal forces supported by crown are transferred around the root
Encircling of natural tooth is achieving the ferrule effect
1.5-2 mm of overlap of crown beyond that natural tooth tissue

Question 8

what is the Nayyar type core

Answer 8

Molar
Place composite in
And place large composite into coronal aspect of root canal
Crown on the top achieving ferrule
Core - enough tooth tissue to bond too

Question 9

Question 10

Why do we use posts

Answer 10

Question 11

Describe different types of post

Answer 11

Question 12

Question 13

what are the lab stages involved in cast post and core

Answer 13

Rarely done due to better alternatives

• a post is cast along with the core in the lab and this single unit is then cemented into the tooth at a further visit
• a temporary post and core is needed between appointments

Question 14

the first stage of post involves

Answer 14

Lab casts up the dental impression

Pour it , they have a model
sLab can construct a post

Question 15

what is an endo crown

Answer 15

Question 16

what is failure of restored root filled teeth

Answer 16

Drill into root canal
Angulations wrong
Rubber dam

• root fracture
• fractured post
• poor coronal seal

Question 17

1. Why are root-filled teeth structurally weaker?

Answer 17

➡️ Once the pulp is gone:

❌ No proprioception ➝ can’t sense biting forces properly
🔨 Weakened structure ➝ due to access cavity + caries
🦷 Increased fracture risk from normal chewing forces

Question 18

🔐 2. What are the main goals of restoring a root-filled tooth?

Answer 18

✅ Protect tooth structure
✅ Prevent reinfection
✅ Restore function & aesthetics
✅ Maintain periodontal health
✅ Provide a coronal seal to block bacteria
✅ Prevent over-eruption & drifting by maintaining contact points

Question 19

💫 3. What is the Ferrule Effect?

Answer 19

🦷 A 360° band of 1.5–2 mm sound tooth structure that:

Reinforces the tooth
Helps resist fracture
Distributes occlusal forces
Is vital for post/core success
📍 Think of it like a metal ring around a barrel – it holds everything together! 💍

Question 20

🔍 4. Why is a ferrule so important?

Answer 20

🛡️ Boosts fracture resistance
📉 Reduces stress on post/core
🔁 Prevents failure from torque or lateral forces
🌟 Increases longevity of restoration
✅ More important than post type!

Question 21

📏 5. What are the ideal ferrule dimensions?

Answer 21

📏 Height: 1.5–2 mm
🌍 Ideally 360° around tooth
✅ On natural dentine
🚫 Shouldn’t invade biological width

Question 22

🛠️ 6. What if there’s no ferrule available?

Answer 22

🔧 Try to create one using:

🦷 Crown lengthening
🦷 Orthodontic extrusion
❌ Extract if not restorable

Question 23

🧪 7. What are the treatment options for root-filled teeth?

Answer 23

🔹 Extract ❌
🔹 Retain and restore:

Direct restoration (composite/amalgam) 💎
Indirect restoration (onlay/crown) 👑
Post + Core when needed 🪛

Question 24

🧠 8. What assessments must be done before restoring?

Answer 24

📋 Endodontic – success of RCT, canal shape 📋 Periodontal – probing depths, mobility 📋 Coronal Tissue – height (ferrule?), thickness, cracks

Question 25

🪞 9. What aesthetic & occlusal factors should be considered?

Answer 25

🎨 Tooth colour, shape, visibility 🦷 In occlusion? 🔄 Contributes to lateral/protrusive guidance? 📌 Post-crowned canines should NOT guide – switch to group function 📌 Posterior = ICP contact only 📌 Anterior = incisal guidance shared

Question 26

🎯 10. When is a direct restoration enough?

Answer 26

✔️ Sufficient coronal tissue ✔️ Minimal wall loss ✔️ Low occlusal load 🦷 Composite or amalgam may work just fine 🔄 GP reduced to CEJ + RM-GIC over it

Question 27

🧱 11. What is a Nayyar Core?

Answer 27

A “core-within-the-canal” design 🧩: Uses coronal part of canal Composite or amalgam placed No post needed Crown sits on top to create ferrule 👑

Question 28

🪛 12. When do you need a post?

Answer 28

⚙️ If there’s insufficient coronal structure to hold the core ⚠️ Posts do NOT strengthen the tooth 😬 Over-prepping for a post may cause more harm

Question 29

📏 13. What are the ideal post dimensions?

Answer 29

🔹 Length ≥ crown height 🔹 4–5 mm of GP left apically 🔹 Diameter < 1/3 root width 🔹 Respect the canal anatomy

Question 30

🧵 15. How is a prefabricated post placed?

Answer 30

Remove GP with GG burs Shape canal with parapost drills Try-in fibre post Cement in canal Place composite core

Question 31

🧩 14. What types of posts are available?

Answer 31

✨Prefabricated (chairside): 🔸 Stainless steel 🔸 Titanium 🔸 Fibre-reinforced composite 💖 ✨Cast post and core (lab-made): Custom-fit Post & core are one unit Requires impression + lab stage 🧪

Question 32

🔧 16. How is a cast post & core placed?

Answer 32

Prepare canal Take impression using plastic post & silicone Send to lab 🧑‍🔬 Fit custom metal post & core Cement + restore with crown 👑 👉 Use temp core between visits

Question 33

🧠 17. What is an Endo Crown?

Answer 33

A monolithic crown that: Extends into pulp chamber (no separate post) No ferrule needed Ideal for molars with wide pulp chambers Still under research 🧬

Question 34

⚠️ 18. What are the common failures of restored root-filled teeth?

Answer 34

💔 Coronal leakage ➝ reinfection 💔 Root fracture 💔 Post fracture 💔 Poor angulation (rubber dam issues) 💔 No ferrule ➝ restoration fails

Question 35

👑 19. When do you use cuspal coverage (onlays/crowns)?

Answer 35

🦷 Posterior teeth: more fracture risk 🧱 If: 1 wall missing ➝ consider it 2+ walls missing ➝ must do it ✅ Class I with all thick walls = may not need 🔁 Design to conserve as much natural tooth as possible

Answer 36

1.5-2mm ring of healthy tooth tissue above margin