Flashcards in 5 - Prosthetic Tooth Materials & Linings Deck (19):
based on which material?
how does it develop resistance to crazing?
how is it connected to denture base resin?
- highly cross linked
- by a chemical bond
acrylic based artificial teeth: name one advantage and disadvantage?
- easy to modify
- susceptible to wear
materials for artificial teeth - porcelain based:
- how common?
- how is it attached to denture base resin?
- susceptible to?
- how easy to adjust?
- rarely used
- mechanically attached
- cracks around area of attachment
- difficult to adjust
other materials used for artificial teeth?
examples where it is used?
- composite resin based
- combination of materials
- used in dental implants
- less susceptible to wear
permanent soft lining materials: clinical uses?
- atrophic ridge and mucosa (soft lining gives cushioning as ridge takes more force)
- undercut ridges (flexible flange)
- obturators (flexible bung)
acrylic soft linings: 2 types?
heat cured acrylic soft lining: components?
- polyethylmethacrylate (polyme)
- butyl methacrylate
- butyl-phthalybutyl glycolate (plasticiser)
advantages of acrylic soft lining materials?
- good bonding between denture base and lining material
- material hardens over time because plasticiser leaches out
silicone soft lining materials: 2 types?
silicone soft lining materials
- polydimethysiloxane (vinyl end groups)
- bonding agent required
advantages of silicone based materials?
- maintains softness
- failure of acrylic/silicone bond
- rough surface, difficult to modify
- lining material takes up stain
- susceptible to candida colonisation
- risk of denture fracture
lab technique for acrylic/soft lining denture - how many stages?
two stage technique; acrylic curing first
lab technique for acrylic/soft lining denture - spacer constructed for?
to prevent acrylic reaching area where soft lining will be placed
lab technique for acrylic/soft lining denture: steps?
1. acrylic packed, flask closed, allowed to partially cure
2. spacer removed from model
3. adhesive applied to acrylic, molloplast packed
permanent soft lining materials & cleaning dentures
- aggressive brushing will cause?
- if cleansers is used too hot what will happen?
- will cause disturbance in bond between acrylic and lining
- changes in surface roughness and colour
temporary soft lining materials: components and its constituents?
what happens during setting? what properties does it have?
- powder: polyethyl methacrylate
- liquid: ethanol, plasticiser (flexibility)
- setting is formation of a gel, which has viscoelastic properties
clinical uses of temporary soft lining materials?
- temporary relines (for dentures undergoing modification, transition phase after implant placement)
- tissue conditioner (used in ill fitting dentures to allow recovery of inflamed tissues in denture bearing area)
- functional impressions (rebasing denture, modify fitting surface of obturator, recording neutral zone)
functional impression for rebasing: steps?
- use coe-comfort in denture base
- pt wears denture for few fats
- records impression of tissues during function
- used for rebase impression