Denture Design NEW

Question 1

types of saddles and kennedy classifications in denture design

Answer 1

types

 - open = saliva passes through and less irritation
 - closed = more retention as more contact 

kennedy classes

 i. bilateral free ended saddles 
 ii. unilateral free ended saddles 
 iii. posterior bounded saddle
 vi. anterior bounded saddle (crossing midline)   - use lowest class and add modification number if multiple saddles

Question 2

definition of support in denture design and craddock classifications

Answer 2

• resistance to occlusally directed load
• craddock classification
  1. tooth born
  2. mucosa born
  3. both

Question 3

retention in denture design

Answer 3

definition = resist vertical displacement

types:

 1. muscular forces 
       - saliva suction - shape of denture 
 2. physical forces
        - soft tissue undercuts, mucosa coverage  3. types of mechanical retention 
 i. Ibar clasp (gingivally approaching)
 ii. occlusally approaching self reciprocating 
 iii. "       " single arm clasp with separate reciprocating arm

Question 4

what is an RPI system in denture design

Answer 4

• reciprocation, proximal plate and I bar clasp
• rest on mesial to prevent distal axial torpur of abutment tooth
• for free ended saddle to prevent rocking

Question 5

indirect retention in denture design

Answer 5

definition - to resist rotational displacement

• find pivoting point of denture (when narrow triangle of retention) and place support to prevent rocking

types of support

• major and minor connector
• rests
• saddle
• denture base

Question 6

what is bracing and reciprocation in denture design

Answer 6

reciprocation definition = preventing mesial displacement of abutment teeth from retentative features of denture

bracing definition = prevents lateral movement of denture by i.e. bracing both sides of the hard pallet with the major connector

methods:

• reciprocal arm
• connector brought up onto teeth

Question 7

what is the role of the minor connectors in a denture design

Answer 7

connects rests, clasps and bracing arms to major connector

Question 8

types of major connector for an maxilliary denture

Answer 8

1. plate (plate/strap)
   
   • for PMMA (acrylic) or CoCr
   • thin
   • ONLY type for PMMA
   • generally for craddock class 2
2. bar (strap/ring/bar)
   
   • thicker
   • most common choice****
   • CoCr
   • less mucosa coverage
   • generally for craddock class 1
3. horseshoe
   
   • CoCr
   • ‘n’ shape design

Question 9

types of major connectors in mandibular denture design

Answer 9

1. CoCr Bars
   
   • only CoCr
   i. lingual bar
   - most common
   - use when 8-9 mm, 3mm bellow gingival margin, 4mm for bar and 1mm above floor of mouth but can be up to preference of patientii. sublingual bar
   - at the floor of the mouth
   - not used as too uncomfortableiii. dental bar
   - over teeth (doesnt touch gingiva)
   - too uncomfortable so rarely used
2. Plates (CoCr/PMMA)
   
   • ‘n’ shape design, up onto teeth and down toward floor of mouth