MAJOR CONNECTORS Flashcards
MAJOR CONNECTORS is
Connect parts of RPD in one side of the arch to parts in the other side.
MAJOR CONNECTORS requirement
1-must be rigid: So
A- wide distribution of stresses to all components of RPD that transferred to abutment and ridge
B- increase effectiveness of other components ‘‘rests, clasps, saddle ‘’
2- not impingement on free gingival margin to avoid laceration
3- provide means of indirect retainer
4- should be comfortable to patient
5- margins/borders not cross bony prominence
Differences among bar, plate, strap???
*Bar → width is 5mm, cross section is half pear or half round or half oval *Plate → width more than 5mm reach 8mm, cover teeth and tissue
*strap → width more than 8mm, not cover teeth only cover tissue
beading is …. And its purpose is …
beading → done in master cast modification by V-shaped depression ‘’ along borders of major connectors ‘’ 0.5; 1mm in depth and width
Function a-avoid food entrapment
b-increase physical retention
Types of maxillary major connectors
1- anterior palatal bar
2- posterior palatal bar
3- middle palatal bar
4-ring design (anteroposterior palatal bar)
5 -palatal strap
6- complete palatal coverage
anterior palatal bar indication, disadvantages
Disadvantage: 1- interfere with phonetics 2- poor tongue tolerance
Indication: 1- short span edentulous area located in anterior area
2- can be used with ring design to act as indirect retainer in distal extension (class I, II)
posterior palatal bar indications
Indications:
1- short span edentulous area located in posterior area
2- can be used with ring design to act as indirect retainer in mesial extension (class IV)
middle palatal bar advantage and disadvantage , indications
Advantages: 1-support as rest on hard palate
2-bracing as it contact slope of hard palate 3-good tongue tolerance
Disadvantage: not act as indirect retainer
Indication: short span edentulous area located at middle of arch
ring design (anteroposterior palatal bar) indications and contraindications
dications: 1-wide distributed teeth, increase in number
2-prominent torus palatinus Contraindication: high narrow palatal vault (V-shaped)
palatal strap description, advantages, disadvantages , indications
Description: Strap >8mm in width
Advantages: 1-support as increase area of coverage 2-retention by physical retention
Disadvantages: 1-poor tongue tolerance 2-may increase pressure cause papillary hyperplasia.
Indications:
1-middle palatal strap → in class III modification 1
2-anterior palatal strap → in class IV
3-anteroposterior palatal strap ( horse shoe) → in free end saddle
complete palatal coverage description, advantages,
Anterior border → 6mm away from free gingival margin
May be: 1-combined (metal and acrylic) → anterior part is metallic and posterior is acrylic to decrease its weight 2- Metal → use thin metal
Advantages:
1-support → cover large area of palate (maximum support)
2-bracing → cover lateral slopes of palate
3-retention → by physical retention
4-can act as indirect retainer
Types of Mandibular major connector
1- lingual bar
2- lingual plate
3- double lingual bar (Kennedy bar )
4- labial bar
lingual bar , advantages, indications, contraindications
Advantages: 1-simplicity of design ‘‘not complicated’’ 2-not annoy tongue
3-more hygienic and less caries
Indications: Used in all tooth supported (class III, short span class IV) and free end saddle (class I, II, long span class IV)
Contraindications: 1-insufficient vestibular depth less than 8mm
2-presence of torus mandibularis 3-lingual tipping of teeth
lingual plate disadvantage, indications
Disadvantages:
1-decalcification of teeth as decrease remineralization of teeth by saliva
2-increase risk of soft tissue inflammation especially with poor oral hygiene Indications:
1-insufficient vestibular depth ‘‘less than 8mm’’ 2-weak teeth need splint by usage of multiple rests 3-class I, II so act as indirect retainer
double lingual bar (Kennedy bar )
Advantages
Advantages:
1-support 2- bracing 3-act as indirect retainer
