1resin bonded bridge Flashcards
rbb
resin bonded bridge
fixed prosthesis replace a missign tooth in a smmal edentulous area .its mainly invasive to tooth structure adn uses composite resin cement for retention
invasive:مجتاحه
waht does the rbb reproduce?
1 morphology of the portions prepared tooth
2 maintain its functon
3prevent future damageof remains tooth
what is the main advatage of rbb?
minimal tooth preperation
what are the types of rbb?
1 rochette
2 maryland
3 cast mesh FPD
4 virginia bridge
virgina bridge disadvantages like rochette + salt crystals
what is the first type of RBB ?
rochette bridge
what is the bonding way in 1rochette bridge?
1 perforatons in the abutment wings metal retainers create macro-mechanical retention
2 used compisite cement along side with 3 saline coping agent
what is that create adhesion in the 1rochette bridge?
saline couping agent
the failures in 1rochette bridge :
1due to no preperations- bulky lingualcompisite tends to wear
2abutment wing perforated causes weakness
3 exposure to wearof resin at the perforated
4 lach of adhesion lead to de-bonding
what comes to solve the rochette brideg failure ?
Maryland Bridge
-using micromechanical retention
- alter the surface of metal retainers and abutment preparation
whats new in the 2maryland bridge?
1 proximal and lingual and occlusal rest
2 ceramics pontic
3 sandblasted metal wing
4 more bontic higher debonding
5 should be done on none mobile abutment teeth
6 proven success rate 80% at 15 years
7 no perforations
metal parts are chemicalley etched
with what is sandblasted metal
alumina oxide particles 250mm al2o3
3 cast mesh rbb
1 non etched after casting
2 mesh like lingusle surface with macro-mechanical retention
ADVantages of RBB
1 minimal prep
2 high strength alloy
3 simple pontic and two wing
4easy to recement whe debonding
5 cheaper than implant and 3unit bridge
*its can be cleaned out and rebonded
DISadvantages of RBB
1 sensitive preperaton
2 sensitive cementaton technique
3 no occluson forc should be present
4 discoloration of abutment teeth
=anterion tooth preperation of RBB
1 lingual proximal axial into facial surface to provide faciolingual lock
3 proximal and cingulum groove
*4 keep .5 mm occlusal reduction to prevent exposure of tooth pulp
=posterior tooth preperation of RBB
1occlusal rest
2 retintive surface with enough occlusal reduction
3 proximal wrap and slots to resist lateral forces
4 generally in molars and pre covers a lingual cusp
why using th eocclusal rest?
1 resist gingival displacement
2 biting forces distribution
3place in proximal marginal areas to the edentulous space placed in oppisate side
what s the case in the premolars and molars?
1occlusial rest with exceptions in the maxillary
2 molars and premolars have lingual cusp coverage
3 mandibular full covarge cusp
2 light chamfer finish line
1mm supragingivally
RBB VS conventional bridge work
RBB higher failure rates but convetional involves bacterial penetraton through margins this lead to rct or loose of the tooth
penetraton اختراق
intraoral placement of RBB
1 cleanedabutment tooth
2 isolated area nad abutment is air DRIED
3acid tched enamel phosphoric acid
4 acid etched are rensed thoroughly
5resin is applied followed by composite resin
what we use in direct intraoral RBB?
selfcuring acrylic of composite material
with what we altered the surface of the metal rochette bridge in the maryland?
by sandblasting with aluminum oxide particles 250mm al2o3
why RBB is less tragic than conventional bridges despite the fact that failure rates of RBB is higher?
because conventional bridges failure involves bacterial penetration through margins
with what we acid etched the enamel in RBB?
phosphoric acid 30-50%
