CLASS V steps (summarized)
Access → 330 FG
Peripheral cavity removal w/ round #2
Round #6 or spoon excavator used for pulpal/axial walls
*** using a larger bur  = removes less tissue 
Outline form → 330 
Caries removal is first done @ periphery and along DEJ 

do until we see clean DEJ! 

Explorer used for → assessment of surface texture only 

be careful in deeper areas to not damage pulp 
do not use in axial area

When material has set, excess is shaved away w/ → No. 12 surgical blade 

Contoruing/finishing = use hand instruments as much as possible while preserving smooth surface 
If you use rotary instruments = DO NOT DEHYRDRATE SURFACE OF RESTO 


Goals of Caries Removal in the Prep:

Axial wall → selective removal to FIRM DENTIN
Periphery walls (O,M,G,D) → Hard dentin DEJ 
Occlusal and Gingival walls → parallel to slightly divergent 
M and D walls → divergent 
Margin (Butt joint margin) → NO bevels. Smooth margins and walls. 




Sandwich Tech Lecture

Full thickness bevel → all the way to DEJ 
Partial thickness = not entire enamel


GI or RMGI

Dentin replacement = GIs similar thermal conductivity and coefficient of thermal expansion
Fl release= takes place at setting rxn, the initial release is high and decreases with time
Chemical bonding to dentin 


Why RMGI?

Superior mechanical properties than GI
Can be contoured and polished v similar to RBC 
Stronger in acidic environment = don’t want it to erode easily 
Conventional GI = poor maintenance of anatomical form 
Conventional GI suffers rapid surface degradation 
Conventional GI doesn’t present optimal esthetics = not easy to polish 


Sandwich technique = layers of GI (conventional or RM) between dentin and perm restorative material (resin composite or amalgam) 

Overall Indications of Close Sammy Technique

Pulp protection

selective Caries removal
preparation extends very close to pulp
Fl-release promotes affected dentin remin

Remaining enamel at the gingival margin

better bonding with composite than GI (GI on composite will decrease mech. Properties of resto) 
GI best at bonding with dentin



Anterior Resto indications for CLOSE SAMMY

veneered w/ composite to: 


Enhance esthetics 
enhance polishability 
increase abrasion resistance 


Posterior Restos for CLOSE SAMMY

veneered w/ composite or Amalgam for increased fracture and wear resistance 


Open Sammy Technique

layering of two directly placed materials where both exposed to saliva 
AKA: Bonded-base technique (summit) 
helps w/ fl- release to oral environment 


Open Sammy indications:

Restoration of deep cervical lesions w/ dentin or cementum margins (severely damaged teeth w/ no enamel on the margins)
Need material that contains Fl to reduce potential recurrent Caries ( = high risk pts)
The selective material for open sandwich technique is RMGI


Closed Sammy Technique 

layering of two directly placed materials, one covering the other
Dentin is covered by RMGI/GI 
GI/RMGI = completely covered by the overlaying Resto (RC or amalgam)
Liner/base = GI is placed internally (on dentin) and completely surrounded with a second material (Amalgam or RBC)
NO GI is exposed to saliva 




Closed Sandwich Technique Steps 

Prep → NO BEVEL. Butt joint only 
Rinse and dry → DON’T DESICATE, leave dentin moist (GIC needs water for Rxn) 
Apply GI/RMGI → place GI over pulpal and/or axial wall 
Check margins → do not place GI over any margins/on enamel 
Etch and rinse
Prime → Prime remaining exposed dentin- no primer on GI 
Final Resto 



Open Sandwich Steps

Prep → NO BEVEL on cementum. Butt joint only. 
Rinse and dry
Apply RMGI → place RMGI over PULPAL/AXIAL walls 
Light Cure
Etch and rinse 
Prime
Final Resto 




Technique
Indication
Contact w/ saliva?
Surfaces
Material
Closed sammy
Pulp protection (enamel on margins) 
No
Axial and pulpal walls
GI or RMGI
Open sammy
Deep cervical lesions w/ dentin or cementum margins 
Yes = Fl- release to oral einvronemnt 
ANY (except surfaces under occlusal forces) 
RMGI

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