Veneer Restoration Types
Feldspathic porcelain
Cast or pressed ceramic
Heat/pressure/light processed composite
Hydrofluoric acid (9%) etching for 4 minutes on internal aspect of veneer is the most important aspect for
Bonding; silanation enhances bond
Maryland bridges
Indications
Young permanent teeth, minimal restorations, short span
Temp to let ridge heal after O.S.; minimal overbite
Contraindications
Insufficient enamel on abutments
Anterior procedures
Clear occlusion
Remove fluoride rich layer
Cingulum rest positive vertical seat
Proximal wrap, 180 degrees, grooves
Posterior procedure
Single path of insertion
Proximal resistance form, parallel proximal planes
Cover as much F and L as possible, 180 degrees
Include L cusp if occlusal permits
Vital Bleaching
Tooth discolorations
intrinsic stains- congenital, systemic, metabolic, pharmacologic, traumatic or iatrogenic
erythroblastosis fetalis, porphyria, jaundice, amelogenesis imperfecta, dentinogenesis imperfecta,
tetracycline, enamel dysplasia (hypoplasia and fluorosis), amalgam pigment, trauma/pulpal injury
extrinsic- superficial enamel
pitting, plaque and calculus, metals, food stains, tobacco, orange stain, green stain
extrinsic stain can be removed with prophy cups and other cleaning devices or with disks
The chemistry of bleaching natural teeth
Unstable peroxides break down into unstable free radicals; free radicals oxidize organic pigmented
molecules which change ring structures to unsaturated chains and further to hydroxy groups; pigments
become lighter with each step of the reaction; end product of complete oxidation produces water
and carbon dioxide
The basic process almost always involves oxidation, at which time the molecules causing the discoloration
are released; consequently, the technique's success depends on the ability of the bleach to permeate
to the source of the discoloration and remain there long enough (or frequently enough) to overcome
the stain
Clinical steps to consider when treatment plan includes re-shaping the natural dentition
Photos and study models
Line drawing
Use fine diamonds (micron), carbide finishing burs and a sequential series of abrasive disks
Evaluate protrusive function.
Apply post-op 2% NaF
Modified McInnes Technique
Effective for mild to moderate fluorosis staining and superficial hypoplasia
Place McInnes solution on tooth for 5 minutes
one part diethyl ether
five parts 36% HCL acid
five parts 30% H2O2 solution
Use a fine cuttle paper disk to remove the surface layer of the enamel (approximately 15 seconds)
Repeat step #2 PRN (3-5X)
Using a cotton applicator, neutralize the teeth with a 5.25% NaOCl solution and wash with water before
rubber dam removal
Polish enamel and use fluoride (2% NaF) treatment
Acid pumice microabrasion
Indications
Superficial hypoplasia and mild to moderate fluorosis stains
Procedure
Pumice teeth and isolate with rubber dam
Use PREMA system or mix a thick paste of 18% HCl and apply to stained teeth with tongue blade
or PREMA cups mounted on gear reduction handpiece supplied with system -apply for 5 seconds
and rinse for 10 seconds
Repeat for up to 15 applications
5 applications results in an average enamel loss of 46 microns
Apply 2% NaF and remove rubber dam
Thermocatalytic technique
Effective for mild to moderate fluorosis and tetracycline-type stains
Acid etch for 5-10 seconds and rinse for 30 seconds
Bleach tooth (teeth) with 35% H2O2; place one thickness of gauze over teeth, and keep teeth wet
throughout the procedure with H2O2 by reapplying every 5 minutes
Heat can be supplied in two different ways depending on the number of teeth being bleached
position light 12 " from patient
no anesthesia- stop if patient is uncomfortable***
keep lips moist with water
flush teeth with warm water and remove rubber dam
repolish teeth and provide F treatment
Home bleaching
Fabricate nightguard (vacu-form type .020", .030", .035 optimal, .060 for bruxers)
If done, the gel will be expressed out the tray from the occlusal force
Debatable whether to include gingival coverage
Place 2-3 drops of 10% carbamide peroxide (or a hydrogen peroxide solution: carbamide peroxide solutions
containing carbopol
Have higher viscosity and are slow oxygen releasing agents-so it releases oxygen over a longer period of
time into the tray area of each tooth to be bleached
Patient wears the trays for 4-20 hours per day for 3-4 weeks
Following bleaching, you must wait 6 weeks for enamel crystal structure to remineralize for an optimal
bond to composite
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