Fundamentals of Operative Dentistry Balwant Rai, Jasdeep Kaur
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Cement and Tooth Colored Materials1

 
Table 1.1A   Comparison of tooth colored materials
Compressive strength PSI
Tensile strength PSI
Flercre strength PSI
Modulus of elasticity
Setting shrink (V)
Hardness knoop
Water sorption
Solubility % in
Enamel
40-56000
2.3
300
Dentin
36-50000
7500
12 millions
65
Silicate
24000-31000
700
3.1 millions
0.25
65
0
1.4-2
ASPA
23100-28000
650
1.9 millions
0.2
60
0.01
0.4
Unfilled resin
10-11000
4000
260000
7
16
7
0.1
Filled resin
8000
1500
1
100000
5
80
5
0.7
Corporate resin
Ist-generation
7000
10000
0.5
30-100
1.5
0.3
6400
14000
45000
90000
16000
IInd-25000
Hybrid-55000
Table 1.1B   Comparison of tooth colored materials
Color stability
Biologic form
Silicate
None of these materials enamel are as color as tooth with age
1. Microleakage and disintegrated increase
2. Original acidity of cement which remain high upto one week
Unfilled and filled resins
–do–
1. High coefficient of thermal expansion
2. Exothermic heat of polymerization
3. Enamel etching acid accidentally applied on dentin.
Composite resin
–do–
1. Surface roughness allowing plaque accumulation especially around gingival margins
2. Leakage
3. The exothermic heat of polymerization
PSPA
–do–
1. Surface roughness that lead to plaque accumulation
2. Acidity of the original lingual and non-set matrix
2
Table 1.1C   Comparison of tooth colored materials
Silicate cements
Zinc phosphate
Zinc oxide-Eugenol
Glass ionomer
Calcium hydroxide
Zinc polycarboxylate
Composition
Powder - alumina, silica, cryolite, sodium fluoride, calcium phosphate, calcium fluoride
Powder - zinc oxide, magnesium oxide, silica and otder oxide
Powder - zinc oxide, zinc stearate, white rosin, zinc acetate and magnesium oxide
Powder - alumina, silica calcium fluoride, aluminium fluoride, aluminium phosphate sodium fluoride etc.
Base paste - calcium sulphate, glycol salicate titanium doxide and calcium tungstate
Powder - zinc oxide, oxides of bismuth and aluminium, magnesium oxide and stannous oxide
Liquid - phosphoric acid, aluminum phosphate or magnesium phosphate and water
Liquid - phosphoric acid, aluminum phosphate, aluminium zinc and water
Liquid - eugenol and olive oil
Liquid - polyacrylic acid and copolymer with iticonic acid, malic acid, tartaric acid, and water 4-7 minutes
4-7 minutes
calcium hydroxide, zinc stearate, zinc oxide ethylene tolaesic and sulfonamide
Liquid - polyacylic acid and copolymer of acrylic acid with other unsaturated carboxylic acid
Setting time
3-5 minutes
5-9 minutes
4-10 minutes
45 seconds
2.5-5.5 minutes
Mixing time
45 seconds-
1-1.15 minutes
7-9 minutes
1 minute
150
30-40 seconds
Compressive strength (MPa)
180
103.5
3-55
6.6
10-27
55
Tensile strength (MPa)
3.5
5.5
0.32-5.3
49
1.0
6.2
Hardness (KHN)
70
Thermal properties
Lower than other restorative material
Good thermal insulators
Excellent insulating properties
Sufficiently thick layer provide thermal insulation
Good thermal properties
– severe irritant
After 3 minutes mireing pH - 3.5
PH-6.6 to 8.0 least irritating
Mild pulpal response
pH - 9.2-11.7
Initial - acidic
Biological properties
– initial pH - 2.0
it will be below 7 even after one month
Neutral after 24 to 48 hours
Bacteriostatic Obtundant
freshly mired
cement - 3.0-4.0
After 24 hours - pH - 5.0-6.0
3
Silicate cements
Zinc phosphate
Zinc oxide-Eugenol
Glass ionomer
Calcium hydroxide
Zinc polycarboxylate
Film thickness
Type-I - not more than 25 mm type-II - not more than 40 mm
Greater than 25 mm
Solubility and disintegration
It dissolves and disintegrates in oral cavity
Low solubility 0.06%wt
0.4%wt
Initial solubility high (0.4%)
0.4 to 7.8%
0.6wt
Powder/liquid portion
1.4 gm/4 ml
1.4 gm/0.5 ml
4/1 to 6/1 by wt
3/1 by wt
1.5/1 by wt
Manipulation
Liquid is dispensed just prior to miring
Stainless steel spatula is used in small margin cements brisk circulator motion
Circular motion on cool glass slab
Agateor plastic spatula used Finishing by folding method
Equal length of two pastes pricing on paste
Miring on a cooled glass slab
Clinical application
Intermediate restoration in caries active months. Esthetic restoration of anterior teeth
Temporary restoration. Cutting of restorations. Cutting of orthodontic bands and brackets High strength bases
Permanent cementation. Temporary cementation. Cavity liners. Temporary filling and thermal insulation
Liners and bases. For cutting. For restorations (anterior teeth in cervical area)
For direct and indirect pulp capping. Purification in young permanent teeth where root for motion in complete for direct and indirect pulp capping
Luting permanent restorations As bases and liners Used in orthodontics for cementation of bands