ARTIFICIAL SALIVA

There have been numerous reports of possible allergic reactions to mercury and mercury salts and to the mercury, silver and copper in dental amalgam as well as to amalgam corrosion products Studies of the release of mercury by amalgams into distilled water, saline and artificial saliva tend to be conflicting and contradictory but, overall, the data indicate that mercury release drops with time due to film formation and is less than the acceptable daily intake for mercury in food . Further, while metallic mercury can sensitise, sensitisation of patients to mercury by dental amalgam appears to be a rare occurrence. Nevertheless, there is a growing trend to develop polymer-based posterior restorative materials in order to eliminate the use of mercury in dentistry. 

Multiphase gold or palladium-based alloys never show dissolution of Au or Pd but often exhibit progressive surface ennoblement due to selective dissolution of copper or silver from the outer 2-3 atomic layers Heat treatment often decomposes multicomponent alloys into a Pd-Cu rich compound and an Ag-rich matrix with corrosion of the latter phase in deaerated artificial saliva and S -containing media . Au-Cu-rich lamellae have similarly been observed, again with preferential attack on Ag-rich phases or matrix. These effects presumably arise from the ability of the noble alloy phases to catalyse the cathodic reduction of oxygen . 

Ishizaki, N. Corrosion Resistance of Ag-Pd Alloy System in Artificial Saliva An Electrochemical Study , Journal of the Osaka Dental University, 3, 121-133 (1969)... 

A migration test was developed to simulate human exposure patterns. 5 g of rubber material was cut into 1-2 mm stripes and then immersed in 20 ml of standard test solution of artificial saliva (4.2 g NaHC03, 0.2 g K2CO3, 0.5 g NaCl, 0.03 g NaNO, ad 1000 ml with aqua dest.j. After 24 h incubation at 40 C volatile nitrosamines were determined in an aliquot and determined after destination with a standard technique (GC-TEA-method). 

Migration of N-nitrosamines from nipples and pacifiers after incubation in a standard test with artificial saliva for 24 h at 40 C. Concentrations in ug/kg rubber product (- <1 ppb)... 

This eponymous method is widely used and as originally proposed or in modified form has served as a benchmark for other methods. In fact, it is often referred to simply as the in vitro digestibility. The first stage involves anaerobic incubation at 38°C in the dark with partially filtered rumen liquor which has been buffered with McDougall s artificial saliva solution, previously saturated with CO. ... 

In artificial saliva, release of fluoride has been shown to be reduced [234,235], a finding that may be the case for all ions released by glass-ionomer cements. There are two possible explanations for this (i) that the higher ionic strength of the external medium reduces the rate at which ions can be dissolved into it, and (ii) that the artificial saliva contained calcium ions [236], which may precipitate CaF2 on the surface, and thus impede ion transfer from that surface [237]. 

B.F. El Mallakh, N.K. Sarkar, Fluoride release from glass ionomer cements in deionized water and artificial saliva. Dent. Mater. 6 (1990) 118-122. 

B. Levallois, F. Yannick, L. Lapeyre, J.Y. Gal, In vitro fluoride from restorative materials in water versus artificial saliva medium (SAGF), Dent. Mater. 14 (1998) 441-447. 

P. Karantakis, M. Helvatjoglou-Antoniades, S. Theodoridou-Pahini, Y. Papadogiannis, Fluoride release from three glass ionomers, a compomer, and a composite resin in water, artificial saliva, and lactic acid, Oper. Dent. 25 (2000) 20-25. 

Alternatively, the amount equivalent to 30 bites or drinks may be added then in step 5, 30 ml of artificial saliva is added (assumes food is in the mouth for 30 sec and the average simulated saliva flow rate is 2 ml/min Bourne, 1982). 

More artificial saliva may need to be added to ensure that all food particles come in contact with the artificial saliva. This would be similar to an increased saliva stimulation from a... 

Adding water instead of saliva may be sufficient for foods that would not be affected by the enzymes or buffering of the artificial saliva, such as soft drinks. 

In comparison with metals, aluminium oxide releases very few ions. This is measured in several ways, one of which is by inserting the implant material in artificial saliva for 6 months. After this period the number of released metal ions is measured by means of special trace analysis techniques. 

Van Ruth, S.M., Roozen, J.P. and Cozijnsen, J.L. (1995) Changes in flavour release from rehydrated diced bell peppers (Capsicum annuum L.) by artificial saliva components in three mouth model systems. Journal of the Science of Food and Agriculture 67, 189-1 96. 

Treatment of patients with reduced salivary flow should include the following (1) drug and dosage changes by the patient s physician in consultation with the patient s dentist (2) use of artificial saliva in a spray form (3) use of mouth moisturizers and lip balms (4) use of sugarless hard candy (5) frequent sipping of water (6) use of decaffeinated products (7) use of pilocarpine (Salagen) 3-5 x daily and (8) inclusion of citrus and pineapple flavors in the diet. 

Figure 11. Images of biaxial flexural device (a) loading piston and three-ball support (b) disc specimen positioned in the flexural device and immersed in artificial saliva with heating element (c) general view of the biaxial flexural loading device [5]...

Figure 17. Biaxial flexural strength, as a function of stress rate (a) and predicted flexural strength as a function of time to fracture (b) for UST dental porcelain, with and without ion exchange, in artificial saliva at 37°C. In a),(Jjo is the scaling parameter and n is the slow crack growth, SCG, susceptibility coefficient. Inert strength was determined at 100 MPa/s in air with a drop of silicone oil on the tensile surface to inhibit the occurrence of SCG. In (b), the slope of fitted curve is related with n. Data from [63,71]...

Yoshimura HN, Pinto MM, Gonzaga CC, Cesar PF. Effects of artificial saliva storage on flexural strength and lifetime prediction of a dental porcelain. Ceramica 2009 55(334) 190-198. 

An extraoral device was used to adjust the flow rate of a 0.1-mm-thick film of artificial saliva over an agarose disk to determine the clearance half-time in the same manner as that performed intraorally (Dawes et al, 1989). Then, from the relationship between the intraoral and extraoral half-times, the salivary film velocities of the UAB and UPB sites were estimated. The half-time at UAB and UPB were evaluated by the method of study 2.1. 

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