J Adv Prosthodont.  2014 Apr;6(2):115-120. 10.4047/jap.2014.6.2.115.

Effect of aging on tear strength and cytotoxicity of soft denture lining materials; in vitro

• Landayan J
• Manaloto A
• Lee JY
• Shin SW

• KMID: 2233339
• DOI: http://doi.org/10.4047/jap.2014.6.2.115

Abstract

PURPOSE
The aim of this in vitro study was to evaluate the effect of aging on the tear strength and cytotoxicity of four soft denture lining materials.
MATERIALS AND METHODS
Four commonly used soft denture lining materials, (Coe-Comfort(TM) GC America Inc., Alsip, IL, USA; Coe-Soft(TM) GC America Inc., Alsip, IL, USA; Visco-gel Dentsply Caulk Milford, DE, USA; and Sofreliner Tough M Tokuyama Dental Corporation Tokyo, Japan) were selected. Sixty trouser-leg designed specimens per lining material were fabricated using a stainless steel mold for tear strength testing. The specimens were divided into non-thermocycling and 1000-, and 3000- thermocycling groups. For the cytotoxicity test, twenty-four disk shaped specimens per material were fabricated using a stainless steel mold. The specimens were soaked in normal saline solution for 24 h, 48 h and 72 h. Cytotoxicity was measured by XTT assay in L929 mouse fibroblasts. Data were analyzed by two way analysis of variance and Dunnett's test (P<.05).
RESULTS
Before thermocycling, Sofreliner Tough M (10.36 +/- 1.00 N) had the highest tear strength value while Coe-Comfort(TM) (0.46 +/- 0.10 N) had the lowest. After 3000 cycles, Sofreliner Tough M (9.65 +/- 1.66 N) presented the highest value and Coe-Comfort(TM) (0.42 +/- 0.08 N) the lowest. Sofreliner Tough M, in all incubation periods was the least toxic with significant differences compared to all other materials (P<.05). Coe-Comfort(TM), Coe-Soft(TM), and Sofreliner Tough M did not show any significant differences within their material group for all incubation periods.
CONCLUSION
This in vitro study revealed that aging can affect both the tear strength and cytotoxicity of soft denture materials depending on the composition.

Keyword

Soft liner; Tear strength; Thermocycling; Cytotoxicity; L929 mouse fibroblasts; XTT Assay

MeSH Terms

Aging*
Americas
Animals
Dentures*
Fibroblasts
Fungi
Mice
Sodium Chloride
Stainless Steel
Sodium Chloride
Stainless Steel

Figure

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  Fig. 1 Stainless steel mold for the tear strength test specimen fabrication.

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  Fig. 2 Stainless steel mold for cytotoxicity test specimen fabrication.

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  Fig. 3 Mean tear strength values for non-thermocycling, 1000, and 3000 cycle group. *significant difference (P<.05).

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  Fig. 4 Percentage of material cytotoxicity at 0 h, 24 h, 48 h and 72 h incubation period. CC: Coe-Comfort™, CS: Coe-Soft™, SR: Sofreliner Tough M, VG: Visco-gel. *significant difference (P<.05).

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