Maintaining an ideal hardness value during the long term use of soft liner is very difficult, because soft liner material will lose some \nof its components and gain others, this will adversely affect its properties. The aim of the current study was to evaluate the effect \nof virgin coconut oil addition on the hardness of heat-cured acrylic based soft denture liner material. In addition, to investigate the \nwettability of the material after this incorporation. Both investigations were conducted at different periods of time. \nMaterial and method: one hundred eighty samples were prepared by the addition of 1.5% and 2.5% (by volume) of virgin coconut \noil into acrylic-based heat cured soft denture lining material. The study samples were divided into two groups (90 samples for \neach group) according to the conducted test; hardness and wettability tests. Then each group was further subdivided into three \nsubgroups (control 0%, 1.5% and 2.5%) according to the concentration of the incorporated coconut oil (n=10 samples for each \nsubgroup). Each group was assessed at different time intervals (1 day in distilled water, 14 and 30 days in artificial saliva), ten \nsamples were used for each time interval. Fourier transform infrared analysis was used to detect if there is any chemical reaction \nbetween soft lining material and coconut oil. \nResults: Shore A hardness test demonstrated a reduction in the mean value of hardness after adding 1.5% and 2.5% coconut \noil in comparison to the control group, this reduction was highly significant after 24 hours incubation in distilled water. The \nresults revealed a fluctuating behavior at different time intervals in which the values showed an increase followed by a decrease \nin the hardness after incubation in artificial saliva for both 2 and 4 weeks. Regarding the wettability test, the results revealed a \nreduction in the contact angle values after 24 hours and 2 weeks of incubation intervals, this reduction was highly significant for \nthe 1.5% group (p<0.01). While after 4 weeks of incubation, the mean values of contact angle of the experimental groups were \nincreased. Conclusion: Virgin coconut oil was successfully incorporated into the soft denture liner and revealed an improvement \nin the material softness and wettability.
Authors: Bushra M Alamen, Ghassan Abdul-Hamid Naji, Mohammed A. Alsmael
Publish Year: 2020
