Study On Effect Of Masking Ability Of Silicone Rubber Prosthesis On Masking Materials

【Objective】To study effect of diffenent masking materials and different treatments on masking ability of silicone rubber prosthesis,relatively transparency change of silicone elastomer test pieces mingled in different proportions nano TiO₂ and effect of barrier of ultraviolet light(UVL) of test pieces added in different TiO₂,it offer theorial basis for clinical selection and colourity of prosthesis in maxillofacial region.【Material and Method】Different masking materials and nano TiO₂ after different treatments reshaped added to bicomponent silicone elastomer and agitated,evacuation and heated to solidification to make standard test pieces,then detect tristimulus values under standerd black and white backgrounds,Put different proportions nano TiO₂ after cladding with silicon and aluminum into silicone elastomer,agitated,evacuation and heated to solidification,then detect tristimulus values and reflectivity rate under black and white backgrounds;Put different kinds of TiO₂ into silicone elastomer.agitated,evacuation and heated to solidification,then detect transmissivity rate values of UVL.Transmission electron microscope(TEM) of JEM200CX analysis disposition of nanometer masking coloring particles in silicone elastomer before and after reshaping masking materials.Altraviolet spectrophotometer(UVspectrophotometer) of Lambda 19 integrating sphere detected effect of barrier of ultraviolet light(UVL).Experimental index are chromatic aberration value,reflectivity and transmissivity rate values of UVL,dividatured experimental group (EG),different kinds,different quality fraction.after different treatments masking materials in silicone elastomer as experimental group(EG) compare between two groups detecting masking ability and transmissivity rate of UVL;Different quality fraction nano TiO₂ with cladding silicone and aluminium as experimental group(EG) compare between two groups detecting relatively transparency.【Result】With different kinds of masking materials mingled in,discover chromatic aberration value of titanium white powder is smallest,with nano TiO₂ is highest;Diferent treatments have no effect on test pieces,with proportion fractions increasing,chromatic aberration value of TiO₂ with cladding silicone and aluminium is higher than test pieces of the other treatment;With proportion fractions of nano TiO₂ increasing,relatively transparence value decrease progressively,Yb/Yw value increase gradually.with thickness increasing, relatively transparence value have a relationship of inverse ratio,Yb/Yw value have a relationship of direct radio.l%chromatic aberration value and relatively transparencevaluerespectively16.2±0.03,9.81±0.01,4.75±0.01;0.025±0.001,0.037±0.003, 0.046±0.003.5%chromatic aberration value and relatively transparence value respectively 12.9±0.02,7.42±0.03,3.25±0.02;0.021±0.003,0.033±0.001,0.04±0.002.9%chromatic aberration value and relatively transparence value respectivelyl0.0±0.01,5.80±0.02, 1.75±0.03;0.013±0.002,0.027±0.002,0.035±0.001.13%chromatic aberration value and relatively transparence-value respectively 7.1±0.02,4.34±0.01,0.5±0.01;0.013±0.002, 0.027±0.01,0.035±0.002.Transmissivity rate of UVB different masking materials have no effect in UVB stage,but in UVA stage,transmissivity rate of UVA on nano TiO₂ with cladding silicone and aluminium nearly 0,other else is not.【Conclusion】In different kinds of masking materials,discover masking ability of test pieces with titanium pigment powder is weakest,with nano TiO₂ is strongest.Diferent treatments have no effect on test pieces in small proportion fraction,but with proportion fraction increasing,masking ability of nano TiO₂ with cladding silicone and aluminium is stronger than the other;After nano TiO₂ with cladding silicone and aluminium,with proportion fractions increasing,relatively transparence value decrease progressively.When 9%,the change of relatively transparence rate have no distinction,with proportions increasing;Under same proportion fraction,with thickness increasing,Yb/Yw value increased,relatively transparence rate descended notably.Under same thickness,with proportion fraction increasing,Yb/Yw value increased,relatively transparence rate decreased notably;Transmissivity rate of UVA different masking materials have no effect in UVA stage,but in UVB stage,transmissivity rate of UVA on nano TiO₂ with cladding silicone and aluminum nearly 0,other else is not.Barrier ability of UVL is higher than others.