ABSTRACT
Objective:To compare the marginal and internal fit of selective laser melting(SLM)titanium crowns with lost-wax cast (LW)titanium crowns.Methods:Titanium crowns of 10 subjects were fabricated by SLM and conventional LW respectively(n =10).The marginal and internal gaps of the crowns were recorded with silicon film using a replica technique.Each silicon film was cut into 2 parts and the thickness of silicon layer was measured at ×100 magnification using a stereomicroscope,the data of marginal gap (MG)and internal gap(IG)were statistically analysed by ANOVA and SPSS statistical package version 17.0.Results:The MG (μm)of the titanium crowns of SLMgroup and LMgroup were 90.67 ±14.7 and 94.77 ±21.9(P 0.05),respectively.Conclusion:The marginal fit of the SLMcrowns is better than that of the LW ones,and is significantly smaller than 120 μm of the clinical generally accepted standards.
ABSTRACT
Objective:To study the fit of pure titanium single crown fabricated by electron beam melting(EBM).Methods:Pure titanium crowns were fabricated by EBM,selective laser melting(SLM),CAD/CAM(R +K and DMG)and conventional lost wax technique(LW)respectively(n =5).Marginal and internal gap was copied by light-body silicone and measured using a digital mi-croscope .The data of marginal gap(MG)and internal gap(IG)were statisticaly analysed by ANOVA and SPSS statistical package version 17.0.Results:The MG and IG(μm)of pure titanium crowns in EBM group were 38.42 ±6.72 and 105.54 ±33.18,in SLMgroup 38.63 ±6.82 and 114.63 ±52.18,in DMG CAD/CAMgroup 26.18 ±4.36 and 102.18 ±40.81,in R +K CAD/CAM group 26.98 ±4.44 and 102.24 ±25.30,in LW group were 42.61 ±5.73 and 102.98 ±45.67,respectively.The marginal fit of the EBMgroup was significantly smaller than 120 μm of the generally accepted clinical standards.In the 2 CAD/CAM groups the MG was smaller than that of other 3 groups(P 0.05).Conclu-sion:The marginal fit of titanium single crown fabricated by EBMis similar to that by SLM,better than that of LW and inferior than that of CAD/CAM.The internal fit of the crowns made by the 5 systems is similar.