OBJECTIVEThe aim of the study was to detect the expression of Ki67 and P53 proteins in the gingival tissue before and after wearing three kinds of dental casting alloy crowns.

METHODSThe three kinds of dental casting alloys (58% golden alloy, NiCr alloy, NiCr alloy excluding Be) were used to make full crowns for 3 dogs in each group. Another 3 dogs were taken as control. The immunohistochemistry Envision method was used to measure the expression of Ki67 and P53 proteins in the gingival tissue before wearing the crowns, 2 weeks, 1 month, 2 months, 3 months after wearing the crowns.

RESULTSThe expression of Ki67 and P53 proteins in gingival tissue increased 1 month after wearing NiCr alloy and NiCr alloy excluding Be, then decreased gradually. And the expression of Ki67 and P53 proteins in 58% golden alloy group was similar to that in control. No pathological change was observed in all samples.

CONCLUSIONTwo kinds of NiCr alloy crowns both can increase the expression of Ki67 and P53 proteins in gingival tissue, but 58% golden alloy crowns can not. So compared with NiCr alloy crowns, 58% golden alloy crowns have better biological properties. And none of three kinds of dental alloy crowns may induce long-term abnormal proliferation in gingival tissue.