[The clinical observation of tetracycline stained teeth covered by composite resin veneer induced of secondary gingivitis].

Using gingival index,sulcus bleeding index and plaque index of 765 tetracycline stained teeth covered by composite resin veneer after 1/2-3 years were observed.It was found that the incidence of gingivitis was over 60%.The reexamination after three months later showed that the three indexes were significantly improved by grinding teeth proper and teaching standard brushing method.