The Inadequacy B and C of marginal seal were more prevalent for restorations without the additional marginal seal ( Group 1 ) : 18 of 28 total ( 64 % ) at 12 months with inadequacy B ; 19 of 25 total ( 76 % ) with inadequacy B and 16 total ( 100 % ) with inadequacy C at 18 months ; 9 of 17 total ( 53 % ) with Inadequacy B and 13 total ( 100 % ) with Inadequacy C at 24 months ; 12 of 17 total ( 70 % ) with Inadequacy B and 9 of 13 total ( 73 % ) with Inadequacy C at 36 months ; 14 of 24 total ( 58 % ) with Inadequacy B and 7 of 11 total ( 63 % ) with Inadequacy C at 48 months .