National Health Care Systems Inc.: The Irvine-based...

National Health Care Systems Inc.: The Irvine-based prepaid dental plan operator said continued marketing efforts resulted in significant improvement in both revenue and net income for 1989. Net income rose to $179,381 from $57,277 for 1988. The figures included extraordinary gains of $81,183 in 1989 and $32,899 in 1988. Revenue increased 84% to $9.4 million from $5.1 million.