The difference between product-oriented marketing (also called product orientation) and market-oriented marketing (also called the market orientation) has to do with how the firm was making its profit and with what motivated the firm to create new products and/or refine existing products.
The product orientation focused on creating a high-quality product. The idea was that consumers would want the product so long as the quality was good. In health care, a hospital might simply work to increase the quality of care provided and to publicize that quality.
The market orientation is focused more on trying to chase the needs and wants of consumers. Firms find out what consumers want and try to create products that will fill those needs. A health care firm using this orientation might create a drug like Viagra or might pioneer new plastic surgery techniques that might appeal to consumers wishing to look younger.
The difference, then, is in what drives the firm's actions.