Which glass ionomer type is specifically used to combat class 5 decay?

The correct choice for addressing class 5 decay is Type 2 glass ionomer. Class 5 cavities are typically located in the cervical areas of both anterior and posterior teeth, often due to decay or erosion. Type 2 glass ionomer is particularly formulated to have a higher strength and greater resistance to wear compared to other types, making it suitable for areas that endure greater functional wear during chewing and other dental activities.

Type 2 glass ionomer also has the added benefit of adhesive properties that allow it to bond well to tooth structure and release fluoride, contributing to additional protection against further decay. It enhances the overall longevity of the restoration in the specific situation of class 5 decay.

The other types of glass ionomer fulfill different functions; for example, Type 1 is primarily used for cementing purposes, Type 3 is intended for liners and bases, and Type 4 is not typically related to direct restorative applications. Thus, their characteristics do not make them suitable for the specific requirements of treating class 5 decay.