Fourcault process the pit must be "heated back" and then the process can continue anew. Glass chemistry has a huge impact on the process since it controls the melting, forming and annealing temperatures, liquidus temperature (point where various chemicals that make up the glass start to crystallize out of the glass) and rates of change of characteristics of the glass itself. Occasionally the ribbon will break or crack, leading to failure of the drawing process. Such breaks, known as "checks" can be alleviated by using proper operating parameters. Sometimes an expedient measure, using a portable source of heat, can be used to
Glass ionomer cement the physical shortcomings of the glass ionomer cements such as thermo-light curing(polymerization), or addition of the zirconia, hydroxyapatite, N-vinyl pyrrolidone, N-vinyl caprolactam, and fluoroapatite to reinforce the glass ionomer cements. Glass ionomers are used frequently due to the versatile properties they contain and the relative ease with which they can be used. Prior to procedures, starter materials for glass ionomers are supplied either as a powder and liquid or as a powder mixed with water. A mixed form of these materials can be provided in an encapsulated form. Preparation of the material should involve following manufacture instructions. A paper pad