<prompt> Purpose of liners and bases isare:Pulp protection from thermal and chemical agentsPulp protection from mechanical and electrical agentsPulp medicationAll of the above  <response>: Many restorative dental materials that provide excellent properties for the bulk of a dental restoration may not protect the dental pulp during setting or during cyclic thermal or mechanical stressing. Pulpal protection requires consideration of:Chemical protection.Electrical protection.Thermal protection.Pulpal medication.Mechanical protection. Liners and bases are materials placed between dentin and sometimes pulp and the restoration to provide pulpal protection or pulpal response. 