INBDE (Integrated National Board Dental Examination) 2026 – 400 Free Practice Questions to Pass the Exam

When a base is needed in dentistry for metal restoration, it is to provide thermal insulation for the tooth and to protect the pulp from any harmful chemical reactions with the dental material. None of the other options listed require a base for these purposes. After a tooth extraction, a socket dressing may be used to protect the area while it heals but this serves a different purpose than a base for metal restoration. Bases are typically not used before placing a dental crown unless there is an underlying cavity or fracture that needs to be protected. In a root canal treatment, the focus is on cleaning and disinfecting the root canal space, so a base is not typically used in this procedure. Therefore, the correct answer is A When a liner is used for metal restoration.