Review of pathologic root resorption

Root resorption is a rare occurrence in permanent teeth. Unlike bone that undergoes resorption and apposition as part of a continual remodeling process, the roots of permanent teeth are not normally resorbed. Only resorption of primary teeth during exfoliation is considered physiologic. Dental resorption occurs in the special conditions such as truma, infection, stress and dental treatments. However, sometimes a specific reason cannot be found (idiopathic). Two conditions are necessary for resorption occurrence: 1. Protective surfaces of tooth damage 2. Presence of inflammatory stimuli Dental resorption is divided into two groups of internal and external. External resorption Includes: 1) Localized or diffused damage of the root surface 2) inflammation-related injury of the root because of the pressure, pulpal and cervical stimulation. Internal resorption can rarely occur in permanent teeth and the presence of granulation tissue in pulp or missing of odontoblastic layer and predentin may be the reason. Dental treatments that cause root resorption are orthodontics, surgery, bleaching, etc. The most common types of resorption after bleaching are cervical external resorption and internal resorption (rarely). This phenomenon mostly happens when the clinician uses heat-cure materials. For each skillful dentist it is necessary to have enough information about the etiology, diagnosis and treatment plan of different types of dental resorption.