Tooth resorption part II - external resorption: Case series
A 20-year-old female patient undergoing orthodontic treatment was referred for the management of external resorption in teeth # 20, 21, apparent on the periapical radiograph. The patient was asymptomatic and the medical history was non-contributory. Past dental history revealed extraction of an impacted tooth that was present between the apices of teeth # 20 and 21, about 1 month earlier. Clinically, the teeth were noncarious and appeared normal. They responded to both thermal and electric pulp testing within normal limits. The apices of teeth # 20 and 21 showed irregular margins with loss of adjacent lamina dura on a periapical radiograph. A circular radiolucency was present in between the root apices that probably represented the space that was occupied by the crypt of the impacted tooth [].\nSince the patient was undergoing orthodontic treatment, all active forces were removed. Following access cavity preparations, the vital pulp tissue was extirpated and thorough debridement of the canal system was done to the working length with hand stainless-steel K-files upto size 45. The profuse bleeding from the canal especially on reaching the apical region was controlled with copious irrigation of 5.25% NaOCl. The canals were dried with paper points and Ca(OH)2 paste was placed in the canals as an intracanal medicament. The medicament was changed after every 15 days. Periodic radiographs were taken after every 1 month [–]. Orthodontic treatment was resumed after 3 months from the commencing of treatment as radiographic signs of healing were evident. Ca(OH)2therapy was continued for a period of 2 months further at the end of which complete periapical healing and normal root architecture of the root apices was evident []. Root canal obturation of both the teeth was then completed and a follow-up radiograph after 1 year shows maintenance of the restored root architecture [].\nExternal inflammatory resorption usually follows trauma or periodontal infections that can initiate an inflammatory response within the periodontal ligament.[] It could be a squeal to pressure induced by the crypt of an erupting/unerupted tooth, neoplasms or during orthodontic treatment.[] Excessive intrusive or tipping orthodontic forces can initiate an inflammatory response.[] In the above case, the pressure induced by the crypt of the impacted tooth coupled with the orthodontic treatment could have been the etiologic factors leading to resorption. External inflammatory root resorption usually occurs without any clinical symptoms and forms part of the periapical pathology associated with apical periodontitis.[] Placement of Ca(OH)2 intracanal medicament has been recommended for 6 to 24 months. It exerts an antibacterial effect and also increases the pH of dentin by the diffusion of hydroxyl ions through the dentinal tubules.[] It also induces the formation of a new cemental apical barrier thus preventing over-extension of the root filling material.[]