Tooth resorption part II - external resorption: Case series
A 19-year-old female patient presented to the department with a chief complaint of discoloured anterior teeth. The patient had completed her orthodontic treatment about 1 year back and had also undergone an orthognathic surgical procedure. On clinical examination, teeth # 7, 8, 9 and 10 displayed a yellowish brown discoloration. Grade I mobility was evident in teeth # 7 and 10 and grade II mobility in teeth 8 and 9. On percussion teeth #8 and 9 gave a typical metallic sound as compared to adjacent teeth. An unsuccessful attempt at access cavity preparation was detected on the palatal aspect of tooth #9. Teeth #8 and 9 failed to respond to thermal and electric pulp testing while teeth #7 and 10 responded within normal limits. A periapical radiograph revealed severe replacement of root structure of teeth #8 and 9 with alveolar bone with only half the root lengths persisting []. Some amount of root replacement was also seen in teeth #7 and 10. No canal spaces were evident in teeth #8 and 9; hence, no attempt was made to initiate any treatment. It was planned to take periodic periapical radiographs to assess the progression of replacement resorption in teeth #7 and 10. The patient was explained the poor prognosis but at the same time was reassured that there was no exigency in extracting the teeth. Composite laminate restorations were done for teeth #7, 8, 9 and 10 to mask the discoloration. A follow-up after 1 year revealed no significant increase in teeth mobility and resorption rate.\nExternal apical root resorption is commonly associated with orthodontic therapy due to certain biological factors (genetic susceptibility, systemic diseases associated with phosphorous-calcium metabolic alterations, medication intake) and mechanical factors (tooth movement type, orthodontic force magnitude, duration and type of force).[] Hence, it is essential to take periodic periapical radiographs during treatment.[] When root resorption is detected during active treatment, a decision must be made as to whether to continue, modify or discontinue the treatment.[] Luxation injuries are reported as the principal cause of replacement resorption.[] In this case orthodontic therapy was probably the etiologic agent which also initiated calcific metamorphosis in teeth #8 and 9. Replacement resorption is a continuous process whereby the tooth is gradually replaced by bone.[] Teeth undergoing this form of resorption, have a characteristic metallic percussion sound[] as was observed in this case. There is no known treatment for this type of resorption[] though unsuccessful attempts at Ca(OH)2therapy to arrest the resorption have been tried.[] If the teeth are in a satisfactory position, there is no urgency for tooth replacement because the replacement usually progresses at a slow rate ranging from few months to years. This provides time for the patient to be mentally and financially prepared for the treatment planned by the clinician.[]