Multiple external root resorption. Case report

Multiple external root resorption. Case report U. R. Darbar, BDS, FDSRCS(Edin)* C. B. G. Jenkins, BDS, MDS, PhD, LDS, FDSRCSt z zyxwvut zyxwvut zyx z zyxwvu zyxwvut Case report A 35 year old Caucasian man was referred by his Abstract general dental practitioner to the Dental Hospital with evidence, on bitewing radiographs, of resorpA case of a patient with multiple external root resorp tion affecting principally the molars and premolars tion affecting his lower molar teeth. There was no is described. This case is unusual in that although discomfort from any of these teeth. Medically he both right and left molar and premolar teeth are was fit and well with no history of any illnesses, involved, the resorption is worse on the left side and and there was no relevant family history. Previous affects only the distal roots of the molars. dental history, in addition to routine dental care, included orthodontic treatment with a removable (Received for publication April 1992. Accepted July appliance to retract the upper canines when he was 7 992.) 15 years old. No history of previous trauma to the teeth was obtained. Introduction Clinical examination showed an extensively restored Resorption is defined as the physiological or pathodentition and, periodontally, no pocketing, mobility logical dissolution of mineralized tissue by osteoclasts or bleeding on probing were present, even though or osteoclast type cells.’ External root resorption is the bitewing radiographs sent by the practitioner initiated in the periodontium and usually affects revealed sub-gingival calculus. Occlusal examineither the apical portion of the root, or the cementoation showed no premature contacts or interferences. enamel junction. Various authors have discussed All the teeth gave vital responses to ethyl chloride. resorption affecting the cemento-enamel j ~ n c t i o n . ~ . ~ The initial bitewing radiographs taken by the In the apical type, gradual shortening of the root practitioner revealed marked apical resorption with occurs giving the apex a rounded appearance. The loss of about half of the length of the distal roots resorption may arrest spontaneously> Causes impliof 36, 37. However, repeat bitewing radiographs cated for apical external root resorption include six months later, taken with a slightly altered film physiological tooth movement during eruption, presposition, showed no obvious advance of the condisure from unerupted teeth, cysts or invading tion but the 46 distal root was also seen to be neoplasms, inflammation, reimplantation, trauma, affected (Fig. la, lb). and orthodontic treatment.’ Idiopathic resorption is A panoramic radiograph was taken at the patient’s a term used when no specific aetiology can be found? first visit to the hospital, twelve months after the Shafer, Hine and Levy’ state that resorption may initial bitewings (Fig. 2). This showed there was be related to systemic disorders, the most obvious extensive resorption of the roots of 24, 25, 27, 28 being some form of endocrine disturbance, and and slight resorption of 17 and 38. hypoparathyroidism, hypothyroidism and Paget’s Investigations undertaken included estimates of disease have been implicated.8 serum calcium, phosphate, alkaline phosphatase, full blood count and liver function. All these were within normal limits. Thyroid function tests were also within normal limits. *Formerly Registrar in Restorative Dentistry, Bristol Dental Follow-up radiographs, six months after the Hospital. patient first attended the hospital showed no tConsultant Senior Lecturer in Conservative Dentistry, Univerapparent progression of the condition. sity of Bristol. Key words: External root resorption, case report. ~ _____ Australian Dental Journal 1993;38(6):433-5. 433 zyxwvutsrq zyxw Fig. la. - Initial bitewing radiographs showing resorption affecting 36, 37. Fig. lb. - Bitewing radiographs taken six months later revealing resorption also affecting 46. Discussion In the present case, no specific aetiology was found. All the teeth showing resorption were vital and hence the likelihood of inflammatory periapical pathology as a cause is remote. No positive results were obtained for tests of either systemic or endocrine disorders, thus ruling these out. The pattern of resorption affecting the premolar and molar teeth in the case presented can sometimes be seen following orthodontic treatment. Sjolin and Zachrisson in 19739 showed that resorption following orthodontic treatment is usually most conspicuous in the apical area resulting in shortening of the roots. It has also been shown that loss of an entire distobuccal root can occur during distal movement of teeth undergoing orthodontic treatment. The extent of the resorption in such cases would appear to be dependent on the magnitude and duration of the force applied." The most severe apical resorption has been associated with treatment using fmed appliances. However, it has been shown that after only 10 days of orthodontic movement, the pressure side of teeth showed the beginnings of the resorption process." Although the resorption pattern in this case superficially resembles that following orthodontic treatment, it was felt that this was an improbable aetiology for several reasons. First, there is no history of any appliances used to move the mandibular teeth. Secondly, it would seem likely that treatment received for retraction of the canines would have involved some force being exerted to the anterior teeth and these teeth do not show any signs of resorption. Thirdly, the lower left wisdom tooth also shows blunting of the apex. This tooth would not have been involved in the orthodontic treatment received. Lastly, equal forces would have been applied to both the right and left sides of both arches, but the left side appears to be affected more. In view of these points, it has been concluded that the orthodontic treatment is very unlikely to have caused the resorption. One other explanation that must be considered is a genetic predisposition which caused shortening of the roots. However, no other member of the family has been affected in a similar manner. Lind in 1973" documented cases in children where both centrals were affected together and symmetrically and cited similar observations in Japanese chil- zyxwvuts 434 Australian Dental Journal 1993:38:6. Fig. 2. -Panoramic radiograph showing full extent of resorption. dren.13 These cases have been given the title ‘short root anomaly’. The lack of further documentation of such cases was supported by the theory that these conditions had been misdiagnosed as resorption. However, it was felt that the present case did not fall into the ‘short root anomaly’ category. Other factors implicated in developmentally short roots include irradiation therapy,14 systemic diseases, for example, renal disea~e,’~ Stevens Johnson syndrome16 and inherited conditions, for example, dentinal dysplasia” which might occur during root development. These, however, can be excluded as the patient has no history of such episodes and all roots of affected teeth would have been shorter, not just isolated roots. Thus, in the absence of any attributable cause of resorption or any evidence that the roots were developmentally short, a diagnosis of idiopathic resorption appears appropriate. Clinical management of this case will involve careful and regular observation long term. No invasive treatment such as endodontics using calcium hydroxide is indicated as the condition is asymptomatic and now appears to be static. 4. Yusof WZ, Ghazali MN. Multiple external root resorption. J Am Dent Assoc 1989;118:453-5. 5. Feiglin B. Root resorption. Aust Dent J 1986;31:12-22. 6. Belanger GK, Coke JM. Idiopathic external root resorption of the entire permanent dentition. J Dent Child 1985;52: 359-63. 7. Shafer WG, Hine JK, Levy BM. A textbook of oral pathology. 4th edn. Philadelphia: Saunders, 1983. 8. Pankhurst CL, Eley BM, Moniz C. Multiple idiopathic external root resorption. Oral Surg Oral Med Oral Pathol 1988;65:754-6. 9. Sjolin T, Zaduisson BU. Periodontal bone support and tooth length in orthodonticallytreated and untreated persons. Am J Orthod 1973;64:28-37. 10. Langford SR, Sims MR. Upper molar root resorption because ofdistal movement. Am J Orthod 1981;79:669-79. 11. Goultschin J, Nitzan D, Azaz B. Root resorption - review and discussion. Oral Surg Oral Med Oral Pathol 1982;54: 586-90. 12. Lind V. Short root anomaly. Scand J Dent Res 1972;80: 85-93. 13. Ando S, Kiyokawa K, Nakashima T, er al. Studies on the consecutive survey of succedaneous and permanent dentition in the Japanese children. Pt 4. Behavior of short rooted teeth in the upper bilateral central incisors. J Nihon Univ Sch Dent 1967;9:67-82. 14. Pietokovski J, Menczel J. Tooth dwarfism and root underdevelopment following irradiation. Oral Surg Oral Med Oral Pathol 1966;22:95-9. 15. Postlethwaite KR, Hamilton M. Multiple idiopathic external root resorption. Oral Surg Oral Med Oral Pathol 1989; 68:640-3. 16. De Man K. Abnormal root development probably due to erythema multiforme (Stevens Johnson syndrome). Int J Oral Surg 1979;8:381-5. 17. Per1 T, Farman A G. Radicular (type 1) dentin dysplasia. Oral Surg Oral Med Oral Pathol 1977;43:746-53. zyx zyxwv zyxw zyxwvut zyxwvutsrqp zyx Acknowledgement The authors would like to express thanks to Dr J Eveson for his advice and assistance with this case. References 1. Cheshire PD. The diagnosis and treatment ofdental resorption - a review. J Paed Dent 1987;3:75-80. 2. Hopkins R, Adams D. Multiple idiopathic root resorption of the teeth. Br Dent J 1976;146:309-12. 3. Lydiatt DD, Hollins RR, Peterson G. Multiple idiopathic root resorption: diagnostic considerations. Oral Surg Oral Med Oral Pathol 1989;67:208-10. Australian Dental Journal 1993;38:6 Address for correspondence/reprints: Department of Periodontology, Eastman Dental Hospital, 256 Gray’s Inn Road, London WClX 8LD, UK. 435