FIGURE 1--The patient presented with suppuration and bleeding at 21. She was previously diagnosed with an "enamel pearl". The pati...
FIGURE 2--Radiographic examination of 21 revealed an opaque outline (arrow) ad raised the existence of a possible union between th...
FIGURE 3--The flap was exposed and the supernumerary tooth revealed. Of note is calculus (arrows) and loss of the buccal plate of ...
FIGURE 4--The supernumerary tooth was removed with a Stryker handpiece and multifluted bur. The area was smoothed with a back-acti...
FIGURE 6--An osteoconductive bone additive one added to the area to reconstruct the defect and the buccal wall and an a collagen m...
FIGURE 7--The area was sutured, however the edges of the incision were difficult to reposition after the necrotic tissue was excis...
FIGURE 8--Healing at two weeks post-surgery. Some recession was evident.
FIGURE 9--Four months post-surgery -- the tissue maturation continued, probing was within normal limits, however, some bleeding up...
Concrescence: A Cemental Union Between a Supernumerary Tooth and a Central Incisor
Altered morphology of teeth can be due to perturbations in the genetic process of odontogenesis. Developmental alterations in tooth shape include germination, fusion and concrescence. Ectopic enamel formation including enamel pearls and cervical enamel projections are associated with compromised areas of periodontal attachment. The restorative, orthodontic, endodontic and periodontal treatment planning of teeth so affected can be challenging. To prevent significant periodontal attachment loss, areas exhibiting developmental alterations in morphology must be thoroughly instrumented by the dental professional as well as maintained meticulously by the patient. Removal of ectopic enamel formations or separating teeth with altered morphology can be complicated given the possibility that vital pulp tissue may be encountered. This often requires a multidisciplinary approach involving several specialties. This paper reports a rare case of a concrescence between a central incisor and a supernumerary tooth and the management of this anomaly from a periodontal perspective in the esthetic zone.
CASE REPORT
A 54-year-old woman with a history of multiple sclerosis, a 10 pack per year smoking history and severe dental anxiety was referred for an implant at 21. She was previously diagnosed with an "enamel pearl" on the facial aspect of 21 which was associated with recession, deep pocketing and chronic drainage from the buccal gingiva. The patient was not at all concerned by the situation as she reported the 21 area was comfortable, functional and esthetically satisfactory (Fig. 1). She reported that her dentist suggested the tooth be removed in the 1970s and although this recommendation was not followed, she was pleased to report, over the years, it had not changed noticeably to her.
The clinical examination of tooth 21 revealed no mobility, however, periodontal attachment loss with a maximum probing of 12mm at the distal and mesial facial line angles was measured. A fistula on the facial gingiva released yellow exudates upon probing. Bleeding on probing was also evident and there was generalized root roughness. Radiographic examination revealed a radio-opaque structure which was superimposed over the pulp chamber of 21 (Fig. 2). No periapical radiolucency was noted at 21 and there appeared to be localized bone loss on the distal of 21. The diagnosis of an "enamel pearl" could not be confirmed clinically or radiographically and the differential diagnosis included a gemination, concrescence or dens invaginitus.
An exploratory surgery was recommended to visualize the extent of periodontal destruction and to determine the long-term prognosis of the tooth. During the process of achieving informed consent the patient was clearly advised of the possible need of endodontic therapy and that the tooth my be deemed unrestorable leading its removal.
Under intravenous sedation, the area was anesthetized and a full thickness flap was raised using a beveled releasing incision. The central incisor was exposed and a supernumerary tooth was revealed (Fig. 3). The supernumerary tooth was removed and the facial surface of 21 was decontaminated (Fig. 4). No pulpal exposure was achieved. The necrotic/granulation tissue was excised (Fig. 5) and the dearth of osseous volume was reconstructed with 0.5 grams Bio-Oss® (Osteohealth, Shirley, NY) mixed with autogenous bone (Fig. 6) and covered with a Bio- Gide® (Osteohealth, Shirley, NY) membrane. The tissues were sutured with 6-0 Seralon sutures (a non absorbable, monofilament polyamide) the area left to heal for two weeks (Fig. 7). Antibiotics and analgesics were prescribed.
The patient had an unremarkable recovery. Mild recession was noted at the post-operative visit (Fig. 8) as well as the 4-month follow up. Probing depths at six months post surgery were a maximum of 4mm on the disto-facial aspect of the tooth. The tooth had no mobility but exhibited recession that was a concern for the author (PCF), but not the patient.
DISCUSSION
Concresence usually involves the union, by cementum, of two fully formed teeth. This may occur during development "true concrescence" or after development "acquired concrescence".1 The mechanisms involved are unclear but it has been speculated that restriction of space during development, local infection, trauma and excessive occlusal forces may play a role in this anomaly. Both primary and secondary teeth may be involved, with the maxillary and posterior areas typically involved. The most common presentation is an impacted maxillary third molar with the second molar. 2
As far as we are aware, a concrescence between a central incisor and supernumerary tooth is previously unreported. Surgical division of teeth joined by cementum is not usually successful due to poor access to the area and complicated root structures. In the case presented above, the objective was to remove the supernumerary tooth without disturbing the pulp of the erupted permanent central incisor. This removal was facilitated by the loss of bone experienced by the patient after decades of a chronic localized periodontal infection.
The management of the tissues presented a challenge due to their fragile nature after years of draping the underlying infection and the supernumerary tooth. After the excision of the necrotic tissue, the area had to be further released to contain the grafting material in a tension free fashion. Harvesting a connective tissue graft and using this soft-tissue graft to augment the dearth of gingival tissue may have further improved the outcome.
CONCLUSION
The altered morphology of teeth provides yet another challenge to the clinician trying to maintain the periodontal health for the patient. Often, as in the case of cervical enamel projections, enamel pearls and concrescence, it is possible to successfully address these challenges surgically and improve the periodontal attachment for the patient, thus improving their oral health. Recognizing these challenges and then designing a treatment plan that addresses them adequately is essential in providing the best service possible to the patient.
Dr. Fritz is in private practice in Fonthill, ON. His practice focuses on implant surgery, periodontal medicine and hard and soft tissue reconstruction. He is the incoming president for the Ontario Society of Periodontists and is actively involved in continuing education for dental health professionals. www.drpeterfritz.com
Dr. Fielding is in private practice in Burlington, ON.
Dr. Ward is a tenured professor in the department of Nutritional Sciences, Faculty of Medicine, University of Toronto with an active research program in bone health. She is also a guest lecturer at the Faculty of Dentistry, University of Toronto.
REFERENCES
1. Neville BW, Damm DD, Allen CM, Bouquot JE, eds. Chapter 2: Abnormalities of the Teeth, In: Oral and Maxillofacial Pathology. W. B. Saunders Company. Philadelphia, PA. 1995 pp. 65.
2. White SC, Pharoah MJ, eds. Chapter 17: Dental Anomalies, In: Oral Radiology, Principles and Interpretation. 4th edition. Mosby Inc. Toronto, ON. 2000 pp. 311.
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The restorative, orthodontic, endodontic and periodontal treatment planning of teeth so affected can be challenging
