PRATIQUE CLINIQUE FORMATION CONTINUE TREATMENT OF AN INTRA-ALVEOLAR ROOT FRACTURE BY EXTRA-ORAL BONDING WITH ADHESIVE RESIN Gérard Aouate When faced with dental root fractures, the practitioner is often at a disadvantage, particularly in emergency situations. Treatments which have been proposed, particularly symptomatic in nature, have irregular long-term results. Corresponding author: The spectacular progress of bonding Gérard Aouate materials has radically changed treatment 41, rue Etienne Marcel perspectives. 75001 Paris Among these bonding agents, the 4- META/MMA/TBB adhesive resin may show affinities for biological tissues. It is these Key words: properties which can be used in the horizontal root fracture; treatment of the root fracture of a vital adhesive resin 4-META/MMA/TBB; tooth. pulpal relationship Information dentaire n° 26 du 27 juin 2001 2001 PRATIQUE CLINIQUE FORMATION CONTINUE “Two excesses: excluding what is right and only admitting In 1982, Masaka, a Japanese author and what is right”; Pascal, “Thoughts”, IV, 253. clinician, treated the vertical root fracture of a “I ask your imagination in not going either right or left”; maxillary central incisor in a 64 year-old Marquise de Sévigne, “Letters to Madame de Grignan”, woman using an original material: adhesive Monday 5 February, 1674. resin 4META/MMA/TBB (Superbond®). The tooth, treated with success, was followed for 18 acial trauma represents a major source years. of injury to the integrity of dental and Extending the applications of this new material, periodontal tissues. The consequences Masaka further developed his technique in 1989 on dental prognoses are such that they with the bonding together of fragments of a have led some clinicians to propose fractured tooth after having extracted it and, Ftreatment techniques for teeth which, then, subsequently, re-implanting it. otherwise, might have been condemned to This last procedure, in addition to the extraction extraction. and joining together of the fragments, also We will not discuss the related manifestations gave the author an opportunity to rotate the of dento-alveolar trauma but will focus our root 180˚ around its longitudinal axis. This attention on high dental root fractures. positioned the destroyed tissue (periodontal When dealing with the treatment of horizontal ligament, alveolar bone) facing healthy tissue root fractures (HFR), the consultation results, (alveolar bone, periodontal ligament) (Masaka, and, indeed, most of the available literature, 1982; 1985; 1995; Masaka and Irie, 1998). provide the practitioner with a great variety of In 1989, after a long period during which there treatment options, most of which offer uneven was much documented use of Superbond results which are also short-term. Each author applied to the dentin of vital teeth, Masaka offers cautious progress, but the general performed a direct pulp cap (Masaka, 1991), consensus is that there is no consensus. and ascertained the preservation of pulpal vitality. These results were confirmed by other Proposed treatments all tend towards the same authors who concluded that the adhesive resin goal: eliminate the fracture line, either by 4-META/MMA/TBB displays a strong affinity restorative dentistry techniques or by with the pulp with which is it capable of techniques of partial root resection or, creating a biological joint (Inoue and Shimono, ultimately, total amputation (extraction). 1992; Miyakoshi et.al., 1994). The 4- META/MMA/TBB is a chemically polymerized Techniques which are devoted to preserving resin which achieves, at the same time, a the tooth fragments have used various liaison with the dentin via a smear layer methods of joining them together, such as: (Nakabayashi et.al., 1991; Nakabayashi and • cyanoacrylic glue (Oliet, 1984), Pashley, 1998) and with the metallic or ceramic • composite materials (Hasegawa et.al., 1988; prosthetic structure. Munksgaard et.al., 1991; Serfaty, 1991), Among its other properties, this material also • glass ionomer cements (Trope and achieves a high level of dentin and enamel Rosengerg, 1992; Stewart, 1990) adhesion (17 and 15 Mpa respectively), as well • attempts at laser dental fusion (Zakariasen KL as a remarkable impermeability (the best et.al., 1988), results when compared to similar materials • close approximation of the separated tested). (Cooley et.al., 1991; Nakabayashi and fragments and their subsequent Saimi, 1996.) immobilization in the young patient (Michanovicz et.al., 1978). Therefore, it would seem that, when The question of root fracture treatment, considering the 4 META/MMA/TBB adhesive therefore, remains a challenge as long as a resin: definitive treatment model is still uncertain and • its adhesion to the dental substrata, undetermined. • the relative absence of cytotoxicity (Kamal 2002 Information dentaire n° 26 du 27 juin 2001 Fig. 1: The patient, Mrs. B., presented for emergency consultation on March 22, 2000. Five hours previously, she had suffered a fall, without any memory of specific details, preceded by a loss of consciousness. Fig. 2: Tooth #11 seems to be the only tooth adversely 12affected as a consequence of this facial trauma. It is the only mobile and displaced tooth. The clinical signs associated Table 1 History of with the radiographic The use of adhesive resin 4-META/MMA/TBB is indicated the trauma examination and pulpal in the following clinical situations: The patient fell, after vitality tests of neighboring teeth eliminated them • orthodontic bondings, either surgical or non-surgical; a momentary loss of from immediate inclusion • the stabilization, by bonding, of a mobile tooth in consciousness in our treatment plan. emergency treatment; caused by self- Periodic examination will be necessary for these • the bonding of cast splints, prosthetic restorations, and medication of a adjacent teeth, the object inlays; contra-indicated being to maintain their • the repair of fractured cosmetic elements; substance. On the tissular integrity. A rapid • the reinforcement of roots which have been extremely and complete diagnosis telephone, the must be reached, based on weakened by a bonded casting; 3 patient described whether we are dealing • the preservation of roots which have been vertically with precision the with a non-fractured tooth fractured and of roots which have iatrogenic perforations; (tooth, root) luxated out of type of injury sustained some hours before. the alveolus, or with a root • indirect and direct pulp capping. She was instructed to come to our office fracture with displacement immediately. The circumstances of the of the fragment(s). In the case of an intact tooth accident, the eventual possibility of associated (non-fractured), the manifestations, as well as an evaluation of the emergency treatment will prior condition, are absolutely necessary in consist of the alveolar repositioning of the et.al., 2000), order to not risk overlooking any major traumatized tooth, then • its biocompatibility, associated pathology. the installation of a means of non-rigid stabilization. are the qualities of the material which are the Notice the spontaneous most significant. gingival hemorrhage at the Examination and Diagnosis marginal gingiva. The clinical applications of 4-META/MMA/TBB Examination and diagnosis must be Fig. 3: The retro-alveolar adhesive resin, (Table 1), have broadened accomplished rapidly and in a manner which radiograph confirms the adequately determines the degree of findings of the clinical therapeutic possibilities, and the abundant examination and permits documentation associated with the precepts involvement of the superficial and deep dental- us to propose the diagnosis of root fracture set forth by Masaka (Masaka N., 2000), have periodontal tissues (Fig. 2). Radiographs allow us to establish a positive with luxation and led us to perform and present the following extrusion of the coronal diagnosis and to ascertain a differential clinical case. fragment. Radiographic diagnosis: root fracture with displacement of examination does not only one or of several fragments; single root reveal fracture of the alveolar bone. The apical Clinical Case fracture or multiple fractures; fracture limited root fragment is in its to one tooth or to several teeth; nature of the original position, which Mrs. B, 49 years of age, presented for injury in terms of subluxation (no signifies that the vascular- emergency consultation after a traumatic nerve bundle at the apex displacement of the fragments) or luxation dental injury (Fig. 1). has not suffered severe (displacement of the fragments) (Fig. 3). bruising. Information dentaire n° 26 du 27 juin 2001 2003 PRATIQUE CLINIQUE FORMATION CONTINUE 4 5 Fig 4: The classic approach, which is to manually reposition the displaced fragment before stabilizing it, is not the approach which we have used. The reason for this is that an incorrect repositioning may give rise to the interpositioning of fibrous tissue. Our treatment choice is based on the direct visual re-assembly of the tooth fragments by bonding with the 4-META/MMA/TBB resin adhesive (Superbond ®). After local anesthesia, we chose to save the first fragment of tooth, examine it. Fig. 5: ……clean the alveolus with gentle rinsing, and then extract the apical fragment. Fig. 6: The bonding protocol must scrupulously respect the manufacturer’s instructions. The coronal piece of tooth must undergo scaling without polishing as well as mechanical bacterial decontamination with air- 6 abrasion, carefully avoiding the apical vascular-nervous bundle.