Clinical Case We will illustrate our thoughts with Arthurâ€™s case. He experienced a trauma involving his two permanent upper central incisors at the age of 8 Â˝. The accident involved pulp exposition on the two upper central incisors and the emergency treatment was not performed in good conditions on the day of the accident. The two central incisors became necrotic at the time where the root apexes were immature. Endodontic Treatment Doing endodontic treatment on teeth with an immature apex poses a real problem because there is no apical constriction. The clinician has the choice between 3 techniques. The oldest technique utilizes calcium hydroxide Ca (OH) as an intra-canal medication to stimulate apexification. This technique has a high success rate, around 95% (77 to 98% depending on the study7) but the technique as some drawbacks beginning with the time it takes to obtain some results (from 6 to 18 months) and with the numbers of visits involved. Also it is now known that prolonged use of calcium hydroxide lowers the resistance of the dentin to fracture and can compromise the life of the tooth at medium and long-term.8 Another technique consists in plugging the apex with MTA (Mineral Trioxide Aggregate). This technique allows the clinician to close the canal with gutta-percha in the same visit and has a high success rate, as shown in the first clinical studies available.9,10 The only drawback is the possibility of root fracture due to the tenderness of the dental walls. It is also still possible to stimulate apexification with a technique called revascularization. The idea is tempting since the clinician is trying to regenerate the pulp from periapical souche cells. Compared to other apexification techniques, this
last one allows the obtention of a real root growth in width an in length.11 We now have a few cases published in the literature and they are convincing, but the protocol of this technique has not reach a consensus yet.12 In regards to our patient Arthur, MTA was used by the treating clinician for the reasons we have stated above. At a second visit the root canal finished with warm gutta-percha after verification that the MTA had hardened. Composite restorations were done to assure a good coronal seal (Figure 2). Orthodontic Treatment The orthodontic treatment started two years after the accident, the patient was then 10 Â˝ years old. He had a large overjet and a class to Division I malocclusion with a retrusive mandible. The labial tipping of the upper incisors had those teeth in a position prone to a second trauma with the possibility of a root fracture which could have meant the loss of the two central incisors (Figure 3). The use of light forces allowed us to correct the malocclusion in a timely fashion (under 20 months), without doing any harm to the roots of the traumatize central incisors (Figure 4).
a b c Figure 3: Case for full orthodontic treatment: initial photograph in the vestibular view (a), left lateral view (b) and maxillary occlusal view (c).
Figure 3: During orthodontic treatment photographs (d, e, f): after removal of brackets and bonding of the retention wire (g, h, i).
Figure 2: Both upper central incisors were necrotic following a trauma: pre-op periapical x-rays (a), master cone of gutta-percha in the root (b), apical MTA seal on left central incisor (c), gutta-percha seal and temporary seal of the cavity (d),; apical MTA seal on right central incisor (e), gutta-percha seal and temporary seal of the cavity (f). (Curtesy of Dr. Caron) 12
Figure 4: X-ray follow-up of the maxillary incisors: periapical x-rays before treatment (a), during orthodontic treatment (b), after the bracket removal and bonding of the retention wire (c). IJO