Ounsi et al
Figure 3: Extrusion of tooth #61 and follow-up root canal therapy treatment in an 18 months old child.
can later evolve into a cystic lesion is possible31, hence the necessity of follow-up sessions and control x-rays at 1,3,6 months then 1 year.
Pulpectomy When the tooth cannot be treated by pulpotomy or in certain failing pulpotomy cases, pulpectomy is the last resort before extraction.
To ensure the success of the root canal treatment on deciduous teeth, the practitioner must be familiar with the mode of formation of their roots as well as the variations that might occur in their root canal system. Root genesis is the same as for permanent teeth. The epithelial dental organ forms Hertwig’s epithelial sheath that in turn will initiate root formation by creating a tube prefiguring each root. During this stage, the apical foramen of the tube is delimited by the epithelial diaphragm. When root length is reached, the tube disappears but dentin apposition continues from the root canal side and contributes to the formation of the root canal system and apex closure. Radicular genesis is complete 3-4 years after tooth eruption. The roots of deciduous teeth are more divergent then that of their permanent counterparts which makes space for the bud of the permanent tooth.
The deciduous tooth is unique inasmuch as its roots start to resorb as soon as their edification is completed. At this stage, the shape and volume of the canal correspond approximately to the external shape of the root. The phenomena of radicular resorption and dentine apposition on the surface of the canal modify considerably the aspect and the number of canals. It should be stressed that most variations are in the buccolingual direction and that radiography only show mesiodistal anatomy. Hence the position of the main apical foraminae that is located at the root vertex may often be more coronal. This anatomophysiological characteristic is the cause of radiographic working length errors that can lead to overextension of the shaping instrumentation and overfills that may in turn harm the underlying bud of the permanent tooth. Radicular resorption of the deciduous tooth may create pulpoperiodontal communications far more extended then the apical foramen2.
Indications Pulpectomy is indicated in case of acute pulp inflammation leading to an uncontrollable hemorrhage after pulpotomy, in case of trauma on anterior primary or permanent teeth involving the pulp tissue, and in cases of necrosis and/or periodontal lesions32 (Figures 3-4).
Figure 4: Intrusion of 61 in an 18 months old child. Preoperative, one-year and 4-years follow-up radiographs.
INTERNATIONAL DENTISTRY SA VOL. 11, NO. 2