Dentists and maxillofacial surgeons may occasionally encounter various dental anomalies in number, shape, size, and eruption. One such anomaly is dilaceration of the root. The term "dilaceration" refers to an angulation, or sharp bend or curve, in the root or crown of a formed tooth [1].

(Figure 1A, 1C and 1E) show micro-computed tomographic images representing teeth with root dilaceration (indicated by arrows). (Figure 1B, 1D and 1F) show the three-dimensional root canal morphology of each tooth, confirming that the root canal morphology is also dilacerated.

Traumatic injuries to the primary teeth can result in a wide range of anomalies in the permanent successor teeth. Dilaceration is thought to be due to trauma during the period in which the tooth is forming, with the result that the position of the calcified portion of the tooth is changed and the remainder of the tooth is formed at an angle [2]. Intrusive trauma to the primary teeth is often associated with developmental anomalies in the permanent successors. The prevalence of intrusive trauma to the primary incisors varies from 4.4–22% and the resulting developmental anomalies in the permanent incisors range from 12–74% [3].

Teeth with dilacerated roots pose a challenge to dentists. The root canal anatomy is complex (Figure 1), and dilacerated roots frequently present problems if the tooth requires extraction. Additionally, failure to recognize the curvature of the dilacerated root is one factor contributing to the higher incidence of failure of endodontic treatment in these teeth. To view the root canal morphology in three dimensions, computed tomography produces high-resolution images. Regarding as radiation exposure, the measured doses for the scans do not cause any radiation damage [4]. Furthermore, it has been reported that conventional micro-computed tomography usually does not reach the risky dose level, while classical synchrotron imaging can degrade a DNA significantly [5].

Knowledge of tooth morphology and root canal anatomy in three dimensions is essential for successful treatment of teeth with dilacerated roots. Computed tomography images are useful guides for the successful treatment of anomalies such as root dilaceration.

Keywords: Teeth, Root, Dilaceration, Micro-computed tomography

We would like to acknowledge all the staff members who were involved in the care of the patients.

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