Journal of Indian Society of Pedodontics and Preventive Dentistry
Journal of Indian Society of Pedodontics and Preventive Dentistry
                                                   Official journal of the Indian Society of Pedodontics and Preventive Dentistry                           
Year : 2018  |  Volume : 36  |  Issue : 2  |  Page : 216--219

Aberrant root formation - An unreported complication of dental trauma

V Revathy, R Abirami, R Abharna 
 Department of Pedodontics and Preventive Dentistry, Tamil Nadu Government Dental College and Hospital, Chennai, Tamil Nadu, India

Correspondence Address:
R Abirami
No 9, Pink Avenue, Officers Colony, Padi, Chennai - 600 050, Tamil Nadu


Trauma and infection to immature teeth can result in a number of complications. Discontinuity in the formation of root is one such complication which has never been documented before. In the following article, a case report of this aberrancy which was observed in the root of a permanent central incisor, subsequent to a traumatic injury is discussed. In spite of this discontinuity, complete root formation and vital pulp were noted in the tooth. Since such a case has not been reported in literature till date, this complication is described and the possible cause of its occurrence is discussed in this article.

How to cite this article:
Revathy V, Abirami R, Abharna R. Aberrant root formation - An unreported complication of dental trauma.J Indian Soc Pedod Prev Dent 2018;36:216-219

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Revathy V, Abirami R, Abharna R. Aberrant root formation - An unreported complication of dental trauma. J Indian Soc Pedod Prev Dent [serial online] 2018 [cited 2022 Jan 16 ];36:216-219
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A fall or an injury can result in trauma to the anterior teeth. When trauma occurs in a developing tooth, it can result in certain additional complications including morphological alterations.[1] The type and extent of the complication largely depends on the stage of tooth development and the degree and direction of force.[2] This case report describes one such rare complication which occurred in the root of a permanent central incisor following a traumatic injury which took place during its development.

 Case Report

An 8-year-old female presented with the chief complaint of a small swelling in the left upper front tooth region which had been there for a week. On anamnesis, it was revealed that the patient had a traumatic injury 6 months ago. Past medical and dental histories were insignificant. On examination, patient had mixed dentition and all the teeth appeared normal for her age with no sign of fracture. There was a sinus opening in relation to the attached gingiva between the left upper central incisor (21) and lateral incisor (22) [Figure 1]. The tooth was non-tender on percussion and the soft tissues were non-tender on palpation. Thermal pulp vitality tests were inconclusive and hence were not relied upon because of the incomplete root development.{Figure 1}

To determine the source of sinus opening, a sterile gutta percha point was inserted into the sinus opening and an intraoral periapical (IOPA) radiograph was taken. IOPA radiograph revealed immature upper central incisors (11 and 21) with open apices but the source of infection could not be tracked conclusively [Figure 2]. Since the tooth was immature and less than two-thirds of the root development had taken place, a non-invasive symptomatic treatment involving conservative management was planned as any invasive treatment at that stage might hamper subsequent root development and hence appropriate crown root ratio might not be achieved. The patient was advised topical chlorhexidine gel and chlorhexidine mouth rinse for a period of 1 week. Patient was kept under regular observation and recall. When the patient was reviewed after a period of 1 week, she was completely free of symptoms. The sinus opening had healed completely with no pain. The patient was then recalled at regular intervals. No invasive treatment was done and the patient was kept under observation during these visits.{Figure 2}

The IOPA radiograph, taken at 1 year recall visit shown as [Figure 3], revealed root formation beyond the site of infection with a small discontinuity in relation to the middle third of root of 21. When the patient was recalled after a period of 3 years from the time of injury, the IOPA radiograph revealed complete root formation with apical closure in 21 but the discontinuity persisted [Figure 4]. Pulp vitality tests resulted in positive response in 21 and the patient was completely asymptomatic at the end of 3 years of follow up inspite of the break in the continuity of root in 21. This kind of discontinuity in root formation has not been named or reported in the literature as a complication of trauma in an immature permanent tooth. Patient is under follow up to study the health of the tooth with aberrant root formation.{Figure 3}{Figure 4}


Tooth root formation occurs as a result of well mediated interactions between the cells of Hertwig's epithelial root sheath (HERS) and the cells of dental papilla and dental follicle.[3] When the crown formation of tooth attains near completion, the HERS grows in an apical direction between the dental papilla and dental follicle. As it grows apically, the cells of the dental papilla adjacent to HERS get differentiated to form odontoblasts. The basement membrane acts as an inducer of odontoblast differentiation. HERS also secretes substances such as laminin, transforming growth factor-beta which cause differentiation of dental papilla cells to odontoblasts [4] which form the radicular dentin. If the continuity of HERS is disturbed, then the cells of the dental papilla will fail to get differentiated and hence dentin formation will be affected. Subsequently, the cementum formation will also be affected as HERS and root dentin play a pivotal role in cementum formation.[5]

Based on the physiology of root formation as explained above, a probable etiopathogenesis of the aberrant root can be given as follows. The traumatic impact could have caused localised death of dental papillary cells resulting in an inflammatory focus adjacent to 21. The inflammatory exudates produced could have drained resulting in sinus formation. The inflammation could have been severe enough to destroy the cells of the root sheath in that localised region. The resilient nature of the HERS [6] could have aided to complete the odontoblastic differentiation in the rest of the tooth root, explaining the completion of root formation in the other regions of the tooth root except the perforation where there is a lack of dentin and cementum.

Trauma to the tooth during the development can cause various morphological changes in the tooth root. [Table 1] lists the possible morphological alterations of the permanent tooth root due to trauma with selected articles. However such an aberrant root has not been reported yet. Discontinuity in the root formation as presented in this report is a possible complication of trauma to the tooth during its developmental stages. The possible pathogenesis which is suspected in the above case is the localised destruction of HERS which could have occurred after the invagination of HERS but before the deposition of dentin. This can be further explained on the fact that the dental age of the patient correlates with the possibility of occurrence of this pathogenesis.[14]{Table 1}

An immature tooth has an excellent capacity to recover on its own. Moreover, the patient became asymptomatic within a week after treatment with antimicrobial mouth rinse and topical antimicrobial gel. These factors were taken into consideration and it was decided to withhold any invasive treatment at that stage unless indicated to avoid disturbances in subsequent root development. It was also planned to keep the patient under regular follow up. After 3 years of follow up, the patient is asymptomatic despite the breach in root.


“Aberrant root formation” is a rare but a possible complication of trauma which can occur in an immature tooth. Such an anomalous root formation has not been reported till date. The authors suggest the inclusion of this aberrancy as a potential complication occurring subsequent to infection or traumatic injury. Nevertheless, further research is needed to analyse the exact pathogenesis of this anomaly.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.


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