Pulp canal obliteration after traumatic injuries in permanent teeth – scientific fact or fiction?

Abstract

Pulp canal obliteration (PCO) is a frequent finding associated with pulpal revascularization after luxation injuries of young permanent teeth. The underlying mechanisms of PCO are still unclear, and no experimental scientific evidence is available, except the results of a single histopathological study. The lack of sound knowledge concerning this process gives rise to controversies, including the most suitable denomination. More than a mere semantic question, the denomination is an important issue, because it reflects the nature of this process, and directly impacts the treatment plan decision. The hypothesis that accelerated dentin deposition is related to the loss of neural control over odontoblastic secretory activity is well accepted, but demands further supportive studies. PCO is seen radiographically as a rapid narrowing of pulp canal space, whereas common clinical features are yellow crown discoloration and a lower or non-response to sensibility tests. Late development of pulp necrosis and periapical disease are rare complications after PCO, rendering prophylactic endodontic intervention useless. Indeed, yellowish or gray crown discoloration may pose a challenge to clinicians, and may demand endodontic intervention to help restore aesthetics. This literature review was conducted to discuss currently available information concerning PCO after traumatic dental injuries (TDI), and was gathered according to three topics: I) physiopathology of PCO after TDI; II) frequency and predictors of pulpal healing induced by PCO; and III) clinical findings related to PCO. Review articles, original studies and case reports were included aiming to support clinical decisions during the follow-up of teeth with PCO, and highlight future research strategies.

Clinical Perspectives of Pulp Regeneration

“…Special attention should be given to teeth immediately after trauma. Here, the lack of response to pulp sensibility tests is frequently observed during post-traumatic pulpal healing and cannot be associated with later development of pulp necrosis 35 . This diagnostic uncertainty may lead to unnecessarily invasive treatment resulting in a root canal filling.…”

“…Total or partial root canal obliteration, which is often seen in traumatized teeth, can also occur after revitalization 35 . After obliteration, teeth tend to present a negative or lower response to sensibility testing.…”

“…After obliteration, teeth tend to present a negative or lower response to sensibility testing. Another problem with such teeth is crown discoloration to a yellowish or, more seldom, gray hue 35 . The development of pulp necrosis is a late complication after pulp obliteration, but the response to pulp sensibility tests and tooth discoloration are not reliable criteria for defining pulp necrosis in this context.…”

Apicectomia e obturação retrógrada de dente com calcificação radicular interna: relato de caso

“…Além disso, a energia do trauma físico pode resultar em um alongamento do suprimento neurovascular do forame apical, assim como uma ruptura parcial ou total do suprimento. Tais condições podem levar a alterações funcionais culminando em morte pulpar, permitindo a entrada de bactérias (Andreasen & Kahler, 2015;Krastl, et al, 2016;Bastos & Côrtes, 2018).…”

Vital pulp therapy of mature permanent teeth with irreversible pulpitis from the perspective of pulp biology

“…Pulp canal obliteration has been observed following dental trauma and endodontic treatment procedures. The prevalence of pulp canal obliteration after traumatic injuries to the teeth varies widely from 3.7% to 40% . For replantation, the prevalence is 96% of avulsed immature teeth .…”