Developing new biological treatments to maintain children’s natural dentition after trauma: A translational approach
Dental trauma injuries during childhood and adolescence can have an adverse impact on oral health throughout life. Population-based studies estimate that the worldwide prevalence of dental trauma in permanent young teeth is between 16-40% [1] and the incidence rate in Sweden has an upward trend [2]. When trauma injuries the teeth, dental and neurovascular supply can be disrupted, and microorganism may invade the pulp tissue, initiating and infection. About 27 % of permanent teeth with traumatic injuries can develop pulp necrosis [3]. If immature teeth lose their vitality, the root formation stops and these teeth have consequently questionable long-term survival.
Dental management of necrotic teeth with aberrant root formation represents a challenging clinical situation. The classical approach for treating these teeth includes apexification, which consist of either a long-term application of calcium hydroxide (CH) to stimulate formation of an apical barrier [4] or application of Mineral Trioxide Aggregate (MTA) as an artificial apical barrier. These procedures, however, has the downside of increase susceptibility to cervical fractures [5], involves multiple appointments with a long treatment time [6] and do not achieve the goal of continued root development or restoration of pulp tissue functionality [7]. Thus, it may imply high costs for the patient and the society.
Alternative tooth replacement treatment such as dental implants are contraindicated because the still growing craniofacial skeleton in young individuals.
In recent years, much effort has been made to find alternative treatments. A biological based approach referred as regenerative endodontic treatment (RET) has emerged as a biological procedure for necrotic pulps with aberrant root development. This treatment aims to regenerate pulp-like tissue within the root canal space after inducing an influx of stem cells from the apical papilla that results in reestablishment of pulp protective functions (Figure 2) [8]. In fact, by restoring pulpal functions, the root can continue its development. This treatment implies the possibility to help patients to maintain their natural dentition with otherwise uncertain prognosis.
Although promising, the scientific evidence for the overall efficacy of RET is scarce [9]. Short-term longitudinal studies have so far evidenced the resolution of sign and symptoms of pathology and demonstrated continuing root development in length and thickness after regeneration procedures [10; 11]. However, failed cases related to lack of bleeding and persistent infections have been reported, indicating that new techniques are needed to improve the predictability of RET [9].
The main goal of the present project is to gain knowledge about the treatment of immature necrotic teeth in young individuals due to dental trauma.
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