The treatment objective for children with avulsed anterior teeth should concentrate on preserving the alveolar bone volume and contour. Posttraumatic external inflammatory root resorption (EIRR) is also a high-risk complication often observed in children. Regenerative endodontic procedure (REP) has been considered a successful treatment to arrest EIRR, especially in posttraumatic cases. This case report presents clinical outcomes of REP in two teeth of an 8-year-old systemically healthy patient with a history of severe dentoalveolar traumatic injury, one with a history of avulsion, and the other with an EIRR. The treatment consisted of REP on both teeth #8 and #9. The results showed some evidence of maturation in the apical third of tooth #9 and resolution of signs and symptoms on tooth #8.

Enterococcus faecalis is the dominant microorganism in chronic apical periodontitis. It is more resistant to local antiseptic agents than other endodontic microorganisms. Currently, mineral trioxide aggregate (MTA) is considered as an ideal material in many endodontic procedures. Some studies have shown that MTA has good antibacterial activity against E. faecalis. However, some studies have investigated the effect of incorporating some materials into MTA on its antibacterial activity against E. faecalis. No study has evaluated the effect of incorporating fluorohydroxyapatite nanoparticles (nano-FHA) on the antimicrobial activity of MTA. Therefore, the present study evaluated the antimicrobial effect of MTA mixed with nano-FHA on E. faecalis in vitro. The study was carried out on 18 samples in three groups: pure MTA, MTA mixed with 10 wt% of nano-FHA, and MTA mixed with 15 wt% of nan-FHA. The effect of nano-FHA on the antibacterial activity of MTA on E. faecalis was evaluated by evaluating the growth inhibition zone around each sample. The antimicrobial effect of samples on inhibiting E. faecalis biofilm formation and inhibiting microbial growth of E. faecalis in the planktonic phase was evaluated by disk agar diffusion (DAD), biofilm inhibition assay (BIA), and direct contact assay (DCA) tests, respectively. All the above tests were analyzed after 24 and 72 hours. Factorial designs were used for statistical analyses. Tukey tests were used for two-by-two comparisons. All the statistical analyses were carried out with SPSS 26. DAD results showed no formation of the growth inhibition zone in all the samples after 24 and 72 hours. The microbial colony counts in the BIA and DCA tests in the groups modified with FHA nanoparticles were significantly lower than the pure MTA group ( P < 0.05 ). The microbial colony counts increased in all the groups over time ( P < 0.05 ). Incorporating nano-FHA into MTA improved the antimicrobial activity of MTA against E. faecalis compared to pure MTA. The highest antimicrobial activity was achieved after incorporating 15 wt% of nano-FHA into MTA at the 72-hour interval.

Regenerative endodontic treatment (RET) is a valuable treatment for necrotic immature teeth with many advantages such as increasing root length and thickness of root wall. The success of RETs is based on healthy stem cells, suitable scaffolds, and growth factors and takes place when bacterial contamination is well controlled. The aim of this article is to address controversy in a case with multiple success criteria. This paper reports a 9-year-old boy with a complicated crown fracture of the maxillary left central incisor about three years prior to referral with a diagnosis of intrusive luxation with spontaneous reeruption. The tooth had an underdeveloped root and a well-defined periapical radiolucent lesion around the root apex. RET was considered according to the stage of root development. Upon the three-week recall session, the clinical examination indicated that the patient was asymptomatic in the affected site. However, the patient returned two weeks later with a sinus tract pertaining to the apex of tooth #9. Therefore, debridement of the root canal space was repeated and the RET redone. On the second trial, the patient was symptom-free, but no more evidence of root maturation was observed on 18-month follow-up. The tooth was asymptomatic (without swelling, drainage, and pain) during this time, and esthetics was provided for the patient.

Regenerative endodontic management is a feasible treatment for immature teeth with periapical radiolucency and necrotic pulp that simplifies continued root creation. Among the most prevalent health problems in an immature root is dental pulp necrosis, which is caused by caries, improper endodontic treatments, and trauma. Necrosis of the dental pulp can affect long-term tooth survival and preservation and serve as a source of bacteria infecting the periapical tissue and the maxillofacial space. Here, we report on the application of advanced platelet-rich fibrin plus (A-PRF+) therapy, as a regenerative endodontic treatment (RET), in a 12-year-old with necrotic pulp and asymptomatic apical periodontitis. Over a 24-month follow-up post-treatment, we observed resolving of symptoms and a complete root formation with considerable periapical healing.