12-Year Follow-Up of Regenerative Endodontic Treatment of Immature Permanent Upper Incisors with Acute Abscess

Abstract

This case report discusses the endodontic treatment of a 7-year-old girl who suffered trauma (intrusion) to the immature upper central incisors secondary to a fall from a bicycle. Thirty days after the accident the patient was brought by her mother for clinical and radiographic assessment with a chief complaint of swelling and tenderness to percussion and palpation. Acute apical abscess associated with immature teeth were diagnosed. A decision was made to perform regenerative endodontic treatment. Access cavities were made and the root canals were disinfected by irrigation with 2.5% sodium hypochlorite. Final irrigation was performed with 17% EDTA. Due to pain and presence of secretions, 2% chlorhexidine gel was applied as an intracanal medicament. Seven days later, at the second visit, the root canals were once again disinfected and the canals of the right and left permanent upper central incisors were filled with double antibiotic paste (metronidazole/ciprofloxacin) and calcium hydroxide paste, respectively. Zinc oxide was mixed in both pastes. At the third visit, after 21 more days, the pastes were removed and the periapical areas were stimulated with a #80 K-file to encourage clot formation within the pulp cavities. A mineral trioxide aggregate (MTA) paste cervical plug was placed and the teeth were restored with glass ionomer cement. Radiographs and CBCT scans demonstrated complete root formations. The patient has been followed for 12 years, with evidence of clinical success throughout.

Regenerative Endodontics as the Future Treatment of Immature Permanent Teeth

“…In 2020, Maniglia-Ferreira et al [104] described a case of REP treatment of two central incisors with a 12-year follow-up. It consisted of 2.5% NaOCl, 17% EDTA, and 2% CHX gel used for disinfection (for one week), and then DAP was applied to one tooth and Ca(OH) 2 to the other (for three weeks).…”

Expert consensus on regenerative endodontic procedures

“…Though most case reports and clinical studies have proved increased root length, thickened root wall and decreased size of apical foramen in immature teeth after REPs, 13 , 20 , 48 , 53 , 56 – 59 histological evaluation of the teeth treated with REPs have shown that the newly formed tissue were ectopic bone, cementum, and periodontal ligament instead of dental pulp or pulp-like tissue. 60 – 63 Animal studies have also confirmed the above results.…”

“…In terms of regain of a positive response to pulp sensibility test after REPs, it was present in 50%~60% of published cases. However, researchers 33 , 48 suggested that positive response to pulp sensibility test in immature permanent teeth with pulp necrosis after REPs could not be taken as a proof of pulp regeneration, provided that by now no reorganized vital pulp tissue has been detected in the treated teeth, but just vital tissues containing cementum-like, bone-like tissue and nerve fibers. The vital soft tissues might be able to respond to pulp test to some degree probably because they are vascularized and innervated.…”

“…Blood clot has been induced as a scaffold in most of the REPs cases, 43,[46][47][48] which is a relatively straightforward and simple approach. It allows integrators on cell surfaces to adhere to fibrous components and selectively adsorb cells, supplying growth factors to promote tissue regeneration.…”

“…An in vivo study showed that decellularized dental pulp of swine implanted into pulpectomized teeth in dogs could induce the formation of a vascularized pulp-like tissue with expression of odontoblastic markers. 55 Histological evaluation of REPs Though most case reports and clinical studies have proved increased root length, thickened root wall and decreased size of apical foramen in immature teeth after REPs, 13,20,48,53,[56][57][58][59] histological evaluation of the teeth treated with REPs have shown that the newly formed tissue were ectopic bone, cementum, and periodontal ligament instead of dental pulp or pulp-like tissue. [60][61][62][63] Animal studies have also confirmed the above results.…”