Objectives

Regenerative endodontics describes the ‘biologically based procedures designed to physiologically replace damaged tooth structures including dentin and root structures, as well as cells of the pulp‐dentin complex’ (American Association of Endodontics Glossary). Regenerative endodontic procedures offer an alternative treatment of the necrotic immature permanent tooth.

At the end of this case, the reader should understand the biological basis for regenerative endodontic procedures and should be able to identify cases in which this treatment would be appropriate.

Introduction

An 8‐year‐old girl presented with discolouration of the maxillary right central incisor. She had a history of trauma six months previously when she had a bicycle accident and chipped her tooth.

Medical History

Unremarkable.

Dental History

The patient had a bicycle accident during a holiday weekend six months previously. At that time, she chipped her tooth and she was taken to her paediatric dentist. She was monitored for signs of alveolar fracture and the condition of the adjacent teeth. The chip was repaired and she was feeling well. She returned for a routine dental visit and her dentist noticed a change in the colour of the tooth and took a radiograph. She was subsequently referred for endodontic specialty care.

Clinical Examination

Clinical examination revealed tenderness to palpation in the anterior buccal vestibule over the upper right central incisor (UR1). The tooth was not mobile or tender to percussion. Periodontal probing depths were within normal limits. The tooth did not respond to thermal or electric sensitivity tests and was discoloured (grey).

Diagnosis and Treatment Planning

The diagnosis was symptomatic periapical periodontitis associated with an infected necrotic pulp of an immature permanent tooth.

Treatment options discussed with the patient’s parents were:

• Regenerative endodontic treatment – If root maturation can be achieved, the root would have increased structural integrity, which may improve fracture resistance. The patient and her parents were informed of the possibility that the tooth may require root canal therapy in the future.
• Root canal therapy with apexification.
• Internal bleaching would be performed to address the discoloration following either the regenerative endodontic procedure or root canal therapy with mineral trioxide aggregate (MTA) apexification.

The patient and her parents were interested in saving the tooth and treating the infection and discolouration. Due to the benefits of continued root maturation, they decided to treat with regenerative endodontic treatment.

Treatment

The first visit involved local anaesthesia with 2% lidocaine with 1 : 100 000 epinephrine, followed by dental dam placement and access into the root canal. Minimal instrumentation of the canal was performed. The canal was copiously and slowly irrigated with 1.5% sodium hypochlorite (20 ml, five minutes) followed by irrigation with 17% ethylenediaminetetraacetic acid (EDTA; 20 ml, five minutes), with the irrigating needle measured for delivery at least 1 mm from the root end to minimise cytotoxicity to the periapical tissues. The canal was dried with paper points. A double antibiotic paste of ciprofloxacin and metronidazole was placed in the canal as an intracanal antimicrobial dressing and a Cavit™ (3M, St. Paul, MN, USA) temporary restoration was placed in the access opening (Figure 3.3.1b).