Accidental injection of 2% chlorhexidine gluconate instead of an anesthetic agent: A case report

Injection of sodium hypochlorite into soft tissues of the oral cavity: A literature review with clinical preventive recommendations

Injection of sodium hypochlorite (NaOCl) solution instead of local anaesthetic (LA) solution is an iatrogenic error with serious consequences including medico-legal implications. Such cases have been reported despite recommended precautionary measures. The purpose of this article is to review the literature on such cases and present clinical preventive recommendations. Electronic search was conducted in PubMed/Medline, Google Scholar, Cochrane, Scopus, Lilacs, ScienceDirect, and Crossref databases for articles reporting accidental or mistaken or inadvertent injection of NaOCl instead of LA during dental or endodontic treatment. Articles reporting NaOCl accident due to extrusion or injection of NaOCl beyond root confines were excluded. A total of 11 articles were found and reviewed. Data pertaining to the patient, injected NaOCl, cause, clinical manifestations, management, hospitalization, healing and recovery, and long-term or residual effects were extracted, compiled, and analysed for interpretation and discussion. Injection of NaOCl instead of LA into the soft tissues leads to varying clinical manifestations with unpredictable extent, outcome, and recovery period. The onus lies with the clinician to prevent it. Therefore, a clinician must take all the precautionary measures and confirm the identity of LA and NaOCl solutions before delivering them. The presented clinical recommendations assist clinicians to prevent it, including its potential medico-legal consequences. However, in case of such an unfortunate event, it is crucial to immediately identify and quickly manage it to limit the tissue damage or complications.

Accidental Injection of Chlorhexidine during Endodontic Therapy

The use of chlorhexidine gluconate (CHX) as an irrigating solution in an anesthesia cartridge is a wrong procedure commonly performed in daily clinical practice. Being an invasive procedure, it is invariably associated with complications. A 47-year-old healthy woman was injected accidentally with 2% CHX in the buccal vestibular area instead of an anesthetic solution during a root canal treatment. After the injection, the patient experienced local side effects, such as a burning sensation on the right cheek area, also a discomfort perception at the injection site and a slight inflammation with a mild extraoral redness especially on the right side cheek. The patient was prescribed with antibiotics and anti-inflammatories to reduce pain and inflammation. The patient complained of upper lip numbness by the second day of the accident. The extraoral swelling reduced gradually and the redness diminished considerably over a period of 6 days. At day 60 of follow-up, the patient recovered satisfactorily from extraoral inflammation but still presented a slight numbness of the upper lip. As a conclusion, we can claim that anesthesia cartridges with irrigant solutions should never be used to irrigate the root canals, and accidental injection of CHX should be carefully assessed by the clinician.

Mucosal Fenestration After 2% Chlorhexidine Extrusion Used in Substitution of Sodium Hypochlorite: A Case Report

This report describes a case of sodium hypochlorite (NaOCl) and chlorhexidine (CHX) extrusion through the apical foramen, causing acute pain, swelling and mucosal fenestration. A 62-year-old woman was referred for endodontic treatment in the first left maxillary premolar with a diagnosis of necrotic pulp. After the root canal irrigation with 2.5% NaOCl, the patient felt a burning sensation and pain. Discrete swelling and redness were noted in the patient’s face at the end of the session. Antibiotic and corticosteroids were prescribed. In the next appointment, 2% CHX was used, but another episode of extrusion occurred, with a sudden acute pain and intense swelling within a few minutes after the injection. After 2 weeks, the patient exhibited a left-side facial swelling extending anterior and inferior to the left zygomatic arch and superior to the body of the mandible. Oral antibiotic and anti-inflammatory drugs were administered. After 10 days, the swelling had completely diminished, but a mucosal fenestration and tooth mobility were verified. A cone beam CT was requested and showed a periapical lesion involving both buccal and palatal roots. After a prosthetic evaluation, the tooth extraction was indicated. One week after tooth removal, the mucosa was completely healed.

Hazards of Improper Dispensary: Literature Review and Report of an Accidental Chloroform Injection

Several clear, transparent solutions are used in endodontics. Inappropriate dispensing methods can lead to accidental injection or accidental irrigation. These accidents can cause permanent tissue damage including damage to the bone, periodontium, nerves, and vasculature. This article reports on the consequences of an accidental chloroform injection. Nonsurgical retreatment of tooth #8 was planned as part of a restorative treatment plan in a 69-year-old woman. The dentist accidentally injected chloroform instead of local anesthesia because chloroform was loaded into the anesthetic syringe. The patient experienced severe pain and swelling and soft tissue necrosis and suffered permanent sensory and motor nerve damage. A review of the literature was performed on accidents caused by improper dispensary, namely accidental injections and accidental irrigations. The data were extracted and summarized. Sodium hypochlorite, chlorhexidine, formalin, formocresol, 1:1000 adrenaline, benzalkonium chloride, and lighter fuel were accidentally injected as an intraoral nerve block or as infiltration injections. Bone and soft tissue necrosis, tooth loss, and sensory nerve damage (anesthesia and paresthesia) were the most common consequences reported. Such disastrous events can be prevented by appropriate labeling and separate dispensing methods for each solution. There is a need for disseminating information on toxicity and biocompatibility of materials/solutions used in endodontics. The authors recommend training dental students and endodontic residents on immediate and long-term therapeutic management of patients when an accidental injection or accidental irrigation occurs.