This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Singh, B. Search for Related Content PubMed PubMed Citation Articles by Singh, B.

---

LETTER TO THE EDITOR

Mandibular Nerve Block for the Removal of Dentures During Trismus Caused by Tetanus

Department of Anaesthesiology & Intensive Care; G B Pant Hospital (University of Delhi); New Delhi, India; dr_baljit{at}yahoo.com

To the Editor:

I compliment Meaudre et al. (1) for the innovative use of bilateral mandibular nerve blocks for removal of dentures during trismus caused by tetanus. It surprises me that even after bilateral blocks with 5 mL 2% mepivacaine, it took 20 min to open the mouth 25 mm. Though the authors mention the use of an extraoral lateral approach, the crucial details of the technique and how was it ascertained that the needle had reached behind the posterior border of the lateral pterygoid plate were not mentioned. For an effective block it is absolutely essential that the distance to reach the lateral pterygoid plate be noted before redirecting the needle posteriorly. Paresthesias in the distribution of mandibular nerve are often obtained, as the nerve is situated just behind the lateral pterygoid plate.

However, injection is not safe until the needle has reached sufficient depth to reach the lateral pterygoid plate. The reason is that the needle passes through the plexus of veins around the pterygoid muscles to reach the nerve. This plexus communicates with the cavernous venous sinus. Direct injection into the plexus may lead to cavernous venous sinus thrombosis, a potentially serious complication.

Most of the complications quoted by the author are with the intraoral approach typically used for dental extractions and do not apply to the lateral extraoral approach. Ophthalmic complications are a possibility with the lateral extraoral approach during maxillary nerve block. Bilateral mandibular block may result in "drop jaw" as the two important muscles closing the mouth, the masseter and the temporalis, are paralyzed. Furthermore, the tongue is anesthetized, potentially leading to fluid collecting in the oral cavity and aspiration. Therefore, patients should be nil per os after bilateral mandibular blocks until the effect of local anesthetic wears off. If the needle is inserted too far, it may go through the superior constrictor of the pharynx and reach the pharynx. This has the potential of bringing infection into the tissues in the infratemporal fossa as the needle is pulled out.

REFERENCE

1. Meaudre E, Pernod G, Gaillard PE, et al. Mandibular nerve blocks for removal of dentures during trismus caused by tetanus. Anesth Analg 2005;101:282–3.[Abstract/Free Full Text]

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Singh, B. Search for Related Content PubMed PubMed Citation Articles by Singh, B.