Anaesthetic efficacy of a labial infiltration method on the nasopalatine nerve

The conventional nasopalatine nerve block is commonly used to obtain anaesthesia in the anterior portion of the palate. The painful nature of this approach, however, has led investigators to seek alternative methods to obtain anaesthesia. Labial infiltration of the maxillary central incisors can be considered an effective anaesthetic approach for the anterior palate. Our study aimed to assess the anaesthetic effect of a modified labial infiltration method on the nasopalatine nerve.

A case-control clinical trial was done on 60 patients referring for extraction of maxillary incisors (mean age 44 years). The patients were divided into two groups of 30 people. For the first group, a primary conventional infiltration was given to each patient from a point between the maxillary canine and the lateral to obtain preliminary anaesthesia for the maxillary anterior labial area. The second or the control group was anaesthetised by conventional injection into incisive papilla. Two to three minutes afterwards, a labial infiltration approach was done and the amount of pain determined by OPS (objective pain score) was assessed. After five to six minutes the level of anaesthesia in the anterior palate was assessed in both groups by an explorer and recorded as pain-free, mild pain or severe pain. The sign test was used to statistically analyse the data (p <0.001).

Total, moderate and no anaesthesia were observed in 76.7%, 13.3%, and 10% of the patients receiving anesthetic injection at the labial side. For the control group, these results were 83%, 17% and 0% respectively.

This method of labial infiltration may be an effective alternative to the painful conventional palatine nerve block to obtain efficient anaesthesia of the anterior palate (p <0.001).