Efficacy and feasibility of frontozygomatic angle approach for extra oral maxillary nerve block in oral surgery: a descriptive clinical trial.

BACKGROUND: Pain control is an integral part of minor oral surgery and maxillary/mandibular nerve blocks have proved promising in achieving the same. Although intra oral techniques of maxillary nerve block are common and are widely used, there are certain inherent disadvantages and potential complications. Less commonly described in the literature, the extra oral techniques have a wide spectrum of indications as well as can be more advantageous than the intra oral approach. This prospective clinical trial is an attempt to evaluate the feasibility and the efficacy of the extra oral frontozygomatic approach to the foramen rotundum to block the maxillary nerve.

MATERIALS AND METHODS: Sample size was 100 patients and the inclusion criteria were patients of ASA I or II category who needed extraction of a minimum of 4 maxillary teeth in the same quadrant in a single sitting while exclusion criteria were patients with a history of allergy to local anesthesia, medically compromised patients in whom dental extraction was contraindicated. Mean age was 71.9 years and 56 patients were males while 44 were females. Only a single quadrant (first or second) was chosen as the operative site in each patient and local anaesthesia was secured using a 21 gauge 89 mm long spinal needle with frontozygomatic angle approach and the parameters used were pain experienced during the injection, onset of subjective symptoms, time required for the peak effect (objective symptoms), pain during extraction and the duration of anesthesia. All the parameters were expressed as mean values with standard deviations.

RESULTS: A successful anesthesia was secured in first attempt in 98 patients while in 2 patients, the procedure had to be repeated owing to the difficulty in reaching the target site. A majority of the patients i.e., 71 % scored 0-2 (no pain) on visual analogue scale (VAS) while only 2 patients experienced a moderate degree of pain. Subjective symptoms were reported in 27.24 s (mean value) and 12.93 s (mean value) in the palate and the infraorbital fossa respectively. Peak effect of anesthesia was noted in 66.7, 37.38 and 31.71 s (all values expressed as mean) in palate, infraorbital fossa and posterior superior alveolar areas respectively.

CONCLUSION: Although with only dental extraction as the procedure of choice, the present study has favoured the frontozygomatic angle approach for the maxillary nerve block as simple, safe, efficacious and associated with minimum and clinically mild complications.