Factors influencing nerve damage during lower third molar surgery.

OBJECTIVE

To investigate relationships between pathology, eruption status, age, anaesthetic modality and nerve damage during lower third molar surgery.

DESIGN

Single centre prospective study.

SETTING

Oral surgery out-patient clinics.

SUBJECTS: 367 patients unselected for age, gender or social class, scheduled for lower third molar removal. At 1 week, any evidence of iatrogenic nerve damage was recorded. Patients with altered lingual and/or labial sensation were followed up for 6 months.

RESULTS

718 lower third molars were removed from 250 males and 117 females. 96 removals (13.4%) were associated with altered lingual, labial or buccal sensation. There were no significant associations between nerve damage and eruption status, age and pre-operative pathology. There was a highly significant difference in the incidence of nerve damage between LA removal (3%) and GA removal (18%) (chi-squared = 17.18; f = 2; P < 0.01) but no significant associations between surgical difficulty and nerve damage within each of the two groups.

CONCLUSIONS

Lingual and inferior alveolar nerve damage was five times more frequent when lower third molars were removed under general anaesthesia rather than local anaesthesia. This could not be explained in terms of surgical difficulty, pre-operative pathology, age or anatomical position.