The deep sensibility of the face is still a matter of controversy, particularly in what regards the nerves responsible for its transmission. Some authors ascribe this role to the trigeminal nerve, and others to the nervus intermedius. It is also discussed which part (pontine or mesencephalic) of the trigeminal nerve carries the proprioceptive sensibility. As a contribution to the solution of the problem the authors studied, in 23 patients who underwent selective trigeminal rhizotomy, the cutaneous (touch, pain and temperature) and deep sensations (pressure and vibration senses) of the face. The quantitative and qualitative changes observed were statistically analysed. An increase in the threshold of deep sensations in the side of the face ipsilateral to trigeminal section was evidenced. The mean of the vibratory perception threshold in the facial areas ipsilateral and supplied by the sectioned radicular fibers was significantly higher than the mean relating to the contralateral side of the face. Nevertheless, the qualitative study did not show a significant correlation between vibratory hypoesthesia and surgical section of the radicular fibres, even in six patients who had a slight facial palsy as an operative sequel. A highly significant correlation was found between the changes in exteroceptive sensations (particularly touch) and the sectioned radicular fibers. The results are commented under the light of the current knowledge on the complex nature of the vibration sense. The authors reach to the conclusion that the trigeminal nerve is one of the pathways for the deep sensibility of the face, provided that one regards as responsible for this sensation the totality (indivisible by semiotic methods) of receptors located in the muscles derived from the first and second branchial arches, concerned with mastication and facial expression.