Transmission mechanisms in dental pain

Clinical neurosensory testing: practical applications

A relatively large percentage of the practicing oral and maxillofacial surgeon's patients experience some degree of neurosensory impairment as a normal concomitant of major surgery. Additionally, some patients develop neurosensory disturbances unexpectedly following routine surgical procedures. This report describes a practical approach to evaluating these individuals, which is essential in making intelligent decisions regarding the objective nature of the nerve injury, potential for recovery, and/or possible need for secondary microneurosurgical intervention.

Assessment of recovery from injury to inferior alveolar and mental nerves

Thirty-four patients had surgery near but not transecting either the inferior alveolar nerve or mental nerve. Thermal tests revealed that between 62% and 81% of the nerves that were evaluated had sensory deficits. Sixty-seven percent of patients had abnormal intraoral and extraoral responses to fine tactile testing. The least discriminative test was two-point contact. A smaller percentage (14% to 23%) were hyperpathic to heat stimuli, and a few (5% to 15%) had completely normal thermal and tactile sensation. A high percentage (43% to 71%) of patients elected to have corrective nerve surgery.

The ontogeny of substance P--containing nerve fibres in the developing mouse dentition

The putative neurotransmitter, substance P, was localised in the developing teeth and periodontium of mice by indirect immunofluorescence. Substance P-containing fibres were visible in the incisor dental follicle eighteen days post-conception and entered the pulp two days after birth. The first molar pulp was innervated four days after birth and the second molar six days after birth. Innervation of the teeth by substance P fibres was delayed compared with the mucous and cutaneous innervation of adjacent areas and correlated with the stage of development of the teeth rather than the chronological age of the animal. The innervation of developing dental structures by substance P probably represents the establishment of a sensory supply prior to function of the tooth.