Biomaterial Database

Activation of intradental nerves in the dog to some stimuli applied to the dentine. 1982

M V Närhi, and T J Hirvonen, and M O Hakumäki

Both scraping of superficial dentine and air blasts induced bursts of action potentials in 19 out of 22 units immediately. In 5 out of 16 units 4.9 mol/l CaCl2-solution was also effective. Dry absorbent cotton activated 5 out of 16 units with a 10-20 s latency. All 18 units tested responded to mechanical irritation of the pulp. Acid etching of dentine made the units more sensitive. Resin impregnation abolished the responses. Drilling of dentine with a turbine bur induced responses of the same type as air blasts. Three units responded to heat and 2 also to cold. Hypertonic NaCl-solution was only effective when applied either to the pulp (in 9 out of 12 units) or to the inner dentine (in 5 out of 17 units). It is concluded that intradental nerve fibres sensitive to several different stimuli exist in the dog. Many of the stimuli used induce fluid flow in dentinal tubules in vitro. Nerve activation might have been due to the same mechanism with all stimuli used, possibly to mechanical distortion of the peripheral pulp tissue as a result of the fluid flow. The findings support the hydrodynamic hypothesis of dentine sensitivity.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009412	Nerve Fibers	Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.	Cerebellar Mossy Fibers,Mossy Fibers, Cerebellar,Cerebellar Mossy Fiber,Mossy Fiber, Cerebellar,Nerve Fiber
D010812	Physical Stimulation	Act of eliciting a response from a person or organism through physical contact.	Stimulation, Physical,Physical Stimulations,Stimulations, Physical
D002122	Calcium Chloride	A salt used to replenish calcium levels, as an acid-producing diuretic, and as an antidote for magnesium poisoning.	Calcium Chloride Dihydrate,Calcium Chloride, Anhydrous
D003782	Dental Pulp	A richly vascularized and innervated connective tissue of mesodermal origin, contained in the central cavity of a tooth and delimited by the dentin, and having formative, nutritive, sensory, and protective functions. (Jablonski, Dictionary of Dentistry, 1992)	Dental Pulps,Pulp, Dental,Pulps, Dental
D003804	Dentin	The hard portion of the tooth surrounding the pulp, covered by enamel on the crown and cementum on the root, which is harder and denser than bone but softer than enamel, and is thus readily abraded when left unprotected. (From Jablonski, Dictionary of Dentistry, 1992)	Dentine,Dentines,Dentins
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D005260	Female		Females
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia