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J Orofino

Publications and source records attributed to J Orofino.

5 recordsLinked to original sources
PubMed1995

Periodontal and gastric convergences within the hypothalamic ventromedial nucleus area--single unit study on anesthetized rats.

Unitary activities were recorded in the ventromedial nucleus of the hypothalamus (VHM) of anesthetized rats. Cells responding to periodontal stimulation (100-200 g disto-mesial traction applied to an upper incisive) were selected. The effects of gastric stimulation (2-5 ml distension) were then investigated. Out of the 40 cells activated (22 cells) or inhibited (18 cells) by periodontal stimulation, only seventeen were influenced by gastric stimulation. Eight of them responded in the same way and nine in the opposite way. Unlike the periodontal stimulation, which elicited specific spatio-temporal patterns, the gastric stimulation had only weak effects. These data nevertheless demonstrate that periodontal-gastric convergences exist in the VHM nucleus, which is consistent with the role previously ascribed to this area in alimentary behaviour.

Afferent Pathways↗
PubMed1989

[The role of intraoral mucosal receptors in the completely edentulous in the discrimination of the layers].

Studies on proprioceptive sensitivity in edentulous subjects let appear prevalent mucosal receptors compared to muscular or articular receptors. Neurophysiological mechanism seem identical in edentulous patients and statistical studies allowed us to highlight the functional characteristics of receptors in the intraoral mucosa; they replace the missing desmodontal receptors. The perception accuracy of extremely thin layers permits the practitioner to perfect his occlusal equilibration as well as to control his patient's occlusal vertical dimension with a new method of reference. The use of patient's sensitive information through their lemniscal systems should lead to a better integration of our dentures and avoid a physiopathology such as dysfunction of the temporomandibular joint.

Adult↗
PubMedDate not supplied

Electrophysiologic evidence showing the existence of sensory receptors within the alveolar bone in anesthetized cats.

Single-nerve activities were recorded in the gasserian ganglia of anesthetized cats by glass extracellular micro-electrodes to determine whether sensory endings exist within the alveolar bone. Trigeminal cells responded to mechanical and/or thermal stimulation applied to the maxillary bone. Some were activated by specific kinds of fairly precise mechanical stimuli (moderate forces applied in a preferential direction); others exhibited a coarse mechanical sensitivity. In addition, electrical stimulation was applied to the maxillary bone to determine the conduction velocities of the relevant fibers. These mainly ranged between 1 and 6 m/s, which indicates that the fibers belonged to the small-diameter category (thinnest myelinated and unmyelinated fibers). Similar results were obtained from animals with osseointegrated implants. It was concluded that the alveolar bone is endowed with sensory endings capable of detecting mechanical and thermal changes, and that these receptors may provide compensatory sensitivity in edentulous subjects whose main (periodontal) sensitivity has been eliminated.

Action Potentials↗