Effects of a liquid diet on the response properties of temporomandibular joint nociceptive neurons in the trigeminal subnucleus caudalis of growing rats. (10th April 2013)

• Record Type: Journal Article
• Authors: Hiranuma, M.; Kokai, S.; Fujita, K.; Ishida, T.; Shibata, M.; Naito, S.; Yabushita, T.; Ono, T.
• Is Part Of: Orthodontics and craniofacial research. Volume 16:Number 4(2013:Nov.)
• Page Start: 214
• Page End: 222
• Publication Date: 2013-04-10
• Subjects: Skull -- Growth -- Periodicals; Facial bones -- Growth -- Periodicals; Orthodontics -- Periodicals; Orthodontics, Corrective -- Periodicals; Orthodontic appliances -- Periodicals; 617.51
• DOI: 10.1111/ocr.12023
• Languages: English
• ISSNs: 1601-6335

Abstract

<abstract abstract-type="main" id="ocr12023-abs-0001"> <title>Structured Abstract</title> <sec id="ocr12023-sec-0001" sec-type="section"> <title>Objective</title> <p>To investigate whether low mechanical loading on the temporomandibular joint (TMJ) when ingesting a liquid diet affects the response properties of neurons in the trigeminal spinal tract subnucleus caudalis (Sp5C) in growing rats.</p> </sec> <sec id="ocr12023-sec-0002" sec-type="section"> <title>Materials and Methods</title> <p>Shortly after weaning, 2‐week‐old male rats were fed chow pellets (control) or a liquid diet (experimental). Firing activities of single sensory units were recorded from the Sp5C at 4, 5, 7, and 9 weeks. Neurons were functionally classified by their responsiveness to TMJ stimuli. The responses of Class II and III neurons to TMJ stimuli were investigated.</p> </sec> <sec id="ocr12023-sec-0003" sec-type="section"> <title>Results</title> <p>In both neuron classes, the firing threshold in the experimental group was significantly lower than in the control group at all time points, but remained static in the control group throughout the experimental period, whereas it peaked in the experimental group at 4 weeks, decreased at 5 weeks, and remained stable thereafter until 9 weeks. Similarly, the initial firing frequency was significantly higher in the experimental group than in the control group, but remained static in the control group throughout the experimental period, whereas in the experimental group, it was at its lowest at 4 weeks, increased at 5 weeks, and stayed stable thereafter until 9 weeks.</p> </sec> <sec id="ocr12023-sec-0004" sec-type="section"> <title>Conclusion</title> <p>Differences in TMJ loading arising from variable diet consistency during growth may affect the functional characteristics of Sp5C neurons.</p> </sec> </abstract>