Comparative Evaluation of Somatosensory Mechanisms Involved in Genesis of Somatic, Visceral and Neuropathic Orofacial Pain.

• Grant number: 13/15496-1
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): December 01, 2013
• Effective date (End): March 31, 2016
• Field of knowledge: Health Sciences - Dentistry
• Principal researcher: Paulo César Rodrigues Conti
• Grantee: André Luís Porporatti
• Home Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil

Abstract

Orofacial pain can be divided, mainly, into somatic, visceral and neuropathic pain. Somatic pain is related to a obvious noxious stimulus, a more accurate and defined pain and generally related to peripheral trauma, which occours, for example, in implants surgery. Visceral pain originates within the internal organs and cavities and are activated by inflammation, as for instance, an Irreversible Acute Pulpitis (IAP). Neuropathic pain occurs in the absence of any obvious noxious stimulus and are possibly associated with a nerve fiber lesion with abnormal somatosensitivity, which happens in Atypical Odontalgia (AO). The impact of these conditions on individual's life may have a significant participation of catastrophizing behavior. The aims of this study are: 1) To evaluate peripheral and central mechanisms of neural conduction in healthy patients requiring treatment with dental implants, and IAP subjects before, 01 day after, 1 month and 3 months after the implant surgery (somatic stimulus) and pulpectomy, respectively, 2) To evaluate peripheral and central mechanisms of neural conduction in patients with AO; and 3) To evaluate the influence of catastrophizing on pain perception. A total of 20 healthy subjects requiring treatment with dental implants (Group 01 - Somatic), 20 subjects with IAP (Group 02 - Visceral) and 20 subjects with AO (group 03 - Neuropathic) will be included. Research subjects will be evaluated through quantitative sensory testing (QST) and nerve conduction test (CPT), as well as pain reports and catastrophizing questionnaires. QST encompassed Mechanical Detection Threshold (MDT), Pain Detection Threshold (PDT), Dynamical Mechanical Allodynia with a cotton swab (DMA1) and with a toothbrush (DMA2), Wind-up Ratio (WUR) and Controlled Pain Modulation (CPM). CPT is an electrical Evaluating performed with the aid of the Neurometer CPT (Neurometer ® Painless electrodiagnostic Nerve Sensory Testing Equipment) that measures the neural conduction threshold, or the minimum electrical stimulus to a nerve, needed to induce a response. CPT and QST will be performed in dentoalveolar mucosa, near the area involved in pain or implant insertion (somatic pain). Statistical analysis will be done using ANOVA for repeated measures with the purpose of identifying significant differences within and between groups, considering a significance level of 5%.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

PORPORATTI, ANDRE LUIS; BONJARDIM, LEONARDO RIGOLDI; STUGINSKI-BARBOSA, JULIANA; BONFANTE, ESTEVAM AUGUSTO; COSTA, YURI MARTINS; RODRIGUES CONTI, PAULO CESAR. Pain from Dental Implant Placement, Inflammatory Pulpitis Pain, and Neuropathic Pain Present Different Somatosensory Profiles. JOURNAL OF ORAL & FACIAL PAIN AND HEADACHE, v. 31, n. 1, p. 19-29, WIN 2017. Web of Science Citations: 6.

PORPORATTI, ANDRE LUIS; COSTA, YURI MARTINS; STUGINSKI-BARBOSA, JULIANA; BONJARDIM, LEONARDO RIGOLDI; HUNGARO DUARTE, MARCO ANTONIO; RODRIGUES CONTI, PAULO CESAR. Diagnostic Accuracy of Quantitative Sensory Testing to Discriminate Inflammatory Toothache and Intraoral Neuropathic Pain. JOURNAL OF ENDODONTICS, v. 41, n. 10, p. 1606-1613, OCT 2015. Web of Science Citations: 7.