503: RESULTS OF USING CONE BEAM COMPUTED TOMOGRAPHY IN PATIENTS WITH PERSISTENT IDIOPATHIC FACIAL PAIN

Topic: Clinical Science
Subtopic: Pain category (ICD-11), Chronic primary orofacial pain, Imaging (e.g. fMRI, PET, MRS)

Background and Aims: The belief that persistent idiopathic facial pain (PIFP) is psychogenic persists, yet evidence suggests it belongs to a heterogeneous group of conditions. Factors contributing to PIFP may include disproportionate responses to mild injuries, similar to complex regional pain syndrome, and unjustified dental interventions, which are considered likely etiological factors. Additionally, the diagnostic criteria for PIFP require the absence of detectable pathology via radiation diagnostics, leading to misunderstandings due to unclear guidelines on necessary methods and projections [1,2,3,4,5,6,7].
The aim was to identify radiological characteristics specific to patients with PIFP, as well as to formulate risk factors for its development.

Methods: The study of bone mineral density (BMD), topographic and anatomical features of the facial skeleton, variants of the anatomy of the branches of the trigeminal nerve using cone-beam computed tomography was carried out.
The patients were divided into groups:
Group A (n=64) – patients with PIFP [5]
Subgroup A1 (n=8) – normal BMD
Subgroup A2 (n=42) – osteopenia
Subgroup A3 (n=14) – osteoporosis
Group B (n=64) – patients with prosopalgia associated with trigeminal nerve damage (n=64)
Subgroup B1(n=32) – Classical trigeminal neuralgia
Subgroup B2 (n=32) – Other trigeminal neuropathic pain
Group C (control, n=33) – people without pain

Results: In patients with PIFP, BMD reduction per the 3D MOI CQ index was more frequent (56 (87.5%)) than in comparison groups: 42 (65.6%) had osteopenia and 14 (21.9%) had osteoporosis (P<0.05). ID, IIID, IC, and IIIC inferior alveolar nerve (IAN) branching types were exclusive to PIFP. We developed a scale indicating that the probability of PIFP increases with molar removal, a 3D MOI CQ of C2 (p=0.01) or C3 (p=0.033), a gonial angle less than 118 (p=0.000), mechanical action on the IAN (p=0.000), and asymmetry in the FAI Me index (p=0.000) [8,9].

Conclusions: The development of pain syndrome in patients with PIFP is based on the microtraumatization of the bone tissue of the facial skeleton, occurring against the background of a decrease in the threshold of an acceptable "safe" level of mechanical stress on bone structures. This decrease is due to a combination of individual risk factors. These risk factors consist of both micro- and macrostructural features of the facial skeleton, which render it less resistant to traumatic factors, particularly in the context of decreased BMD. This includes dental manipulations as well as hyperthreshold chewing loads.

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8. de Castro, J.G.K. A new cone-beam computed tomography-driven index for osteoporosis prediction / J.G.K. de Castro, B.F. Carvalho, N.S. de Melo [et al.] // Clin. Oral Investig. – 2020. – Vol. 24, N 9. – P. 3193-3202.
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Presenting Author: Zykova Oksana Mikhailovna
Submitting Author: Oxana Zykova

Senior Author: Zykova Oksana Mikhailovna

IASP 2026 Global Year theme of Neuropathic Pain: Yes

• Baliazina Elena Viktorovna: MD, professor - Rostov State Medical University