Background & Aims

The prescription that one of the conditions for the diagnosis of persistent idiopathic facial pain (PIFP) is normal radiographic examination creates the ground for misunderstanding: there is no clear list of methods and radiological projections [1,2]. Currently there are methods of neuroimaging, such as cone beam computed tomography (CBCT), with higher resolution, that allows to see previously inaccessible structures [3,4,5].
The aim of the study was to identify radiological and laboratory characteristics specific to patients with PIFP by assessing the topographic and anatomical features of the bones of the facial skull, the location of the branches of the trigeminal nerve in the bone channels, mineral bone density (MBD) by means of CBCT, analysis of markers of bone metabolism (total and ionized calcium, inorganic phosphorus, 25(OH)VitD, alkaline phosphatase) and comparison of the data obtained with the indicators of patients with other types of prosopalgia and the control group.

Methods

The study included patients with prosopalgia that met the criteria of ICOP1: 6.2 Persistent idiopathic facial pain (PIFP), 4.1.1.1. Classical trigeminal neuralgia (CTN), 4.1.2. Other trigeminal neuropathic pain (TNP) [1], without severe somatic, neurological, psychiatric pathology. The study included 128 patients aged 24 to 75 years, 41 of them men (32%(95) 28.8-35.2)), 87 women (68% (95%CI 63.8-69.2)), the average age was 52.6±13.3 years (M±SD). In relation to BMD the patients with PIFP were divided into groups: group A included 64 patients with PIFP (subgroup A1 – 8 (12,5%) with normal BMD), A2 – 42 (65,6%) with osteopenia, A3 – 14 (21,9%) with osteoporosis). Group B consisted of 32 patients with CTN, group C – 32 patients with trigeminal neuropathy (TNP). Control group D consisted of 33 participants without pain syndrome. All patients underwent CBCT, the study of markers of bone metabolism (total and ionized calcium, phosphorus, alkaline phosphatase, 25-OH vitamin D).

Results

Significant differences of descent type (straight projection, cetenaty-like configuration or progressive) (?2=50.5; p<0.001), variants of branching of the inferior alveolar nerve (IAN) (single unbranched nerve, a series of separate branches, thin molar plexus, proximal and distal nerve plexuses (?2=282.5; p<0.001)), doubling and tripling of the IAN (?2=1196.9; p<0.001), facial skeletal abnormalities in groups were revealed (? 2=124018.9; p<0.001) [6,7]. The most frequent variants of IAN are: group A1 – IA (37,5%) and IIA (62,5%), group A2 – IIID (28,6%), group A3 – ID (21,5%) and IIID (43,1%), group B – IIB (78,1%), group C – IIIA (43,8%) and IIIB (50%), group D – IB (21,2%) and IIIB (39,4%) (?2=271.6; p<0.001). Mechanical impacton on IAN was detected in 59,5% with osteopenia, 19% with osteoporosis and 18,8% with TNP. Relationships between 3D MOI PR and CS and the level of alkaline phosphatase (r1=-0.58; r2=-0.75; p<0.05) and phosphorus were detected (r1=0.57; r2=0.55; p<0.05) [8].

Conclusions

Among the variety of pathology, systemic osteoporosis is taking one of the leading positions. It affects all bones, including the facial skeleton, but it has not attracted attention due to the minimal likelihood of pathological fractures. The facial skeleton is a unique area for the early detection of osteoporosis [9]. Predominant number of patients with PIFP have reduced BMD. Certain patterns of the facial skeleton in patients with PIFP were revealed and made it possible to identify a risk group for developing PIFP: a patient with altered levels of phosphorus and alkaline phosphatase, signs of decreased BMD, type IAN IIID, unilateral or bilateral mechanical effects on IAN. Information about the the topographic and anatomical features of the facial skeleton can be used as an auxiliary method for early diagnosis and prevention of the development of PIFP and can especially be useful for planning dental procedures taking into account all anatomical features and risk factors.

References

1.International Classification of Orofacial Pain, 1st edition (ICOP). Cephalalgia. 2020 Feb;40(2):129-221. doi: 10.1177/0333102419893823. PMID: 32103673.
2.Headache Classification Committee of the International Headache Society (IHS) The International Classification of Headache Disorders, 3rd edition. Cephalalgia. 2018 Jan;38(1):1-211. doi: 10.1177/0333102417738202. PMID: 29368949.
3.Forssell H, Jääskeläinen S, List T, Svensson P, Baad-Hansen L. An update on pathophysiological mechanisms related to idiopathic oro-facial pain conditions with implications for management. J Oral Rehabil. 2015 Apr;42(4):300-22. doi: 10.1111/joor.12256. Epub 2014 Dec 8. PMID: 25483941.
4.Balyazina EV, Evusyak OM, Kharitonova KP. [Role of vitamin D deficiency in chronic pain syndrome in patients with persistent idiopathic facial pain]. Rossijskij zhurnal boli. [Russian journal of pain]. 2020;18(2):9–13. (In Russ.). doi.org:10.17116/pain2020180219.
5.Whyte, A., & Matias, M. A. T. J. (2020). Imaging Of Orofacial Pain. Journal of Oral Pathology & Medicine. doi:10.1111/jop.13063
6.Ozturk, A., Potluri, A., & Vieira, A. R. (2012). Position and course of the mandibular canal in skulls. Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology, 113(4), 453–458. doi:10.1016/j.tripleo.2011.03.038
7.Kieser J, Kieser D, Hauman T. The course and distribution of the inferior alveolar nerve in the edentulous mandible. J Craniofac Surg. 2005 Jan;16(1):6-9. [Medline: 15699637]
8.De Castro, J. G. K., Carvalho, B. F., de Melo, N. S., de Souza Figueiredo, P. T., Moreira-Mesquita, C. R., de Faria Vasconcelos, K., … Leite, A. F. (2020). A new cone-beam computed tomography–driven index for osteoporosis prediction. Clinical Oral Investigations. doi:10.1007/s00784-019-03193-4
9.Kyrgidis A, Tzellos TG, Toulis K, Antoniades K. The facial skeleton in patients with osteoporosis: a field for disease signs and treatment complications. J Osteoporos. 2011 Feb 16;2011:147689. doi: 10.4061/2011/147689. PMID: 21403823; PMCID: PMC3042625.
10.Benoliel, R., & Gaul, C. (2017). Persistent idiopathic facial pain. Cephalalgia, 37(7), 680–691. doi:10.1177/0333102417706349
11.Schweiger, V.; Nocini, R.; De Santis, D.; Procacci, P.; Zanette, G.; Secchettin, E.; Del Balzo, G.; Fior, A.; Martini, A.; Nizzero, M.; et al. Persistent Idiopathic Facial Pain (PIFP) in Patients Referred to a Multidisciplinary Centre in Italy: A Retrospective Observational Study. J. Clin. Med. 2022, 11, 3821. https:// doi.org/10.3390/jcm11133821
12.Gerwin R. Chronic Facial Pain: Trigeminal Neuralgia, Persistent Idiopathic Facial Pain, and Myofascial Pain Syndrome-An Evidence-Based Narrative Review and Etiological Hypothesis. Int J Environ Res Public Health. 2020 Sep 25;17(19):7012. doi: 10.3390/ijerph17197012. PMID: 32992770; PMCID: PMC7579138.

Presenting Author

Zykova Oksana Mikhailovna

Poster Authors

Oxana Zykova

PhD student

Lead Author

Bogdan Akhmedov

Lead Author

Anastasia Afanasieva

Lead Author

Topics

  • Specific Pain Conditions/Pain in Specific Populations: Orofacial Pain