Dentist № 4 (43) – 2021, pp. 39-46                                                                                                SCIENTIFIC PUBLICATION


The role of iodine-containing thyroid hormones in postfracture restoration of function and regeneration of the area of traumatic injury of the lower jaw under stress


I.V. Gorodetskayaa, T.N. Markevichb

aMD, PhD, DMSci, Professor, Vitebsk State Medical University”, Vitebsk, Belarus
bVitebsk State Medical University”, Vitebsk, Belarus

https://doi.org/10.32993/dentist.2021.4(43).2

ABSTRACT
The aim of the study is to establish the significance of hypothyroidism in stress-induced postfractural changes of rats mandibular function and structure.
Objects and methods. The experiments were performed on 90 outbred sexually mature white male rats weighing 180-230 g. Stress was executed by “free swimming in the cage” for 30 minutes during 14 days. The fracture of the lower jaw was modeled by using a spherical burr, with which a hole with a diameter of about 2.0 mm was made in the area of projection of the roots of the first left molar in the body of the bone. Hypothyroidism was induced by intragastric introduction of mercazolil (25 mg/kg for 20 days) in 1% starch paste. The function of the lower jaw was assessed by the speed of chewing food of various degrees of hardness and chewing efficiency; its microstructure was investigated on preparations stained with hematoxylin-eosin.
Results and discussion. Stress provokes a greater drop in chewing function in the case of a fracture of the lower jaw due to inhibition of the process of restoration of the damaged area – it decreases the number of islets of cartilaginous and immature bone tissue on the background of the increase of the number of dense irregular connective tissue, collagen fibers and of the area of Haversian canals. These facts indicate retardation of the phases of reparative response. Experimental hypothyroidism negatively affects on the trophics of the mandibular tissue per se and slows down the healing of a bone defect after fracture – both and isolated and combined with stress, resulting in worsening of the chewing function under these conditions.
Conclusion. The participation of iodine-containing thyroid hormones in post-fracture osteoregeneration and restoration of the function of the lower jaw under the influence stress has been proved.

Keywords: iodine-containing thyroid hormones, fracture, stress

References 

  1. Averyanov S.V., Galieva E.I., Ryabykh L.A., Mingazeva A.Z. Travmy chelyustno-licevoj oblasti [Injuries of the maxillofacial area]. Ufa: FSBEI HE BSMU of the Ministry of Health of the Russian Federation, 2019. 26 р.
  2. Efimov Y.V., Stomatov D.V., Efimova E.Y. Dolgova I.V., Stomatov A.V. Lechenie bol’nyh s odnostoronnim kosym perelomom nizhnej chelyusti [Treatment of patients with unilateral oblique fracture of mandible]. Med. vestn. Sev. Kav. Med. – News of North Caucasus. 2019, vol. 14, no. 1.1, рр. 94–98.
  3. Urbanovich V.I., Vylegzhanin T.A. Vliyanie stressa na nejrotkanevye izmeneniya v desne [Influence of stress on neuro-tissue relations in the gingiva]. Stomatolog. Minsk. – Stomatologist. Minsk. 2018, no. 2, рр. 62–68.
  4. Lombardo G., Corrocher G., Migliorini L., Romoli L., Fiorino A. Stress kak faktor riska razvitiya periodontita (chast’ 1) [Stress as a risk factor of development of periodontitis (part 1)]. Stomatolog. Minsk. – Stomatologist. Minsk. 2012, no. 2 (5), рр. 14–23.
  5. Tazhibaeva D.S., Kabdualieva N.B., Bajbakova M.K., Beglarova G.E., Zaripova L.N. Vliyanie hronicheskogo psihosocial’nogo stressa na sostoyanie kostnoj tkani studentok medicinskogo universiteta [The influence of chronic psychosocial stress on the state of bone tissue of female students of the Medical University]. Vestn. KazNMU. – Bulletin Of The Kazakh National Medical University. 2013, no. 5 (1), рр. 233–236.
  6. Sharapov O,U., Zinov’ev E.V., Ivahnyuk G.K., Kolesova I.U., Garabadzhiu A.V. Kolichestvennye pokazateli soderzhaniya nekotoryh mikroelementov v kostyah visceral’nogo cherepa u krys na fone vvedeniya antioksidanta [Quantitative indicators of the content of certain trace elements in the bones of the visceral skull in rats against the background of the introduction of an antioxidant]. Fund. Issl. – Fundamental research. 2012, no. 10, рр. 356–358.
  7. Savinova N.V., Butolin E.G. Vliyanie hronicheskogo stressa na pokazateli obmena kollagena v kostnoj tkani krys s alloksanovym diabetom [The effect of chronic stress on collagen metabolism in rat bone tissue with alloxan diabetes]. Problemy Endokrinologii. – Problems of Endocrinology. 2004, no. 50 (1), рр. 49–51.
  8. Ivanov D.G., Aleksandrovskaya N.V. Vliyanie social’noj izolyacii na stressoustojchivost’ i rezorbciyu kostnoj tkani krys pri termicheskom stresse [The effect of social isolation on stress resistance and bone resorption in rats under thermal stress]. Biomedicina. – Biomedicine. 2018, no. 1, рр. 71–83.
  9. Davydova E.V., Plotnikova N.A., Slesarev V.O., Evstifeeva I.A., Aginosova O.G. Vliyanie immobilizacionnogo stressa pri perelome bedrennoj kosti na ryad pokazatelej perekisnogo okisleniya lipidov [The effect of immobilization stress in femoral fracture on a number of indicators of lipid peroxidation]. Elek. nauch.-obraz. vestn. «Zdorov’e i obrazovanie v XXI veke». – Online scientific and educational Bulletin “Health and education millennium”. 2008, vol. 10, no. 5, pp. 230–231.
  10. Lombardo G., Corrocher G., Migliorini L., Romoli L., Fiorino A. Stress kak faktor riska razvitiya periodontita (chast’ 2) [Stress as a risk factor of development of periodontitis (part 2)]. Stomatolog. Minsk. – Stomatologist. Minsk. 2012, no. 3 (6), pp. 10–25.
  11. Gorodeckaya I.V., Gusakova E.A. Vliyanie malyh doz L-tiroksina na ustojchivost’ k stressu zhivotnyh s eksperimetal’no vyzvannym deficitom simpaticheskih nervnyh vliyanij [The effect of low doses of L-thyroxine on the resistance to stress of animals with an experimetally induced deficiency of sympathetic nervous influences.]. Ros. fiz. zhur. im. I.M. Sechenova. – Journal of Evolutionary Biochemistry and Physiology. 2021, vol. 107, no. 3, pp. 352–373.

Correspondence to:  Е-mail: tanya.markevich86@mail.ru