Morphological evaluation of the fibrin framework in the treatment of dental pulp hyperemia: experimental study

INTRODUCTION. The complexity of the prognosis in the early and late stages of the conservative method of pulpitis treatment has limited its wide application. The article is aimed at studying and analyzing the potential of regenerative dentistry, which consists in restoring the function and structure of the dental pulp using innovative technologies. It is considered how biomaterials, fibrin framework (PRF) can be used to achieve this goal based on an experimental study and morphological assessment of the effect of these materials on the dental pulp. Platelet-rich fibrin (PRF) is a concentrate of platelets, which in recent years has become increasingly popular for regenerative procedures. An analysis of the materials used with appropriate conclusions is carried out.

AIM. To conduct a comparative morphological assessment of the use of modern bioactive materials and fibrin (PRF) as a scaffold in the treatment of pulp hyperemia.

MATERIALS AND METHODS. The experimental part of the study was performed on 8 white laboratory rats of 64 molars of teeth, Wistar lineage, of both sexes, with a body weight of 350–600 g, quarantined for at least 10–14 days, and kept in standard vivarium conditions of the Federal State Budgetary Educational Institution of Higher Medical Education of the Ministry of Health of the Russian Federation. The animals were divided into 4 groups – 2 individuals and 16 teeth in each group. Group 1 animals used fibrin (PRF) + “Trioxident” “Vladmiva”, Group 2 collagen membrane Geistlich Bio-Gide® + “Biodentine”, Group 3 fibrin (PRF) + “Biodentine” “Septodont”, Group 4 “Dycal” “Dentsply”. The experiment was conducted under anesthesia (protocol of the Ethics Committee of the Federal State Budgetary Educational Institution of Higher Education of the Ministry of Health of the Russian Federation No. 125 dated 09/12/2023). On the chewing surfaces of the 1 st and 2 nd molars, diamond carbide spherical borons were used to open the tooth cavity with partial pulp exposure. The formed cavity was treated with 0.05% chlorhexidine solution and dried. The test materials were then applied to the autopsy area. Experimental animals were removed from the experiment on days 3, 14, and 30. The resulting biological material was fixed in a 10% neutral formalin solution, decalcified, then poured into a histological medium and stained with hematoxylin and eosin according to Van Gieson. The sections were obtained on an Accu-Cut SRM 200 rotary microtome.

RESULTS. In the course of an experimental study in group 1 using fibrin (PRF) + Trioxidant in the area of contact with the therapeutic material, activation of reactive and compensatory processes in the tooth pulp tissue was detected while maintaining its viability for 30 days, which indicated the most pronounced regenerative potential among all the studied groups. As a result of a morphological assessment of micro-preparations of pulp with direct coating with “Dycal” material, group 4 showed that on the 30^th day the pathological process developed in the pulp is irreversible, because morphological changes were most pronounced: inflammatory infiltration with the presence of lymphocytes and neutrophils in the infiltrate, sclerotic changes, as well as granulation tissue and necrosis focus in the area of contact with the therapeutic material were noted.

CONCLUSIONS. The results of an experimental study conducted to compare histological changes in the pulp state with the use of various groups of materials in the near and long-term follow-up periods showed that the combined use of bioactive materials and fibrin (PRF) for direct coating of pulp increases the effectiveness of dental treatment with diagnoses of pulp hyperemia, and is also a promising direction in regenerative dentistry, due to the high the potential to influence the stimulation of reparative processes in the tooth pulp.

1. Adamchik A.A., Kirsh K.D., Ivashchenko V.A., Zaporozhskaya-Abramova E.S. Review of modern materials for the treatment of pulpal hyperemia. Endodontics Today. 2023;21(2):124-132. (In Russ.) https://doi.org/10.36377/1683-2981-2023-21-2-124-132

2. Vafiadi M.Yu., Sirak S.V., Shchetinin E.V., Balandina A.V., Ivaschenko V.A., Adamchyk A.A., Borodulina I.I. Experimental stimulation of reparative dentinogenesis after vital amputation of the pulp of the tooth. Medical news of the North Caucasus. 2019;14(1-2):171–176. (In Russ.) https://doi.org/10.14300/mnnc.2019.14008

3. Ivashchenko V.А., Adamchik A.А., Аrutyunov A.V., Risovanny S.I., Sidorenko A.N., Tsymbalov O.V. Morphological Changes in the Dental Pulp of Experimental Animals in the Treatment of Acute Partial Pulpitis using Modern Materials. Kuban Scientific Medical Bulletin. 2019;26(5):29–41. (In Russ.) https://doi.org/10.25207/1608-6228-2019-26-5-29-41

4. Nesterova M.M., Nikolaev A.I., Cepov L.M., Galanova T.A. Experience in the treatment of permanent teeth pulpitis by biological method. Clinical Dentistry (Russia). 2018;(1):16–19. (In Russ.) https://doi.org/10.37988/1811-153X_2018_1_16

5. Arandi N.Z. Calcium hydroxide liners: a literature review. Clin Cosmet Investig Dent. 2017;9:67–72. https://doi.org/10.2147/CCIDE.S141381

6. Anitua E., Sánchez M., Nurden A.T., Nurden P., Orive G., Andía I. New insights into and novel applications for platelet-rich fibrin therapies. Trends Biotechnol. 2006;24(5):227–234. https://doi.org/10.1016/j.tibtech.2006.02.010

7. Anitua E., Andia I., Ardanza B., Nurden P., Nurden A.T. Autologous platelets as a source of proteins for healing and tissue regeneration. Thromb Haemost. 2004;91(1):4–15. https://doi.org/10.1160/TH03-07-0440

8. Chanchareonsook N., Junker R., Jongpaiboonkit L., Jansen J.A. Tissue-engineered mandibular bone reconstruction for continuity defects: A systematic approach to the literature. Tissue Eng Part B Rev. 2014;20(2):147–162. https://doi.org/10.1089/ten.teb.2013.0131

9. Martin D.E., De Almeida J.F., Henry M.A., Khaing Z.Z., Schmidt C.E., Teixeira F.B., Diogenes A. Concentration-dependent effect of sodium hypochlorite on stem cells of apical papilla survival and differentiation. J Endod. 2014;40(1):51–55. https://doi.org/10.1016/j.joen.2013.07.026

10. Dombrovskaya Yu.A., Enukashvily N.I., Kotova A.V., Bilyk S.S., Kovalenko A.N., Silin A.V. Fibrin scaffolds containing dental pulp stem cells for the repair of periodontal bone defects. Translational Medicine. 2020;7(1):59–69. (In Russ.) https://doi.org/10.18705/2311-4495-2020-7-1-59-69

11. Pavlovic V., Ciric M., Jovanovic V., Trandafilovic M., Stojanovic P. Platelet-rich fibrin: Basics of biological actions and protocol modifications. Open Med. 2021;16(1):446–454. https://doi.org/10.1515/med-2021-0259