Čes. stomatol. Prakt. zub. lék. (Czech Dental Journal) 2025; 125(1): 5-11 | DOI: 10.51479/cspzl.2025.001

ENDOGENOUSLY PRODUCED CHEMILUMINESCENCE OF INNER AND OUTER TOOTH STRUCTURES: A PILOT STUDY

Beneš P.^{1, 2}, Poplová M.³, Jirásek P^{1, 2}, Havelka D.³, Cifra M.³, Vacek J.⁴

¹ Klinika zubního lékařství, Lékařská fakulta Univerzity Palackého v Olomouci

² Klinika zubního lékařství, Fakultní nemocnice Olomouc

³ Výzkumný tým Bioelektrodynamika, Ústav fotoniky a elektroniky, Akademie věd ČR, v. v. i., Praha

⁴ Ústav lékařské chemie a biochemie, Lékařská fakulta Univerzity Palackého v Olomouci

Introduction: As a result of metabolic processes, the endogenous production of chemiluminescence occurs in living biological structures, which we also refer to as biological autochemiluminescence (BAL). The generation of BAL is closely connected with oxidation processes, the formation of free radicals, and in general the redox homeostasis of the investigated biological material. BAL has previously been studied in mammalian cells and tissues. So far, however, this phenomenon has not been described in dental tissue structures. In addition to endogenously generated BAL, BAL can be exogenously induced by physical (UV radiation, mechanical damage, heat), chemical (oxidizing agents, e.g. H₂O₂) or biotic (pathogens) factors.

Methods: Endogenously and exogenously induced BAL were investigated on the surface and internal structures of semi-impacted and impacted third molars, which were indicated for extraction by a dentist due to their inappropriate placement in the jaw in two patients (a 21-year-old woman and a 22-year-old man). BAL detection was performed with samples after dental plaque was mechanically removed with a rotating brush. Using a piezosurgery unit with a saw headpiece, longitudinal sections were made to reveal all internal parts of the tooth. The samples prepared in this way – the entire internal section and the external part of the entire tooth – were subjected to BAL detection in a dark chamber using H7360-01 PMT photomultiplier. Subsequently, the samples were treated with a solution of the oxidizing agent 3% H₂O₂ or the reducing agent 10 mM TCEP (tris(carboxyethyl)phosphine).

Results: Both tooth samples were shown to produce BAL. Endogenous chemiluminescence production was observed in the internal structures of the tooth (18,600 counts/600 s), which was 2.7-fold higher than the BAL detected on the tooth outer surfaces (6,900 counts/600 s). After H₂O₂ treatment, there was a significant (up to 14-fold) increase in BAL for internal tooth structures compared to the basal intensity of endogenously produced BAL. The application of TCEP (negative control) resulted in a residual suppression of BAL production.

Conclusion: The results of this pilot study show that BAL can be produced not only by soft tissues but also by hard dental tissue. The obtained results could be used for further research of the metabolic activity and reactivity of the inner and outer parts of the tooth, especially in the context of redox biology research. BAL detection could also be applied in the development of new imaging techniques.

Keywords: biological autochemiluminescence, tooth structures, oxidative stress

Received: October 24, 2024; Revised: January 6, 2025; Accepted: January 9, 2025; Prepublished online: February 27, 2025; Published: March 10, 2025  Show citation