Difference in immune responses to Candida albicans in two inbred strains of male rats.

OBJECTIVE: To investigate the influence of strain differences in immune response on the pathogenesis of oral candidiasis in Dark Agouti (DA) and Albino Oxford (AO) inbred strains of rats. DESIGN: Seventy male 8-weeks old DA and AO rats were inoculated with Candida albicans to induce three different experimental models of oral candidiasis, one immunocompetent and two immunocompromised models. The animals were sacrificed after 16 days from the beginning of the experiment followed by collecting the samples of the tongue dorsum and blood for histopathological (PAS and H&E staining), immunohistochemical, qRT-PCR, and oxidative stress analyses. RESULTS: Histopathological and immunohistochemical analyses revealed lower levels of epithelial colonization, epithelial damage, and inflammatory infiltration in DA compared to AO strain of rats. DA rats had fewer CD45, CD68, and CD3 positive cells but more HIS 48 positive cells than AO rats. The expressions of IL-1ß, TNFα, IFN-γ, IL-10 and TGF-ß1 were consistently higher in DA strain across all experimental models. However, the expressions of IL-4 and IL-17 differed inconsistently between DA and AO strain in various experimental models. Strain differences were observed in levels of prooxidative hydrogen peroxide and lipid peroxidation, with higher levels presented in AO rats compared to DA rats, while antioxidative parameters presented little yet inconsistent difference between strains. CONCLUSION: DA strain of rats consistently presented lower susceptibility to oral infection with C. albicans compared to AO strain with robust Th1/Th17 immune response indicating the importance of the genetic background on the development of oral candidiasis.

Effects of direct pulp capping with recombinant human erythropoietin and/or mineral trioxide aggregate on inflamed rat dental pulp.

OBJECTIVE: This study aimed to evaluate the dental pulp responses to recombinant human erythropoietin (rhEPO) and/or mineral trioxide aggregate (MTA) in pulp capping of inflamed dental pulp in vivo. MATERIALS AND METHODS: In accordance with ARRIVE guidelines, pulp inflammation was induced by exposing the maxillary first molars (n = 64) of Wistar rats (n = 32) to the oral environment for two days. The exposed pulps were randomly assigned four groups based on the pulp capping material: rhEPO, MTA, MTA + rhEPO, or an inert membrane. An additional eight rats formed the healthy control group. After four weeks, the animals were euthanized, and histological, qRT-PCR, and spectrophotometric techniques were employed to analyze the left maxillary segments, right first maxillary molars, and blood samples, respectively. Statistical significance was set at p < 0.05 and < 0.001. RESULTS: Pulp capping with rhEPO, MTA, or MTA + rhEPO resulted in lower inflammation and higher mineralization scores compared to untreated control. MTA + rhEPO group exhibited significantly decreased expression of tumor necrosis factor-alpha, and interleukin 1-beta, while MTA group showed substantially reduced expression of interferon-gamma. Both rhEPO and MTA + rhEPO groups presented elevated dentin matrix protein 1 levels compared to untreated control. Furthermore, pulp capping with rhEPO and/or MTA led to increased transforming growth factor-beta 1 expression and reductions of pro-inflammatory/immunoregulatory cytokine ratios and prooxidative markers. Pulp capping with rhEPO also resulted in increase of systemic antioxidative stress markers. CONCLUSION: Capping with rhEPO or MTA + rhEPO resulted in a favorable effect that was similar or even superior to that of MTA.

The Evaluation of Healing Properties of Galium verum-Based Oral Gel in Aphthous Stomatitis in Rats.

Although oral ulcers represent one of the most frequent oral mucosal diseases, the available treatment is not sufficient to provide complete ulcer recovery without side-effects. Therefore, the aim of our study was to prepare a mucoadhesive oral gel based on Galium verum ethanol extract (GVL gel) and reveal its healing effects in the model of aphthous stomatitis in rats. Rats with oral ulcers were divided into the following groups: control (untreated), gel base (ulcer was treated with the gel base, three times per day for 10 days), and GVL gel group (the ulcer was treated with GVL gel in the same way as the gel base). Animals from each group were sacrificed on days 0, 3, 6, and 10 for collecting blood and ulcer tissue samples. Healing properties of oral gel were determined by clinical evaluation, as well as biochemical and histopathological examinations. Our findings suggest a significant decrease in the ulcer size in GVL gel group, with healing effects achieved through the alleviation of oxidative stress, reduction in COX-2 immunopositivity, and increase in collagen content in buccal tissue. Significant ulcer repairing potential of GVL gel highlights this oral mucoadhesive gel as a promising tool for prevention and treatment of RAS.

Application of the Kvaal Method in Age Estimation of the Serbian Population Based on Dental Radiographs.

This study aimed to evaluate the applicability of the Kvaal method in determining the age of a Serbian population. In this retrospective descriptive study, 170 dental patients (age range 16-77 years) were included. The measurements of six types of teeth were performed on digital orthopantomography radiographs according to the Kvaal method. Statistical inter-observer and intra-observer reliabilities were calculated to evaluate the reproducibility of the measurements, as well as to examine the correlation between chronological age and measured values. The evaluation revealed a substantial difference (over 12 years) between chronological and estimated age. The P ratio had the strongest correlation with chronological age for the maxillary central (r = ±0.293) and lateral incisors (r = ±0.240), whereas the pulp/root width ratio at level A had the strongest correlation for the mandibular first premolars (r = ±0.270). The lowest SD values, for measurements on teeth 15/25 (SD = 125,787), had the most accurate correlation with age. Thus, we can conclude that the original Kvaal method is not applicable in the age estimation of the Serbian population. For future research, we suggest using cone beam computer tomography as a precise technology to evaluate the applicability of Kvaal and other methods for age estimation.

The prevalence of oval-shaped root canals: A morphometric study using cone-beam computed tomography and image analysis software.

This study aimed to evaluate the prevalence of oval-shaped root canals at the apical, medial and coronal cross sections of all tooth groups using CBCT and image analysis software. Based on the diameter values, the long/short diameter ratio was calculated and each root canal was classified regarding its shape. Oval-shaped canals were present in 45% at the apical, 50% at the medial and 56% at the coronal level of all teeth. The mandibular central incisors presented oval canals in 24%, long oval in 28% and flat in 2% at the apical level. Mandibular molars showed a statistically significant difference (P < 0.05) in the distribution of oval-shaped canals between cross-sectional levels. Analysis of CBCT scans with an image analysis software could be a reliable and reproducible method and a valuable tool for objective determination of root canal shape in further research.