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In response to the growing interest in materials exhibiting magneto-dielectric coupling across diverse application domains, we present a detailed study on the electrical behavior of Ba0.1Bi0.9(Ti0.9Zr0.1)0.1Fe0.9O3 (BBTZF) ceramic. This study includes a comprehensive analysis of temperature- and frequency-dependent dielectric behavior, along with ac impedance properties. The thermo-dielectric study in the temperature range of 300–650 K suggests the presence of an anomaly near the Neel temperature (TN = 603 K), supporting the strong magneto-dielectric coupling in BBTZF. The differential thermal study also revealed an anomaly around TN, characterized by an exothermic peak. Furthermore, the well-described experimental dielectric data as a function of frequency (100 Hz–1 MHz), by the Cole–Cole relaxation equation modified by introducing complex conductivity, demonstrated a remarkable change in the frequency of relaxation (fr) as a function of temperature in the vicinity of TN. This change is attributed to the coupling between magnetic and electric order parameters. Through the complex impedance analysis recorded at different temperatures, it was found that both the capacitance and resistance of the grain showed a change in behavior around TN, suggesting that the magneto-electric coupling is predominantly of intrinsic origin in our material. Furthermore, the intrinsic magneto-capacitance grain value is approximately − 0.36%, highlighting its potential for application in magnetoelectric devices. Finally, the ac conduction study has shown that magnetic ordering can influence the translational hopping of large polaron mechanisms. [ABSTRACT FROM AUTHOR]

The clinical evidence, complications and the pathogenesis of COVID-19 are not clearly understood. In COVID-19 patients, cellular immune response biomarkers and oxidative stress parameters have been used as gravity markers. Indeed, oxidative stress has been proposed to play an essential role in the genesis of COVID-19. In the present research, we investigated lipid peroxidation, protein oxidation, superoxide dismutase activity and the production of auto-antibodies against superoxide dismutase, in the blood of Tunisian patients with corona virus. To evaluate lipid peroxidation, plasma malondialdehyde and conjugated dienes, have been determined in 69 corona virus patients and 30 controls. To determine protein oxidation the thiol level was measured. Plasma superoxide dismutase activity has been measured in 30 corona virus patients and 30 controls on one hand. Utilizing a standard enzyme-linked immunosorbent assay, the level of immunoglobulin G (IgG), and M (IgM) directed against superoxide dismutase was evaluated. To investigate the implication of auto-antibody production in COVID-19 patients in the generation of oxidative stress, a correlation study between auto-antibodies production and oxidative stress parameters was performed. High levels of both malondialdehyde and conjugated dienes were found in the plasma of patients (p < 0.001, respectively). Protein oxidation was confirmed by the high level of thiol (p < 0.001). Superoxide dismutase activity was not significantly lower in COVID-19 patients (p > 0.05). The level of immunoglobulin G (IgG), and M (IgM) directed against superoxide dismutase is significantly higher in COVID-19 patients than in control group (p < 0.001 respectively). Statistical analyses have demonstrated a positive correlation between superoxide dismutase activity and IgM and IgG isotypes antibodies level against superoxide dismutase (p < 0.001). A strong positive correlation was observed between IgG and malondialdehyde level in all cases (r = 0.368; p ≤ 0.01). In addition, a significant positive correlation was noted between IgM and malondialdehyde (r = 0.290; p = 0.024). Similarly, two significant positive relationship was found between IgG / conjugated dienes (r = 0.356; p = 0.005) and between IgM / conjugated dienes (r = 0.285; p = 0.027)., Competing Interests: Conflict of interestI declare that they have no conflict of interest related to the publication of this work., (© The Author(s), under exclusive licence to Springer Nature B.V. 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Deep learning has emerged as a powerful tool in medical imaging, particularly for corneal topographic map classification. However, the scarcity of labeled data poses a significant challenge to achieving robust performance. This study investigates the impact of various data augmentation strategies on enhancing the performance of a customized convolutional neural network model for corneal topographic map classification. We propose a hybrid data augmentation approach that combines traditional transformations, generative adversarial networks, and specific generative models. Experimental results demonstrate that the hybrid data augmentation method, achieves the highest accuracy of 99.54%, significantly outperforming individual data augmentation techniques. This hybrid approach not only improves model accuracy but also mitigates overfitting issues, making it a promising solution for medical image classification tasks with limited data availability., (© 2025 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

In this paper, an automated feature selection (FS) method is presented to optimize machine learning (ML) models' performances, enhancing early keratoconus screening. A total of 448 parameters were analyzed from a dataset comprising 3162 observations sourced from the swept source optical coherence tomography imaging system developed by the Chinese Academy of Sciences Institute of Automation (SS-1000 CASIA OCT) and electronic health records (EHR). To identify the most relevant features, the analysis of variance (ANOVA) method was used in this study. The performance of three classifiers namely K-Nearest Neighbors (KNN), Support Vector Machine (SVM), and Artificial Neural Networks (ANN) was evaluated, yielding classification accuracies of 96.79% and 96.68% for KNN, 98.95% and 97.08% for SVM, and 95.64% and 95.62% for ANN when distinguishing between 2 and 4 keratoconus classes, respectively. The results show that selecting 50 features can significantly improve the performance of the model while reducing the computation time. The automated feature selection method can also assist ophthalmologists in better understanding the links between various ocular characteristics and keratoconus, potentially leading to advances in early diagnosis, risk prediction, and clinical management of this condition., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

Addressing a single target is the frequent development of drug resistance followed by cancer relapse and treatment failure. Therefore, assessment of simultaneous expression of target molecules is essential to choose the optimal combination therapy for each colorectal cancer patient. This study aims to evaluate the immunohistochemical expression of HIF1α, HER2 and VEGF and to clarify their clinical significance as prognostic factors and predictive markers of FOLFOX (combination chemotherapy inclusive of Leucovorin calcium, Fluorouracil and Oxaliplatin response). Marker expression was retrospectively evaluated by immunohistochemistry in 111 patients with colorectal adenocarcinomas from south Tunisia, followed by statistical analysis. The immunohistochemical staining revealed that 45 %, 80.2 %, 86.5 % and 25.5 % of specimen were positive for nuclear, cytoplasmic HIF1α expression, VEGF and HER2 respectively. Nuclear HIF1α and VEGF were associated with worst prognosis while cytoplasmic HIF1α and HER2 were correlated with favourable prognosis. Multivariate analysis confirms the association between nuclear HIF1α, distant metastasis, relapse, FOLFOX response and 5 years overall survival. HIF1α positivity and HER2 negativity were significantly associated to short survival. Combined immunoprofiles HIF1α+/VEGF+, HIF1α+/HER2-, HIF1α+/VEGF+/HER2- were associated to distant metastasis, cancer relapse and short survival. Interestingly, our findings confirmed that patients bearing a HIF1α positive tumor were significantly more resistant to FOLFOX compared to negative ones (p = 0.002, p ≤ 0.001). Positive expression of HIF1α and VEGF, or decreased expression of HER2 was each associated with poor prognosis and short overall survival. In summary, we found that expression of nuclear HIF1α, alone or combined with VEGF and HER2 serves as a predictive marker of poor prognosis and FOLFOX response in colorectal cancer from south Tunisia., Competing Interests: Declaration of competing interest The author (s) declared no potential conflicts of interest., (Copyright © 2023. Published by Elsevier Inc.)

Background: The contribution of viral infection in tumors pathogenesis has currently attracted attention. Epstein-Barr virus is an infectious agent involved in numerous human malignancies, including breast cancer. Although, their prognostic impact in breast tumor is rarely investigated. Therefore, we sought in our study to evaluate the prevalence of EBV in Tunisian breast carcinoma and to examine their potential association with clinicopathological features and overall survival., Methods: Our retrospective study included 100 formalin fixed paraffin embedded samples from Tunisian breast carcinoma. EBV infection was evaluated by immunohistochemical analysis, using monoclonal antibody against latent membrane protein 1 (LMP-1) and polymerase chain reaction. A subset of PCR positive specimens was subjected to in situ hybridization for the detection of EBER expression. Biomarker's expression was evaluated by immunohistochemistry method. Statistical analysis was also explored., Results: The expression status of ER, PR and HER2 was 81%, 71.4% and 33.7% respectively. The triple negative profile was present in 10.84% of cases. LMP-1 expression was negative in all breast cancer specimens. PCR assay showed that 44% of patients were positive for EBV genome. None of the 15 PCR positive cases showed positive results for EBV by ISH. According to the molecular phenotype, there was a statistically significant difference in EBV DNA prevalence between breast cancer subgroups including TN (67%), Lum B (64%), HER2 + (50%) and Lum A (30%). Bivariate analysis showed that EBV DNA was significantly associated with HER2 + (p = 0.035), tumor size (p = 0.018) and high SBR grade (p = 0.009). Multiple logistic regression analysis confirms the positive correlation of EBV with tumor size (p = 0.048) and SBR grade (p = 0.042). Kaplan-Meier analysis showed that patients with EBV+ had significantly shorter overall survival than those with EBV- (p = 0.032)., Conclusions: Our study demonstrated the presence of EBV DNA in Tunisian breast carcinoma. EBV DNA was associated with aggressive features and poor overall survival. Further investigations will be required in large samples size to clarify the potential role of EBV in breast tumor progression., Competing Interests: Conflict of interest The authors declared no potential conflicts of interest., (Copyright © 2023 Elsevier GmbH. All rights reserved.)

The current research work attempted to investigate, for the first time, the impact of biochar addition, on anaerobic digestion of olive mill wastewater with different initial chemical oxygen demand loads in batch cultures (10 g/L, 15 g/L, and 20 g/L). Methane yields were compared by applying one-way analysis of variance (ANOVA) followed by post-hoc Tukey's analysis. The results demonstrated that adding at 5 g/L biochar to olive mill wastewater with an initial chemical oxygen demand load of 20 g/L increased methane yield by 97.8% and mitigated volatile fatty acid accumulation compared to the control batch. According to the results of microbial community succession revealed by the Illumina amplicon sequencing, biochar supplementation significantly increased diversity of the microbial community and improved the abundance of potential genera involved in direct interspecies electron transfer, including Methanothrix and Methanosarcina . Consequently, biochar can be a promising alternative in terms of the recovery of metabolic activity during anaerobic digestion of olive mill wastewater at a large scale., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Abid, Karray, Kallel, Slim, Barakat, Mhiri, Chamkha and Sayadi.)

Background: Citrus fruits have been a valuable economic crop for thousands of years. Furthermore, citrus essential oils are significant in the perfume, food, and beverage sectors, as well as aromatherapy and medical medicines., Aims: The present study aims to evaluate the phytochemical and pharmacological potentials of the optimized Citrus sinensis 'Maltese half-blood' essential oils peels (CsEO) extraction yields using Response-Surface Methodology (RSM)., Objective: There have been few investigations on Citrus sinensis 'Maltese half-blood' essential oil., Methods: Citrus sinensis 'Maltese half-blood' essential oil peels (CsEO) extraction yields were performed by hydro-distillation and optimized by using Response-Surface Methodology (RSM). The oils were analysed by GC-MS. Different chemical tests were used to evaluate antioxidant activities. The healing potential was evaluated using models' wounds on Wistar rats., Results: The RSM optimization demonstrated the highest yield of CsEO of 6.89 g/100 g d.b. All three tested factors significantly influenced the CsEO extraction yield: washing saline solution concentration, washings number, and drying percentage of peels. Significant antioxidant activities were noted in CsEO: the DPPH assay reported an IC 50 of 0.225 ± 0.014 mL/mg, the FRAP assay showed an IC 50 of 0.235 ± 0.001, and the NO assay was an IC 50 in order of 0.259 ± 0.019. CsEO was not genotoxic and considerably decreased the levels of DNA lesions induced by oxidants. Also, applying a cream with CsEO on wounds promotes significantly rapid wound healing., Conclusion: CsEO could be considered a rich natural source of antioxidants and bio-compounds to accelerate wound healing. It can be used in pharmaceutical sectors as an alternative to synthetic chemicals., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Olive pomace is the main by-product generated by the olive oil production process. Although toxic to the environment, olive pomace is an important source of natural antioxidants due to its high content of phenolic compounds. The aim of the current study is to maximize the extraction yields of the main phenolic compounds present in olive pomace using innovative green technologies. For this purpose, the present work is divided into two parts. The first part is based on a solubility study of targeted phenolic compounds in various ethanol/water ratios at two different temperatures (20 °C and 50 °C). A computational prediction using COSMO-RS software was applied for the calculation of eventual solubility, which was subsequently confirmed by practical experiments. The determination of the optimal extraction conditions of solvent ratio (EtOH/H 2 O) (60:40 v / v ) and temperature (50 °C) led to the second part of the work, which concerns the intensification of extraction yields. Furthermore, various green extractions using innovative technologies, including accelerated solvent extraction (ASE), ultrasound with its both system (probe (UAE-P) and bath (UAE-B)), bead milling (BM) and microwave (MAE), were carried out and then compared to conventional maceration (CM). Results showed that ASE was the most effective method for extracting phenolic compounds from dried olive pomace powder (5.3 milligrams of tyrosol equivalent (TE) per gram of dried olive pomace powder (DOP)) compared to CM (3.8 mg TE/g DOP).

Punica granatum is a rich source of bioactive compounds which exhibit various biological effects. In this study, pomegranate peel and leaf ethanolic crude extracts (PPE and PLE, respectively) were phytochemically characterized and screened for antioxidant, antimicrobial and antiviral activity. LC-PDA-ESI-MS analysis led to the identification of different compounds, including ellagitannins, flavonoids and phenolic acids. The low IC 50 values, obtained by DPPH and FRAP assays, showed a noticeable antioxidant effect of PPE and PLE comparable to the reference standards. Both crude extracts and their main compounds (gallic acid, ellagic acid and punicalagin) were not toxic on Vero cells and exhibited a remarkable inhibitory effect on herpes simplex type 1 (HSV-1) viral plaques formation. Specifically, PPE inhibited HSV-1 adsorption to the cell surface more than PLE. Indeed, the viral DNA accumulation, the transcription of viral genes and the expression of viral proteins were significantly affected by PPE treatment. Amongst the compounds, punicalagin, which is abundant in PPE crude extract, inhibited HSV-1 replication, reducing viral DNA and transcripts accumulation, as well as proteins of all three phases of the viral replication cascade. In contrast, no antibacterial activity was detected. In conclusion, our findings indicate that Punica granatum peel and leaf extracts, especially punicalagin, could be a promising therapeutic candidate against HSV-1.

Lateral luxation is defined as a traumatic displacement of a tooth in any direction other than axially. A laterally luxated tooth is often immobile because of its bony lock. It produces a high metallic sound during percussion. Pulp sensibility testing is likely to be negative during the initial follow-up. However, the tooth should be monitored until a definitive pulp diagnosis is made. Treatment includes local anesthesia, suturing soft tissue injuries, manual repositioning of the luxated tooth, and stabilization with a flexible splint for 4 weeks. Given the risk of pulp necrosis following lateral luxation, particularly in teeth with radiographically closed apices and severe displacement, an immediate (prophylactic) root canal treatment is recommended. The objective of this work was to report and discuss the management of a case of lateral luxation involving a permanent tooth treated by reduction, followed by contention with 0.4 steel wire and composite resin, and endodontic treatment, and which was complicated by root resorption 3 months later. We also highlighted the possible complications following lateral luxation, especially root resorption., Competing Interests: No conflicts of interest., (© 2022 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.)

Colorectal cancer (CRC) is a common health issue worldwide with an extremely low survival rate after relapse. This study aims to evaluate the immunohistochemical expression of p53, E-cadherin, Bcl-2 and Bcl-xL and find a potential correlation between these markers, clinicopathological factors and overall survival of colorectal cancer patients. Marker expression was immunohistochemically determined in 105 patients with colorectal adenocarcinoma from southern Tunisia, followed by statistical analysis. Positivity rate of nuclear p53, membranous E-cadherin and cytoplasmic Bcl-2 - Bcl-xL was 85.71%, 76.47%, 59.8%, and 85.71% respectively. Spearman correlation showed that p53 was significantly and positively related to E-cadherin, Bcl-2, Bcl-xL and distant metastasis. A positive significant correlation between E-cadherin and anti-apoptotic proteins was also seen. Membranous E-cadherin expression was significantly and negatively associated to poor prognosis factors including lymph node metastasis, lymph invasion, venous invasion and distant metastasis. Bcl-2 expression was significantly correlated to distant metastasis. Multivariate analysis showed a significant association between dependent variable E-cadherin and covariates including differentiation, lymph invasion, venous invasion, distant metastasis, Bcl-2 and Bcl-xL. Poor 3-years OS and 5-years OS were significantly related to p53, Bcl-2 expression and E-cadherin loss. Positive E-cadherin combined with negative p53 and Bcl-2 as well as double-positive for E-cadherin and Bcl-xL were associated to best overall survival. Although each protein can be an independent prognostic factor, Simultaneous E-cadherin, p53, Bcl-2, Bcl-xL expression could be a crucial prognostic and overall survival marker to CRC patients. Multivariate analysis confirmed a positive correlation between membranous E-cadherin loss and colorectal cancer severity.

The management of deep carious lesions in immature tooth and the preservation of its pulp vitality is a real challenge in daily dental practice. Bioactive cements are of interest to deal with such cases. Our case report describes the immediate management and the follow-up of an extensive carious lesion on an immature first right mandibular molar with pulp exposure by direct pulp capping using Biodentine. A 6-month clinical and radiographic follow up showed that the tooth was vital, with dentine-bridge formation in the pulp chamber with continuous root formation. This procedure allowed the protection of pulp complex, preserving at the same time its functional and biologic activities due to the capacities of Biodentine as an effective pulp capping material to induce pulp cells to form hard tissue. The aim of this article is to discuss through the report of this clinical case, the indications, advantages and disadvantages of different procedures and biomaterials used for direct pulp capping., Competing Interests: Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

Olea europaea L. var. sativa (OESA) preparations are widely used in traditional medicine in the Mediterranean region to prevent and treat different diseases. In this research, olive extracts derived from the leaves of the OESA tree have been screened for antioxidant activity by two methods: the DPPH free radical scavenging assay (DPPH) and the Ferric reducing antioxidant power (FRAP) assay. The DPPH assay showed that OESA possesses a stronger antioxidant activity (84%) at 1 mg/mL while the FRAP method showed a strong metal ion chelating activity (90%) at 1 mg/mL. The low IC 50 values, obtained by two different methods, implies that OESA has a noticeable effect on scavenging free radicals comparable to standards. During EBV infection, the free radicals increased triggering lipid oxidation. Therefore, the monitoring of the secondary lipid peroxidation products was done by measuring malonaldehyde (MDA) and conjugated dienes (DC). The simultaneous treatment of Raji cells with OESA and TPA, as an inductorof the lytic cycle, generated a significant decrease in MDA levels and DC ( p < 0.05). Besides, Raji cells simultaneously exposed to TPA and OESA exhibited a percentage of EBV-positive fluorescence cells lower than TPA treated cells (**** p < 0.0001). This suggests that OESA treatment has a protective effect against EBV lytic cycle induction.

Background: Cathepsin D (CTSD) is an aspartyl proteinase that plays an important role in protein degradation, antigen processing and apoptosis. It has been associated with several pathologies such as cancer, Alzheimer's disease and inflammatory disorders. Its function in lung diseases remains, however, controversial. In the current study, we determined CTSD activity in serum of patients with chronic obstructive pulmonary disease (COPD) and evaluated the correlations between this proteinase and inflammatory and oxidative parameters. We also investigated the impact of a CTSD C224T polymorphism on enzyme activity and clinicopathological parameters., Methods: Our population included 211 healthy controls and 138 patients with COPD. CTSD activity, MMPs (-1/-7/-12), cytokines (IL-6, TNF-α), malondialdehyde (MDA), nitric oxide and peroxynitrite levels were measured in patients and controls using standard methods. Genotyping of CTSD C224T polymorphism was determined using PCR-RFLP., Results: Our results showed an increased CTSD activity in COPD patients compared to healthy controls (4.87 [3.99-6.07] vs. 3.94 [2.91-5.84], respectively, p < 0.001). COPD smokers presented also a higher CTSD activity when compared to nonsmokers (4.91[3.98-6.18] vs. 4.65[4.16-5.82], respectively, p = 0.01), while no differences were found when subjects were compared according to their GOLD stages. The activity of this proteinase was not dependent on the C224T polymorphism because we did not found any influence of this SNP on proteinase activity among patients and controls. Furthermore, our data provide the first evidence of the interrelationships between CTSD activity and both MMPs and TNF-α levels (MMP-1[r = - 0.4; p = 0.02], MMP-7[r = 0.37; p = 0.04], MMP-12[r = 0.43; p = 0.02], TNF-α [r = 0.89, p = 0.001]) in COPD smokers. There were no correlations, however, between CTSD activity and oxidative stress parameters in controls and patients., Conclusion: Our findings suggest that CTSD could be a relevant marker for COPD disease. Alteration of CTSD activity may be related to increased MMPs and TNF-α levels, particularly in COPD smokers.

Objective: The aim of this clinical study was to evaluate the effectiveness of a whitening toothpaste containing 3% carbamide peroxide and lactoperoxidase. Materials and methods . Participants were instructed to brush their teeth using an enzymatic-activated dentifrice following a particular procedure for three weeks. Color was recorded before and after treatment using a VITA Easyshade spectrophotometer. Differences in L ∗ (tooth color lightness), a ∗ (displacement along the red-green axis), and b ∗ (displacement along the yellow-blue axis) were measured before and after treatment using the paired t and the Wilcoxon signed-rank tests. Color changes (Δ E ) were calculated using the obtained measurements., Results: Thirty-four volunteers were included. Δ E was 4.03. For the set of 348 teeth, a greater tendency towards green (lower a ∗ ) and blue (lower b ∗ ) was observed ( p  < 0.05). There were no significant differences in lightness after treatment. Mandibular central incisors showed a greater tendency towards green (lower a ∗ ) and blue (lower b ∗ ). Bleaching effectiveness was observed in both the upper and lower central incisors and in the lateral mandibular incisors., Conclusion: Based on these results, it may be concluded that brushing with an enzymatic-activated dentifrice is effective for whitening teeth., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Mehdi Khemiss et al.)

Objectives: This work aimed to estimate the knowledge and practice of general dentists in the governorate of Manouba regarding the management of patients at risk of infective endocarditis., Materials and Methods: A survey involving private sector general dentists in the governorate of Manouba was performed. It contained 21 questions, and it was addressed to 111 dentists. Only 82 dentists responded. To carry out the descriptive study, we used the SPSS software version 21.0., Results: Our results proved the lack of knowledge among dentists in the governorate of Manouba with regard to the management of patients at risk of infective endocarditis. An overestimation of the risk and an overprescription of antibiotic were found in order to ensure an over-protection for the patients as well as the dentist. In fact, 85.4% of these dentists prescribed antibiotic prophylaxis for the two groups of patients (high risk and moderate risk). Only 9.8% followed the right modality of antibiotic prophylaxis prescription; 4.9% of the dentists prescribed antibiotic only 1 hour before the act and 4.9% of them prescribed antibiotic 1 hour before the act and continued the treatment in case of the presence of an infectious site., Conclusion: A discrepancy towards an over-estimation of risk and overprescription of antibiotic was found between the recommendations and real practice. Similar studies in the other governorates of Tunisia are recommended in order to better understand the problem., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Malek Lagha et al.)

An odontogenic cutaneous sinus tract is a pathologic canal that initiates in the oral cavity but opens externally at the cutaneous surface of the face or neck. It is frequently misdiagnosed, leading to inappropriate treatment. A 44-year-old female patient referred to us with a chronically draining lesion on his chin. The lesion previously was misdiagnosed by medical doctors and had undergone cryotherapy and surgery with a focus on the skin lesion and had received antibiotic therapy for a prolonged period of time. After clinical and radiologic examination the dental origin of the lesion was evident and proper endodontic treatment was performed followed by surgical treatment after the recurrence of pus discharge 2 weeks after the conventionnel root canal treatment. Five months later, after the treatment, the lesion showed an obvious healing. After 18 months, the patient was comfortable and a significant healing of the sinus tract was noted, the periapical radiograph shows clear regression of the periapical lesion and an improvement in bone trabeculation. The key to successful treatment of cutaneous sinus tract of dental origin must be appropriate communication between the dentist and the physician in order to achieve correct diagnosis and therapy in such cases., Competing Interests: There are no conflicts of interest., (Copyright: © 2021 Journal of Conservative Dentistry.)

Periostitis ossificans is a chronic disease characterized by an ossifying periostitis, occurring in children and young adults, commonly as a reaction to a mild infection or irritation. It is also characterized by the presence of lamellae of newly formed periosteal bone outside the cortex, giving the characteristic radiographic appearance of "onion skin." Aim . The aim of this paper was to present the clinical and radiographic findings, as well as the postoperative follow-up of two cases diagnosed with periostitis ossificans of dental origin, and to discuss the differential diagnosis and treatment modalities. Case Reports . In the first case, a 16-year-old adolescent was referred for a persistent mandibular swelling. Intraoral examination showed two sinus tracts in relation to the carious necrotic left mandibular first molar. The periapical radiograph showed a periapical lesion in relation to the two root canals of the left mandibular first molar. Occlusal radiographs revealed the "onion skin" bone formation aspect. In the second case, a 10-year-old girl presented to our department with a slightly painful mandibular swelling. The periapical radiograph showed a periapical lesion in relation to both the mesial and distal roots of the carious necrotic right mandibular first molar. Cone beam computed tomography (CBCT) showed a subperiosteal bone formation with an "onion skin" aspect. Diagnosis of periostitis ossificans in the two cases was confirmed and the lesion was resolved by simply an endodontic treatment. Conclusion . Specific attention should be given to clinical and radiographic exploration in case of children with mandibular swelling. As osteosarcoma can be misdiagnosed, additional examinations, such as computed tomography, can be useful in differential diagnosis and in searching malignancy signs., Competing Interests: The authors declare that there is no conflict of interests., (Copyright © 2020 Hana Bougatef et al.)