The Association Between Genetic Variants in ACE1and ACE2 Genes with Susceptibility to COVID-19 Infection.

Angiotensin-converting enzyme 2 (ACE2) receptors facilitate the entry of the causative virus severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) into target cells. Some ACE gene variants have been suggested to be involved in COVID-19 pathogenesis. So, the aim was to assess the association between ACE1 rs4646994 and ACE2 rs2285666 genes polymorphisms and the susceptibility and severity of COVID-19. This case-control study was conducted on 197 patients with COVID-19 and 197 healthy controls. ACE-1 insertion/deletion (I/D) (rs4646994) and ACE2 rs2285666 genes polymorphisms were determined by the amplification refractory mutation system- polymerase chain reaction (ARMS-PCR) technique. The DD genotype of ACE1 I/D polymorphism was associated with increased susceptibility to COVID-19 infection (p = 0.012), whereas the ID genotype of this polymorphism was associated with decreased susceptibility (p = 0.003) (significance level = 0.017). There was no significant association in allele and genotype distribution of ACE2 rs2285666 polymorphism between cases and controls. The ACE1 I/D polymorphism may be considered as a risk factor for COVID-19 susceptibility.

Gene polymorphisms and prognosis of head and neck squamous cell carcinoma: a systematic review.

Background: Head and neck squamous cell carcinomas (HNSCCs) are associated with variable prognosis even with similar clinical characteristics and treatments. Gene polymorphisms have been suggested as prognostic factors for HNSCC which can justified this variable prognosis. So, the aim was to review literatures on gene polymorphisms and prognosis of HNSCCs. Materials and methods: A systematic search was conducted using PubMed, Web of science, SCOPUS, Google Scholar and Cochrane library databases to find all related articles published up to December 2021 in the field of gene polymorphisms and HNSCC prognosis. Results: Of 1029 initial searched articles, 71 articles were selected for inclusion in this systematic review. About 93 genes and 204 polymorphisms have been discussed in these articles. Among the most studied polymorphisms, the XRCC1 Arg399Gln and Arg194Trp polymorphisms were not associated with survival in most studies; the ERCC1 C19007T polymorphism had no significant association in any of the studies. Different gene polymorphisms of glutathione s-transferase family, including GSTM1 deletion, GSTT1 deletion and GSTP1 A313G, were not associated with survival in included studies. There are conflicting results regarding the association between polymorphisms such as ERCC2 A35931C, Asp312Asn, ERCC5 rs1047768 and rs17655 with HNSCC prognosis. Less studied polymorphisms, such as hOGG1 rs1052133 or the VEGF rs699947, were generally not associated with HNSCC prognosis. Conclusion: Reviewed articles reported varied and contradictory results regarding the association of gene polymorphisms and HNSCC prognosis, which necessitates further studies along with meta-analysis on the results of such studies.

Gene polymorphisms and risk of head and neck squamous cell carcinoma: a systematic review.

Background: Exposure to the same environmental factors in different people have resulted in different susceptibility to head and neck squamous cell carcinoma (HNSCC), which suggests genetic variation may be a risk factor for the development of HNSCC. So, the aim was to review literatures on the association between gene polymorphisms and risk of HNSCCs. Materials and methods: This systematic review included all articles on the impact of gene polymorphisms on risk and susceptibility to HNSCC published till September 2021 using PubMed, Web of science, SCOPUS, Google Scholar and Cochrane library databases. Results: Of 1163 initial searched articles, 77 articles were eligible to include in this review. Studies were categorized based on gene functions. In each category, studied gene polymorphisms related to growth control genes, cell cycle control, apoptosis, DNA repair genes, carcinogen-metabolizing enzymes, alcohol-metabolizing genes, antioxidant gene, inflammatory cytokine, transcription factor, tumor immunity, folate metabolism, and tumor suppressor gene were discussed separately. Among the polymorphisms that are often significantly associated with HNSCC risk are: GSTM1 null, GSTT1 null, CYP2D6 *4, XRCC1 Arg194Trp and Arg399Gln, ERCC1 C8092A, XPD Lys751Gln, XRCC3 Thr241Met, P53 codon 72 and MTHFR C677T polymorphisms. Conclusion: Varied and contradictory results have been reported in different studies regarding the association of gene polymorphisms with HNSCC risk. To conclude about this association and to overcome these contradictions, it is necessary to use the results of existing meta-analyses or to perform new or updated meta-analyses.

Prevalence of human papillomavirus (HPV) in oral mucosal lesions in Iran: A systematic review and meta-analysis.

The role of human papillomavirus (HPV) in the development of oral lesions is controversial. There has been no comprehensive study about HPV prevalence in Iran. This systematic review and meta-analysis were aimed at finding HPV prevalence of oral lesions and normal oral mucosa in Iran. International (PubMed, Web of Science, and Scopus) and national (Iranmedex, Irandoc, and SID) databases were searched systematically until October 2020. Studies that examined the prevalence of HPV in oral lesions by polymerase chain reaction method were included. The heterogeneity of articles was assessed with the Cochran test and I-Square statistics. The prevalence rate of HPV was calculated using a random-effect model. Of 3729 initially searched articles, 29 articles were eligible for inclusion. The overall prevalence of HPV in oral lesions was 21%. The prevalence was the highest in Rasht (50%) city. Lip lesions had the highest HPV prevalence (40%). According to the classification of lesions, the highest prevalence was of precancerous lesions (29%) and the lowest in normal mucosa (8%). Well-differentiated tumors showed a higher prevalence than poorly-differentiated ones. The highest prevalence of HPV was hairy leukoplakia (70%) and the lowest was of pyogenic granuloma (6%). Also, the prevalence was 31% in oral squamous cell carcinoma. There are differences between HPV prevalence according to the geographical area, intraoral location, type of lesion, and grading. As HPV prevalence was fairly high, further attention to vaccination and treatment for HPV in Iran, as a potential risk factor for oral precancerous and cancerous lesions is recommended.

Actinomycotic Osteomyelitis of Mandible.

Actinomycosis is an infection of filamentous, gram-positive anaerobic bacteria. Actinomycosis of jaw bone is rare and the diagnosis is often difficult. The aim of this patient report is to present an actinomycotic osteomyelitis of mandible in a 30-year-old male patient. The patient presented with a chief complaint of pain and unhealed dental socket after mandibular teeth extractions. Radiographs showed ill-defined radiolucencies and perforation of buccal and lingual cortical plate; several biopsies and different therapy could not improve the lesion because of fault diagnosis and improper treatment. Finally, the authors' histopathological examination revealed granulation tissue surrounded bacterial colonies compatible with actinomycotic colonies. Follow-up examinations showed that the patient was well 6 months after prolonged treatment without any pain and discharge from dental socket.

Comparison the salivary streptococcus mutans levels between caries-active and caries-free children from Birjand, Iran: A case-control study.

Objective: Dental plaque bacteria, including Streptococcus mutans (SM), play a role in the pathogenesis of the dental caries. There are conflicting results regarding the association of salivary SM level and dental caries susceptibility. Our aim was to compare salivary SM levels in colony-forming units (CFU) between children with active caries and caries-free children in Birjand, Iran. Methods: This case-control study included 61 six-year-old children referred to health centers in Birjand city, Iran, in 2022. The children were divided into two groups: case (dmft/DMFT>0 with active caries) (including 31 children) and control (dmft/DMFT = 0 [caries-free]) (including 30 children). Demographic information and dental history were recorded. Oral examinations were also performed by the dentist. Unstimulated saliva samples were collected from children. The number of salivary SM colonies was determined using the microbial culture and confirmed using the polymerase chain reaction (PCR). The data were analyzed using Chi-square and T-tests at a significance level of p < 0.05. Results: The mean number of SM colonies was 126.24 ± 92.78 CFU/ml and 92.38 ± 75.34 CFU/ml in case and control groups, respectively. No significant difference was found in salivary SM levels between case and control groups (P = 0.125). No significant association was observed between caries experience with gender (P = 0.363), type of school (public/private) (P = 0.296), receiving oral health education (P = 0.072) and frequency of tooth brushing (P = 0.935). The mean gingival index (P = 0.001) and plaque index (P = 0.025) in case group were significantly higher than control group. Conclusion: There is no significant difference in salivary SM levels between caries-active and caries-free children in Birjandi children.

The XRCC1 Arg194Trp polymorphism was associated with the risk of head and neck squamous cell carcinoma development: Results from a systematic review and meta-analysis.

BACKGROUND: The X-ray repair cross complementing group 1 (XRCC1) is a DNA repair gene. Various studies have examined the association between XRCC1 Arg194Trp polymorphism and head and neck squamous cell carcinoma (HNSCC) susceptibility with contradictory results. So, this systematic review and meta-analysis aimed to assess whether variants of this polymorphism increase the HNSCC risk or not. RECENT FINDINGS: Thirty three studies consisting of 14282 subjects (6012 cases and 8270 controls) were included in this meta-analysis. Variants of XRCC1 Arg194Trp polymorphism were associated with increased HNSCC risk and the associations were significant based on heterozygous and dominant models (heterozygous model: OR = 1.182, 95%CI = 1.015-1.377, P = 0.032; homozygous model: OR = 1.274, 95%CI = 0.940-1.727, P = 0.119; dominant model: OR = 1.194, 95%CI = 1.027-1.388, P = 0.021; recessive model: OR = 1.181, 95%CI = 0.885-1.576, P = 0.119). There were significant associations between variants of this polymorphism and HNSCC risk based on Asian ethnicity under dominant model, hospital control source under different genetic models, PCR-RFLP genotyping method under dominant model and oral cavity tumor site under heterozygous and dominant models. OBJECTIVE: The X-ray repair cross complementing group 1 (XRCC1) is a DNA repair gene. Various studies have examined the association between XRCC1 Arg194Trp polymorphism and head and neck squamous cell carcinoma (HNSCC) susceptibility with contradictory results. So, this systematic review and meta-analysis aimed to assess whether variants of this polymorphism increase the HNSCC risk or not. METHODS: A systematic search of the literatures published till April 2022 was conducted using Google Scholar, Scopus, PubMed, Web of Science, Cochrane Library and Embase databases. The heterogeneity was assessed with the I-Square statistic. A random effects model or fixed effects model was used to analyze the data. Data were reported by odds ratio (OR) and 95% confidence interval (CI). The p value was considered significant if p < .05. RESULTS: Thirty three studies consisting of 14 282 subjects (6012 cases and 8270 controls) were included in this meta-analysis. Variants of XRCC1 Arg194Trp polymorphism were associated with increased HNSCC risk and the associations were significant based on heterozygous and dominant models (heterozygous model: OR = 1.182, 95%CI = 1.015-1.377, p = .032; homozygous model: OR = 1.274, 95%CI = 0.940-1.727, p = .119; dominant model: OR = 1.194, 95%CI = 1.027-1.388, p = .021; recessive model: OR = 1.181, 95%CI = 0.885-1.576, p = .119). There were significant associations between variants of this polymorphism and HNSCC risk based on Asian ethnicity under dominant model, hospital control source under different genetic models, PCR-RFLP genotyping method under dominant model and oral cavity tumor site under heterozygous and dominant models. CONCLUSION: Variants of XRCC1 Arg194Trp polymorphism were significantly associated with increased risk of HNSCC development based on heterozygous and dominant genetic models.

Association between XRCC1 Arg399Gln polymorphism with prognosis of head and neck squamous cell carcinomas: A meta-analysis.

Objective: The X-ray repair cross complementing group 1 (XRCC1) gene is involved in DNA repair. Defects in DNA repair may lead to head and neck squamous cell carcinomas (HNSCCs). Several researches have focused on relationship between XRCC1 Arg399Gln genetic polymorphism with HNSCC's prognosis with conflicting results. So, the aim of the present meta-analysis was evaluation of relationship between XRCC1 Arg399Gln polymorphism with HNSCC's prognosis. Methods: Published articles up to July 2022 were systematically searched through international databases like PubMed, Web of Science, Scopus, etc. I2 test was applied to assess the heterogeneity. Data were analyzed using random effects model. Funnel plots and Egger test were applied for assessing publication biases. The hazard ratios (HRs) and 95 % confidence intervals (CIs) were calculated for evaluation of relationship between the polymorphism with HNSCC's prognosis. Results: Fifteen articles were included for the systematic review. Six of those articles were considered for inclusion in meta-analysis. The different forms of XRCC1 Arg399Gln polymorphism had not significant association with overall survival (OS) under varied genetic models (heterozygous: Ln (HR) = 0.02, 95 % CI= (-0.33,0.37), p-value = 0.90; homozygous: Ln (HR) = 0.33, 95 % CI= (-0.03,0.69), p-value = 0.07 and dominant: Ln (HR) = 0.06, 95 % CI = (-0.17,0.28), p-value = 0.62). Analysis showed that variants of the polymorphism had no significant relationship with OS in Asian and Caucasian ethnicity under dominant model (Ln (HR) = 0.14, 95 % CI= (-0.13,0.40), p-value = 0.31; Ln (HR) = -0.01, 95 % CI= (-0.41,0.38), p-value = 0.96). Conclusion: Different forms of XRCC1 Arg399Gln polymorphism had no significant relationship with HNSCC's prognosis under varied genetic models and based on different ethnicity.

The association between high-risk human papillomavirus and oral lichen planus.

OBJECTIVES: Oral lichen planus (OLP) is a cell-mediated inflammatory mucosal disorder and is classified as an oral potentially malignant disorder. Some research has shown that apoptosis in OLP cells is similar to a viral infection such as human papillomavirus (HPV). So, the aim of this case-control study was to investigate the association of high-risk HPV with OLP. MATERIAL AND METHODS: DNA was extracted from 25 formalin-fixed, paraffin-embedded (FFPE) OLP tissues and 25 FFPE normal oral tissues as case and control groups, respectively. The presence of high-risk HPV16 and HPV18 DNA was investigated by polymerase chain reaction (PCR). p-value<.05 was considered significant. RESULTS: Twelve samples (48%) of OLPs were positive for HPV16, compared with six samples (24%) of controls; although the difference was not significant, it was borderline (p = .07). Three samples (12%) of OLPs were positive for HPV18 compared with one sample (4%) of controls; the difference was not significant (p = .3). The total frequency of both high-risk HPV were 14 samples (56%) of OLPs and 7 samples (28%) of controls; there was a significant association between the high-risk HPV and OLP (p = .04). High-risk HPVs was more prevalent in erosive-atrophic (EA) form of OLP as compared to non-EA form, although the difference was not significant (p = .13). CONCLUSIONS: The results suggest a significant association between high-risk HPVs and OLP.

The association between MMP-13 rs478927 gene polymorphism and dental caries susceptibility in children with mixed dentition from Birjand, Iran: A case-control study.

Background and Aims: Gene polymorphisms are responsible for at least part of the variation in caries susceptibility despite similar environmental factors. Genes involved in enamel formation like matrix metalloproteinase-13 (MMP-13) may participate in caries process. The aim was to investigate the association between MMP-13 rs478927 polymorphism and caries susceptibility in 6-years-old children from Birjand, Iran. Methods: Six-years old children from Birjand, Iran, participated in this study. The total decayed, missing, and filled teeth were calculated and defined as caries index (CI). Based on this CI, two groups of high-caries (case) and low-caries (control) were taken into account. Saliva samples were collected and DNA was extracted. The allele and genotypes of MMP-13 rs478927 polymorphism were determined by tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR) method. p Value was significant if p < 0.05. Results: Three hundred sixty-seven children consisted of 186 low-caries children and 181 high-caries children were included in this study. The mean CI was 6.02 ± 0.81. There was no significant association between high and low-caries groups based on socioeconomic status, eating sweet snacks, parents' susceptibility to dental caries, duration of breastfeeding, and the brushing habit (p > 0.05). There wasn't any significant association between genotype distribution of MMP-13 rs478927 polymorphism and CI groups (p = 0.924). This polymorphism was associated with increased caries susceptibility under all genetic models but this effect was not significant (p > 0.05). Conclusion: The MMP-13 rs478927 gene polymorphism was not significantly associated with dental caries susceptibility in Birjandi children with mixed dentition. It is recommended to conduct studies on children of different dentitions to better understand the role of this polymorphism on caries susceptibility in primary and permanent teeth of children.

Mental health status of dentists during COVID-19 pandemic: A systematic review and meta-analysis.

Background: The effect of coronavirus disease-2019 (COVID-19) on the mental health status of dentists has been studied in various studies. The aim of this study was to review the mental health status of dentists during COVID-19 pandemic. Methods: English databases including PubMed, Web of Science and Scopus were systematically searched till July 2021. Studies that examined the mental health status of dentists during COVID-19 pandemic were included. The heterogeneity of articles was assessed with the Cochran Test and I 2 statistics. The prevalence rates of anxiety, fear, sadness, concern, and anger were calculated using the random-effect model. Findings: Of 560 initial searched articles, 15 articles were eligible to include. The prevalence of anxiety, fear of carrying the infection, fear of getting infected, fear of getting quarantined, and fear of dying people by COVID-19 were 64%, 92%, 85%, 61%, and 65%, respectively. The distribution frequency of light, moderate, and intense sadness was 22%, 25%, and 30%, respectively; light, moderate, and intense anger was 21%, 14%, and 23%, respectively; light, moderate, and intense concern was 30%, 30%, and 34%, respectively; light, moderate, and intense fear was 38%, 24%, and 15%, respectively. Conclusion: Fear of COVID-19 and anxiety was very high among dentists. A significant proportion of dentists had moderate to intense COVID-19-associated sadness, concern, and anger. Providing educational content along with providing the necessary personal protective equipment and extensive vaccinations will help maintain the mental health of dentists and provide better quality services.

Primary intracranial peripheral primitive neuroectodermal tumor in an adult patient with aphasia: A rare case report.

Primary intracranial peripheral primitive neuroectodermal tumors (pPNETs) are extremely rare malignancies that commonly affect children and adolescents. Only 10 cases over the age of 33 have been reported. pPNETs have an aggressive behavior and a high tendency for local recurrence and distant metastasis. Here, we present a case of supratentorial pPNET that affected the left frontoparietal lobe of a 36-year-old female patient. The patient complained of aphasia during the last 2 months. Aphasia is reported for the first time as a result of a pPNET. In T1-weighted MRI, a large mass with mixed isointense to hypointense signals was observed. The tumor was completely removed. Histopathologic examination was indicative of a small round cell tumor. Immunohistochemical analysis showed positivity for CD99. Presence of EWSR1 gene rearrangement confirmed the diagnosis. The patient's aphasia was gradually resolved post-surgery. Six months follow-up showed no evidence of local recurrence or metastasis.

Central odontogenic fibroma, hyperplastic dental follicle, or dentigerous cyst? A diagnostic dilemma: A case report.

Central odontogenic fibroma (COF) is an extremely rare benign odontogenic tumor, which is associated with an unerupted tooth in one-third of the cases. Hyperplastic dental follicle (HDF) is an odontogenic hamartomatous lesion associated with delayed or tooth eruption failure in young patients. Dentigerous cyst (DC) is an epithelial-lined developmental cyst surrounding the crown of an unerupted or impacted tooth. Here, we present a case of 13-year-old boy with pericoronal radiolucency around impacted right maxillary canine tooth, which detected during routine dental examination on panoramic radiograph. The size of radiolucency was varied between 5 and 10 mm and was asymmetrical. Lesion was underwent biopsy with suspicion to a dentigerous cyst. On microscopic examination, the lesion was composed of a cellular fibrous connective tissue with odontogenic epithelium in the form of strands or nests throughout the lesion and calcifications in the form of basophilic cementum-like material and dentinoid. Due to its nonspecific histological features, we encountered a diagnostic dilemma. In this case report, we discuss the clinical and radiologic features of COF, DC, and HDF. We preferred COF for this lesion. By combining surgical and orthodontic treatments, the impacted tooth was directed to its correct position in the maxilla. This case report highlights the importance of clinicopathological correlation in the diagnosis of pericoronal radiolucencies.

Adenoid Cystic Carcinoma with Intracranial Extension.

Adenoid cystic carcinoma (ADCC) is a malignant tumor of salivary gland origin. ADCC of sinonasal tract is rare. We present a rare and unresectable case of sinonasal ADCC with intracranial extension in an 83-year-old man with the chief complaint of nasal congestion. Invasion to the maxillary sinus, nasopharynx, anterior cranial fossa, sella turcica and extension to cavernous sinus, dura mater and infratemporal fossa were evident on MRI and CT scan. The patient was treated only by palliative radiotherapy, but unfortunately, he died 3 months after the initial diagnosis.

Head and neck cancer organoids as a promising tool for personalized cancer therapy: A literature review.

Background and Aim: Chemotherapy and targeted therapy are used in treating head and neck cancers (HNCs) either alone or in combination with surgery, especially in advanced tumors but these treatments have resulted in variable outcomes in different patients. This, along with the introduction of new therapies to improve the survival of patients makes it necessary to search for models that can predict the response to treatment among different patients. Organoids, as three-dimensional culture models, have been studied more widely in non-HNCs and to a lesser extent in HNCs as tools to predict treatment outcomes. We aimed to conduct a review to validate the use of organoids as a preclinical tool for the treatment of HNCs patients. Methods: A comprehensive literature search was separately performed by both authors in PubMed and google scholar databases, using the following keywords: "organoid," "head and neck cancer," "personalized medicine," "chemotherapy," and "targeted therapy." The articles published up to September 2021 were included in this review and selected according to a quality appraisal method. Results: Examination of HNC-derived organoids made in various studies showed that these organoids had the ability to recapitulate original tumor features, including histopathological properties, functional characteristics, and expression of molecular markers in almost all of the studies. Differential sensitivity to chemotherapy drugs similar to in vivo was observed in sensitivity testing. Epidermal growth factor receptor (EGFR) expression levels were different between organoids from different patients and EGFR expression level was found to correlate with the response to anti-EGFR targeted therapy. A similar result was reported for organoids derived from salivary adenoid cystic carcinoma. Conclusion: Since HNC-derived organoids seem to recapitulate characteristics of original tumors and to show differential responses to different chemotherapy and targeted therapy agents, these organoids might have the potential to be used as preclinical prediction tools for the treatment of HNC patients.

Angiotensin-converting enzyme 1 and voltage-gated potassium channel-interacting protein 4 gene polymorphisms in COVID-19 patients from east of Iran.

BACKGROUND: Coronavirus disease 2019(COVID-19), the infectious respiratory disease caused by a newly discovered pathogen (severe acute respiratory syndrome coronavirus 2), is a pandemic that places a burden on the health care system. Recently, most research on COVID-19 has emphasized its profound impact on specific regions and ethnic groups. A possible explanation for these variations in disease presentation and severity might be differences in the gene pool of populations. This study therefore attempted to clarify possible involvements of genetic factors affecting COVID-19 pathogenesis with a focus on voltage-gated potassium channel-interacting protein 4 (KCNIP4) and angiotensin-converting enzyme 1 (ACE1) gene polymorphisms. MATERIALS AND METHODS: In this case-control study, the polymorphisms were genotyped using PCR in 194 COVID-19 patients and 194 healthy controls. RESULTS: COVID-19 susceptibility and severity appeared to be unaffected by these polymorphisms. However, this study supported the relevance of ACE1 II genotype frequency to a decreased number of deaths due to the infection. We found that COVID-19 patients with the ACE1 II genotype have a statistically significant better chance of survival (p = 0.008). CONCLUSION: This study strengthens the idea that the ACE1 I/D polymorphism can be a novel prognostic factor indicating the outcome of COVID-19.

Prevalence of corona-associated anxiety and mental health disorder among dentists during the COVID-19 pandemic.

AIM: The aim of this study was to investigate the prevalence and severity of corona-associated anxiety and mental health disorder among Iranian dentists during the COVID-19 pandemic. METHODS: A study was conducted using online survey from May 2nd to 14th, 2020. The questionnaire consisted of three sections: demographic information, anxiety (18 questions), and general health (GH) (GHQ-28). Scoring system was based on Likert scale. The questionnaire was registered at Porsline website. Data were analyzed using t test and Pearson's correlation coefficient statistical tests. RESULTS: A total of 320 dentists from all over the country fully completed questionnaires. 42.5% of dentist had corona-associated anxiety and 32.5% out of them had mild severity and no severe anxiety was observed. 62.5% of dentists were nonpsychiatric according to GHQ-28, 35% had mild disorders in GH, and no one had severe GH disorders. There were significant relationships between gender, marital status, and family history of psychiatric disorders with GH status. There was a significant relationship between history of physical illness with corona-associated anxiety. There was a significant relationship between history of psychiatric disorders with corona-associated anxiety and GH status. CONCLUSION: The prevalence of corona-associated anxiety and mental disorders in dentists was moderate; by holding psychological workshops to maintain and strengthen the morale of dentists during the corona pandemic, along with teaching them the correct way to use personal protective equipment, while maintaining the mental health of dentists, we will help them return to work and provide dental services.

Epidemiological, imaging, laboratory, and clinical characteristics and factors related to mortality in patients with COVID-19: a single-center study.

OBJECTIVE: Coronavirus disease 2019 (COVID-19) is a novel pandemic. Considerable differences in disease severity and the mortality rate have been observed in different parts of the world. The present study investigated the characteristics and outcomes of patients hospitalized with COVID-19 in Iran. METHODS: We established a retrospective cohort to study hospitalized COVID-19 patients in Iran. Epidemiological, imaging, laboratory, and clinical characteristics and outcomes were recorded from medical documents. The chi-square test, t-test, and logistic regression models were used to analyze the data. A p<0.05 was considered to indicate statistical significance. RESULTS: In total, 364 cases (207 males and 157 females) were analyzed. The most common symptoms were cough, fever, and dyspnea. Multifocal bilateral ground-glass opacities with peripheral distribution were the predominant imaging finding. The mean age of patients was 54.28±18.81 years. The mean age of patients who died was 71.50±14.60 years. The mortality rate was 17.6%. The total proportion of patients with a comorbidity was 47.5%, and 84.4% of patients who died had a comorbidity. Sex, history of diabetes mellitus, and dyslipidemia were not significantly associated with mortality (p>0.05). However, mortality showed significant relationships with body mass index; age; history of hypertension, chronic kidney disease (CKD), ischemic heart disease, cerebrovascular accident (CVA), pulmonary disease, and cancer; and abnormal high-resolution computed tomography (HRCT) findings (p<0.05 for all). Cancer had the highest odds ratio. CONCLUSION: Comorbidities (especially cancer, CKD, and CVA), severe obesity, old age, and abnormal HRCT findings affected the health outcomes of patients hospitalized with COVID-19.

Comparison of the frequency of periodontal pathogenic species of diabetics and non-diabetics and its relation to periodontitis severity, glycemic control and body mass index.

OBJECTIVES: To investigate common pathogenic bacteria of periodontal diseases (PD) in patients with type 2 diabetes mellitus (T2DM) and its relationship with PD severity, glycemic control and body mass index (BMI). MATERIAL AND METHODS: This case-control study consisted of 55 patients with T2DM and 55 individuals as control. Samples were collected from periodontal pockets. After DNA extraction, using 16srRNA-specific primers, the presence of Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Prevotella intermedia (Pi), and Fusobacterium nucleatum (Fn) were examined based on polymerase chain reaction method. RESULTS: Aa frequency was significantly higher in in T2DM group than control. There were no significant differences in the frequencies of Pg, Tf, Pi, and Fn between studied groups. There were no significant differences between frequencies of studied bacteria in different severities of periodontitis in T2DM group. Prevalence of Tf in T2DM patients with moderate periodontitis was significantly higher than non-diabetics with moderate periodontitis. There was no significant difference between the frequency of bacteria in diabetics with good and poor glycemic control. There was a significant difference between the frequencies of Pg in T2DM individuals with different BMI levels. CONCLUSIONS: A higher frequency of detection of Aa was found in diabetic when compared to non-diabetics. Glycemic control did not affect the frequency distribution of studied bacteria in T2DM. Pg was identified in higher frequency in overweight T2DM patients.

Comparison of the use of personal protective equipment and infection control in dentists and their assistants before and after the corona crisis.

BACKGROUND: Coronavirus disease 2019 is a new viral outbreak in the world. Dentists and their assistants are at greatest risk of exposure to the virus, due to close contact with patients and dealing with aerosols. Hence, the aim of this study was to compare the use of personal protective equipment (PPE) and supplementary protective equipment (SPE) and observance of the principles of infection control (PIC) in dentists and their assistants before and after the corona crisis. MATERIALS AND METHODS: This cross-sectional study was conducted using an online survey from May 6 to 20, 2020. Convenience sampling was used to select individuals. The questionnaire, consisting of four general categories about the use of PPE and SPE and the observance of PIC by dentists and their assistants before and after corona crisis, was registered at Porsline website (https://survey.porsline.ir/s/KUt7VQB). Frequencies in each subcategory were calculated and comparisons were done using Chi-square test, Fisher's exact test, and paired sample t-test. A P < 0.05 was considered statistically significant. RESULTS: There were significant differences in the frequency of use of PPE by dentists before and after corona crisis for oral and dental examination and also dental procedures (P < 0.001). There were significant differences in the frequency of use of SPE and observance of PIC before and after corona crisis, except for different types of suction types (P = 0.22), dental handpiece (P = 0.66), and dental unit (P = 1). There were significant differences in the frequency of use of PPE by dental assistants before and after corona crisis (P < 0.001). CONCLUSIONS: Although the frequency of use of PPE and observance of PIC increased among dentists and their assistants, this increase is not sufficient, especially for dental assistants, and a higher level of use of PPE and PIC observance in face of highly contagious and life-threatening viruses such as corona is required.