Statement of problem In the outbreak of Covid-19, coinfections and even superinfections in the background of SARS-CoV-2 viral infection have been reported. Such bacterial and fungal strains may be colonized in different tissues and organs, including the oral cavity. Whether infection with Covid-19 could increase colonization of different bacterial strains on removable dental prostheses is unclear. Purpose The purpose of this clinical study was to compare bacterial colonization on removable dental prostheses in patients with Covid-19. Material and methods Two sex- and age-matched groups of complete-denture wearing participants (N=60) with and without a positive diagnosis for Covid-19 were enrolled in the study. Swabs were used at 2 different time intervals to sample areas of the dentures, which were then cultured and the colony smears Gram stained. Statistical analysis was conducted by using the Mann U Whitney test (α=.05). Results Streptococcus species (93.3% versus 40.0%, P =.047) and Klebsiella pneumonia (46.7% versus 13.4%, P =.036) were detected more frequently in the Covid-19 positive group. Conclusions Higher rates of bacterial colonization, especially with Streptococcus species and Klebsiella pneumonia, were detected on removable dental prostheses after Covid-19 infection.

Chronic lymphocytic leukemia (CLL) is one of the most common hematologic neoplasms leading to immunosuppression. It is characterized by absolute lymphocytosis with clonality of mature B cells. Therefore, they are vulnerable to various infections especially COVID-19. Little is known about the COVID-19 infection when it unmasks CLL.We reported a 90-year-old man who presented with signs and symptoms of anorexia, weakness, and loss of consciousness, and lymphocytosis which in further workup COVID-19 confirmed with real-time PCR. Due to lymphocytosis, peripheral blood smear (PBS) and flow cytometry were performed and CLL was diagnosed. His lymphocyte count increased to 1.5-fold during hospitalization.The patient recovered after 11 days as the symptoms were alleviated.Lymphocytosis is an unexpected finding in patients diagnosed with COVID-19 infection, and an increase in lymphocytes may indicate other conditions. In these cases, secondary causes of lymphocytosis, such as malignancy or other infections, should be considered

Objectives: Unclassified gingival papules might be mistaken with other malignant lesions as they resemble some other oral lesions. The present study demonstrates epidemiologic and histopathological characteristics of the gingival unclassified papules in the patients referred to Urmia Dental School, Iran. Materials and Methods: A cross sectional descriptive study design was conducted among 500 pateints in Urmai university of medical sciences, Iran. The participant's demographic data and medical history were obtained using clinical examinations and a questionnaire. Histopathological assessments were done in two specimens. The effect of the possible factors on the incidence of gingival papules was statistically assessed by Fisher's exact test. Results: Among 500 participants, 340 (68%) demonstrated unclassified gingival papules (40.9% males, 59.1% females; mean age of 34.9 years). No significant differences were found regarding the effect of gender, smoking, mouth breathing, history of skin disease or pregnancy on the incidence of gingival papules. However, the breastfeeding females ( P < 0.004) or those using contraceptive pills ( P < 0.02) showed lower frequency of papules' incidence. Among 340 papules, 332 (97.6%) were white in color, 337 (99.1%) were well defined and 331 (97.3%) were observed in the keratinized gingiva. 207 (60.9%) were multiple and 133 (39.1%) were single lesions. The papules showed healthy tissues similar to gingival tissue; however, abundant collagen bundles were irregular and close to the surface, which was covering by stratified squamous epithelium. Conclusion: Gingival papules are common findings in patients referring to Urmia Dental School; the lesions were almost white in color, well defined and appeared in the keratinized gingiva. The lesions were a variation of normal oral structures with no treatment requirements.

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Background: One of the effective factors in successful orthodontic treatment is the use of appropriate bond between the orthodontic bracket and surface of the composite restoration. The aim of this study was to evaluate the effect of using composite primers, silane, and surface roughening on the shear bond strength of metal brackets bonded to old composites. Methods: In this laboratory study, 90 composite disks (Z350 3M) measuring 4 by 6 mm were kept in distilled water for 1 week and subjected to 5000°C heating rotation (rpm). These samples were divided into 6 groups based on the use of composite primer, surface roughening, and silane as follows: Group 1 (Control): old composite+37 % acid etching, Group 2: Old composite+37% acid etching+20 s cure. Group 3: Old composite+37% acid etching+5 s air-drying, Group 4: Old composite+acid etching+rubbing, Group 5: Old composite+roughing with diamond bur, Group 6: Old composite+Acid etching+roughing with diamond bur metal brackets were attached to the specimens and the specimens were immersed in water and in a thermal rotation system of 5000 rpm for 1 week. The shear bond strength of the brackets was measured. Results: The highest and the lowest shear bond strength values were found in the fourth and control groups, respectively, indicating a significant difference across all groups (P=0.001). In this regard, the results of least significant difference (LSD) test also showed that the mean shear bond strength of orthodontic brackets in the control group was significantly lower than that observed in other experimental groups, but without significant difference across the pointed groups. Conclusions: The use of surface roughness, composite primer, and silane together do not have a cumulative effect on the increase of the bond strength between old composite and orthodontic brackets. However, the use of each alone can increase the shear bond strength.