فهرست مطالب mohsen dalband

The coronavirus disease 2019 (Covid-19) has become a public health emergency of worldwide concern. In addition to the serious impacts of this disease, it has caused numerous problems for dental treatments. Here, the findings on the first phase of the cohort study on reopening the School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran and its subordinate clinics during the COVID-19 pandemic were reported. Data were collected via a 100-item self-administered online questionnaire from June 2 to June 20, 2020. A total of 1,110 members from the academics, students, and personnel of the school participated in the study. The questionnaire included demographic data, socio-personal patterns, systemic conditions, COVID-19 infection information, and personal protective equipment (PPE). Since the outbreak of the pandemic, 87.4% of the professors, 49.0% of the students, and 29.0% of the personnel of the school used personal vehicles other than public transportation. In addition, over 50.0% of the students and about 70.0% of the other two groups had not attended any gatherings. Moreover, 83.0% of the academics, 93.0% of the students, and 84.0% of the personnel had no systemic conditions. Furthermore, about 16.0% of the professors, 14.0% of the students, and 22.0% of the personnel had tested for the COVID-19 infection, of whom only about 1.0% reported positive results. Fatigue, dry coughs, and shortness of breath were the most common symptoms reported by the respondents. Dental offices are high-risk environments for the transmission of air-borne diseases. Considering the low percentage of the participants with positive test, it may be concluded that the safety protocols could effectively limit the spread of the COVID-19 infection.

Mental health problems can negatively affect one’s ability to take precautionary measures. The aim of this study was to evaluate the effects of perceived stress and self-care behaviors on precautionary measures against COVID-19 among staff and students in shahid Beheshti Dental School.

This cross-sectional study was conducted after reopening of the school. Information was collected from 830 people (academic members, students, and staff) within two weeks in spring 2020. A questionnaire was designed consisting of items on demographic characteristics, perceived stress, self-care behaviors, and precautionary measures. To calculate the coefficients of the effects of stress and self-care behaviors on precautionary measures, path model analysis was applied.

There was a significant relationship between perceived stress and precautionary measures in dental students. In this group, stress had a significant direct effect on preventive social behaviors (P<0.001). On the other hand, the negative effects of perceived stress on both individual and social preventive measures were mediated via self-care measures. In academic members, perceived stress was not found to significantly affect precautionary measures (P=.28). In staff, self-care behaviors had significant positive effects on both individual and social preventive measures (P<.001).

Perceived stress as an exogenous variable had both direct and indirect effects on social preventive behaviors. It also affected individual preventive behaviors via self-care measures as an endogenous variable.

COVID-19 virus has spread like a pandemic from the beginning of 2020 and has caused many dangers and concerns. The virus is commonly transmitted through the respiratory tract and infected aerosols, the production of these aerosols during dental treatment increases the risk of infection among staff and patients. The present study investigates the prevalence of the COVID-19 virus in patients referred to Shahid Beheshti Dental School.For 3 months duration.

This descriptive and cross-sectional study was performed on 193 patients after the reopening of the dental clinic during the outbreak of COVID-19 from June to September 2020 in Tehran. Patients were asked questions about their general health status and condition when visiting the faculty by telephone interview and the data were recorded.

About 17% of patients had a systemic disease and about 60% of them had regular vitamin D intake. Most blood groups belonged to groups O and A. A small number of patients (6.20%) reported having corona virus-infected individuals in their family members. About 8% of patients also reported having corona disease but were unsure of the cause. Patientschr('39') satisfaction with health behaviors and personal protection of the faculty was high (99%).

The results of this study indicate the prevalence of factors affecting the incidence and severity of Covid-19 disease among patients referred to the clinic of the faculty of dentistry. Given the uncertainties surrounding the nature of the virus, it is not possible to provide fully effective protection protocols; however, adhering to protective protocols can reduce the spread of the disease.

Mental health is an inseparable part of overall health and healthcare workers have experienced mental issues during the COVID-19 pandemic. This study aimed to investigate the amount of stress undergone by dental students and its affecting factors.

This cross-sectional study included all students of Shahid Beheshti Dental School, Tehran. The data on demographic and individual-social characteristics of the participants and questions related to the perceived stress level (PSS-10 questionnaire) were collected using an online questionnaire. The results were analyzed using a T-test and the correlations in SPSS-26 (P<0.05).

A total of 511 students participated in the study. The mean score of the perceived stress level was 15.9 out of 40, indicating a moderate level of perceived stress. Eleven students had suffered from COVID-19 and 13% were in close contact with those infected. Most of the students (72%) used public transportation. About 60% regularly did exercise, and the majority had enough hours of sleep. After examining the relationship between the individual factors and perceived stress level, it was revealed that the PSS was significantly lower in people who had adequate and a regular sleeping timetable (p<0.05). Furthermore, people who had contracted the COVID-19 virus (p=0.019) or had relatives who were infected (p =0.007) experienced higher levels of stress. Suffering from preexisting medical conditions was another significant factor in higher perceived stress levels (p=0.027).

This study indicated that students had gone through a moderate level of stress during the COVID-19 pandemic. People with systemic conditions, sleep disorders, and those who had contracted the COVID-19 virus themselves or their reletives, experienced higher levels of stress. The requirement to provide courses on stress management skills, family awareness, and use of mental health services to reduce the negative effects of this psychological burden is highly recommended .

The advent of Severe Acute Respiratory Syndrome Coronavirus 2 (so-called SARS-CoV-2) causing Coronavirus Disease 2019 (so-called COVID-19) occurred in Dec. 2019 in Wuhan, China. Having an inconceivable worldwide contagion, the outbreak was labeled a pandemic by the WHO. Dental services and related professions (including dentists, dental assistants, dental hygienists and the personnel of cleansing, remedial, triage, dental laboratories, radiographic laboratories and other related paraclinicals), facing galore aerosol and droplets, are in the topmost risk groups exposed to the queer virus. This study was fulfilled to round up evidence-based data to break a link at any part of the virus transmission chain in dental services and related professions.

Relevant online databases, as PubMed, MEDLINE, Embase, Scopus, Google Scholar and TripDatabase were searched meticulously and evaluated for relevant published original research papers. Subsequently, to fulfill the investigation, ADA, CDC and WHO websites were reviewed to gain relevant guidelines and protocols. Consequently, 476 resources were included considering the canonical inclusion criteria. For the sake of quality assessment of the resources, an authentic checklist was exploited to score the resources from 1 to 15, wherein the admissible score was 10. After deliberation of resources, 366 of them were excluded and finally, 110 resources were selected and overhauled to attain a comprehensive perception on the subject of the investigation.

Transmission of SARS-CoV-2 includes direct transmission (via droplet and aerosol inhalation) and indirect transmission (via surface and instrument contamination), which can amply occur in dental services and related professions. Therefore, an all-inclusive evidence-based miscellany was rallied on several exigent topics, containing genuine esteem in reputable scientific authorities, to present a consummate report for the dental clinicians and related practitioners, working in the course of the running pandemic.

Contemplating the ongoing crisis, undertaking a set of miscellany elected guidelines and protocols, is indispensable in this vital interval of history to bridle the current pandemic, which has been abridged via this systematic perusal.

Many studies have been performed on the effect of low level laser on wound healing which has been associated with different and sometimes contradictory results. On the other hand, considering that stress may affect the immune system the fact that it may delay wound healing has also been addressed. Therefore, the present study aimed to investigate the simultane- ous effect of low level laser therapy and stress on wound healing at the three levels of histology (histological changes), biomechanics (stress and strain assessment) and macroscopic (wound size).

In this interventional study, 72 male Wistar rats (8-10 weeks old, weight range: 240 to 330g) were randomly divided into three treatment groups and one control group. (18 per group). In all the rats, a 2.5cm full-thickness skin incision was made on the dorsal spine. Intervention was performed from day 1 to day 21 every other day with Kals-DX61 laser (cap s) with wavelength: 660nm, dose 3J/cm2 , 100 sec and power density 30mW/cm2 . Then, wound size was measured weekly until the third week (day 21). Then, tension metric tests were performed to evaluate the stress and strain of the restored tissue. At the end of each week, three animals from each group were sacrificed for histopathological evaluation.

There was a significant difference between the stress/no laser and laser/no stress groups in all stages of evaluation. Mean and standard deviation of stress and strain were not significantly different in the study groups.

Stress can potentially slow the wound healing process, while receiving low level laser therapy speeds up the wound healing process, although in the end there was no significant difference in biomechanical characteristics between the groups.

 Antibiotics are routinely administered in clinical setting for prevention of infections in surgeries and as a routine supplement to the culture medium. The nobility of the present study was to evaluate the effect of two commonly used antibiotics, clindamycin and cefazolin, in dental treatments, on osteogenic capability of periodontal ligament stem cells (PDLSCs). 

 PDLSCs were isolated from periodontal ligament (PDL) of the root section out of four healthy extracted teeth. The cells were incubated in the following medium for 28 days: (1) Osteogenic medium (OM) + 5 µm clindamycin (clindamycin group), (2) OM + 5 µm cefazolin (cefazolin group) and (3) OM (control group). Alizarin red staining was performed at days 7, 14, 21, and 28 of induction. 

 Addition of cefazolin to osteogenic medium had no significant effect on osteogenesis comparing to the control group. However, Clindamycin significantly inhibited osteogenesis at days 7 and 21 comparing to the control group (P<0.05), but there was no significant differences at 14 and 28 days. 

 It is demonstrated that clindamycin had inhibitory effects on osteogenesis in early stages, but it promoted osteogenesis in later stages. Cefazolin seems not inhibit osteogenic potential of the cells. Taken together, prescribing cefazolin or clindamycin did not cause any negative effect on osteogenesis for long-term.

Craniofacial skeletal metastasis is a rare presentation of advanced prostate cancer. This is a report of a 69-year-old man who presented with numbness of the right lower lip and recently ill-fitting lower denture. Based on the medical history of benign prostate hyperplasia (BPH) and suspicion of a metastatic tumor, prostate core needle biopsy was performed. Histology of the prostate biopsy confirmed an adenocarcinoma with Gleason Score of 6/10. The diagnosis of metastatic prostate adenocarcinoma was established by incisional biopsy from the mandibular lesion. Androgen deprivation therapy (ADT) was administered along with bilateral orchidectomy and radiotherapy. He had a significant resolution of trigeminal nerve palsy and the other symptoms at subsequent follow-ups, but after 18 months passed away. The second case was a 65-year-old man with a history of prostate cancer since 5 years ago. He complained of painful swelling in the right side of the face. Radiographic evaluation revealed new bone formation in right mandibular ramus and condylar process as well as the left temporoparietal region. Incisional biopsy from mandibular lesion revealed metastatic prostate adenocarcinoma. Palliative radiotherapy for increasing quality of life started for the patient but he died after 9 months. The related literatures were reviewed.

The orthokeratinized odontogenic cyst (OOC) is an uncommon developmental cyst that occurs between the second to fifth decades, more commonly in males. It is a solitary lesion that mostly occurs in the mandible rather than the maxilla. Histologic features include a thin, uniform epithelial lining with orthokeratinization and a prominent granular layer below a non-corrugated onion-skin-like surface.
A 40-year-old man presented with pain and swelling in the left mandibular canine molar area. The panoramic radiograph revealed a well-defined radiolucency extending from the left mandibular canine to the left mandibular molar, with scalloped projections between the teeth roots. Microscopic examination showed a cystic lesion lined by an orthokeratinized stratified squamous epithelium, and a prominent granular layer beneath the cornified layer was seen. The features were those of an OCC.
From the demographic and radiographic perspectives, the features of OOCs can be similar, but more variation can be found on routine histopathological analyses.

The aim of this study was to investigate the displacement and stress distribution during surgically assisted rapid maxillary expansion under different surgical conditions with tooth- and bone-borne devices. Three-dimensional (3D) finite element model of a maxilla was constructed and an expansion force of 100 N was applied to the left and right molars and premolars with tooth-borne devices and the left and right of mid-palatal sutures at the first molar level with bone-borne devices. Five CAD models were simulated as follows and surgical procedures were used: G1: control group (without surgery); G2: Le Fort I osteotomy; G3: Le Fort I osteotomy and para-median osteotomy; G4: Le Fort I osteotomy and pterygomaxillary separation; and G5: Le Fort I osteotomy, para-median osteotomy, and pterygomaxillary separation. Maxillary displacement showed a gradual increase from group 1 to group 5 in all three planes of space, indicating that Le Fort I osteotomy combined with para-median osteotomy and pterygomaxillary separation produced the greatest displacement of the maxilla with both bone- and tooth-borne devices. Surgical relief and bone-borne devices resulted in significantly reduced stress on anchored teeth. Combination of Le Fort I and para-median osteotomy with pterygomaxillary separation seems to be an effective procedure for increasing maxillary expansion, and excessive stress side effects are lowered around the anchored teeth with the use of bone-borne devices.

Surveys of students’ and faculty members’ opinion on the faculties teaching can reveal the strengths and weaknesses of their teaching performance. This study aimed to compare self-evaluation and students’ evaluation about educational performance of Hamadan dental school faculty members in 2010-2011.

In this cross-sectional descriptive and analytical study, through using census sampling method, all 46 faculty members and 77 students of Dental School in Hamadan University of Medical Sciences participated. The data were gathered by two parallel, five- point Likert scale questionnaires each consisting of 18 question items. Data were analysed through Pearson correlation coefficient, paired t-test, ANOVA, and Wilcoxon tests.

The mean of the faculty member's self-evaluation score was 76.02± 10.5 and the mean of this evaluation by students was 71.12± 9.03 which demonstrated a significant difference (p=0.041). The correlation coefficient between the scores of self-evaluation and evaluation by students was -0.299.

Faculty members’ self- evaluation scores were higher than those of the students. Faculty members should pay more attention to the results of this study and improve their teaching performance in order to achieve higher quality educational levels

This clinical report describes a case of maxillary dental rehabilitation using five implants placed simultaneously in three cortico-cancellous iliac bone blocks and rigidly fixed to the residual bone with titanium mini-screws 2-mm in diameter and mini-plates. All “empty spaces” between the bone segments were filled with iliac bone chips harvested from the diploe of iliac bone mixed by Bio-oss. The second surgery was performed 5 months later, when all five implants were integrated, and one cover screw was exposed to oral cavity. Two months after the second surgery, abutments were connected to the implants and loaded with a fixed partial denture.

Orthognathic surgeries are performed for cosmetic and medical reasons. The basic changes in orthognathic surgeries are done over skeletal and tooth sections and hard tissue movements are accompanied with soft tissue changes. Furthermore, the patients’ response to the surgery and imitation of soft tissues from skeletal and teeth movements are very important. Therefore, this study was carried out in order to evaluate soft tissue changes in patients went under orthognathic surgery using profile photographs at Taleghani General Hospital in 1999. Methods & Materials: The study was a quasi - experimental one, using observation as its technique. Profile photographs in natural head position (NHP) were used. Three lines (true horizontal line, constructed vertical line, and tragocontal line) were selected and soft tissue landmarks changes’ were analyzed, considering true horizontal line and constructing vertical line. Photographs were taken before the surgeries and six months after IMF opening. The hard tissue changes were calculated with reference to cephalometric analysis provided before the surgeries and six months after IMF opening. Eight soft tissue landmarks and five hard tissue landmarks were used in this study. The study showed spontaneous hard and soft tissue changes during orthognathic surgery, while there was significant statistical correlation between soft and hard tissue changes. 1- Soft tissue changes are followed by hard tissue changes. 2- Considering age, sex, race, and medical history of the patients are very important before orthognathic surgery.