In Vitro Evaluation of marginal adaptation of polyether ether ketone and zirconia copings.

Background: Polyether ether ketone (PEEK) has emerged as a new thermoplastic material with potential applications as a restorative material. Aim: This study aimed to evaluate the marginal adaptation of PEEK copings compared to zirconia copings using field emission scanning electron microscopy. Materials and Methods: A freshly extracted maxillary central incisor was prepared for a full-coverage restoration following standard principles of tooth preparation. The tooth was sent to a laboratory for fabrication of samples using computer-aided design and manufacturing (CAD/CAM). Twenty samples of polyether ether ketone (PEEK) copings (group A) and 20 of zirconia copings were fabricated (group B). The copings were scanned under a field emission scanning electron microscope and measurements were taken at four distinct points. The marginal adaptation over the buccal, lingual, mesial, and distal margins for both groups was evaluated. One-way analysis of variance (ANOVA) and independent t test were applied. Results: Our findings indicate that PEEK showed better marginal adaptation than zirconia at all measurement points. The mean marginal gap value of the PEEK group was 33.99 ± 8.81 µm and of the zirconia group was 56.21 ± 15.07 µm. On comparing marginal adaptation among the mesial, distal, buccal, and lingual aspects, PEEK showed better adaptation on all four margins, with the best adaptation on the buccal margin that had the lowest mean gap value of 29.27 ± 6.07 µm. The zirconia group adapted best at the distal margin, with a lowest mean gap value of 53.58 ± 15.25 µm (P ≤ 0.05). Conclusion: PEEK copings had better marginal adaptation and fit compared to zirconia copings. It may have applications as a restorative material in fixed prostheses.

Cellulitis in Hajj Pilgrims: Role of Environmental Temperature and Population Size of Pilgrims as a Contributory Factor.

Background Cellulitis is a common infection of the skin and subcutaneous tissue. Meteorological and environmental temperatures were previously identified as potential risk factors for causation and the patient's odds of hospitalization. In this regard, we aim to study the pattern of cellulitis during 10 Hajj seasons and examine the impact of changing seasonal temperatures and overall pilgrim populations as potential risk factors. Methodology In-hospital cellulitis was studied within the context of the Hajj. A retrospective review of pilgrim patients coded for cellulitis was undertaken for the Hajj seasons between 2004 and 2012. Possible roles of environmental temperatures, pilgrim population sizes, and ethnicity were examined as potential risk factors. Results A total of 381 patients belonging to 42 nationalities were identified, with 285 (75%) males and 96 (25%) females with a mean age of 63 years. On average, cellulitis accounted for 23.5% of general surgical admissions with proportional increases from 2004 to 2012 (r= 0.73, p= 0.016), which significantly correlated with the rise in seasonal temperatures (r = 0.7, p= 0.023). Conclusions The findings of this study identified cellulitis as a significant health risk during the Hajj, which is likely to be prevalent in warmer seasons. Our results may assist clinicians in educating Hajj pilgrims of different nationalities about the increased risk of cellulitis during warm seasons and possible predisposing environmental factors of infection.

Suppression of Tumorigenicity 2 Pro-Inflammatory Biomarker Linking Diabetes Mellitus and Periodontitis: A Pilot Study.

BACKGROUND Suppression of tumorigenicity 2 (ST2) is a member of the interleukin (IL)-1 family and has 2 isoforms: ST2L, a transmembrane form, and ST2, a soluble form. IL-33 can act as an immune system alarm signal when released by damaged cells, which in turn activates other cells expressing the ST2 receptor. This can cause inflammatory cytokines to be released and produced, as well as trigger osteoclastogenesis. This study aimed to investigate the levels of soluble ST2 in gingival samples. MATERIAL AND METHODS The study population consisted of 30 individuals. The participants were divided into 3 groups: healthy participants, patients with periodontitis, and patients with periodontitis and diabetes mellitus. Periodontitis was determined using probing depth, clinical attachment loss, and gingival index. Patients with stage 2 to 4 periodontitis met the inclusion criteria. Gingival crevicular fluid (GCF) was collected for quantification of samples for ST2 levels by using an enzyme immunoassay. RESULTS The mean±standard deviation of ST2 GCF concentrations was relatively high (558.87±68.99) in the group with periodontitis and diabetes mellitus, compared with that of the periodontitis group (452.06±54.18) and healthy group (252.82±87.9). CONCLUSIONS GCF ST2 values were found to be a marker of inflammatory activities. Thus, GCF ST2 could be a potential biomarker for the diagnosis of periodontitis as well as systemic diseases, such as diabetes mellitus. This pilot study was limited by a small number of participants. To confirm the associations, more large-scale investigations should be conducted.

Role of Toothbrushes as Gene Expression Profiling Tool for Oral Cancer Screening in Tobacco and Alcohol Users.

AIM: The use of toothbrushes was investigated as a potential RNA source and gene expression profiling tool for oral cancer screening in tobacco and alcohol users. METHODOLOGY: A total of 20 subjects were selected on the basis of inclusion and exclusion criteria. They were divided into two groups: group I-healthy controls (n = 6); group II-individuals who consume tobacco and alcohol (n = 14). After the volunteers brushed their teeth using a soft-bristle toothbrush with ~0.5 gm of toothpaste, the toothbrushes were collected, and the gene expression of BAX, BCL2, CDK4, CKDN2A, GNB3, and TCF7L2 was assessed. RESULTS: The gene expression of BAX decreased significantly in alcoholics and smokers (0.13867 ± 0.12014), while the gene expression of BCL2 increased in alcoholics and smokers (1.91001 ± 0.90425) in comparison with healthy controls (p = 0.0054 and p = 0.0055). Although there was increased expression of CDK4, CKDN2A, and TCF7L2 and decreased expression of GNB3 in smokers and alcoholics, the results were not significant. CONCLUSIONS: A toothbrush is a good source of RNA, and gene expression analysis can be performed using the genetic material retrieved from toothbrushes, which can aid in the early diagnosis of oral squamous cell carcinoma among tobacco and alcohol users. Further studies with a larger sample size and different durations of toothbrush use should be conducted to explore the role of toothbrushes as a noninvasive tool for disease diagnosis.

Evaluation and Comparison of Genomic DNA Extraction Methods and PCR Optimization on Archival Formalin-Fixed and Paraffin-Embedded Tissues of Oral Squamous Cell Carcinoma.

Recovery and amplification of nucleic acids from archived formalin-fixed tissue samples is the most developing field in retrospective genetic studies. We compared different deparaffinization methods and DNA isolation techniques, and intergroup comparisons were performed to evaluate the effectiveness of different storing methods for archival OSCC samples based on obtained mean DNA quantity, quality, and PCR amplification of the P53 gene. The study comprised 75 archival histologically diagnosed OSCC samples which were divided into Group I: Formalin-fixed paraffin-embedded tissue blocks and Group II: Long-term formalin-fixed tissue. A comparison of different deparaffinization methods showed that xylene deparaffinization is an efficient method to obtain suitable DNA. Comparing different DNA isolation techniques illustrated that the conventional phenol-chloroform method gives better integrity to DNA in contrast with the kit method. Comparison between FFPET and long-term FFT samples demonstrated that samples fixed in formalin overnight and embedded in wax yield better quality and quantity DNA in comparison with long-term samples fixed in formalin. To obtain suitable integrity of DNA, tissue samples should be stored by fixing in formalin overnight followed by preparation of paraffin tissue blocks, deparaffinization by xylene, and subjecting them to the conventional phenol-chloroform DNA isolation protocol.

Initial outcomes of one anastomosis gastric bypass at a single institution.

INTRODUCTION: One anastomosis gastric bypass (OAGB) is an emerging bariatric procedure, which has been reported to be safe and effective. This study aims to evaluate the short-term outcome of OAGB and its midterm effects on weight loss and remission of type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: A retrospective review of patients who had undergone OAGB between January 2013 and January 2017 in King Abdulaziz University Hospital, Jeddah, Saudi Arabia, is presented here. Patients' perioperative characteristics, biochemical profile (fasting blood glucose, HbA1c and iron profile) and details on subsequent weight loss in terms of body mass index (BMI) and excess weight loss percentage (EWL%) along with early and late postoperative complications were evaluated. RESULTS: Out of the 47 patients who underwent OAGB, 42 were included in this study and completed the 2-year follow-up. Average operative time was 107±21.3 minutes and average length of hospital stay was 2.5±0.53 days. Mean preoperative BMI was 47.6±9.1 kg/m2, and at 1 and 2 years of follow-up, it was 30.5±7.4 and 27.1±5.1, respectively. No mortality, anastomotic leak or bleeding were reported. Most common midterm complication was iron deficiency anemia (n=7/42). Remission of T2DM at 6 months was 80%. Patients with preoperative T2DM for less than 10 years showed better remission (P<0.001). CONCLUSION: Our analysis suggests that OAGB is a safe and effective weight loss procedure that carries low perioperative risk and acceptable nutritional complications in the midterm, with a notable remission of T2DM. Preoperative duration of T2DM plays a major role in achieving remission after OAGB.

VWC2 Increases Bone Formation Through Inhibiting Activin Signaling.

By a bioinformatics approach, we have identified a novel cysteine knot protein member, VWC2 (von Willebrand factor C domain containing 2) previously known as Brorin. Since Brorin has been proposed to function as a bone morphogenetic protein (BMP) antagonist, we investigated the binding of Brorin/VWC2 to several BMPs; however, none of the BMPs tested were bound to VWC2. Instead, the ßA subunit of activin was found as a binding partner among transforming growth factor (TGF)-ß superfamily members. Here, we show that Vwc2 gene expression is temporally upregulated early in osteoblast differentiation, VWC2 protein is present in bone matrix, and localized at osteoblasts/osteocytes. Activin A-induced Smad2 phosphorylation was inhibited in the presence of exogenous VWC2 in MC3T3-E1 osteoblast cell line and primary osteoblasts. The effect of VWC2 on ex vivo cranial bone organ cultures treated with activin A was investigated, and bone morphometric parameters decreased by activin A were restored with VWC2. When we further investigated the biological mechanism how VWC2 inhibited the effects of activin A on bone formation, we found that the effects of activin A on osteoblast cell growth, differentiation, and mineralization were reversed by VWC2. Taken together, a novel secretory protein, VWC2 promotes bone formation by inhibiting Activin-Smad2 signaling pathway.

Expression of Evc2 in craniofacial tissues and craniofacial bone defects in Evc2 knockout mouse.

OBJECTIVE: Our objectives were to determine the expression of EVC2 in craniofacial tissues and investigate the effect of Evc2 deficiency on craniofacial bones using Evc2 knockout (KO) mouse model. DESIGN: Evc2 KO mice were generated by introducing a premature stop codon followed by the Internal Ribosomal Entry Site fused to ß-galactosidase (LacZ). Samples from wild-type (WT), heterozygous (Het) and homozygous Evc2 KO mice were prepared. LacZ staining and immunohistochemistry (IHC) with anti-ß-galactosidase, anti-EVC2 and anti-SOX9 antibodies were performed. The craniofacial bones were stained with alcian blue and alizarin red. RESULTS: The LacZ activity in KO was mainly observed in the anterior parts of viscerocranium. The Evc2-expressing cells were identified in many cartilageous regions by IHC with anti-ß-galactosidase antibody in KO and Het embryos. The endogenous EVC2 protein was observed in these areas in WT embryos. Double labeling with anti-SOX9 antibody showed that these cells were mainly chondrocytes. At adult stages, the expression of EVC2 was found in chondrocytes of nasal bones and spheno-occipital synchondrosis, and osteocytes and endothelial-like cells of the premaxilla and mandible. The skeletal double staining demonstrated that craniofacial bones, where the expression of EVC2 was observed, in KO had the morphological defects as compared to WT. CONCLUSION: To our knowledge, our study was the first to identify the types of Evc2-expressing cells in craniofacial tissues. Consistent with the expression pattern, abnormal craniofacial bone morphology was found in the Evc2 KO mice, suggesting that EVC2 may be important during craniofacial growth and development.