An In Vitro Evaluation of a Novel Design Z Plate for Fixation of Mandibular Symphysis and Parasymphysis Fractures-A Finite Element Analysis.

Aim: Surgical management of mandibular symphysis and parasymphysis fractures has evolved from rigid fixation to semi-rigid fixation with miniplate osteosynthesis. Various miniplate systems have been developed in recent years including three-dimensional miniplate, microplates and bioresorbable plate, and their advantages and disadvantages have been compared and studied. To overcome the shortcomings of 3D plating system such as difficulty in adaptation and fixation in fractures involving the mental nerve, a novel Z plate has been designed by our institute. Material and Methodology: An in vitro study was performed to evaluate the biomechanical behaviour of the newly designed Z plate with 3D plate and two-miniplate system using finite element analysis. Results: Our study showed total structural deformation of 0.17 mm and 0.31 mm of newly designed Z plate after canine loading and molar loading, respectively. The equivalent von Mises force for plate after canine loading had shown the following results-Z plate showed values of 121.3 MPa and 58.40 MPa after molar loading. Conclusion: Our study concluded that the Z plate produces lowest stresses, lesser total structural deformation, superior stability and support in comparison with the 3D plate and two-miniplate system.

Survival of Dental Implants on Irradiated Jaws: A Systematic Review and Meta-analysis.

Objectives: Dental implants play a significant role in functional rehabilitation of the oral cavity after debilitating jaw surgeries for oral cavity cancers followed by radiotherapy. Design: The meta-analysis was done using Preferred Reporting Items for Systematic Review (PRISMA) guidelines published from January 1947 till August 2020. Twenty three articles consisting of 1246 participants with 4838 implants were included in our analysis. Results: The mean age of the included participants was 51.4 years. 2186 and 1685 implants were placed on irradiated and non-irradiated jaws and showed a success rate of 82.47% and 89.37% respectively. Correspondingly, publication bias of p value = 0.2129 and p-value = 0.6525 was found by Egger's and Begg's test respectively for pooled data of 16 studies. The implant success rate of 70.4% on maxillary bone and 94.5% were observed on mandibular bone. Timing of implant placement and its influence on survival rate have resulted in a 75.5% survival rate of dental implants when placed primarily in comparison with 87.7% on delayed placement. The waiting interval of 14 months in delayed implant placement has shown better results. Conclusion: Presence of radiotherapy does not play a significant role in the success rate of dental implants in oral cavity cancers. However, delayed implant placement may have a better chance of survival. Supplementary Information: The online version contains supplementary material available at 10.1007/s12663-022-01686-6.

Toward developing natural histologic stains using anthocyanins: A novel approach.

INTRODUCTION: In the present-day scenario, wherein histotechnological laboratory personnel come into contact with numerous hazardous chemicals every day, laboratories are emphasizing on development of safer and environment-friendly alternatives globally which are easily available and feasible. In this context, we have attempted to utilize anthocyanins, a family of pigments naturally occurring in fruits and flowers and which are already used as natural food colorants, for assessing their utility as histological stains. MATERIALS AND METHODS: Juices of thin consistency from well-ripened pomegranates were obtained by using a juicer with blender functions. Formalin-fixed paraffin-embedded 4 µm thin sections were immersed in this solution for 2 h, during which the solution was periodically monitored. Several modifications were attempted such as the addition of Citrus limon (lemon) extract or acetic acid, change in orientation of the slides and refrigeration of the solution during the staining procedure. RESULTS: A peculiar pattern of reasonably diagnostic staining was observed in which the basal and suprabasal cells, basement membrane, inflammatory cells and collagen fibers stained prominently with a magenta color. The addition of lemon, horizontal orientation of slides and refrigeration each separately led to an improvement in staining characteristics. The addition of 4% acetic acid and refrigeration of the solution each led to an improvement in longevity of the staining solution. CONCLUSION: Anthocyanins could potentially be used as viable histological stains having advantages of availability, feasibility, color stability and nontoxicity, although numerous modifications to improve longevity of staining solution and staining characteristics are warranted by further research for which the present study could serve as a pretext.

Expression of mucin-1 in oral squamous cell carcinoma and normal oral mucosa: An immunohistochemical study.

BACKGROUND: Mucins are high-molecular-weight glycoproteins with a high O-linked carbohydrate content, which are synthesized by many secretory epithelial cells as membrane-bound and/or secreted products. Mucin-1 (MUC1) is a transmembrane mucin that protects and lubricates the mucous membranes of the human body and involves itself in various cellular functions such as growth, differentiation and signaling. An aberrant expression of MUC1 has been demonstrated in various human cancers. Many studies on MUC1 expression have been conducted on a variety of neoplastic lesions other than head-and-neck region. In this study, an attempt has been made to evaluate the MUC1 immunoexpression in oral squamous cell carcinoma (OSCC) and normal oral mucosa (NOM). AIMS: This study aims to compare and correlate the immunoexpression of MUC1 in NOM and OSCC using immunohistochemical technique. SETTINGS AND DESIGN: Thirty patients of OSCC formed the study group and thirty patients were included in the control group (NOM). Formalin-fixed paraffin wax blocks were prepared from the tissue samples obtained. MATERIALS AND METHODS: Immunohistochemistry (IHC) for MUC1 was performed, and the overall percentage of positive cells along with distribution and localization of immunoexpression was studied. STATISTICAL ANALYSIS: Pearson's Chi-square test was used. P <0.05 was considered to be statistically significant. RESULTS: In OSCC study group, MUC1-positive immunoreaction was observed in 21 (70%) cases out of 30. All the samples in control group were negative for MUC1 immunoexpression. The immunohistochemical expression of MUC1 in OSCC group was statistically significant when compared with normal control group, as P < 0.05 (Pearson's Chi-square). CONCLUSIONS: MUC1 is a reliable biomarker for the diagnosis of OSCC, but further studies are required to prove its role in prognosis.