Editorial: Biofabrication and Biopolymeric Materials Innovation for Musculoskeletal Tissue Engineering cook

The human musculoskeletal system provides form, support, stability, and movement to the body. It is made up of the bones of the skeleton, muscles, cartilage, tendons, ligaments, joints, and other connective tissues. The primary functions of the musculoskeletal system include supporting the body, allowing motion, and protecting vital organs. The skeletal portion of the system serves as the main storage system for calcium and phosphorus and contains critical components of the hematopoietic system (Li and Niu, 2020). Musculoskeletal Disorders (MSDs) include injuries and diseases that primarily affect the movement of the human body. They are characterized by pain and limitations in mobility, dexterity, and overall level of functioning, reducing patients’ ability to work and maintain a good quality of life. A recent analysis of Global Burden of Disease data showed that approximately 1.71 billion people globally have musculoskeletal conditions (Woolf and Pfleger, 2003). MSDs such as osteoarthritis, rheumatoid arthritis, psoriatic arthritis, gout, and ankylosing spondylitis affect joints (McInnes and Schett, 2011; Loeser et al., 2012; Litwic et al., 2013); osteoporosis, osteopenia and associated fragility fractures, as well as traumatic fractures, affect bones (Florencio-Silva et al., 2015); sarcopenia affects muscles, and back and neck pain affect the spine of the human body

Advances in Peptide-Based Hydrogel for Tissue Engineering

The development of peptide-based materials has emerged as one of the most challenging aspects of biomaterials in recent years. It has been widely acknowledged that peptide-based materials can be used in a broad range of biomedical applications, particularly in tissue engineering. Among them, hydrogels have been attracting considerable interest in tissue engineering because they mimic tissue formation conditions by providing a three-dimensional environment and a high water content. It has been found that peptide-based hydrogels have received more attention due to mimicking proteins, particularly extracellular matrix proteins, as well as the wide variety of applications they are capable of serving. It is without a doubt that peptide-based hydrogels have become the leading biomaterials of today owing to their tunable mechanical stability, high water content, and high biocompatibility. Here, we discuss in detail various types of peptide-based materials, emphasizing peptide-based hydrogels, and then we examine in detail how hydrogels are formed, paying particular attention to the peptide structures that are incorporated into the final structure. Following that, we discuss the self-assembly and formation of hydrogels under various conditions, as well as the parameters to be considered as critical factors, which include pH, amino acid composi- tion within the sequence, and cross-linking techniques. Further, recent studies on the development of peptide-based hydrogels and their applications in tissue engineering are reviewed

Dental decay and associated factors in Iranian three-year-old children

Objectives The aim of this study was to assess dental caries and associated factors in children aged three years living in Varamin, Iran. Methods Eight hundred and fifteen three-year-old children were recalled randomly through the records existing in healthcare centers of Varamin, Iran. Two hundred and three mothers were also examined to assess the relationship between the oral health of mothers and children. Dental examinations were performed by two calibrated senior dental students using decayed missed filled teeth (dmft/DMFT) indices according to the WHO oral health survey basic methods. Demographic and oral-health care behavior data were collected using a standard  questionnaire.Results The mean DMFT was 2.69 ± 3.492 years (range 0–19 years). No significant difference was seen in dental care behavior of males and females; 43.4% of children were caries-free. A positive correlation was detected between mother’s DMFT and child’s dmft (r = 0.27, P < 0.0001). Adjusted regression analysis showed that dental caries was observed more frequently in children having mothers with DMFT> 12 compared to mothers with DMFT less than 6 (CR: 1.55; 95% CI: 1.02–2.35) after controlling for child’s sex and behaviors.Conclusion This study showed that more than half of the three-year-old children experience dental caries and there is a positive correlation between the DMFT of mothers and dmft of their children

Microleakage comparison of resin modified glass ionomer and OrthoMTA used as a coronal barrier in nonvital teeth bleaching

Background and Aim: Common causes of dental discoloration include trauma, drugs, genetic defects, decay, and age. In order to correct discoloration of pulpless teeth, internal bleaching is recommended. The aim of this study was to compare microleakage of resin modified glass ionomer and OrthoMTA used as an intraorifice barrier in non-vital bleaching. Methods: In this experimental study, 36 extracted mandibular premolars were selected and randomly divided into two experimental (n = 16) and two control groups (n = 2). 2mm of OrthoMTA and RMGI cements were placed as intraorifice barriers in the experimental groups. Subsequently, we placed a mixture of sodium perborate and 30% hydrogen peroxide as internal bleaching material into the canal and replaced it every three days. Leakage was measured using pH diffusion method by a digital PH meter. Data were statistically analyzed by using T- independent test and repeated measures and variance analysis (P<0.05). Results: The pH value of the negative control group was as same as the PH of normal saline while the PH value of positive control group was significantly higher than those of other groups. PH values of Ortho MTA and RMGI at the baseline and on the first, sixth and ninth day did not show significant differences with one another, while microleakage of OrthoMTA group was significantly lower on the third day. Conclusions: In general, OrthoMTA had less leakage than RMGI but both materials can be used as suitable barriers for internal tooth bleaching Keywords: Tooth bleaching, OrthoMTA, Glass ionomer, leakag

A Comparative Investigation of the Microleakage of Biodentine and Mineral Trioxide Aggregate as Coronal Barrier in Nonvital Bleaching

Background: Internal bleaching is recommended to correct the discoloration of pulpless teeth. This study aimed to compare the microleakage of biodentine and mineral trioxide aggregate (MTA) used as an intracanal barrier in non-vital bleaching. Methods: An experimental study was performed in which 36 extracted mandibular premolars were randomly divided into two experimental groups (n= 16) and two control groups (n= 2). In experimental groups, 2mm of OrthoMTA and biodentine cement were placed as intracanal barriers. The control groups were prepared similar to experimental groups, except that in positive control group the orifice barrier material was not used and in negative control group the whole root surface was covered with nail polish and orifice barrier material was not used. Subsequently a mixture containing sodium perborate and 30% hydrogen peroxide was placed into the pulp chambers and replaced every three days. Microleakage was measured using a pH diffusion method by digital pH meter. pH was checked before placement and at days 1, 3, 6, and 9 after placement. Data analysis was done in SPSS V24 Results: The pH value in negative control group was similar to that in normal saline group, while the pH value in positive control group was found to be significantly higher than other groups (P< 0.05). Nosignificant differences were seen in pH values between the experimental groups at baseline and days 1 and 6, but pH values of biodentine were significantly higher than orthoMTA at days 3 and 9 (P< 0.05). Conclusions: MTA can be used as an efficient orifice barrier during internal bleaching, specifically in cases where there is probability for cervical root resorption. Keywords: tooth bleaching, mineral trioxide aggregate, dental leakag