Oral Squamous Cell Carcinoma and Concomitant Primary Tumors, What Do We Know? A Review of the Literature.

Head and neck cancer is among the top ten cancers worldwide, with most lesions in the oral cavity. Oral squamous cell carcinoma (OSCC) accounts for more than 90% of all oral malignancies and is a significant public health concern. Patients with OSCC are at increased risk for developing concomitant tumors, especially in the oral cavity, due to widely genetically susceptible mucosa to carcinogenic factors. Based on fulfilling specific criteria, these concomitant tumors can be called second primary tumors (SPTs), which can be further categorized into metachronous and synchronous tumors. This research reviews the literature that investigated the concurrent OSCC with second or multiple primaries to improve understanding of the definition, classification guidelines, and its effect on cancer survival. It also highlights the current investigation methods, the variation of standard treatment approaches due to such a phenomenon, and preventive measures discussed in the literature.

Biomimicry and 3D-Printing of Mussel Adhesive Proteins for Regeneration of the Periodontium-A Review.

Innovation in the healthcare profession to solve complex human problems has always been emulated and based on solutions proven by nature. The conception of different biomimetic materials has allowed for extensive research that spans several fields, including biomechanics, material sciences, and microbiology. Due to the atypical characteristics of these biomaterials, dentistry can benefit from these applications in tissue engineering, regeneration, and replacement. This review highlights an overview of the application of different biomimetic biomaterials in dentistry and discusses the key biomaterials (hydroxyapatite, collagen, polymers) and biomimetic approaches (3D scaffolds, guided bone and tissue regeneration, bioadhesive gels) that have been researched to treat periodontal and peri-implant diseases in both natural dentition and dental implants. Following this, we focus on the recent novel application of mussel adhesive proteins (MAPs) and their appealing adhesive properties, in addition to their key chemical and structural properties that relate to the engineering, regeneration, and replacement of important anatomical structures in the periodontium, such as the periodontal ligament (PDL). We also outline the potential challenges in employing MAPs as a biomimetic biomaterial in dentistry based on the current evidence in the literature. This provides insight into the possible increased functional longevity of natural dentition that can be translated to implant dentistry in the near future. These strategies, paired with 3D printing and its clinical application in natural dentition and implant dentistry, develop the potential of a biomimetic approach to overcoming clinical problems in dentistry.

Comparison of Fracture Resistance of Primary Incisors Restored with Different Intracanal-Reinforcement Materials.

AIM: To evaluate the effects of placing short posts made of different restorative materials on the fracture resistance of root canals in primary incisors of primary teeth. MATERIALS AND METHODS: The root canals of 40 extracted primary incisors were prepared and filled with Vitapex and randomly divided into five groups of 8 each. In Groups 1-4, a post space was created and filled with different restorative materials (Tetric® N-Ceram Bulk Fill, AeliteFlo, Filtek Z250 XT, and GC Fuji II LC® capsule), while Group 5 was kept filled with Vitapex as a control. Fracture resistance was measured using a universal testing machine at a 0.5-mm/min crosshead speed. The results were statistically analyzed and compared. RESULTS: The highest fracture resistance was recorded for GC Fuji II LC capsules [439.82 N] and control [423.37 N], while the lowest fracture resistance was recorded for Tetric® N Ceram Bulk Fill (239.91 N). A multiple comparison test showed that the Tetric® N-Ceram Bulk Fill had a significantly lower average value than AeliteFlo (P = 0.030), as well as a significantly lower average value than GC Fuji II LC® capsule (P = 0.001), and a significantly lower average value than the control group (P = 0.002). Multiple comparison tests showed no significant difference between Tetric® N-Ceram Bulk Fill and Filtek Z250 XT (P = 0.39). CONCLUSION: The fracture resistance of primary incisor root canals differs according to the material used for the intracanal posts. Three-millimeter intracanal posts in the primary incisors showed the highest fracture resistance for the teeth restored with GC Fuji II LC capsules and the control.