To investigate the physical properties and the hydration behaviour of the fast-setting bioceramic iRoot FS Fast Set Root Repair Material (iRoot FS) and three other endodontic cements. iRoot FS, Endosequence Root Repair Material Putty (ERRM Putty), gray and white mineral trioxide aggregate (G-MTA & W-MTA), and intermediate restorative material (IRM) were evaluated. The setting time was measured using ANSI/ADA standards. Microhardness was evaluated using the Vickers indentation test. Compressive strength and porosity were investigated at 7 and 28 days. Differential scanning calorimetry (DSC) was employed for the hydration test. iRoot FS had the shortest setting time of the four bioceramic cements (p < .001). The microhardness values of iRoot FS, ERRM Putty and MTA increased at different rates over the 28 days period. At day one, ERRM Putty had the lowest microhardness of the bioceramic cements (p < .001), but reached the same level as MTA at 4, 7 and 28 days. The microhardness of iRoot FS was lower than that of W-MTA at 7 and 28 days (p < .05). The porosity of the materials did not change after 7 days (p < .05). The compressive strength values at 28 days were significantly greater for all bioceramic groups compared to those at 7 days (p < .01). ERRM Putty had the highest compressive strength and the lowest porosity of the evaluated bioceramic cements (p < .05), followed by iRoot FS, W-MTA, and G-MTA, respectively. DSC showed that iRoot FS hydrated fastest, inducing an intense exothermic reaction. The ERRM Putty did not demonstrate a clear exothermic peak during the isothermal calorimetry test. iRoot FS had a faster setting time and hydrating process than the other bioceramic cements tested. The mechanical properties of iRoot FS, G-MTA and W-MTA were relatively similar.

Oral biofilms are highly structured bacterial colonies embedded in a highly hydrated extracellular polymeric substances (EPS) matrix. This study aimed to investigate the characteristics of oral biofilm at different stages of maturation. Oral multispecies biofilms were grown anaerobically from plaque bacteria on collagen coated hydroxyapatite discs in brain heart infusion broth for one and three weeks. The volume of live bacteria and EPS matrix of the biofilms were determined by using corresponding fluorescent probes and confocal laser scanning microscopy. Atomic force microscopy (AFM) was used to quantitatively probe and correlate cell surface adhesion force of biofilms. The surface roughness was quantified in terms of the root mean square average of the height deviations. Adhesion was measured from force–distance data for the retraction of the cell from the surface. The volume of live bacteria and EPS of 3-week-old biofilms was higher than 1-week-old biofilms. The surface roughness value in 1-week-old biofilms was significantly higher than that in 3-week-old biofilms. AFM force–distance curve results showed that the adhesion force at the cell–cell interface was significantly more at-tractive than those at bacterial cells surface of both stages biofilms. Adhesion forces between the AFM tip and the surface of bacterial cell were fairly constant, whereas the cell–cell interface experienced greater adhesion forces in the biofilm's development. As oral biofilms become mature, EPS volume and cell–cell adhesion forces increase while the surface roughness decreases.

Nanomaterials (NMs) have increasingly been used for the diagnosis and treatment of head and neck cancers (HNCs) over the past decade. HNCs can easily infiltrate surrounding tissues and form distant metastases, meaning that most patients with HNC are diagnosed at an advanced stage and often have a poor prognosis. Since NMs can be used to deliver various agents, including imaging agents, drugs, genes, vaccines, radiosensitisers, and photosensitisers, they play a crucial role in the development of novel technologies for the diagnosis and treatment of HNCs. Indeed, NMs have been reported to enhance delivery efficiency and improve the prognosis of patients with HNC by allowing targeted delivery, controlled release, responses to stimuli, and the delivery of multiple agents. In this review, we consider recent advances in NMs that could be used to improve the diagnosis, treatment, and prognosis of patients with HNC and the potential for future research.

Gingival phenotype (GP) has been reported to influence the treatment planning and clinical outcomes in several dental specialties. This study aimed to investigate optimal cutoff values for gingival thickness (GT) measurement at different landmarks to determine GP. The correlations between GT and bone thickness (BT) of buccal alveolar crest were also analyzed. A total of 600 teeth were included. GP was clinically determined by the transparency of a periodontal probe through the gingival margin (TRAN). Measurements for free gingival thickness (GT1), cementoenamel junction gingival thickness (GT2), supracrestal gingival thickness (GT3), subcrestal 1 mm gingival thickness (GT4) and BT at 1, 3 mm apical from the alveolar crest edge (BT1 and BT2) were assessed on cone-beam computed tomography (CBCT) images. Spearman's correlation coefficient was used to evaluate correlations between GT and BT. The optimal cutoff values of GT using CBCT method to discriminate GP were 0.75 mm for GT1, 0.85 mm for GT2, 1.15 mm for GT3 and 0.45 mm for GT4. There was significantly positive correlation between GT and BT at all levels (r: 0.375–0.903). The correlations between GT3 and BT (r: 0.789–0.903) were strong, while correlations between GT4 and BT were weak (r: 0.375–0.467). The optimal cutoff values of gingival thickness using CBCT method to discriminate gingival phenotype at each gingival landmark were determined. The supracrestal gingival thickness might be an indicator of buccal alveolar crest bone thickness, which could provide valuable perspectives on clinical diagnosis, treatment planning and decision-making.