The anti-plaque effect of high concentration sodium bicarbonate dentifrice on plaque formation and gingival inflammation, irrespective to individual polishing technique and plaque quality.

AIM: To assess the anti-plaque effect of a high concentration sodium bicarbonate dentifrice on plaque formation, and gingivitis, as compared to a control toothpaste, irrespective of individual brushing technique and plaque quality. METHODS: The experimental gingivitis model, with a split-mouth design was used to assess the anti-plaque effect of a high concentration sodium bicarbonate dentifrice on plaque formation. By producing individual fitted trays, the toothpaste was applied in the test quadrant and a control dentifrice in the contralateral. The participants used the individual fitted trays for 1 min every morning and evening, for 21 days. In this period, the participants was only allowed to brush the teeth in the opposite jaw, as usual. Twenty healthy individuals successfully completed the study. RESULTS: At 21 days, there was no statistically significant difference between test quadrant and control quadrant with regard to plaque indices, gingival index and number of bleeding sites. CONCLUSION: This study demonstrated that the high concentration sodium bicarbonate dentifrice used did not produce statistically significant anti-plaque effect compared to the control dentifrice, in terms of Plaque- and Gingival Indices, number of bleeding sites or by Quigely and Hein, the Turesky modification Plaque Index, irrespective of brushing technique and individual plaque quality. TRIAL REGISTRATION: Regional Committee for Medical Research and Ethics, South-East Norway in 2021 (REK.2021/370116). CLINICAL TRIAL REGISTRATION: NCT05441371 (First registered 09/06/2022, First posted 01/07/2022) ( http://www. CLINICALTRIALS: gov ). (Retrospectively registered).

Integrin α11 is overexpressed by tumour stroma of head and neck squamous cell carcinoma and correlates positively with alpha smooth muscle actin expression.

BACKGROUND: Cancer-associated fibroblasts (CAFs) were shown to be important for tumour progression in head and neck squamous cell carcinomas (HNSCCs). Their heterogeneity and lack of specific markers is increasingly recognized. Integrin α11 was recently shown to be expressed by CAFs and might serve as a specific CAF marker. AIM: To investigate integrin α11 expression and its correlation with the expression of a well-known marker of CAF, alpha smooth muscle actin (α-SMA), in HNSCC. METHODS: Fresh frozen (FF) and formalin-fixed paraffin-embedded (FFPE) samples from healthy volunteers (n = 24), oral lichen planus (OLP) (n = 32) and HNSCC (n = 106) were collected together with clinical data after ethical approval. Immunohistochemistry to detect integrin α11 and α-SMA was performed on FF and FFPE samples. qPCR for integrin α11 (ITGA11) and α-SMA (ACTA2) was performed on FF samples. Data were analysed using chi-square test and Kaplan-Meier survival analysis. RESULTS: Significantly higher levels of integrin α11 and α-SMA at both protein and mRNA levels were found in HNSCC vs. normal controls and OLP. A strong correlation was found between integrin α11 and α-SMA expression, and double staining showed their colocalization. Both integrin α11 and α-SMA were detected surrounding metastatic islands. Expression of α-SMA at tumour front but not tumour centre correlated with patient survival. CONCLUSION: Integrin α11 was overexpressed in HNSCC stroma and colocalized with α-SMA. Expression of α-SMA at tumour front but not tumour centre had prognostic value for survival, pinpointing the importance of assessing tumour front when evaluating stromal molecules as prognostic biomarkers.