Investigating the implant position reproducibility of optical impressions obtained using an intraoral scanner and 3D-printed models fabricated using an intraoral scanner.

PURPOSE: This study aims to examine the effect of the size of the intraoral scanning area on implant position reproducibility and compare the implant position reproducibility of plaster models fabricated using the silicone impression technique, the digital model of an intraoral scanner, and three-dimensional (3D)-printed models fabricated using an intraoral scanner. METHODS: Scanbodies were attached to an edentulous model with six implants (master model) and were scanned using a dental laboratory scanner to obtain basic data. The plaster model was fabricated using the open-tray method (IMPM; n = 5). The master model was then scanned in various implant areas using an intraoral scanner to obtain data (IOSM; n = 5); the scanning data of six scanbodies were used to fabricate the 3D-printed models (3DPM; n = 5) using a 3D printer. Scanbodies were attached to the implant analogs of the IMPM and 3DPM models and data were obtained using a dental laboratory scanner. The basic data and IMPM, IOSM, and 3DPM data were superimposed to calculate the concordance rate of the scanbodies. RESULTS: The concordance rate of intraoral scanning decreased as the number of scanbodies increased. Significant differences were observed between the IMPM and IOSM data, and between the IOSM and 3DPM data; however, the IMPM and 3DPM data did not differ significantly. CONCLUSIONS: The implant position reproducibility of the intraoral scanner decreased with an increase in the scanning area. However, ISOM and 3DPM may provide higher implant position reproducibility than plaster models fabricated using IMPM.

Post-Traumatic Trigeminal Neuropathic Pain after Dental Implant Surgery and the Injustice Experience Questionnaire.

Painful post-traumatic trigeminal neuropathy (PTTN) is a known complication of dental implant therapy. Patients with PTTN develop sensory abnormalities in the orofacial region, which may be a psychosocial aspect, and dentists should assess somatosensory testing and psychosocial factors. The patients were assessed using quantitative sensory testing (QST). A 64-year-old female presented with allodynia of the left lower lip that occurred after a surgical implant procedure. Persistent pain started 4 months after the placement of two dental implants in the mandible. Sensory testing of these areas revealed warm hyposensitivity and mechanical hypersensitivity of the mandibular region. We also assessed PTTN-related perceived injustice using the Injustice Experience Questionnaire. The patient refused medication therapy such as pregabalin; therefore, autogenic training was adopted as an alternative management strategy. We conclude that for expensive dental procedures, such as implant placement, sufficient consensus should be obtained preoperatively before proceeding with surgery.

Electrolytically generated acid functional water inhibits NF-κB activity by attenuating nuclear-cytoplasmic shuttling of p65 and p50 subunits.

BACKGROUND: Human ß-defensin 2 (hBD2) gene expression is dependent on nuclear factor kappa B (NF-κB) activity. We have previously demonstrated that electrolytically generated acid functional water (FW) induces the expression of hBD2 in the human oral squamous cell carcinoma (OSCC) cell line Ca9-22. However, the induction was not dependent on NF-κB activity; in fact, FW inhibited NF-κB activity. Therefore, we hypothesized that FW might reduce spontaneous interleukin 8 (IL-8) secretion by Ca9-22 cells, which is heavily dependent on NF-κB activity. This study aimed at demonstrating the inhibitory effect of FW on NF-κB activity. METHODS: Ca9-22 cells were incubated with FW, and spontaneous IL-8 secretion was observed by enzyme-linked immunosorbent assay. Luciferase assay was performed using the 5'-untranslated region of the IL-8 gene. The steps of NF-κB activation blocked by FW were evaluated by localization of the NF-κB subunits p65 and p50 by immunofluorescence staining. Western blotting was further performed to confirm the changes in NF-κB subunit localization. RESULTS: The Ca9-22 cells spontaneously secreted IL-8, which was rapidly and drastically inhibited by FW treatment. The luciferase assay demonstrated the inhibitory action of FW, which was diminished by deletion of the NF-κB binding site from this construct. FW treatment altered the distribution of both the p65 and p50 subunits. P65, which was localized in the nucleus during the resting state, moved to the cytoplasm after FW treatment, whereas, p50, localized in the cytoplasm during the resting state, moved to the nucleus subsequent to FW treatment. CONCLUSIONS: The results from this study indicate that FW might inhibit spontaneous IL-8 secretion by redistribution of the NF-κB subunits within the cells.

Cancer cell-derived IL-8 induces monocytic THP1 cells to secrete IL-8 via the mitogen-activated protein kinase pathway.

Aberrant activity of transcription factors in oral squamous cell carcinoma (OSCC) results in the spontaneous secretion of various cytokines and chemokines. Among them, IL-8, owing to its angiogenic activity, promotes the growth of OSCCs. In the present study, we examined the role of IL-8 secreted by OSCCs, on the angiogenic activity of monocytic THP1 cells. Culture supernatant (Ca-sup) augmented IL-8 secretion by THP1 cells, which was found to be significantly reduced following the removal Ca9-22-derived IL-8 from the Ca-sup. IL-8 induction was regulated at the transcriptional level, because real-time PCR demonstrated the augmented IL-8 messenger RNA (mRNA) expression. We further performed the luciferase assay using the 5'-untranslated region of IL-8 gene. Contradictory to our speculations, luciferase activity was not augmented by Ca-sup stimulation. NF-κB-independent IL-8 induction was further confirmed by pre-treating THP1 cells with NF-κB-specific inhibitors. To elucidate the signaling pathway, THP1 was pre-treated with MEK inhibitors. The results demonstrated that pre-treatment of cells with MEK inhibitor drastically reduced IL-8 levels, suggesting the role of MEK. Moreover, Ca-sup was found to increase ERK1/2 phosphorylation in a time-dependent manner. These results indicated that OSCC-derived IL-8 appears to activate angiogenic activity in monocytes within the tumor microenvironment via the mitogen-activated protein kinase (MAPK) pathway.