Intaglio Surface Adaptation of Removable Partial Denture Framework Fabricated by Various Data Acquisition Techniques and Fabrication Approaches.

OBJECTIVES: The aim of this study was to compare intaglio surface adaptation of the removable partial denture framework among various data acquisition techniques and fabrication approaches using three-dimensional comparison by metrology software. MATERIALS AND METHODS: The partial edentulous typodont model with five digital superimposition landmarks was duplicated and scanned for the digital reference model. Three approaches were the conventional lost-wax (group I; LWT, n = 5), intraoral digital impressions combined with PolyJet printing and lost-wax (group II; IP-LWT, n = 5), and extraoral digital impressions combined with PolyJet printing and lost-wax (group III; EP-LWT, n = 5). Each framework was scanned and superimposed with the reference model. The misfits at 53 locations were measured. STATISTICAL ANALYSIS: Data were statistically analyzed by one-way analysis of variance, followed by Tukey's honestly significant difference for pairwise comparisons (p < 0.05). RESULTS: Significant differences were found between three approaches at the reciprocal arm, terminal part of the retentive arm, rest, and major connector (p < 0.05). In the LWT group, the reciprocal arm and palatal vault region of major connector had the lowest misfits, but the highest misfit was found in the midline region (p < 0.001). In the IP-LWT group revealed the most excessive contact at the terminal part of the retentive arm (-0.111 ± 0.038 mm, p = 0.031), with the highest misfit at the rest area (p < 0.001). CONCLUSION: A difference in adaptation was found in several removable partial denture framework components among three approaches. The LWT group had a better adaptation than other groups. Nevertheless, a clinically acceptable adaptation was seen in all three approaches.

The Akt/mTOR pathway is activated in verrucous carcinoma of the oral cavity.

BACKGROUND: The Akt/mTOR pathway is activated in many malignancies, including oral squamous cell carcinoma (OSCC). However, the role of the Akt/mTOR pathway in oral verrucous carcinoma (OVC), a low-grade variant of OSCC, remains unknown. Thus, the objective of this study was to investigate the activation level of important markers of the Akt/mTOR pathway in OVC and to compare the results with OSCC samples. METHODS: The expression of p-Akt (Thr308), p-Akt (Ser473), and p-RPS6 was evaluated by immunohistochemistry in 30 OSCC cases, 18 OVC cases, and 30 control cases (normal epithelium overlying fibromas). Statistical analysis was performed to determine the differences in protein expression between samples. RESULTS: All OVC cases were positive for p-Akt (Thr308), p-Akt (Ser473), and p-RPS6. There were significant differences in expression level of all studied proteins between OVC and control, as well as between OVC and OSCC. However, OVC showed significant lower staining scores than OSCC. CONCLUSIONS: Our findings demonstrate that the Akt/mTOR pathway is upregulated in OVC, indicating a role for this pathway in the development and progression of this malignancy.