During the last decade, oral cytology has once again become the focus of scientific research. This new interest is due to the introduction of a cytobrush for cell collection as well as a computer-assisted analysis (Oral CDx). Although promising, the sensitivity and specificity of conventional oral brush cytology remains limited. To circumvent the problems and improve the accuracy, various adjunctive analytical methods have been attempted. DNA analysis, immunocytochemical and molecular analysis are suggested methodological cytology approaches to improve the validity of oral brush cytology. An increase in sensitivity (up to 100%) and specificity (up to 100%) of oral brush biopsy has been reported on localized pre-malignant and malignant lesions. Oral brush biopsy probably will not replace histopathology in the definitive diagnosis of oral cancer, but it might be valuable for the prevention of misdiagnosis of clinically doubtful oral lesions and for the monitoring of lesions that might proceed on to oral cancer.

Improvement of survival rate and quality of life after treatment of oral squamous cell carcinoma as well as cost reduction requires reliable early diagnosis of the tumor and its precursor lesions. Four different screening methods are primarily employed: toluidine blue staining (visually detected lesions: sensitivity 70-100%, specificity 25-67%), photodynamic diagnosis (sensitivity 94-99%, specificity 60-89%), autofluorescence (no data published so far) and modern oral cytology (sensitivity 80%,specificity 95-100%). Additional analytic procedures such automated image analysis, DNA image cytometry and immunocytochemistry can be used to enhance the low sensitivity of conventional oral cytology. While these methods have achieved sensitivity and specificity approaching 100%, the studies involved clearly-defined entities such as large oral squamous cell carcinomas and aphthae. The modern and methodenhanced oral cytology is a simple, value-based and inexpensive tool for early diagnosis of oral squamous cell carcinoma and its precursor lesions. Surgical biopsy and histopathological examination remains the gold standard for definitive diagnosis.

Cellular senescence is a restricting factor for regenerative therapies with somatic stem cells. We showed previously that the onset of cellular senescence inhibits the osteogenic differentiation in stem cells of the dental follicle (DFCs), although the mechanism remains elusive. Two different pathways are involved in the induction of the cellular senescence, which are driven either by the cell cycle protein P21 or by the cell cycle protein P16. In this study, we investigated the expression of cell cycle proteins in DFCs after the induction of cellular senescence. The induction of cellular senescence was proved by an increased expression of β-galactosidase and an increased population doubling time after a prolonged cell culture. Cellular senescence regulated the expression of cell cycle proteins. The expression of cell cycle protein P16 was up-regulated, which correlates with the induction of cellular senescence markers in DFCs. However, the expression of cyclin-dependent kinases (CDK)2 and 4 and the expression of the cell cycle protein P21 were successively decreased in DFCs. In conclusion, our data suggest that a P16-dependent pathway drives the induction of cellular senescence in DFCs.

Background New medicinal and surgical oncological treatment strategies not only improve overall survival rates but continually increase the importance of Health-Related Quality of Life (HRQOL). The purpose of this retrospective cross-sectional study was to analyze HRQOL of patients with oral squamous cell carcinoma after ablative surgery and to evaluate predictive factors for HRQOL outcome. Methods The study included 88 patients with histologically confirmed oral squamous cell carcinoma of whom 42 had undergone local reconstruction (LR) and 46 microvascular reconstruction (MVR). During follow-up, all patients completed the University of Washington Quality of Life Questionnaire (UW-QOL) containing 12 targeted questions about the head and neck. Descriptive analyses were made for the tumor site, the T-stage, and adjuvant therapies. HRQOL was compared between the LR and the MVR group with parametric tests. Further analyses were impact of the tumor site, the T-status, and the time from surgery to survey on HRQOL. Statistics also included multivariate correlations and different interaction effects. Results HRQOL in the LR group was ‘very good’ with 84.3 ± 13.7 and ‘good’ in the MVR group with 73.3 ± 16.5 points. The physical domains swallowing ( p = 0.00), chewing ( p = 0.00), speech ( p = 0.01), taste ( p = 0.01), and pain ( p = 0.04) were significantly worse in the MVR group. An increase in the T-status had a significant negative effect on swallowing ( p = 0.01), chewing ( p = 0.01), speech ( p = 0.03), recreation ( p = 0.05), and shoulder ( p = 0.01) in both groups. Regarding the tumor site and subsequent loss of HRQOL, patients with squamous cell carcinoma on the floor of the mouth had significantly worse results in the categories pain ( p = 0.002), speech ( p = 0.002), swallowing ( p = 0.03), activity ( p = 0.02), and recreation ( p = 0.01) than patients with tumors in the buccal mucosa. Speech ( p = 0.03) and pain ( p = 0.01) had improved 1 year after surgery. Conclusion Patients with flap reconstruction because of oral squamous cell carcinoma showed very good overall HRQOL. Outcomes for microvascular reconstruction were good, even in the case of larger defects. The T-status is a predictor for HRQOL. Swallowing, chewing, speaking, taste, and pain were the most important issues in our cohort. Implementing HRQOL questionnaires for the assessment of quality of life could further increase the treatment quality of patients with oral cancer.

BACKGROUND: In a preliminary trial, we were able to show first promising results in the analysis of perioperative and postoperative perfusion of free flaps by means of a new monitoring system for detecting thrombotic vessel occlusion before clinical signs become evident. OBJECTIVE: We investigated whether flap monitoring by measuring perfusion-dependent parameters differs between radial forearm and fibular free flaps and whether a threshold value requiring anastomosis revision could be determined. METHODS: 37 radial forearm flaps (RF) and 15 fibular flaps (FF) were harvested and transplanted. Perfusion was determined by measuring a fluorescent oxygen sensor foil covering a flap's skin surface with a handheld fluorescence microscope . The sensor contained an oxygen reservoir, which was consumed by the tissue corresponding to the perfusion status of the flap. Measurements were done before explantation, after successful anastomosis and one day after surgery. RESULTS: We found a significant difference (p < 0.005) in the relative transdermal oxygen consumption (RTOC) between clinically well-perfused grafts (RF: mean: 0.13 ± 0.08; FF: mean: 0.15 ± 0.07) and clinically poorly perfused grafts (RF: mean: 0.40 ± 0.09; FF: mean: 0.55 ± 0.28).A threshold RTOC value of 0.3 for differentiating between well-perfused and poorly perfused flaps was confirmed for both RF and FF.