With growing evidence on the role of inflammation in carcinogenesis, the presence of a systemic inflammatory response has been proposed as having prognostic significance in a wide range of cancers. The aim of the study was to assess the value of pretreatment neutrophil-to-lymphocyte ratio (NLR) in predicting disease-specific survival (DSS) in patients with oral cancer undergoing preoperative chemoradiotherapy. A cohort of 97 patients with locally advanced oral squamous cell carcinoma receiving preoperative chemoradiotherapy was retrospectively examined. The impact of NLR and other potential prognostic factors on DSS was assessed with the Kaplan-Meier method and multivariate Cox regression analysis. Sixty-nine patients had a high pretreatment NLR, with NLR > 1.9 considered as high according to receiver operating characteristic curve analysis. In univariate analysis, high pretreatment NLR (p = 0.018), positive perineural invasion (p < 0.001) and advanced pathologic TNM stage after neoadjuvant therapy (p < 0.001) were predictive of shorter DSS. In multivariate analysis, advanced pathologic TNM stage after neoadjuvant therapy (HR 1.71, 95 % CI 1.17-2.48, p = 0.005), positive perineural invasion (HR 3.67, 95 % CI 1.11-12.13, p = 0.033) and high pretreatment NLR (HR 10.37, 95 % CI 1.28-84.08, p = 0.029) remained independently associated with poor DSS. A high pretreatment NLR is a significant independent predictor of shorter DSS in patients with oral cancer receiving preoperative chemoradiotherapy.

In the present study, two biphasic calcium phosphate biomaterials (BCP) with HA/TCP ratios of 50/50 and 30/70 were obtained from a pure HA biomaterial. The biomaterials which showed the same three-dimensional geometry were implanted into corticocancellous costal defects of sheep. In the specimens of all three biomaterials, abundant bone formation, mineral dissolution from the biomaterial scaffolds, and active cellular resorption of the scaffolds was present after 6 and 12 months. Backscattered electron microscopy showed bone invasion into the pores of the scaffolds and micromechanical interlocking at the bone/biomaterial interface without intervening soft tissue. The pattern of bone formation and scaffold resorption was different for cortical and cancellous bone. No time-based effect, however, was observed. Overall, the BCP biomaterials had formed significantly more bone than the HA biomaterial. Also, scaffold resorption, which was followed by a replacement with newly formed bone, was significantly higher in the BCP biomaterials. Although no significant differences were observed between both BCP biomaterials, the present study had confirmed the assumption that HA/TCP compounding was suitable to improve bone formation and scaffold resorption in the investigated biomaterials and at the same time maintain the osteoconductive properties of the scaffolds.

The overall accuracy of a novel surgical computer-aided navigation system for placement of endosseous implants was evaluated. Five dry cadaver mandibles were scanned using high resolution computed tomography (HRCT). The position of four interforaminal dental implants was planned on the computer screen and transferred to the cadaver mandibles using VISIT, a surgical navigation software developed at the Vienna General Hospital. The specimens were HRCT-scanned again to compare the position of the implants with the preoperative plan on reformatted slices after matching of the pre- and postoperative data sets using the mutual information technique. The overall accuracy was 0.96 +/- 0.72 mm (range 0.0-3.5 mm). No perforation of the mandibular cortex or damage to the mandibular canal occurred. We conclude that computer-aided implant surgery can reach a level of accuracy where further clinical developments are feasible.

No abstract