In vitro effects of particulate bone substitute materials on the resorption activity of human osteoclasts.

Much research has been done on bone cells, but only a few studies deal with biomaterial-induced effects on human osteoclasts, which may take on an important role in the successful regeneration of bone. In order to highlight such effects, human peripheral blood mononuclear cells (PBMCs) were extracted from venous blood, differentiated to osteoclasts and then cultured in, the presence of five particulate hydroxyapatite (HA)/ß-tricalcium phosphate (TCP) biomaterials, on bovine bone slices and glass cover slips. The biomaterials, AlgOSS 50/50 (50 % HA/50 % TCP), AlgOSS 20/80 (20 % HA/80 % TCP), Algipore (98 % HA), Cerasorb (100 % TCP) and Bio-Oss (100 % HA) were chosen to assess their influence on cell morphology and numbers. Light microscopic evaluation was performed during ongoing cell culture. After 21 d of cultivation, the biomaterial-induced effects on osteoclastic resorption of the bone slices were evaluated by scanning electron microscopy (SEM). Osteoclast-like cells were identified by TRAP staining. All five biomaterials showed larger area fractions of resorbed bone than the control (5.6 ± 6.8 %), as measured on SEM images. The purely hydroxyapatite-based Algipore (9.8 ± 9.7 %) and Bio-Oss (7.9 ± 8.8 %) showed significantly elevated area fraction rates (p ≤ 0.05) of bone resorption. Light microscope evaluation revealed a significant, but inhibiting effect of Cerasorb (p = 0.05). These data indicated that introducing of small biomaterial hydroxyapatite particles may have improved the performance of bone substitute materials.

Medical practitioners' educational competence about oral and oropharyngeal carcinoma: a systematic review and meta-analysis.

Medical practitioners' (MP) role is pivotal in primary prevention, early diagnosis, prompt referral and effective management of oral and oropharyngeal carcinomas (OC/OPC), which raises the importance of their effective OC/OPC education at all levels of medical education. The purpose of this systematic review was to summarise the available scientific evidence about their educational competence in dealing with OC/OPC. We made a systematic search of papers in the English language in MEDLINE, Scopus, Cochrane Library CENTRAL and CINAHL databases from their inception until December 2018. Overall, 23 cross-sectional and three interventional studies have been selected for the systematic review and 18 of these were included in the meta-analyses. Excluding tobacco use (synthesised estimate of 95% of respondents identified tobacco as an OC/OPC risk factor, 95% CI of synthesised estimate 92% to 97%) and alcohol consumption (65%, 95%CI 52% to 77%), less than half of MP (approximately) were knowledgeable about important OC/OPC risk factors including human papilloma virus (42%, 95% CI 30% to 54%), poor diet (34%, 95% CI 17% to 54%), and advancing age (45%, 95% CI 21% to 70%). There was a low to moderate level of awareness among MP regarding common precancerous oral lesions involving leukoplakia (56%, 95% CI 32% to 79%), erythroplakia (30%, 95% CI 8% to 58%), and oral lichen planus (13%, 95% CI 0 to 41%). Moderate knowledge was also recorded about frequent sites of OC development involving the tongue (48%, 95% CI 33% to 64%) and floor of the mouth (37%, 95% CI 19% to 57%). Most MP enquired about tobacco use (86%, 95% CI 74% to 96%), and alcohol consumption (73%, 95% CI 47% to 94%) during history taking, and expressed willingness to be given supplementary OC/OPC education (78%, 95% CI 54% to 96%), as well. With regard to the incidence of intraoral screening, 27% of MP (95% CI 12% to 46%) make an intraoral examination as a routine. Interestingly, studies from each continent yielded significantly different outcomes to some research questions in the review. From the MP's perspective, clinical time restrictions and deficiencies in organised training were recognised as the main barriers towards their OC/OPC educational competence. The findings of this systematic review indicated the existence of deficiencies in knowledge and misconceptions, neglected preventive responsibilities, and associated barriers towards OC/OPC. A need for improved OC/OPC training at all levels of medical education is required to increase competence worldwide.

Anticoagulant-induced changes on antibiotic concentrations in the serum and bones.

The aim of this study was to determine whether the co-administration of acenocoumarin as anticoagulant and certain quinolones, i.e., cefapirin, pefloxacin and ciprofloxacin increased the levels of the given antibiotics and whether this resulted in a prolongation of prothrombin time. Seventy male albino Wistar rats aged 8-10 weeks and weighed 170 +/- 14 g were used and divided into seven groups (I, II, III, IV, V, VI, VII: n=10). The rats in group I received cefapirin via 1 g/kg/8h im injection. Group II received cefapirin via of 1 g/kg/8h im injection and 0.1 mg/kg/24h p.o. acenocoumarin. Group III received ciprofloxacin 0.18 mg/kg/24h im. Group IV received ciprofloxacin 0.18 mg/kg/24h im and 0.1 mg/kg/24h p.o. acenocoumarin. Group V received 10 mg/kg/24h pefloxacin im. Group VI received 10 mg/kg/24h pefloxacin im and 0.1 mg/kg/24h p.o. acenocoumarin while Group VII received only acenocoumarin 0.1 mg/kg/24h p.o. Drug administration was performed over a total of 5 doses in order to obtain steady state concentrations in the plasma and tissues. The animals were sacrificed by decapitation 2 h after the last antibiotic administration. Prothrombin time and antibiotic concentrations in the serum, femur and mandible were assessed. In the study, all the antibiotics were found to prolong prothrombine time following acenocoumarin administration. In addition, perfloxacin and ciproflaxin concentrations were increased in the serum and mandible after acenocoumarin treatment. Cepafirin levels remained unaffected after the administration of this anticoagulant. In conclusion, anticoagulant and quinolone co-administration led to significant pharmacokinetic interactions. Thus particular attention should be paid in the case of these drugs being used in combination in clinical practice.

Importance of chewing, saliva, and swallowing function in patients with advanced oral cancer undergoing preoperative chemoradiotherapy: a prospective study of quality of life.

The primary objective of this study was to investigate the quality of life (QOL) of patients with oral squamous cell carcinoma (OSCC) undergoing curative neoadjuvant chemoradiotherapy followed by radical tumour resection and simultaneous oral cavity reconstruction, using two validated questionnaires. A secondary objective was to assess clinical variables predicting post-treatment dysfunction in chewing, saliva, and swallowing. Thirty-five patients with locally advanced OSCC who underwent preoperative chemoradiotherapy were recruited prospectively. All patients completed both the University of Washington Quality of Life version 4 questionnaire (UW-QOL) and the Functional Assessment of Cancer Therapy-Head & Neck version 4 questionnaire (FACT-H&N). UW-QOL and FACT-H&N items were associated with clinical variables. Nearly three-quarters of OSCC patients perceived good to excellent levels of overall QOL after preoperative chemoradiotherapy. Chewing difficulties, decreased salivary function, and swallowing dysfunction were the most frequent complaints of OSCC patients. Items related to food intake were significantly worse in OSCC patients older than 60 years and those with T4 tumours, as well as those without alcohol intake. Chewing, saliva, and swallowing are the most significant issues in patients with OSCC undergoing preoperative chemoradiotherapy. The results of this study may help guide treatment decisions for OSCC patients based on more accurate expectations of adverse effects of cancer treatment.

Tricalcium phosphate-based biocomposites for mandibular bone regeneration--A histological study in sheep.

The present study investigated the suitability of three different absorbable biocomposites for the repair of critical sized bone defects created at the mandibular angle of adult sheep. Each biocomposite was composed of a three-dimensional individualized polylactide scaffold, containing a tricalcium phosphate biomaterial (chronOS). Either autologous bone marrow (chOS/BoneMarrow) or coagulation factor XIII (chOS/FactorXIII) was added to the biomaterial for osteopromotion. Venous whole blood (chOS/Blood) added to the biomaterial served as a control. A total of 18 adult sheep were used for implantation studies, subdivided into three groups of six animals each. After 12 weeks of observation, the animals were sacrificed and the mandibles were retrieved for qualitative and quantitative histologic assessment within three regions of interest (transitional zone, center, and periphery) throughout the biocomposites. Successful bone regeneration was defined by the absence of scaffold deformation and the presence of new bone formation within the biocomposites. In histomorphometry, only chOS/BoneMarrow showed elevated area fractions of newly formed bone in all regions of interest (transitional zone 50.7 ± 7.5, center 31.9 ± 9.3, periphery 23.1 ± 13.5). This led to preservation of the macroscopic scaffold structure in all specimens. Zero hurdle regression confirmed this by validating the factor biocomposite as significant (p < 0.001) for regeneration success. In our experiment, chOS/BoneMarrow was the only biocomposite passing the hurdle of regeneration in all three regions of interest. In contrast, bone formation was less pronounced and uniform in chOS/FactorXIII and chOS/blood-containing specimens. In these groups, scaffolds showed obvious to significant deformation. Overall, autologous bone marrow showed the most promising results in our experimental setting. As opposed to reports in the literature, we could not confirm the suitability of coagulation factor XIII to promote bone formation, since bone formation rates were comparable only to those of the control venous blood.

Is failure of condylar neck osteosynthesis predictable based on orthopantomography?

BACKGROUND: Osteosynthesis failure rates of 11.3% with 1 miniplate, 6.7% with 2 miniplates, and 4.4% with a single Medartis condyle plate were reported in previous studies of our clinic. Current science is still focused on the osteosynthesis material. Besides clinical parameters, conventional radiographs are still the first choice to detect osteosynthesis failures. This study scrutinized several factors assessable in postoperative orthopantomographs which might elevate the risk of osteosynthesis failure. STUDY DESIGN: A total of 136 patients (22 with osteosynthesis failure, 114 without) with 151 mandibular condyle fractures were included in this study. Eight parameters were assessed in postoperative orthopantomographs. RESULTS: The best predictor of osteosynthesis failure was a simplified concept of ramus height. In cases of reduced or normal ramus height, the odds of osteosynthesis failure was significantly (P = .000001) reduced to a 10th. Isolated fractures were significantly more error prone (P = .0009). CONCLUSIONS: Postoperative orthopantomographs depict factors which increase the risk of osteosynthesis failure.