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Laboratory research in dentistry and dental education use extracted human teeth as a model for simulation for ex vivo procedures. Human-borne tissues are the first choice of material for bond strength assessment. To obtain comparable results in dental material tests and to ensure microbiological safety, specimens must be stored under specific, uniform conditions. The aim of this paper was to present the contemporary view and recommendations on preserving extracted human teeth. The antimicrobial properties of the storage medium are a crucial aspect, as extracted teeth pose a risk of cross-infection. A classification of different methods (using solutions and otherwise) is presented and their sterilizing efficiency is compared based on the literature. The emphasis is put on the interaction between the storage conditions and the substrate. Tooth specimens should be biologically safe and have normal mechanical properties. The sterilizing process must be neutral for the enamel and dentin microstructure, because even a minor change can affect the adhesive bonding. Autoclave sterilization and storage in 10% formalin solution are widespread and reliable methods, although they do have their disadvantages. There is a need for further investigation in order to establish uniform recommendations on preparing and preserving extracted human teeth used for research purposes.

The technique described as indirect bonding is an alternative to the conventional intraoral method of bracket placement. The appliance position is planned and fixed on a plaster model and then transferred into the oral cavity. Indirect bonding is a precise and time-saving technique of bracket placement, growing in popularity in recent years. It provides a combination of great precision with time efficiency. The fundaments of the indirect bonding technique are presented here. From the first clinical trial conducted almost fifty years ago, the method has evolved; the progress that has been made is described. Modern technologies involving computer scanning and manufacturing have led to great precision in bracket placement. Digital innovations such as rapid prototyping and stereolithography open up a new avenue of research and represent the next steps in indirect technique development. Individual 3D transfers are convenient in difficult clinical cases and can improve the effectiveness of the procedure, reduce the number of technical stages and reduce total chairside time. This paper also summarizes the advancement in adhesive materials, including an overview of advantages and disadvantages of different types of bonding resins and of the mean shear bond strength (SBS) achieved in the indirect procedure.

Photodynamic bronchoscopy with inhalation of 5-ALA is a relatively safe diagnostic method. The main disadvantage is high percentage of false positive results. Nevertheless, we believe, that it may be a useful adjunct to conventional diagnostic modes, especially in the detection of early lesions in patients operated due to cancer (stump control and detection of metachronous lesions) and those prepared for operation (synchronous lesions and detection of infiltration margins). However all suspected lesions must be verified by histo-pathological examination.

Multiplex FISH (UroVysion), Comparative Genomic Hybridization (CGH), and Multitemperature Single-Strand Conformation Polymorphism (MSSCP) were applied for non-invasive diagnosis and prognosis of bladder cancer. The UroVysion test was positive in 80% of patients with pT1 and in 100% of patients with either pT2 or pT3 tumours. Tumours with pT3T4 stages were characterized by high numbers of chromosomal imbalances, detected by CGH. The mutation of the p53 gene was detected in 16% of patients, but only in those with pT2 or pT3 tumours.