Radiography Radiography • Roentgen tube – x- ray tube: Cathode – anode – tension Catode (heated) - electrons –against anode – brake - x ray radiation originates Radiography • Imaging method completing clinical examination of patients Radiography Principle: X- rays going through various materials (tissues) are absorbed – image on the film (a special suspension AgBr – silver bromide) or digital receptors Rigid CCD Digital Sensor Sirona Dental Systems, LLC Digital Phosphor Plate Air Technique, Inc. F-Speed Dental Film Kodak Dental Systems Roentgen tube X ray tube Anode Cathode wolfram (tungsten) filament inside (heated – brought to white heat) Focus – made of wolfram Extraoral and intraoral radiography • Extraoral: The film is placed outside of oral cavity - OPG (orthopantomography) - Teleradiography - Special projections of a skull (posteriorly – anteriorly) - Half axial - Side projection (TMJ,mandible) - CT Extraoral and intraoral radiography Intraoral – the film is placed in the oral cavity – a special x-ray apparatus. - Teeth - Alveolar bone - Periodontal space - Fillings - Caries - Level of endodontic treatment OPG Side Posteriorly-anteriorly Posteriorly-anteriorly Half axial CT OPG Half axial Posteriorly-anteriorly Side CT CT CT, 3D possibility Intraoral radiography Film or recepotor placed in oral cavity Special apparatus - Teeth - Alveolar bone - Periodontal space - Fillings - Caries - Impacted teeth - Level of endodontic treatment Position of the tubus • In vertical plane • In horizontal plane In vertical plane Paralleling technique Film or receptor in a special holder Parallel to long axis of teeth If paralleling technique is not possible use the bisecting angle technique Bisecting angle technique – isometric radiogram The x-ray beam Angle between the beam and axis of the angle The long axis of the tooth The tooth The angle betwen the long axis of the tootn and the film Film Alveolar bone and surrounding tissues The axis of the angle Hypometric and hypermetric picture Central beam goes perpendiculary on the tooth Hypermetric picture – the picture is bigger – central beam goes perpendiculary to the film paprsek goes perpendiculary to the film. Hypometric – the picture is smaller The tubus can have various position • Apical projection: the central beam goes through the apex area • Periodontal projection: the central beam goes through the uper third of the root • Coronal projection: the central beam goes through the crown. Marginal – limbal position (projection) Apical position - projection In horizontal plane Orthoradial and excentric projection • Orthoradial – the central beam goes parallel to interdental septa • Excentric– the central beam goes from distal or mesial side. (Useful for endodontics or impacted teeth esp. canine) Bitewing Film or receptor is placed in a special holder, patient bites into The central beam goes parallel to interdental septa Crowns of teeth are well seen – good for early diagnosis of dental caries in posterior area Principle of imaging • Irradiation is absorbed in various materials esp. in hard tissues. Accc to amount of absorbed irradiation radioopacity or radiolucency can be seen. Radiolucency – dark Radioopacity - white • Rtg status LR i.o. LR LR OPG radioopacity radiolucency CBCT CBCT – cone beam computer tomography Definujte zápatí – název prezentace nebo pracoviště39 CBCT Source and detector trotate CBCT – cone beam computer tomography Definujte zápatí – název prezentace nebo pracoviště40 • High diagnostic effect • Endodontics • Omplantology • Surgery • Traumatology Radiogram before the treatment Radiogram aftre the treatment Radiogram 6 month post.op. Radiogram with inserted root canal instrument