Radiography or Radiology is defined as a branch of medical science that deals with the use of X-rays, radioactive substances and other forms of radiant energy in the diagnosis and treatment of disease.
Radiography and critically X-rays are an integral part of Diagnosis and Treatment planning in each and every branch of dentistry hence Radiography is considered a Dentists “Diagnostic Boon” and the first and main Diagnostic aid.
Sir Wilhelm Conrad Roentgen was the pioneer who discovered X-Rays. And because there was not much known about the ill effects of X-rays Roentgen himself died of Radiation Exposure. Hence Radiation Protection is a very important aspect of Radiology which includes the Operator, Patient and the Dental Staff.
Intra Oral and Extra Oral Radiographic techniques are used in Dentistry.
The intraoral techniques used in dentistry include the bisecting technique, the paralleling technique, and the bite-wing technique.
The dental practitioners who developed these radiographic techniques include Weston Price, a Cleveland dentist, who introduced the bisecting technique in 1904, and Howard Raper, an Indiana University professor, who redefined the original bisecting technique and introduced the bite-wing technique in 1925.
Topics Under Radiography:
- Radiography and its History
- Radiation Physics and Equipment
- Types of Radiographic Films
- Radiation Protection – Operator and Patient
- Radiographic patient considerations and control of infection
- Types of Radiographic Techniques – Priapical, Bitewing, Occlusal, Oblique lateral radiography, Skull and Maxillofacial radiography, Cephalometric Radiography, Tomography
- Diagnosis and Differential Diagnosis considerations using Radiography
- Radiographic Faults
- Radiographic Failures
- Interpretation of Radiographs
- Recent Advancements in Radiographic techniques.
History of Radiography:
- 1838 – German Glass blower – Hein rich Geissler built the first vacuum tube called the Geissler tube.
- 1870 – Johan Willhelm Hittorf used this vacuum tube to study Fluorescence.
- 1870 – Johan Willhelm Hittorf observed that the discharges emitted from the electrode of the tube traveled in straight lines, produced heat,and resulted in a greenish fluorescence.he called these discharges as cathode rays.
- Late 1870 – William Crooks a Chemist discovered that cathode rays were streams of charged particles. These findings and Crooks tube were helpful to Roentgen in Discovering X-rays.
- 1894 – Philip Lenard discovered the property of Cathode rays to penetrate a thin aluminum foil built in the walls of the glass tubes and cause fluorescent screens to glow. He discovered that at a distance of 8cm the fluorescence was seen. It is thought that if Lenard had use more sensitive fluorescent screens he would have discovered X-rays a year before roentgen did.
- 1895 – Sir Wilhelm Conrad Roentgen a Bavarian Physicist discovered the “X-ray”. This is the first step and the sole reason behind Radiography and its application in diagnostic, medical and dental profession. For many years the X-rays were called “Roentgen Rays” and Radiology called “Roentgenlogy”
- 1895 – “First Dental Radiograph” – In the same year the X-rays were discovered. A German dentist Otto Walkhoff made the first Dental Radiograph taken in his mouth using a photographic plate wrapped in black paper and rubber and exposing himself for 25 min to X-rays.
- 1895- W.J. Morton made the first radiograph of the Skull and highlighted the importance of Radiographs in Dentistry.
- 1896 – First whole body radiograph was taken by W.J.Morton using a 3ft by 6ft sheet of film.
- 1896 – C.Edmund Kells the pioneer of Radiology in Dentistry was the first to use a radiograph in practice. He lost his arm due to development of several cancers tumors due to over exposure of X-rays when he used to expose his hand to X-rays for experiments.
- 1901 – William H Rollins a dentist who gave the most important paper on Radiology on the “Dangers involving X-ray use”.
- 1901 – Frank Van Woert was the first person to use a intra oral film for oral radiography.
- 1913 – William D Colidge developed the Coolidge Tube which is the protoptype for all the modern X-ray tubes.
- 1913 – First prewrapped intra oral film was developed by Eastman Kodak company.
- 1923 – AMini Xray tube wasproduced which is theprecursor for dental Xray machines till today.
- 1925 – Howard Raper published theFirst Textbook on Dental Radiology. And also introduced the Bite Wing technique.
- 1947 – Introduction of Long cone Paralleling technique.
Radiography is a very important and integral part of Dentistry and Medicine without which the Diagnosis and Treatment plan will just be guess work. Radiography has certainly changed the whole aspect of Dentistry and its implementations.