Comparative Evaluation of Various Lens and Ring Flash Combination for Intraoral Photography.

BACKGROUND: Extraoral and intraoral dental photographs serve as preoperative records and document the entire treatment. Correctly composed orthodontic photographs are crucial for remote diagnosis and may serve as a bulwark against medicolegal challenges. MATERIALS AND METHODS: In this prospective study, intraoral frontal photographs of patients with ideal occlusion were taken using two types of lenses (EF-S 18-55 mm f/3.5-5.6 IS STM lens (Canon, Tokyo, JP), SP 90 mm F/2.8 MACRO VC lens (Model F017 Tamron, NY, USA)) and two different ring flash systems (Meike FC-100 Macro Ring LED Light (Meike, China), Macro Ring flash Lite YN-14EX (Yongnuo digital, China)). The combination of lens and flash used was grouped into four groups. Twenty-eight intraoral photographs of patients were taken. An image quality assessment survey was distributed among two groups - 50 orthodontists and 50 other dental specialists. RESULTS: The participants were asked to assess all the intraoral images and subjectively score them on a scale of one to ten, with one being very poor and ten being excellent, considering the sharpness, color, brightness, contrast, and overall quality of the image. The general dentists rated the images taken with a 90-mm macro lens and ring flash as the best quality photographs. Images obtained using an 18-55 mm lens and ring LED received significantly lesser scores and were graded good by dentists. CONCLUSION: This combination of lens and flash may prove a valuable investment in the long-term aiding in excellent dental images for diagnosis and treatment monitoring.

WHO respiratory disease survey in children: a serological study

This paper is a report on the first (serologicl) phase of a study organized by WHO in collaboration with the WHO International Reference Centre for Respiratory Virus Diseases other than Influenza in Bethesda, Md., USA, to define the viral etiology of severe respiratory infections in children, particularly in tropical areas. Paired sera from 528 children up to 5 years old admitted to hospital with severe respiratory illness of probable viral etiology were collected in 10 countries and sent frozen to the International Reference Centre, where standard complement-fixation tests were made for the following agents: parainfluenza virus types 1, 2 and 3, influenza virus types A and B, adenoviruses, respiratoy syncytial virus, Mycoplasma pneumoniae, Coxiella burneti and psittacosis-ornithosis. Some 41 percent of paired sera showed rising antibody titres for one or more of these agents, multiple infections being observed in 8 percent. In most of the countries the pattern of life, particularly in the first year of life and in cases of bronchiolitis and pneumonia; the distinction to RS virus infections, they were commoner in older children. Influenza, adenoviruses, and M. pneumoniae were of moderate importance, and C. burneti and the psittacosis-ornithosis agents were relatively rare. This pattern is similar to that which has been observed in temperate climates (AU)