Presbyopia and the dentist: the effect of age on clinical vision.

Vision is extremely important in dentistry where many clinical tasks requiring fine discrimination are performed. Presbyopia, an inability to focus sharply on near objects, affects all dentists in the later years of their practising lives and may have adverse effects on the practice of dentistry. This study examined the visual acuity of 172 practising dentists using a reduced Snellen chart imaged at 25 cm and 33 cm. Twenty-seven per cent failed the near vision test, having acuity of less than 6/9 at 25 cm, while 18 per cent had acuity of less than 6/7.5 at 33 cm; 96 per cent of those who failed at 25 cm and 93.5 per cent of those who failed at 35 cm were 45 years of age or more. Working distance (operating distance) was found to be significantly greater in dentists over the age of 45 than in a group of undergraduate dental students. No statistically significant relationship between visual acuity and working distance could be demonstrated. Regular examinations by qualified personnel are essential for dentists who should have their eyes checked every 2 years after the age of 40. Dentists should discuss their specific requirements for the practice of dentistry with their eye-care specialist. A suggested minimum standard of visual acuity for practising dentists is 6/7.5 at 33 cm.