{'fraction_non_alphanumeric': 0.011608623548922056, 'fraction_numerical': 0.0, 'mean_word_length': 5.637362637362638, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Progressive addition lenses for dentists with presbyopia

Dentistry has unique visual demands. While clinical tasks requiring fine discrimination are routinely performed, dentists also need good intermediate vision in their working environment. A study by the authors has shown that many older dentists have undercorrected presbyopia and, as a consequence, use a working distance which is significantly longer that that used by dental students and younger practitioners. A modified regular progressive lens fitted to a lookover frame is described which enables presbyopic dentists to be fully corrected.