The aim was to report the distribution, frequency and aetiology of jaw fractures in patients treated at the University Hospital, Malmö, 1993-2003 and to compare two previous studies from 1952-1962 and 1975-1985. In 1993-2003, 461 patients, 137 women (mean age 42 years; range 15-82) and 324 men (mean age 28 years; range 17-59) were diagnosed and treated. Women were significantly older than men (P<0.001). The most frequent cause of jaw fractures was falls in women (45%). In men, interpersonal violence (46%) was most common followed by road traffic accidents (RTAs) (24%) mostly involving bicycles (14%). The frequency of falls in women and men was significantly different (P<0.001) as was the difference between violence in men and women (P<0.001). The proportion of fractures caused by RTAs was significantly higher in 1952-1962 than in 1993-2003 (P<0.001). There was a significant increase in the proportion of fractures caused by violence between the two studies (P=0.007). In 1993-2003 the proportion of fractures in women due to falls was significantly higher than in 1952-1962 (P=0.006). Violence has replaced RTAs as the main cause for jaw fractures in men; for women falling is the commonest cause.