Almost four out of ten professional footballers have cavities, while one in 20 has irreversible gum disease.
Others suffer infections, while many experience regular toothache, found the study, published in the British Journal of Sports Medicine. This poor level of dental health affects footballers’ performance and wellbeing, and the sport “urgently” needs to promote better dental care.
The dental health of footballers appears to be worse than for the general population.
Many footballers drink sports drinks several times a week, although evidence is “unclear” on whether this is to blame.
The study involved 187 footballers from eight clubs - Hull, Manchester United, Southampton, Swansea City, West Ham, Brighton and Hove Albion, Cardiff and Sheffield United.
Six dentists checked the tooth and gum health of every player - equivalent to more than 90 per cent of each senior squad - and each footballer was asked about the impact of dental health on their personal and professional lives.
Almost three-quarters of players (73 per cent) had been to the dentist within the past 12 months and 22 per cent reported a history of trauma to their teeth or face due to the sport.
Some 64 per cent of players said they drank sports drinks at least three times per week, while 5 per cent used tobacco, mainly smokeless or chewing tobacco.
Researchers found that 37 per cent of the footballers had at least one tooth affected by decay while 77 per cent had needed fillings, with some needing more than five.
Overall, 84 per cent of all footballers had at least one decayed or filled tooth.
Dental “erosion”, where the tooth is worn away by acid, was present in 53 per cent of footballers, while 77 per cent of footballers had half of their mouth affected by gingivitis (inflammation of the gums). In 5 per cent of footballers, this was moderate to severe and irreversible.
Some 8 per cent of footballers had at least one ulcer, abscess or open sore, while one in 10 had regular toothache and 16 per cent experienced pain in their mouths. Over a quarter (27 per cent) had sensitivity to hot or cold drinks.
More than 45 per cent of footballers said they were “bothered” by their oral health, with 20 per cent reporting an impact on their quality of life and 7 per cent reporting an impact on training or performance.
The researchers, including from University College London, said several things contribute to poor dental health, including food and drink and how much emphasis is placed on oral health in sport.
Some teams had worse teeth than others, suggesting there is a role for preventing tooth decay and introducing formal screening in clubs, they said.
“Few teams integrate oral health promotion within overall medical care, and there is therefore lack of ongoing support and reinforcement of this health area for the athletes,” they wrote.
“Oral health of professional footballers is poor, and this impacts on wellbeing and performance. Successful strategies to promote oral health within professional football are urgently needed.
“Furthermore, this study provides strong evidence to support oral health screening within professional football.”
The experts stressed the “relationship between sports drinks and dental erosion remains unclear”.
One review, which was just on children, found no link, although another study on 3,000 people found drinking sports drinks was linked to tooth decay.
The footballers were typically aged 24, though they ranged in age from 18 to 39.