Mouthguard Use and Design in the Prevention of Dental Injuries Amongst Hong Kong's Rugby Community

Mouthguard Use and Design in the Prevention of Dental Injuries Amongst Hong Kong's Rugby Community Philip R H Newsome, BChD, MBA, FDS, FHKAM, MRD, RCS Ed Senior Lecturer, Faculty of Dentistry, University of Hong Kong August 1998 ^% 617.61 </f&t* MS3 if 31SI 1 f H ^i) HON KONG SPORTS DEVELOPMENT BOARD

THE UNIVERSITY OF HONG KONG LIBRARIES Hong Kong Collection gift from Hong Kong Sports Development Board

LAYMAN'S ABSTRACT Injuries to the teeth are almost always permanent and costly. Children playing sport are particularly at risk since it has been reported that as many as 4% of all dental injuries are the result of sporting accidents. While considerable research has been conducted overseas, little research has been performed to examine either the incidence of sports-related dental injuries amongst Hong Kong athletes or the attitudes and behaviour of local athletes with respect to the prevention of these injuries. This project was designed to establish the incidence of sports-related dental injuries amongst players participating in one of Hong Kong's popular contact sports, rugby; determine the attitudes and behaviour of local rugby players in relation to the prevention of such injuries and whether any difference exists between local and expatriate players; and assess currently available protective mouthguards, shop-bought 'boil and bite' types and those custom-made by dentists. Of the players surveyed, 25% reported sustaining a sports-related dental injury at some point in their playing career including loosened, fractured and lost teeth. Other related injuries included soft tissue damage (51%), concussion (35%) and broken jaws (4%). At the time of the survey, 68% of all players were wearing mouthguards while playing rugby. However, for local Chinese players this figure drops to 43% Reasons given for not wearing mouthguards include lack of comfort, a feeling that mouthguards were not necessary and expense Of those players wearing mouthguards slightly more were using shop-bought ones - 38% compared to 3% wearing professionally made mouthguards In a clinical study conducted to compare shop-bought and custom-made mouthguards, the latter were shown to be superior in virtually all aspects, in particular comfort and the degree of protection offered. It is therefore recommended that efforts be made to improve knowledge concerning the dangers of playing without adequate dental protection, in particular amongst local players involved in contact sports

PART ONE Oral-facial Injuries and Sports Mouthguards: A uestionnaire Survey of the Attitudes and Behaviour of Hong Kong Rugby Players Introduction Injuries to the teeth are almost always permanent and are usually costly. The costs involved are not only financial, but may also be psychological, especially whenever a healthy, aesthetic, functional set of teeth is traumatised. As well as damaging the teeth and surrounding structures, violent impact to the oral region may also result in fracture of the facial bones and even neck or brain injury. A number of studies have shown that oral-facial injuries are common occurrences in many sports 1 with rugby players at all levels of the sport being particularly vulnerable 2 ' 3. Sporting accidents are reported to account for 1 to 4 per cent of all dental injuries in children 4 " 6. It is clear that all but the most severe of these injuries can be prevented by the use of correctly designed and fabricated mouthguards - dental injuries have, for example, been all but eliminated in high school and collegiate American football by the mandatory use of mouth protectors 7. Unfortunately, many participants in contact sports continue to play without protection The aim of this study is twofold. Firstly, to explore the attitudes and behaviour of Hong Kong's rugby playing population towards the wearing of mouthguards and secondly, to establish the incidence of oral-facial injuries amongst the same population The game of rugby is particularly popular in Hong Kong, especially since the enormous success of the Hong Kong Rugby World Cup Sevens tournament which took place in 1997. The sport is administered in the SAR by the Hong Kong Rugby Football Union who are keen to develop the game amongst the local Chinese population and amongst women and children. Methods 2,84 17-item self-completion questionnaires (see Appendix) were mailed to all registered members of the Hong Kong Rugby Football Union. A self-addressed stamped envelope was included with each questionnaire, as was an incentive in the form of inclusion in a raffle for sports goods and equipment. Statistical analysis was performed using SPSS for Windows. 359 questionnaires were returned, a response rate of 12.6%. This response rate is rather low in comparison to similar surveys carried out overseas and there are likely to be a number of possible reasons for this - for example, Hong Kong is a transient society and a number of potential respondents may have been out of the SAR at the time of the survey. In addition, many members are retired from the game and a number live overseas and therefore may not have wished to participate in a survey of the Hong Kong scene. Those that did respond may also represent a bias towards those players who either had had dental problems or were mouthguard wearers. In this respect the incidence of mouthguard wear amongst Hong Kong rugby players may in fact be lower than that recorded in the survey.

Respondents Of the respondents, 314 (87.5%) were male and 45 (12.5%) female, with the majority (55% of both men and women) falling into the 25-34 years old age group (Table 1). Table 1: Age/Sex Distribution of Respondents Age Male no. % no. Female % Under 16 yrs 16-24yrs 25-34 yrs 3 5-44 yrs 45 yrs and over 17 5.4 41 13.1 172 54.8 65 2.7 19 6.1 3 15 25 2 6.7 33.3 55.6 4.4 Total (359) 314 1 45 1 While a wide range of nationalities were represented in the study, nearly three-quarters were British followed by 8% who were Hong Kong Chinese (Table 2). Table 2: Nationalities of Respondents Country Total Male Female Percentage of respondents UK HK Chinese USA New Zealand Australia France Canada Japan South Africa India Pacific Islands 72.9 8.4 4.2 3.9 3.6 22 1.4 14 1.4.3.3 72.3 7.3 4.8 4.5 4.1 2.5 1. 1.6 1.3.3.3 77.3 15.9 4.5 2.2 Base 358 314 44 The average age at which the respondents started playing rugby was 13.4 years (std. dev. 6.74) for men and 22 years (std. dev. 6.22) for women.

Mouthguard Wear Despite the fact that over 99% of all the respondents answered 'yes' to the question: 'Do you believe that mouthguards protect your teeth?' only 68% (245 respondents) stated that they were, at the time of the survey, wearing a mouthguard to play rugby. A significant difference was found to exist in this respect between Hong Kong Chinese players and players from overseas, the latter group being more likely to protect their teeth (Table 3). Table 3: Comparison of Player Origin and Mouthguard Wear at Time of Survey Player origin Wearing a mouthguard Not wearing a mouthguard Hong Kong Chinese Overseas Base (all respondents) 5 95 245 Percentage of respondents 15 85 114 Fifty-eight players answered that they had never worn a mouthguard. Reasons given by these players for not wearing a mouthguard were varied and are shown in Table 4. Table 4: Reasons for Not Wearing a Mouthguard Reason Uncomfortable Never had an injury Never thought about it Too expensive Can see no reason to wear one % of non-wearers 95 29 1 7 3 Base: Those who had never worn a mouthguard (58) Note; Multiple responses Amongst these non-wearers, significant differences were seen to exist in terms of player origin and player age (no significant difference was found to exist between male and female players in this respect). Thus older players were significantly more likely to have never worn a mouthguard, compared to younger players (Table 5). 4

Table 5: Comparison of Player Age and History of Mouthguard Wear Under 16 years 16-34 years 35 or over Percentage of respondents Have worn a mouthguard Never worn a mouthguard 1 88 12 67 33 Base (all respondents) 2 253 86 Similarly, Hong Kong Chinese were also more likely to have never worn a mouthguard, compared to players from other countries where awareness concerning prevention of oral-facial injuries in contact sport is perhaps at a more developed stage (Table 6). Table 6: Comparison of Player Origin and History of Mouthguard Wear Hong Kong Chinese Overseas Have worn a mouthguard Never worn a mouthguard Base (all respondents) 7 3 3 Percentage of respondents 85 15 329 Those respondents wearing mouthguards (245 or 68%) were then asked a number of questions relating to their behaviour and experiences with regard to mouthguards. In most cases mouthguard wear began a number of years (mean 3.2; Std. Dev. 6.23) after the player had started playing rugby (Table 7). Table 7: When Started Wearing Mouthguards % Started wearing mouthguard before started playing rugby Started wearing mouthguard at same time as started playing rugby Started wearing mouthguard after started playing rugby Never worn a mouthguard Base: All respondents excluding non responses 5 31 47 17 342

The questionnaire classified mouthguard type into 'dentist-made 1 and 'shop-bought' with an overall majority of players wearing the latter (Table 8). Table 8: Type of Mouthguard Worn at Time of Survey % Shop-bought Dentist-made Not wearing one 38 3 32 Base: All respondents (359) While the sex of the player was not found to be a significant factor in considering the choice of mouthguard type, both age and nationality were. Younger players along with Hong Kong Chinese players were more likely to choose shop-bought as opposed to dentist-made mouthguards (Tables 9 and 1). Table 9: Comparison of Player Age and Type of Mouthguard Worn Type of Mouthguard Under 16 years 16-34 years 35 or over Percentage of mouthguard wearers Shop-bought Dentist-made 67 33 56 44 5 5 Base (mouthguard wearers) 18 177 5 Table 1: Comparison of Player Origin and Type of Mouthguard Worn Hong Kong Chinese Overseas Percentage of mouthguard wearers Shop-bought Dentist-made Base (mouthguard wearers) 1 13 53 47 228

The attitude of mouthguard wearers to the prospect of playing or training without their mouthguard was also investigated (Table 11). Very few would be willing to play without mouthguards, but they were more relaxed about not using them when training. Table 11: Attitudes of Mouthguard Wearers to Mouthguard Use Matches Training Percentage of mouthguard wearers 'I would not participate without wearing my mouthguard 3 'I would be reluctant to participate without wearing my mouthguard' C I would be willing to participate without wearing my mouthguard' Base (mouthguard wearers): 245 59 36 5 24 5 25 A range of problems associated with mouthguards were cited by respondents, particularly by those using the shop-bought versions (Table 12). Table 12: Problems Associated with Different Types of Mouthguard Shop-bought Dentist-made Percentage of all who have used mouthguards at any time Difficulty in speaking Uncomfortable Interferes with breathing Ill-fitting Causes retching, nausea Causes excessive salivating Need to renew frequently Too expensive 47 37 3 27 2 19 15 1 Too expensive Difficulty in speaking Uncomfortable Interferes with breathing Causes retching, nausea Causes excessive salivating Ill-fitting Need to renew frequently 12 1 5 5 4 3 1 1 Base (mouthguard wearers at any time): 31 Note: multiple responses

Three-quarters (77%) of mouthguard wearers currently wearing shop-bought mouthguards had had problems with this type. This suggests that they could be unaware that there may be a better alternative, or were unprepared to pay the extra cost. Of those 18 players wearing dentist-made mouthguards, half (48%) reported having had problems with shop-bought mouthguards in the past. For these players a nil response most likely simply reflects that they have never worn a shop-bought mouthguard in the past - it does not mean that half these respondents had worn shop-bought mouthguards and found no problems with them. For those respondents currently using shop-bought mouthguards the major problem with dentistmade mouthguards, mentioned by 12 out of 13 who reported problems, was one of cost (again a nil response may simply reflect that they have never tried a dentist-made mouthguard, not that they have tried one and found no problems). For those players currently wearing custom-made mouthguards the cost seemed less of an issue, mentioned by only 16 out of 44 who reported problems with them. Dental Injuries Finally, questions were asked about any oral-facial injuries received while playing or training for rugby, and specifically about any dental injuries they received (Table 13). For 149 players, their injuries were sufficiently serious for them to seek medical or dental care. Of the 88 respondents reporting dental injuries, 26 continued to play rugby without wearing a mouthguard. These included four out of the six players suffering avulsions (teeth completely detached from the jaw). Oral-facial injuries in sports other than rugby were reported by 172 respondents (48%) - indicating that other sports can also be hazardous to dental health! Table 13: Incidence of Rugby-related Oral-facial Injuries Received Oral-facial Injuries Generally Nature of Dental Injuries Percentage of all respondents Bruising of face Damage to lips, cheeks or tongue Concussion Damage to teeth Fractured jaw 65 51 35 25 4 Tooth/teeth loosened but still in place Tooth/teeth fractured Tooth/teeth avulsed* 16 12 2 Base (all respondents): 359 Note: multiple responses ^Completely detached from the jaw

PART TWO A Clinical Comparison of Custom-made Laminated Mouthguards with Self-adapted Designs Aims Given both the lack of information concerning the use of inouthguards by the local Chinese population and also the increased vulnerability to injury of young athletes, the aim of this study was to compare user acceptability in young Chinese athletes of custom-made laminated mouthguards with self-adapted 'boil and bite' types bought over the counter. Methods Sixty Chinese males, aged between 12 and 18 years of age, were selected from the patient pool of the Prince Philip Dental Hospital, Hong Kong. All those selected took part in some form of athletic activity. Each player was provided with: a) a custom-made mouthguard made from two layers (2mm and 3mm respectively) of polyvinyl acetate polyethylene (EVA) material on a model made from impressions of the patient's mouth; and b) a self-adapting mouthguard purchased at a local sports shop. Full instructions on how to use the two types of mouthguard were provided to each patient. In particular, participants were asked to mould the shop-bought mouthguard as directed in the instructions provided by the manufacturer. At the initial impression visit participants were asked to fill out a questionnaire concerning their experience with mouthguards and sports injuries. Patients were asked to wear the custom-made mouthguard initially for a period of three weeks, after which time it was exchanged for the self-adapted type. After wearing both designs of mouthguards, patients were given a second questionnaire to evaluate comfort and wearability factors. Respondents All but two of the sixty participants were born and raised in Hong Kong, with 44 (73%) attending Chinese schools and 16 (27%) attending English-language schools. All 6 participants were active in sports sessions both in and out of school time (Table 14), Just over half the participants 34 (57%) said they knew what a mouthguard was, yet when asked if they believed that mouthguards would offer some protection for their teeth all but two (97%) responded c yes'. Prior to the study, only two of the respondents said that they had ever worn a mouthguard. The following reasons were given for not wearing one (Table 15).

Table 14: Sports Played by Survey Participants Sport Basketball Soccer Racquetball Martial arts Swimming Table tennis Gymnastics Rugby Base: (all respondents) 6 % 63 57 2 1 1 7 7 3 Table 15: Reasons for Not Using Mouthguards Reason Never thought about it Can see no reason to wear one Never had an injury Too expensive Base: 58 % 62 24 14 7 During the study 12 of the participants (2%) sustained injuries to the head and neck. These injuries comprised minor soft tissue lacerations and bruising of the face. One had a deciduous tooth knocked out completely during play; no medical or dental advice was sought and he was not wearing a mouthguard at the time. Nearly half (47%) of the participants reported problems with the custom-made mouthguards while 34 (57%) noted difficulties with the self-adapted design. Six participants (1%) experienced problems trying to mould the self-adapted mouthguard, found difficulty in following the instructions provided and found that it took too long to boil the mouthguards resulting in serious distortion of the material The only statistically significant differences observed between custom-made and self-adapted mouthguards was in terms of retention and cost with the custom-made version perceived as being more retentive but more expensive. Around twice as many participants 38 (63%) said that, overall they would prefer to wear a custom-made mouthguard rather than a self-adapted type, compared to 2 (33%) who preferred the latter design. 1

CONCLUSIONS Both the initial questionnaire survey and the clinical study clearly show there to be a significant lack of awareness amongst Hong Kong's Chinese athletes of the ability of mouthguards to prevent oral-facial injuries. This is in spite of the well-documented advantages of protective mouthguards. Of the mouthguards currently available in Hong Kong, athletes tend to prefer the custom-made variety but may be put off using them because of the perceived high cost. Strategic Recommendations Although this research study focused on Hong Kong's rugby community it is felt strongly that the following recommendations apply just as much to all contact sports currently being played in Hong Kong, including basketball, field hockey, ice hockey, lacrosse and the various martial art sports. Participation in contact sports clearly places teeth at risk and yet despite there being a general awareness that a mouthguard can prevent dental injuries, many athletes still choose not to wear one. The first recommendation therefore is to: 1 Raise awareness amongst athletes Changing attitudes and behaviour is notoriously difficult and while some change may be effected by the distribution to athletes of educational literature (such as brochures and posters) it is strongly felt that other people should be included in the educational process. The second recommendation therefore is to: 2 Raise awareness amongst coaches, teachers and parents It may be possible through the use of literature and seminars to convince these parties of the various benefits of wearing mouthguards. For example, coaches and teachers should see greater player confidence and better performance if correctly designed mouthguards are worn, and less time out of the game through injury. Parents and teachers should be informed of the risk their children are taking by playing contact sports without adequate dental protection. A further step in this direction would be to: 3 Enforce the wearing of mouthguards for all children playing contact sports The wearing of mouthguards has been mandatory in US school and college football for over a decade with the consequence that dental injuries have all but disappeared from the game. One of the most positive steps that could be taken would be to ask schools and sports associations to make the wearing of mouthguards mandatory for all participants under the age of, say, eighteen years. This is supposed to be the situation in mini-rugby but anecdotal evidence suggests that this rule is not being enforced by coaches and referees. The next two recommendations are aimed at improving general awareness of the benefits of mouthguards: 11

4 Create role models who promote the use of mouthguards In the US it is common for top athletes such as Joe Montana and John Elway to act as role models. Attempts should be made for appropriate local equivalents to be found. 5 Enlist the help of commercial and professional bodies to promote the use of mouthguards Companies who have an interest in promoting dental health, for example toothpaste companies, should be contacted with a view to sponsoring educational material aimed at raising awareness. Similarly, professional associations such as the Hong Kong Dental Association should be approached to discuss the possibility of establishing mouthguard provision programmes. The Hong Kong Dental Association should also be encouraged to inform its members of the need to inform and educate patients who play contact sports. It is also important to ensure that correctly designed and produced custom-made mouthguards are available in Hong Kong at a reasonable price 8. It is therefore necessary to: 6 Train local dental laboratories to produce correctly designed, laminated mouthguards At the time of writing these mouthguards are only available from a small number of laboratories and this deficiency needs to be corrected. Consideration should also be given to the introduction of legislation (as is happening in the European Community 9 and Australia 1 ) demanding that all mouthguards conform to certain basic requirements. 12

References 1 Sane J and Ylipaavalniemi P Dental trauma in contact team sports. Endod Dent Traiimatol, 1988; 4: 164-169. 2 Chapman P J Orofacial injuries and international rugby players 3 attitudes to mouthguards. Br JMed, 199; 24, 156-158. 3 Chapman P J and Nasser B P Prevalence of orofacial injuries and use of mouthguards in high school rugby union. AitstDentJ, 1996; 41: 252-255 4 Rodd H D and Chesham D J Sports-related oral injury and mouthguard use among Sheffield schoolchildren. Community Dental Health, 1997; 14: 25-3. 5 Uji T and Teramoto T Occurrence of traumatic injuries in the oromaxillary region of children in a Japanese Prefecture. Endod Dent Tranmatol, 1988; 4: 63-69. 6 Hayrinen-Immonen R, Sane J 5 Perkki K and Malstrom M A six year follow up study of sportsrelated dental injuries in children and adolescents. Endod Dent Traumatol, 199; 6: 28-212. 7 Padilla R and Balikov S Sports dentistry: Coming of age in the 9s. Calif Dent Assoc J, 1993; 21: 27-36. 8 While 'boil and bite' mouthguards are available from sports goods shops usually at less than $5, a typical price range for custom-made mouthguards from dental practices is around $5-2, (prices at March 1999). 9 Mouthguard manufacturers in the EC must comply with Personal Protective Equipment legislation. 1 Australian guidelines can be found in: National Health and Medical Research Council Football Injuries of the Head and Neck. Canberra: Australian Government Publishing Service, 1994. 13

APPENDIX University of Hong Kong Faculty of Dentistry Hong Kong Mouthguard Survey This survey is being conducted by the Faculty of Dentistry to Increase our understanding of the use of mouthguards amongst male and female rugby players in Hong Kong. The results will help us to advise dentists in providing comfortable and efficient mouthguards. FIRST SOME FACTS ABOUT YOU 1. Sex Male Female 2. Age group Under 16 16-24 25-34 35-44 45 or over 3. Nationality 4. Age when you first started playing rugby years old 5. Club Team (eg 1 st, 2 nd etc) 6. Principal team position (eg forward, back) NOW SOME UESTONS ABOUT MOUTHGUARDS 7. Do you believe that mouthguards protect your teeth? Yes No 8. Do you currently wear a mouthguard? Yes No If no, why not? Never thought about it Can't see a reason to wear one Never had an injury Too expensive Uncomfortable Other reasons 14

9. How old were you when you first started wearing a mouthguard? _ years old I have never worn a mouthguard (please go directly to 13) 1. Which type of mouthguard do you wear? Shop-bought mouthguard Dentist-made mouthguard Of 11. How would you feel about playing or training without wearing your mouthguard? Match Training (involving contact) I would not play without it or I would be reluctant to play without it or I would be willing to play without it 12. Have you ever experienced any problems with your present, or previous, mouthguards, and if so, what were these problems? Yes No Shop-bought mouthguard Dentist-made mouthguard Interferes with breathing Uncomfortable Feels loose Causes retching, nausea Difficult to speak Excessive salivating Need to renew frequently fitly Too expensive Any other problems? 15

NOW A FEW UESTIONS ABOUT ANY INJURIES YOU HAVE SUFFERED WHILE PLAYING RUGBY 13. Have you ever had injuries that involved any of the following during a rugby match or training? Your teeth Your lips, cheeks or tongue Bruising of the face Concussion Fractured jaw 14. In the case of dental injury, did any of the following happen to your tooth or teeth? Completely knocked out of the jaw Loosened, but still in place Fractured j 15. Did you need to seek medical or dental advice for any of the injuries? Yes No 16. Were you wearing a mouthguard when your teeth were damaged? Yes... No 17. Have you ever sustained any injuries to your mouth or face during any other sporting activities? THANK YOU FOR TAKING THE TIME TO COMPLETE THIS UESTIONNAIRE - PLEASE MAKE SURE YOU HAVEN'T OMITTED TO ANSWER ANY UESTIONS 16 "NO HOC'

XlWflflMES HKP 617.61 N53 Newsome, Philip R. H. Mouthguard use and design in the prevention of dental injuries amongst Hong Kong's rucbv community Date Due **5 m 2J I