ISE34/20-21

• Tooth decay, or dental caries, is one of the most prevalent chronic diseases for children worldwide, with more than 530 million children suffering from decay of their primary teeth in 2019.^{1Legend symbol denoting See World Health Organization (2020).} Untreated dental caries can cause pain and infections which may affect a child's growing permanent teeth, general health and quality of life. Fortunately, tooth decay can be prevented with proper toothbrushing and flossing, reduced sugar intake, and preventive dental treatments such as the use of fluoride^{2Legend symbol denoting Fluoride is a natural mineral which inhibits or reverses the initiation and progression of dental caries. It can be applied topically and systemically. Topical fluoride is the direct application of fluoride onto the teeth in the form of toothpastes, gels or mouth rinses, strengthening teeth that are in the mouth. Systemic fluoride is ingested through food and water, and becomes incorporated into forming tooth structures. It can be delivered through community water fluoridation and dietary fluoride supplements in the forms of tablets and drops. See National Health Service (2021).}.
• In Hong Kong, children aged under 15 were among the group with the highest utilization rate of dental care services, at 55% in 2018-2019 versus 40% for the entire population.^{3Legend symbol denoting See Census and Statistics Department (2019). The Research Office of Legislative Council Secretariat also issued a Statistical Highlights on "Dental Care Services for the Elderly" in October 2021, providing an update on the recent development of elderly persons' usage of dental care services in Hong Kong.} The existing School Dental Care Service ("SDCS") in Hong Kong provided by the Department of Health ("DH") offers decent coverage mainly to primary school students, yet preschool children^{4Legend symbol denoting Preschool children generally refer to children at or under five years of age, who may be attending kindergartens or nurseries.} are not entitled to this subsidized dental service. With the apparent gap in SDCS services, the overall caries prevalence of preschool children has shown no significant improvement over the last two decades or so even when the oral health of primary students has steadily improved over the years^{5Legend symbol denoting See Chen et al. (2019).}. Meanwhile, some parents have been reluctant to bring their preschool children to seek dental treatment, due to time/cost concerns as well as the misconception that dental treatment on primary teeth may not be of urgency^{6Legend symbol denoting Some parents mistakenly believe that, since primary teeth will eventually get loose and fall, their children do not need dental treatment when experiencing oral symptoms in their primary dentition.}. As a recent survey conducted in 2016 found that over 55% of five-year-old children are suffering from dental caries, the issue warrants closer examination.
• This issue of Essentials begins with an overview of DH's dental care services for children in Hong Kong, highlighting the divergence of service and experience between preschool and primary children. This is followed by a discussion of the oral health efforts in other developed places such as Scotland of the United Kingdom ("UK"), Singapore and Australia, particularly in widening the scope and coverage of oral health programmes, with a view to enhancing service accessibility and/or providing financial support so that children can access dental care in a timelier manner.

Child dental care services in Hong Kong

• In Hong Kong, the Government's policy on dental care seeks to raise public awareness of oral hygiene and to encourage proper oral health habits for prevention of dental diseases. Besides promotion and education, the Government has focused its effort on providing (a) emergency dental services for the general public;^{7Legend symbol denoting DH provides free emergency dental service to the general public through designated sessions in 11 government dental clinics. The services are restricted to treatment of acute dental diseases, e.g. prescription for pain relief, treatment of oral abscesses and teeth extraction (one tooth per visit). After emergency treatment, the patients need to seek follow-up treatment from their own dentists.} and (b) dental care for targeted groups such as primary school students, elderly receiving long-term care services or with financial difficulties, and people with disabilities.^{8Legend symbol denoting As explained by the Government, it is rather difficult to provide comprehensive dental services for the public due to the substantial financial resources involved. See Legislative Council Secretariat (2020).} People who are not covered by the above scope of services generally have to seek treatment from dentists in the private sector.
• As to public dental services for children, the Government has launched SDCS in September 1980 to provide regular dental examinations and basic dental treatment for primary school children. The programme initially started with Primary 1 students and has been extended to all primary school children since 1987. Reflecting the favourable response from parents and schools to the provision of preventive dental care, the share of primary school population participating in SDCS rose from around 66% in 1987 to 95% in 2011, and has hovered at such a high ratio since then. In 2020, some 359 500 or 96% of primary school children participated in SDCS. At present, apart from serving all primary school students, SDCS also covers students under the age of 18 with intellectual and/or physical disabilities studying in special schools.
• Primary school students joining SDCS can receive annual dental services covering basic restorative and preventive treatment (e.g. scaling and filling). Where necessary, tooth extraction and more complex dental treatment are also provided. SDCS also provides oral health education so that students understand the importance of maintaining good oral hygiene and preventive care at an early stage. With substantial subsidies from the Government, the annual fee for each SDCS participant is set at only HK$30 with services mainly delivered at nine school dental clinics by DH's dental therapists^{9Legend symbol denoting Dental Therapists are dental personnel who have completed three years of professional training and are appointed by DH. Their main responsibilities are to provide basic dental treatments such as scaling and filling to children.} under the supervision of dental surgeons.^{10Legend symbol denoting As at 1 February 2021, the establishment of SDCS included 32 dentists, 269 dental therapists, as well as 42 dental surgery assistants deployed to assist dentists in the treatment of patients. See Food and Health Bureau (2021).}
• Meanwhile, primary schools across Hong Kong may choose to participate in the school-based "Bright Smiles Campus", an oral health promotion programme to empower their students to improve the cleanliness of their teeth. To sustain the efforts on oral hygiene awareness built up in students' primary school years, DH has launched a similar school-based programme – "Teens Teeth" – to teach Form 1 students to develop good oral health habits. Both programmes are based on a peer-led approach (i.e. train-the-trainers) whereby senior grade students are nominated to receive training arranged by DH. After attending the training sessions, these students return to their schools as "ambassadors" or "peer leaders"^{11Legend symbol denoting Students trainers are known as "Bright Smiles Ambassadors" under the Bright Smiles Campus programme and "Peer Leaders" under the "Teens Teeth" programme.} to pass on their acquired skills and knowledge on oral hygiene to junior schoolmates.^{12Legend symbol denoting According to Food and Health Bureau (2020), a total of 91 primary schools have participated in the "Bright Smiles Campus" Programme. As for secondary schools, there is no information in the public domain regarding their participation figures in the '"Teens Teeth" Programme.}
• For preschool children, the "Brighter Smiles for the New Generation" programme was launched in 1993 to promote good toothbrushing and smart diet habits amongst children below six years old in kindergartens and nurseries through a variety of home-school oral health care activities.^{13Legend symbol denoting Under the Programme, the Oral Health Education Division of DH provides the participating schools with various oral health education materials. With these materials, the schools will designate a 12-week period to conduct a school-wide oral care activity. The students are encouraged by the teachers to watch the oral care animation and follow the activity details shown in the oral care animation. In order to reduce the risk of tooth decay, parents are also asked to (a) remind their children to brush their teeth with children's fluoride toothpaste at home; (b) provide them with supplementary toothbrushing daily; and (c) help them establish a smart dietary habit.} As at March 2020, around 68% of kindergartens in Hong Kong have participated in the Programme.^{14Legend symbol denoting See Food and Health Bureau (2020).} Furthermore, DH administers "Brighter Smiles Playland" specifically for four-year-old children to help them learn good oral care habits through interactive games and activities. Yet, as mentioned above, preschool children in Hong Kong are not entitled to join SDCS and enjoy the subsidized dental check-up and treatment.

Dental caries experience of children

• The introduction of SDCS has been impactful in improving access to appropriate dental services and reducing tooth decay for primary school children in Hong Kong^{15Legend symbol denoting See Mathu-Muju et al. (2013).}. According to the findings of previous oral health surveys, there has been a sharp decline in the prevalence of permanent tooth decay for primary school children between 1980 and 2011. In 1980, when SDCS was first launched, more than half (57%) of children aged between 9 and 11 had at least one permanent tooth with caries. The mean number of decayed, missing or filled permanent teeth ("DMFT")^{16Legend symbol denoting Teeth with untreated decay are known as decayed teeth, teeth that were removed due to decay are referred to as missing teeth, whereas teeth with decay in the past but already been repaired by restorative procedures are known as filled teeth. The convention is to use DMFT for decay experience of permanent teeth, and dmft for decay experience in primary teeth.} was 1.5, where more than 90% of carious teeth were untreated.^{17Legend symbol denoting See Lee et al. (2016).} In 2001, when the Government conducted the first territory-wide decennial Oral Health Survey^{18Legend symbol denoting DH has since 2001 conducted territory-wide Oral Health Survey ("OHS") every 10 years to evaluate the oral health of representative groups among the population. DH is conducting the 2021 OHS which would evaluate, among others, five-year-old children for the development of their primary dentition, as well as the 12-year-old children for their transition to permanent dentition.}, only 38% of children aged 12 had experienced decay in their permanent teeth, recording a mean DMFT of 0.8. In the latest 2011 Oral Health Survey, the caries prevalence rate and mean DMFT eased further to 23% and 0.4 respectively.
• On the other hand, the oral health status of preschool children, who have yet to benefit from the SDCS, remains unsatisfactory vis-à-vis primary school students. According to several epidemiological studies conducted over the past two decades, the prevalence of dental caries of five-year-old children ranged from 48% to 56%, and the mean number of decayed, missing or filled primary teeth ("dmft") ranged from 1.8 to 2.7. Unsurprisingly, according to a study conducted by the University of Hong Kong in 2018, the unsatisfactory situation may be due to the deficiencies of the current oral healthcare system in delivering accessible preventive and curative dental services to preschool children in Hong Kong^{19Legend symbol denoting See Chen et al. (2019).}.
• More specifically, preschool children from low-income families have a higher tendency to experience dental caries, as private dental services are less affordable for them.^{20Legend symbol denoting See, for example, Chu et al. (2009), Chen et al. (2019) and Duangthip et al. (2019).} A recent study published in 2019^{21Legend symbol denoting See Duangthip et al. (2019).} indicated that preschool children from low-income families had a markedly higher caries prevalence rate (59.4%) than those from high-income families (29.1%). Furthermore, preschool children from underprivileged backgrounds also recorded less favourable mean dmft scores, at 2.8 for the lowest-income group as compared to 1.1 for the highest-income group.^{22Legend symbol denoting The preschool children were divided into three groups according to their corresponding level of family income, namely those with family income (a) less than HK$15,000; (b) between HK$15,001 and HK$30,000; and (c) more than HK$30,000.}
• The high prevalence of tooth decay among preschool children, particularly those from low-income families, is worthy of concern. Untreated cavities can cause pain and infections that may lead to problems with eating, speaking and learning. Advanced caries might progress into the tooth pulp to eventually form dental abscesses. However, some parents of preschool children might be reluctant to bring their children to visit private dentists due to time/cost concerns. Meanwhile, government clinics would only provide emergency treatment such as pain relief and teeth extraction, and it may be difficult to secure the limited number of discs allocated for such public dental services. Yet the need for early intervention is vital. If a primary tooth is lost early due to delayed treatment, the permanent tooth loses its guide and can drift or erupt incorrectly into the mouth. Concerns over the potential risks of dental caries in children have given rise to discussions as to whether more targeted and timely preventive measures should be introduced in the kindergarten stage.
• Against the limited subsidized dental care for preschool children, some non-governmental organizations have launched short-term community oral health programmes, including free oral examination and topical fluoride treatment for preschool children^{23Legend symbol denoting For instance, the Faculty of Dentistry of the University of Hong Kong launched a two-year pilot kindergarten-based outreach oral health care programme in 2008. Later, this programme was scaled up and continued providing dental screening and fluoride treatment for caries control in kindergartens from 2010 to 2019. In 2019, with a three year funding from the Hong Kong Jockey Club Charities Trust, the Faculty of Dentistry expanded the scope of the project to cover over 180 000 kindergarten children starting from the 2020-2021 academic year. See Chai et al. (2020) and The University of Hong Kong (2020).}. However, these initiatives are often dependent on funding from charities and/or the private sector, so they may be haphazard in scope/coverage as well as duration of availability.

Child dental care services in overseas places

• With dental caries largely preventable, many other developed places have sought to improve their child oral health services for early identification of risk factors and implementation of preventive and curative measures at a young age. Scotland has been delivering supervised toothbrushing and preventive dental treatment to preschool children since 2011, whereas Singapore has provided free school dental services for children from preschool in addition to those in primary and secondary school levels. On the other hand, Australia has been providing dental vouchers to children from low income families since 2008, which serve as a safety net for needy children, regardless of age, to access basic dental care in a timely manner.

Scotland

• In Scotland, early childhood caries^{24Legend symbol denoting Early childhood caries refers to the presence of one or more decayed, missing or filled primary tooth (dmft of one or above) in preschool children.} was very common during the early 2000s when over 55% of five-year-old children were found to suffer from tooth decay.^{25Legend symbol denoting See Scottish Executive (2002).} The situation was attributed to high sugar intake and poor oral hygiene among children, as well as to the limited efficacy of oral health education programmes at schools. In response, the Scottish government began pivoting towards a prevention-based approach to improve the oral health of preschool children. This has ushered in a supervised toothbrushing programme in school settings in 2001, followed by the provision of preventive child dental care services in local community settings in 2006. By 2011, these two components of dental care services have been subsumed under the Scotland-wide and multi-faceted oral health improvement programme known as Childsmile.
• The daily supervised toothbrushing delivered to three- and four-year-old children across all nurseries in Scotland remains a key element of Childsmile. Toothbrushing sessions are led by teachers and staff at nurseries who supervise and assist students to brush their teeth. A "train-the-trainer" programme^{26Legend symbol denoting A designated lead from each nursery receives training from NHS Scotland, and in turn trains the other staff in his or her own nursery in the delivery of supervised toothbrushing.} is administered by National Health Service ("NHS") Scotland^{27Legend symbol denoting NHS Scotland consists of 14 regional NHS Boards which are responsible for the protection and improvement of their population's health and for the delivery of frontline healthcare services.} to ensure that nursery staff has the required skills to provide effective supervision. Added to this, NHS Scotland conducts twice-yearly reviews at each nursery to ensure that consistent standards of care are achieved in terms of toothbrushing practices and hygiene. Since 2014-2015, supervised toothbrushing has achieved near-universal adoption across Scotland.^{28Legend symbol denoting Since 2014-2015, over 95% of preschool establishments have participated in the toothbrushing programme. See University of Glasgow (2019).} It is also regarded as a cost-effective initiative with estimated savings in dental treatment exceeding 2.5 times the costs of implementation.^{29Legend symbol denoting See Anopa et al. (2015).}
• In terms of preventive dental care, the Childsmile programme provides topical fluoride treatment for preschool and younger children. The procedure – known as fluoride varnish application ("FVA") in Scotland – involves applying a fluoride-containing protective gel onto the tooth surface of children to halt or prevent tooth decay. FVA treatments are currently delivered to preschool children under the following arms of Childsmile:
  
  

  (a)

  Childsmile Practice is a government-funded and child-centred dental service delivered by community dental clinics30Legend symbol denoting Childsmile Practice is provided by public dental clinics, as well as private dental clinics contracted by NHS Scotland to deliver a specified range of dental services. across Scotland. Children can receive regular free dental check-ups at the clinics from 18 months of age, as well as twice-yearly FVAs upon reaching the age of two. With the dentist's approval, FVA treatments may also be delivered by dental nurses specifically trained for the task.31Legend symbol denoting Dental nurses as well as other support workers for Childsmile are required to attend training courses offered by NHS Scotland. Among others, the course covers core competencies in dental public health, use of fluoride, and working with children in the dental care setting. After successful completion of the course, dental nurses and/or support workers should receive mentoring from a dentist, therapist or hygienist in their own workplace before they can provide FVA treatment to children. For 2018-2019, around 41% of eligible preschool children had received at least one dose of FVA in community dental clinics;32Legend symbol denoting The cost of Childsmile Practice for children up to five years old amounted to £1.54 million (HK$15.4 million) in 2018-2019. See Public Health Scotland (2019). and

  (b)

  Childsmile Nursery is a school-based dental prevention service delivered to targeted nurseries. Priority is accorded to nurseries with the highest proportion of children who are living in relatively deprived areas, premised on the understanding that children from less privileged backgrounds often have higher risks of dental caries. Dental teams from Childsmile visit the targeted nurseries twice a year to provide extra FVA treatment within their premises. In 2018-2019, around 31% of eligible preschool children had received at least one dose of FVA in nurseries.33Legend symbol denoting Within a given year, a preschool child may receive FVA treatments from both Childsmile Practice and Childsmile Nursery. The rates of coverage for the two arms of service may thus overlap with each other.

• The supervised toothbrushing and FVA programmes of Childsmile have contributed to the steady decline in dental caries among preschool children in Scotland. Results of oral health surveys showed that the caries prevalence of six-year-old children in Scotland fell from 42% in 2008 to 26% in 2020, and their mean dmft score eased from 1.86 to 1.04 over the same period.^{34Legend symbol denoting See Public Health Scotland (2020).}

Singapore

• In Singapore, the Health Promotion Board^{35Legend symbol denoting Established in 2001, the Health Promotion Board is a government organization which administers a range of health promotion and disease prevention programmes including dental services for school children.} administers the School Dental Service ("SDS") which provides basic dental treatment for children aged three and four at child care centres^{36Legend symbol denoting In Singapore, child care centres provide full-day and half-day care programmes to children below seven years old.} participating in the Preschool Oral Health Screening and Fluoride Therapy Programme. The Programme comprises dental screening as well as the provision of fluoride treatment on those children assessed to be at risk of developing tooth decay. In 2019-2020, the Programme covered 53.2% of all child care centres and served more than 28 200 preschool children in Singapore.^{37Legend symbol denoting See Health Promotion Board (2021) and Early Childhood Development Agency (2021).} According to an epidemiological study by the National Dental Centre Singapore,^{38Legend symbol denoting National Dental Centre Singapore is an institution which provides full-service specialist dental care in Singapore. See National Dental Centre Singapore (2019).} the oral health programme was successful in reducing tooth decay amongst participating preschool children.^{39Legend symbol denoting According to National Dental Centre Singapore (2019), children who did not receive dental care were three times more likely to have severe early childhood caries when compared with those who were enrolled in the programme.}
• For primary and secondary students, SDS provides free dental screening, basic and preventive treatment in school dental clinics and mobile dental clinics with a view to promoting good oral health.^{40Legend symbol denoting Annually, Primary 1, 2, 4 and 6, as well as Secondary 1 and 3 students who are enrolled in the school dental programme are screened and treated by SDS. Students in other levels who require dental services may also visit the school dental clinics or mobile dental clinics for free consultation and treatment. See Health Promotion Board (2020).} The services are generally provided by dentists, dental therapists or advanced students in oral health therapy under close supervision. With near-universal enrolment, SDS has helped achieve better oral health among primary and secondary students as evidenced in their DMFT indices falling by 55% and 42% respectively between 2005 and 2020.^{41Legend symbol denoting The DMFT index for 12-year-old primary students fell from 0.77 in 2005 to 0.35 in 2020, whereas that for 15-year-old secondary students fell from 1.19 in 2005 to 0.69 in 2020. See Data.gov.sg (2021).}

Australia

• In Australia, the state and territory governments provide subsidized dental services^{42Legend symbol denoting The public dental services provided to children generally include preventive, restorative and emergency treatment. The majority of services are provided for free but a partial fee may be charged for some types of services and/or groups of children.} for the children of eligible age through the public healthcare system. Nevertheless, the eligibility criteria and scope of services often vary from place to place.^{43Legend symbol denoting For instance, while the public dental services in provinces such as New South Wales and South Australia cover children below 18 years old, other provinces such as Queensland and Victoria have stricter age eligibility requirements.} This, coupled with the long waiting time for public services, has prompted the federal government to introduce a means-tested dental care voucher scheme in 2008 as a dental safety net for needy children who cannot afford private dentists for dental treatment.
• The voucher scheme, currently known as the Child Dental Benefits Schedule ("CDBS")^{44Legend symbol denoting Prior to 2014, the voucher scheme was known as the Medicare Teen Dental Plan and only covered teenagers aged between 12 and 17.}, covers a wide age range of children (between 2 to 17 years old) from low-income families. A child is eligible if his or her family is qualified to receive specified types of social assistance from the Australian government.^{45Legend symbol denoting Eligibility for CDBS is linked to the receipt of relevant social payments from the Australian government, including but not limited to Family Tax Benefit Part A, Carer Payment, Parenting Payment, Special Benefit, or Youth Allowance. These social payments schemes have their own means tests and eligibility criteria.} Under CDBS, a child may claim up to A$1,013 (HK$5,430) in dental benefits over a two-year period,^{46Legend symbol denoting After two years, the child may access a new benefit cap provided that he or she remains eligible for CDBS.} covering basic dental services such as examination, teeth cleaning, fissure sealing^{47Legend symbol denoting Fissure sealing involves the addition of protective layers of plastic coating – known as fissure sealants – onto the grooves of the teeth to prevent tooth decay.}, filling and extraction. The dental vouchers may be used to access both public and private dental clinics. Services provided by the latter are remunerated by the government on a fee-for-service basis.
• According to the latest available data, CDBS had benefitted 1.07 million or 21.9% of children between 2 to 17 years old in 2017, incurring a total cost of A$334 million (HK$2 billion).^{48Legend symbol denoting See Commonwealth of Australia (2019).} Since its inception, the voucher scheme has helped divert some of the demand on public dental services and provided more timely access to dental care for needy children. For instance, in the state of New South Wales where some 98% of CDBS benefits were claimed via the private sector, there was a 50% drop in the number of children waiting for dental assessment and treatment in the public sector from December 2013 to June 2021.^{49Legend symbol denoting See New South Wales Government (2021).}

Concluding remarks

• Tooth decay is a chronic disease common amongst young children, but it can be prevented with reduced sugar intake, effective toothbrushing and preventive dental treatment. In Hong Kong, the oral health of primary students has improved over the years with the provision of dental care services. However, the present scope of services does not cover preschool children, which has resulted in persistently high rates of dental caries among five-year-old children in Hong Kong. Added to this, preschool children from less privileged backgrounds have a higher tendency to suffer from tooth decay.
• Some overseas places have implemented more robust oral health programmes with a wider scope of school- and/or community-based care services for young children with dental care needs. As seen from the dental care services in Scotland and Singapore, supervised toothbrushing and/or fluoride treatment for preschool children are relatively simple and cost-effective measures to alleviate the prevalence of early childhood caries. Meanwhile, Australia's dental voucher scheme has provided targeted financial support for needy children from low-income families to seek timely treatment for their oral health problems.

Prepared by Charlie LAM
Research Office
Information Services Division
Legislative Council Secretariat
27 October 2021