Study selection and characteristics
The initial search yielded 1173 records, 616 duplicates were removed, and 557 records remained. Of these 520 were excluded as they were either descriptive or qualitative, included a population outside criterion age range, maternal interventions, prevalence studies or workforce related. The search of the grey literature yielded four articles for review of which none met the inclusion or exclusion criteria. Hand searching yielded one article. Thirty-seven eligible articles remained of which 9 met the inclusion or exclusion criteria for this review. Figure 1 demonstrates study selection.
Table 1 summarises the quality assessment, design, population, interventions, ecological approach and community engagement intensity and outcomes of each study.
Table 1
Description of studies included in systematic review (n = 9) by study, study design, participants, community engagement, ecological approach, intervention, outcomes and quality assessment rating
Study (n = 9) | Study design | Population Geographical area | Participants | EAS CEI score | Intervention strategies Targets31 Setting Timeframe | Outcomes | Quality Assessment EPHPP Global Score |
Gender | Age | Number | DMFT/DMFS | Caries | Knowledge and/ or behaviour | Other |
Arantes et al, 2010 43 | Repeat cross-sectional study (nested in prevalence study). | Xavante people of Brazil Oe village only - Etenheritipá | Both (results not reported by gender) | ≥ 2 years and 11–15 years | DMFT outcome (11–15 years): Time 1 (1999) = 212 (29) Time 2 (2004) = 281 (64) DMFS outcome (11–15 years): Time 1 (2004) = 281 (64) Time 2 (2007) = 372 (66) | 3 Moderate | 3 intervention strategies including: Education, prevention (Fluoride) using principles of participation of the community, promotion of general health, personnel training, utilisation of appropriate technology and fluoride Intervention 'targets': IND Community and clinical (clinical implied) 8 years | Outcome: DMFT/DMFS score Mean DMFS score for 11-15-year olds fell from 4.95 in 2004 to 2.39 in 2007 (p < 0.01) | ↓ in incidence of caries among 11–15 years from 80–53% between 1999 and 2007 (nt) | | | Weak |
Carberry 2004 40 | Pre-Post design | American Indian Navajo people Rural | Both (results not reported by gender) | 3–13 years | Time 1 = 180 Time 2 = 251 | 0 Moderate | Fluoride (0.2%) rinsing program (2 rinses per week) Intervention 'targets': IND and INT (family) Home and School Home: 3–4 years participated in the 'Headstart' program School: 5–13 years 1 year | ↓ DMFS score to 0.8 for 11 year old children (nt) | | | Compared with one year previous: ↑25% in dental appointments (nt) ↓% in dmft of 2nd year 'Headstart' children from 16.3–7.7% (nt) ↑'Evidence' of dental care by 1/3rd: to 67% in school children and to 47% in the 'HeadStart' children (nt) ↓% of 'active decay' from 63–37% (nt) Rate of sealant applications doubled ↑ in crowns on primary teeth 5 vs 49 ↑ in pulpotomy procedures 15 vs 42 | Weak |
Chen, et al, 2011 42 | Pre-Post design | Truku children in the Chongguang Tribe (Taiwan) Rural (Wenlan Village, Xiulin Township) | m = 34; f = 33 | 3–15 years | TOTAL: n = 67 7 − 15 years = 56 | 2 Light | 5 intervention strategies including giving lectures for children and parents, teaching videos for children, teaching children how to brush their teeth correctly, giving out tooth cleaning supplies, and handing out prepared dental care manuals to children Intervention 'targets': IND (including as member of peer group at school) and INT (family) Setting not described (implied either community OR school) 1 year | | | Outcome: Dental care knowledge √ ↑ in tooth-cleaning habits; knowledge of caries; knowledge of change of teeth; and periodical examination schedule (p < 0.001) √ ↑ in dietary habits | Outcome: Dental plaque levels (in subset of children n = 16) √ ↓in dental plaque | Weak |
Harrison et al, 2006 44 | Repeat cross-sectional | Canadian First Nations people Remote | Both (results not reported by gender) | All children on reserve (age not specified) | Time 1 = 34 Time 2 = 49 | 3 Moderate | 4 intervention strategies including daily school 'brush-ins'; weekly fluoride rinse for children ≥9 years and tri-annual fluoride varnish applications < 9 years; incentives; anticipatory guidance for parents; classroom health education Intervention 'targets': IND (including as member of peer group at school) and INT (family) School and clinic 3 years | | | | Outcome: 'Time units' needed to complete dental treatment for children Reduction in hours required to restore (p ≤ 0.001) or extract (p ≤ 0.01) teeth and to engage in preventative therapy (p ≤ 0.001) | Weak |
Johnson et al, 2014 39 | Repeat cross-sectional | Australian Aboriginal and/or Torres Strait Islander people Remote (5 small communities North Queensland) | Both (53% male) | 6–15 years | TOTAL: n = 324 10-12 years: Time 1 = 131 Time 2 = 67 (dmft and caries in primary dentition only) 10–15 years: Time 1 = 224 Time 2 = 127 (DMFT and caries in permanent dentition only) | 0 Light | Introduction of a reticulated fluoridated water supply Intervention 'target': Community Environmental 7 years | Outcome: dmft and DMFT √ ↓ mean dmft (missing & filled only) at 10 years (p < 0.05) √ ↓ mean: DMFT at 15 years Decayed at 15 years Missing at 14 years Filled at 10–15 years (p < 0.05) | Outcome: caries (primary and permanent dentition) ↓ in overall caries prevalence and severity from 2005 to 2012 by 37.3%. | | Fewer teeth had restorations in both surveys | Moderate |
McNab et al 2008 41 | Pre-Post design | Canadian First Nations people Remote | Both (results not reported by gender) | 5–16 years | Time 1 = 26 Time 2 = 40 13 participated in pre and post intervention evaluation Numbers within age range not stated | 2 Moderate | 4 intervention strategies including daily brush-ins, fluoride application, educational presentations, and incentive scheme Intervention 'target': IND including as member of peer group at school through the education strategy School 3 years | Outcome: dmfs/DMFS and dmft/DMFT √ ↓ dmfs/DMFS (p < 0.005) √ ↓ dmft/DMFT (p < 0.05) | | | Prior to intervention 8% children cavity free Post intervention 32% cavity free | Weak |
Olubunmi & Olushola, 2002 37 | Randomised Controlled Trial | Nigeria Urban | TOTAL: m = 59; f = 61 Grp1: m = 22; f = 18 Grp 2: m = 19; f = 21 Grp 3: m = 18; f = 22 | 11–12 years | TOTAL: n = 120 Intervention = 80 (2 groups of 40) | 2 Light | Health Education strategy comparing three groups (two intervention and one control) Intervention 1: 20 minute oral health education video of a story acted by well-known local actors Intervention 2: 20 minute verbal oral health education Intervention 'target': IND (peer group at school). School 6 weeks | | | | Outcome: Oral hygiene, debris and calculus scores Post intervention all scores lower √ differences in mean debris scores between intervention and control groups with lowest score for verbal education (p < 0.001) √ differences in mean calculus scores between intervention and control groups (p < 0.001) √ differences in oral hygiene scores between intervention and control groups (p < 0.001) Video education showed greater odds of improvement in oral hygiene than verbal education video | Strong |
Wilder et al 2014 36 | Pre-Post (cohort) study (nested within a Mixed methods design) | Australian Aboriginal and Torres Strait Islander people Rural. | m = 7; f = 10 | 5–12 years (mean age 7.5 years) | TOTAL: n = 17 Numbers within age range not stated. | 4 Moderate | Pilot study of 'New model' of care including 5 intervention strategies delivered monthly to children and families in the child’s home. Intervention strategies included: partnerships (including community consultations; employment of Aboriginal and/or Torres Strait Islander health workers); 'cultural aides and equipment' (timers, charts, toothbrushes), education package; oral health assessment and dental treatment Intervention 'targets': IND and INT (families). Home, school and community 10 months | Outcome: dmfs ↓ dmfs from 3.7 to 3.5 (nt) | | | Outcomes: Dental and periodontal indicators √ ↓ in proportion of unmet restorative needs compared to baseline 71% vs 34.4% (p < 0.05) √ ↑in average numbers of fissure sealants present in permanent teeth from 0.4 to 1.6 (p < 0.01) Gingival Index change: 58.8% no change; 23.5% level 1 improvement; 5.9% level 2 improvement, and less level 1 and 2 dis-improvement Plaque Index change: 47.1% no change; 29.4% level 1 improvement; 5.9% level 2 improvement; 17.6% level 1 of dis-improvement | Strong |
Yang et al, 2009 38 | Cluster randomised controlled trial | Taiwan (Pingtung County) Rural | TOTAL: m = 68; f = 67. Intervention: m = 33; f = 34. | 7th Grade | TOTAL: n = 135 Intervention = 607 | 0 Light | Intervention group received a specially designed education program covering a range of oral health-related topics delivered using 8 modules (40 minutes each held once per week) Intervention 'target': IND (as member of peer group at school) School setting 8 weeks | | | Outcome: Knowledge and Behaviour √ ↑ oral health knowledge (p < 0.001) √ ↑ increase in tooth-brushing frequency (p < 0.001) √ ↓ in tobacco use (p = 001) | Most (87%) students considered the educational program excellent or good | Moderate |
CEI = Community Engagement Intensity EAS = Ecological Approach Score (4 = intervention reported as including at least 2 strategy types and ≥ 3 settings, with lesser scores reflect fewer strategy types and settings, and 0 = 1 strategy regardless of number of settings IND = individual; INT = Interpersonal environment dmft = Number of decayed, missing or filled teeth (primary dentition) dmfs = Number of decayed, missing or filled teeth surfaces (primary dentition) dmft/DMFT = Number of decayed, missing or filled teeth (primary/permanent dentition) DMFT = Number of decayed, missing or filled teeth (permanent dentition) DMFS = Number of decayed, missing or filled surfaces (permanent dentition) ↑ = increase; ↓ = decrease √ = statistically significant nt = no test for difference applied |
Quality Assessment
Two of the nine studies in this review were given an EPHPP global rating of strong (36, 37); two as moderate (38, 39), and the remaining five as weak (40–44). Additional file 1 describes the quality assessment components of each study. All but one (41) of the included studies were rated either moderate or strong for selection bias, indicating that the participants were likely to be representative of the target population (45). The majority of studies were rated moderate (36, 39–42) or strong (37, 38) for study design.
Study Design
Study designs included three repeat cross-sectional studies (39, 43, 44) with one of these nested in a prevalence study (43); four pre-post studies (36, 40–42) with one nested in a mixed methods study (36); one randomized controlled trial (RCT) (37), and one cluster RCT (38) (Table 1). Due to the relatively small number, and heterogeneity, of the studies, no meta-analysis was performed.
Study population
Studies were conducted in diverse countries and geographical areas. Two studies were conducted in Australian rural or remote communities (36, 39); two studies in Taiwanese rural communities (38, 42) ; two in remote Canadian First Nations communities (41, 44); one in an American Indian (rural) setting (40), one in rural Brazil (43); and one in urban African (Nigerian) (37) communities (Table 1).
The sample size of studies varied between 17–324 participants. Where gender was reported there was an even proportion of male and female participants. Five studies reported on outcomes for adolescents (37–40, 43); with two of these studies designed specifically for this age group (37, 38) (Table 1).
Interventions
Eight out of the nine studies described intervention strategies targeting the individual (36–38, 40–44); four of these included the family (36, 40, 42, 44) as the enablers of change in the oral health status of their child (Table 1). This is important in this context as family and peer group (such as in the school setting) are considered part of the child’s interpersonal environment, and can be enablers for strategies targeting the individual (35). The remaining study reported on an environmental intervention (39) which was the provision of a water reticulation system including fluoride. Schools were the most common setting for study interventions. Three interventions were delivered interventions only in schools (37, 38, 41); three included schools as one of a number of intervention settings (36, 40, 44); and one implying that a school was the setting (42).
Five intervention strategies emerged from the review. These included: 1) Educational (n = 7) (36–38, 41–44) which targeted behaviour and knowledge of children and/or parents; 2) Clinical (n = 4) (36, 40, 41, 43) which included fluoride varnish or rinse and dental treatment; 3) Provision of incentives (n = 2), one using cash (44) and the other using ‘prizes’ (41); 4) Employment of local Health Workers (n = 2) (36, 43); and 5) Environmental change (n = 1) (39). Five studies delivered more than one intervention strategy (36, 41–44).
Ecological approach and Community Engagement Intensity
Only one study (36) was given an EAS score of four; indicating it included at least two strategy types and was implemented in more than three settings. Furthermore, no study reported a strong level of CEI. These were concerning results given that the features of these measures are recommended for conduct of research in Indigenous communities. When CEI features were examined six studies reported community governance or engagement in the research however little information on the nature of this was provided. Five studies reported that ‘capacity building’ occurred however when this feature was further examined capacity building was largely the formation of partnerships (36, 40, 41, 43, 44), with no studies describing career development pathways for Indigenous staff, and only one reporting on the participation of the community in decision making (40). None reported providing feedback of results to participating communities who participated. The number of studies which reported on each key feature of CEI are presented in Fig. 2. Additionally, details of key feature of CEI can be found in Additional File 2. It should be noted that not all studies may have reported details of community engagement despite this being a key component of study design with Indigenous communities.
Outcomes
Eight of the nine studies reported statistically significant improvements in at least one component of oral health (Table
1). The most frequently reported outcome (n = 5) was change in dmft/DMFT or the number of decayed, missing or filled tooth surfaces (dmfs/DMFS) (36, 39–41, 43); with two of these studies finding significant improvements of between p < 0.001 and p < 005 (39, 41). Two studies reported significant changes in oral health knowledge and/or behaviour (38, 42). Two studies reported a decline in caries prevalence; however, this was not tested for statistical significance (39,43). Six studies reported more than one outcome (36, 37, 39–43). A number of other statistically significant outcomes were reported across three studies including: reduction in treatment hours required (p
≤ 0.001) (44); reduced levels of debris, calculus and oral hygiene scores following video education compared to verbal education (p < 0.05) (37); decreased levels of unmet restorative needs and increased numbers of fissure sealants (p
≤ 0.01) (36).