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Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.
42 questions in 10 reviews · intervention: Oral hygiene/education · outcome domain: Periodontal/gingival
current versionsNo studies 2 · 4.8%Ungraded 4 · 9.5%Very low 19 · 45.2%Low 15 · 35.7%Moderate 2 · 4.8%High 0 · 0%
Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.
Intervention categories, outcome domains and clusters are a proposed key pending human validation. Clear all filters
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Theory-based oral health education/promotion interventions (HBM, TPB, SCT, HAPA, TTM, PMT, SOC, PRECEDE-PROCEED, MI) vs Control (waitlist, routine/standard oral health education, or minimal intervention) Periodontal health (gingival/periodontal indices) · Children and adolescents aged 5-18 years · Post-intervention (follow-up 2 weeks to 6 months, varies by study), Overall Health promotion theory-based educational interventions for improving oral health in children and… (2025) | SMD -1.18 [-1.83, -0.53] | 4 studies · 3342 participants | Moderate |
Primary school-based interventions (one or more of: school health policy, oral health education, healthy school environment, access to oral health services, community involvement) vs No intervention or usual practice/activities Oral hygiene measured by mean gingival scores · Primary school children (aged 3-16 years) attending primary school in low- and middle-income countries (LMICs) · Post-intervention; follow-up varied across studies (interventions ranged from <2 years to >=2 years and longer) Effectiveness of primary school-based interventions in improving oral health of children in low- and… (2022) | SMD 0.12 [-0.32, 0.55] | 3 studies · 1573 participants | Very low |
Rubber/elastomeric cleaning stick plus toothbrushing vs Toothbrushing alone Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.07 [-0.15, 0.01] | 1 study · 30 participants | Very low |
Rubber/elastomeric cleaning stick plus toothbrushing vs Flossing plus toothbrushing Gingivitis (gingival index) · Adults, 16 years and older (dentate) · 4 to 6 weeks Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | SMD -0.22 [-0.69, 0.24] | 6 studies · 256 participants | Very low |
Wooden cleaning stick plus toothbrushing vs Toothbrushing alone Gingivitis (gingival index) · Adults, 16 years and older (dentate) Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | Gingivitis measured by gingival index: Not measured. | 0 studies | No studies |
Interdental brushing plus toothbrushing vs Toothbrushing alone Gingivitis (gingival index) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.53 [-0.83, -0.23] | 1 study · 62 participants | Very low |
Oral irrigation plus toothbrushing vs Flossing plus toothbrushing Gingivitis (gingival index) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.06 [-0.12, 0.00] | 1 study · 63 participants | Very low |
Wooden cleaning stick plus toothbrushing vs Toothbrushing alone Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 3 months Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.25 [-0.37, -0.13] | 1 study · 24 participants | Very low |
Electric toothbrush (self, carer or carer-assisted brushing) vs Manual toothbrush (self, carer or carer-assisted brushing) Gingival inflammation (short term) · Children and adults with mixed levels of ID; setting home, residential, day care, school, mixed or not specified · Short term (<6 weeks) Oral hygiene interventions for people with intellectual disabilities (2019) · Cochrane | Electric vs manual toothbrush. Assorted gingival indices scale 0-4, 2-4 weeks; 252 participants (4 RCTs); Low. Four studies showed no significant differences for gingival inflammation short term; data could not be… | 4 studies · 252 participants | Low |
Oral irrigation plus toothbrushing vs Toothbrushing alone Gingivitis (gingival index) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | SMD -0.48 [-0.89, -0.06] | 4 studies · 380 participants | Very low |
Interdental brushing plus toothbrushing vs Flossing plus toothbrushing Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 4 to 6 weeks Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.06 [-0.08, -0.03] | 6 studies · 234 participants | Low |
Flossing plus toothbrushing vs Toothbrushing alone Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.03 [-0.14, 0.08] | 2 studies · 158 participants | Very low |
Scheduled dental recall intervals (1-, 3- or 6-monthly; oral hygiene instruction with or without scale and polish) plus daily supervised toothbrushing by carers vs Usual care (no specific treatment) Gingival pocketing (long term) · Adults (mean age 30.9 years), level of ID unclear; setting day centre · Long term (>12 months) Oral hygiene interventions for people with intellectual disabilities (2019) · Cochrane | MD -0.60 [-0.97, -0.23] | 1 study · 304 participants | Low |
Interdental brushing plus toothbrushing vs Flossing plus toothbrushing Gingivitis (gingival index) · Adults, 16 years and older (dentate) · 4 to 6 weeks Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | SMD -0.40 [-0.70, -0.11] | 3 studies · 183 participants | Low |
Rubber/elastomeric cleaning stick plus toothbrushing vs Interdental brushing plus toothbrushing Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.02 [-0.10, 0.06] | 1 study · 31 participants | Very low |
Flossing plus toothbrushing vs Toothbrushing alone Gingivitis (gingival index) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | SMD -0.58 [-1.12, -0.04] | 8 studies · 585 participants | Low |
Oral irrigation plus toothbrushing vs Toothbrushing alone Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.00 [-0.07, 0.06] | 2 studies · 126 participants | Low |
Oral irrigation plus toothbrushing vs Flossing plus toothbrushing Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.12 [-0.19, -0.05] | 2 studies · 133 participants | Low |
Rubber/elastomeric cleaning stick plus toothbrushing vs Interdental brushing plus toothbrushing Gingivitis (gingival index) · Adults, 16 years and older (dentate) · 4 to 6 weeks Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD 0.10 [-0.32, 0.52] | 1 study · 61 participants | Very low |
Electric toothbrush (self, carer or carer-assisted brushing) vs Manual toothbrush (self, carer or carer-assisted brushing) Gingival inflammation (medium term) · Children and adults with mixed levels of ID; setting home, residential, day care, school, mixed or not specified · Medium term (6 weeks to 12 months) Oral hygiene interventions for people with intellectual disabilities (2019) · Cochrane | MD 0.02 [-0.06, 0.09] | 2 studies · 120 participants | Moderate |
Scheduled dental recall intervals (1-, 3- or 6-monthly; oral hygiene instruction with or without scale and polish) plus daily supervised toothbrushing by carers vs Usual care (no specific treatment) Gingival bleeding (long term) · Adults (mean age 30.9 years), level of ID unclear; setting day centre · Long term (>12 months) Oral hygiene interventions for people with intellectual disabilities (2019) · Cochrane | MD -0.20 [-0.86, 0.46] | 1 study · 304 participants | Low |
Wooden cleaning stick plus toothbrushing vs Flossing plus toothbrushing Gingivitis (gingival index) · Adults, 16 years and older (dentate) Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | Gingivitis measured by gingival index: Not measured. | 0 studies | No studies |
Interdental brushing plus toothbrushing vs Toothbrushing alone Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.05 [-0.13, 0.03] | 1 study · 31 participants | Very low |
Special manual toothbrush (self, carer or carer-assisted brushing) vs Conventional manual toothbrush (self, carer or carer-assisted brushing) Gingival inflammation (short term) · Children and adults with mixed levels of ID; setting home, residential, day care, school, mixed or not specified · Short term (<6 weeks) Oral hygiene interventions for people with intellectual disabilities (2019) · Cochrane | MD -0.10 [-0.77, 0.57] | 1 study · 25 participants | Low |
Oral hygiene training (toothbrushing routine) of people with ID vs No oral hygiene training of people with ID Gingival inflammation (short term) · Children and adults with mild to profound ID; setting residential or school · Short term (<6 weeks) Oral hygiene interventions for people with intellectual disabilities (2019) · Cochrane | MD -0.28 [-0.90, 0.34] | 1 study · 10 participants | Very low |
Rubber/elastomeric cleaning stick plus toothbrushing vs Toothbrushing alone Gingivitis (gingival index) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.01 [-0.19, 0.21] | 1 study · 12 participants | Very low |
Oral hygiene care training of carers vs No training (or a placebo training session) of carers Gingival inflammation (medium term) · People with mixed levels of ID (age range unclear); setting residential · Medium term (6 weeks to 12 months) Oral hygiene interventions for people with intellectual disabilities (2019) · Cochrane | MD -0.09 [-0.63, 0.45] | 2 studies · 99 participants | Low |
Daily toothbrushing by a dental student vs Twice-weekly or once-weekly toothbrushing by a dental student Gingival inflammation (short term) · People aged 15 to 30 years with mixed levels of ID; setting residential · Short term (<6 weeks) Oral hygiene interventions for people with intellectual disabilities (2019) · Cochrane | Daily vs twice-weekly or once-weekly toothbrushing by dental students. Buccal and labial Loe & Silness index, mean 21 days; 80 participants (1 RCT); Low. Brushing daily most likely reduced gingival inflammation more… | 1 study · 80 participants | Low |
Special manual toothbrush (self, carer or carer-assisted brushing) vs Conventional manual toothbrush (self, carer or carer-assisted brushing) Gingival inflammation (medium term) · Children and adults with mixed levels of ID; setting home, residential, day care, school, mixed or not specified · Medium term (6 weeks to 12 months) Oral hygiene interventions for people with intellectual disabilities (2019) · Cochrane | MD -12.40 [-24.31, -0.49] | 1 study · 18 participants | Very low |
Wooden cleaning stick plus toothbrushing vs Flossing plus toothbrushing Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 3 months Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD 0.01 [-0.12, 0.14] | 1 study · 24 participants | Very low |
Rubber/elastomeric cleaning stick plus toothbrushing vs Flossing plus toothbrushing Gingivitis (proportion of bleeding sites) · Adults, 16 years and older (dentate) · 1 month Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling… (2019) · Cochrane | MD -0.03 [-0.08, 0.03] | 5 studies · 212 participants | Low |
Any form of one-to-one oral hygiene advice (OHA) vs No OHA Periodontal health: gingivitis · Children or adults (fit and healthy, or with a well-defined medical condition) · 3 to 36 months One‐to‐one oral hygiene advice provided in a dental setting for oral health (2018) · Cochrane | SoF: 1 small study in adults had contradictory results at 3 and 6 months; the other study in adults showed evidence of a benefit for OHA at all time points (12, 24, 36 months). Results: Hetland 1982 MD 0.25 (0.05 to… | 2 studies · 235 participants | Very low |
Any form of one-to-one oral hygiene advice (OHA) vs No OHA Periodontal health: plaque levels · Children or adults (fit and healthy, or with a well-defined medical condition) · 6 to 36 months One‐to‐one oral hygiene advice provided in a dental setting for oral health (2018) · Cochrane | SoF: Both studies at all time points consistently showed a benefit in plaque reduction for OHA. Results: Hetland 1982 MD -0.41 (-0.54 to -0.28) at 3mo, -0.44 (-0.56 to -0.32) at 6mo; Hugoson 2007 MD -13.00 (-19.89 to… | 2 studies · 235 participants | Low |
Educational intervention with information and practical components (theoretical oral health education plus practical skills training) for nursing staff and/or residents vs (Optimised) usual care Gingivitis · Nursing home residents (mean age 78.3 to 86.0 years; more than 66% women; 62.1% to 87.3% with dental prostheses) · 3 to 6 months Oral health educational interventions for nursing home staff and residents (2016) · Cochrane | SoF: Gingivitis (Gingival Bleeding Index and method of Suomi; follow-up 3 to 6 months). No meta-analysis (data not comparable). 245 participants (3 RCTs); low quality. Comment: 3 studies at unclear risk of bias showed… | 3 studies · 245 participants | Low |
Low socioeconomic position and adverse behavioural factors vs Higher socioeconomic position and fewer adverse behaviours Systemic inflammation (C-reactive protein) and periodontal disease progression · General-population adults (German cohort) · 5-year follow-up Social-Biological Interactions in Oral Disease: A 'Cells to Society' View. (2016) | no estimate extracted | 1 study · 3300 participants | Ungraded |
Interdental brushing plus toothbrushing vs Flossing plus toothbrushing Gingivitis (bleeding and gingival indices; standardised across indices) · Dentate adults aged 16 years and older · 1 month (4 to 6 weeks) Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults (2013) · Cochrane | SMD -0.53 [-0.81, -0.24] | 7 studies · 326 participants | Low |
Interdental brushing plus toothbrushing vs Flossing plus toothbrushing Gingivitis (bleeding and gingival indices; standardised across indices) · Dentate adults aged 16 years and older · 3 months (12 weeks) Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults (2013) · Cochrane | SMD -1.98 [-5.42, 1.47] | 2 studies · 107 participants | Very low |
Interdental brushing plus toothbrushing vs Toothbrushing alone Gingivitis (Loe-Silness gingival index, interproximal; scale 0 to 4) · Dentate adults aged 16 years and older · 4 weeks (1 month) Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults (2013) · Cochrane | MD -0.53 [-0.83, -0.23] | 1 study · 62 participants | Very low |
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse) Gingivitis (Gingival Index, 0-3 scale; SMD) · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease) · 3 months Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane | SMD -0.41 [-0.68, -0.14] | 6 studies · 656 participants | Ungraded |
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse) Gingivitis (Loe-Silness/bleeding indices; SMD) · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease) · 1 month Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane | SMD -0.36 [-0.66, -0.05] | 7 studies · 489 participants | Very low |
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse) Gingivitis (Gingival Index, 0-3 scale; SMD) · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease) · 6 months Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane | SMD -0.72 [-1.09, -0.35] | 4 studies · 564 participants | Ungraded |
Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs No (active) intervention (usual/standard dental care or no-treatment control) Gingival bleeding · Adults (aged 18 or over) diagnosed with periodontal disease (gingivitis or periodontitis) · 4 months Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal… (2007) · Cochrane | Little 1997 reported decreased gingival bleeding in the active intervention group: gingival bleeding present in 9% of the intervention group at baseline and 4% at 4-month follow up, versus 10% of the control group on… | 1 study · 107 participants | Ungraded |