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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.
793 questions in 32 reviews · Periodontology
current versionsNo studies 148 · 18.7%Ungraded 429 · 54.1%Very low 137 · 17.3%Low 53 · 6.7%Moderate 14 · 1.8%High 12 · 1.5%
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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Gingival Index (GI) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | MD 0.15 [0.11, 0.19] | 4 studies · 488 participants | Low |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Clinical Attachment Level (CAL) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | The loss of clinical attachment level (CAL) is greater in patients with cleft lip and palate than in healthy controls (p < 0.00001) | NR | Ungraded |
Intervention NR Bleeding on Probing (BoP) · Cleft lip/palate vs healthy controls Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | no estimate extracted | 1 study | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Bleeding Index (BI) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | the bleeding index (BI) showed significantly higher values for subjects with cleft lip and/or palate (BI p < 0.0001) | NR | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Oral microbiota composition · Individuals assessed for oral microbiota (mainly children and adolescents) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | no estimate extracted | 8 studies | Ungraded |
Unilateral cleft lip and palate (UCLP) vs Bilateral cleft lip and palate (BCLP) Plaque Index (PI) · Patients with cleft lip and palate (CLP) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | MD -0.13 [-0.38, 0.12] | 2 studies · 117 participants | Ungraded |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Probing Pocket Depth (PPD) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | MD 0.88 [0.82, 0.95] | 3 studies · 340 participants | Low |
Orofacial cleft (cleft lip and/or palate) as exposure vs Healthy controls without cleft Plaque Index (PI) · Individuals assessed for periodontal health (mainly children and adolescents, age >2 years) Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of… (2025) | MD 0.29 [0.24, 0.34] | 6 studies · 1618 participants | Low |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Pocket closure · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Three studies evaluated the proportion of closed pockets three months after treatment (Al-Zahrani 2011; Courval 2020; Rodrigues 2023); studies used different criteria to measure this outcome. All studies reported an… | 3 studies | Ungraded |
Dental caries (DT not equal to 0) vs No dental caries Periodontitis (prevalence) · Adults · Adjusted OR Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.57 [1.32, 1.86] | 3 studies | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Non-standard periodontitis definition Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.38 [1.07, 1.79] | 2 studies | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Patient satisfaction · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | No studies reported data for this outcome. | NR | No studies |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Number of ibuprofen tablets required · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 7 days Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD 1.58 [-4.55, 7.71] | 1 study · 41 participants | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Any adverse effect related to aPDT · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Risk with control: 23 studies reported that no adverse effects of aPDT were observed. Number of participants (studies): 639 (24 studies). Certainty: Moderate. (24 studies reported adverse effects, with all studies… | 24 studies · 639 participants | Moderate |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Quality of life · Adults (> 18 years) with peri-implant mucositis, receiving active treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Only one study reported evidence for adjunctive aPDT in people with peri-implant disease (Al Rifaiy 2022). Data were only available for two outcomes (PPD and BOP), both reported only at three months. No studies… | NR | No studies |
Non-syndromic cleft lip and palate (CLP) status and its oral microbiota (exposure/grouping) vs Children and adolescents aged 0-18 years without CLP (controls) Dental caries (proportion of patients with caries) · Children and adolescents aged 0-18 years with non-syndromic cleft lip and palate (CLP) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | OR 2.03 [1.46, 2.84] | 3 studies · 688 participants | Ungraded |
Intervention NR Periodontopathogenic microbiota composition · Narrative: Campylobacter/Fusobacterium/F. nucleatum/Prevotella intermedia-nigrescens/Parvimonas micra/Porphyromonas gingivalis in CLP Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | no estimate extracted | 6 studies | Ungraded |
Non-syndromic cleft lip and palate (CLP) status and its oral microbiota (exposure/grouping) vs Children and adolescents aged 0-18 years without CLP (controls) Lactobacillus spp. salivary/plaque counts (cariogenic microbiota) · Children and adolescents aged 0-18 years with non-syndromic cleft lip and palate (CLP) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | For the outcome of the presence of Lactobacillus spp., there were no significant differences between patients with CLP and healthy patients, and the diversity of the studies led to high heterogeneity; however, the p… | NR | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Change in probing pocket depth (PPD) · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 0.44 [0.29, 0.59] | 35 studies · 873 participants | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Adjusted OR Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.28 [0.85, 1.93] | 2 studies | Ungraded |
Single preoperative dose of systemic antibiotics (clindamycin 600 mg), total chemo-mechanical debridement and root filling vs Matched placebo, total chemo-mechanical debridement and root filling Swelling at 24 hours · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 24 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | No data available for this outcome. | 0 studies | No studies |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Percussion pain at 24 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 24 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD -0.32 [-0.85, 0.21] | 1 study · 41 participants | Ungraded |
Oral cancer patients (cases) vs Healthy controls Periodontal parameters (all measures pooled) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, Overall (all periodontal measures pooled) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 0.95 [0.41, 1.49] | 5 studies | Ungraded |
Non-syndromic cleft lip and palate (CLP) status and its oral microbiota (exposure/grouping) vs Children and adolescents aged 0-18 years without CLP (controls) Streptococcus mutans salivary/plaque counts (cariogenic microbiota) · Children and adolescents aged 0-18 years with non-syndromic cleft lip and palate (CLP) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | Two studies were analyzed that reported the outcome in means of the presence of Streptococcus mutans, and that there was no difference between the means for healthy patients and those with CLP. The results of these… | 2 studies | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Change in clinical attachment level (CAL) · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 0.36 [0.24, 0.48] | 34 studies · 875 participants | Ungraded |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Pain at 24 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 24 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD -0.03 [-0.53, 0.47] | 2 studies · 61 participants | Very low |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Swelling at 48 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 48 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | SMD 0.04 [-0.47, 0.55] | 2 studies · 61 participants | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Change in gingival recession (REC) · Adults (> 18 years) with peri-implant mucositis, receiving active treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Only one study reported evidence for adjunctive aPDT in people with peri-implant disease (Al Rifaiy 2022). Data were only available for two outcomes (PPD and BOP), both reported only at three months. No studies… | NR | No studies |
Oral cancer patients (cases) vs Healthy controls Periodontal pocket depth (PPD) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, PPD (periodontal pocket depth) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 1.64 [-0.20, 3.47] | 2 studies | Ungraded |
Salivary Actinobacillus level vs Not specified Salivary S. mutans level · Patients with aggressive periodontitis · Overall Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 0.08 [0.01, 0.85] | 1 study | Ungraded |
Dental caries (DT not equal to 0) vs No dental caries Periodontitis (prevalence) · Adults · Crude OR Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 2.35 [2.04, 2.70] | 2 studies | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Change in clinical attachment level (CAL) · Adults (> 18 years) with recurrent periodontitis, receiving supportive (maintenance) periodontal care · 6 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 0.07 [-0.26, 0.40] | 2 studies · 85 participants | Very low |
Periodontitis / periodontal disease (history or clinical diagnosis) vs No periodontitis (individuals without periodontal disease) Oral cancer (OC) · Adults in case-control studies of oral cancer; people assessed for periodontitis · Not specified, Overall (random-effects pooled estimate) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | OR 2.94 [2.13, 4.07] | 8 studies · 6927 participants | Low |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Mean DMFT (decayed, missing, filled teeth) · Adults · Overall Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | WMD 0.87 [-0.03, 1.76] | 4 studies | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Standard periodontitis definition Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.62 [1.20, 2.18] | 8 studies | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Age 30-64 years Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.67 [1.37, 2.03] | 3 studies | Ungraded |
Single preoperative dose of systemic antibiotics (clindamycin 600 mg), total chemo-mechanical debridement and root filling vs Matched placebo, total chemo-mechanical debridement and root filling Pain at 24 hours · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 24 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | The median pain at 24 hours in the control group was 3 (range 0 to 10); the median pain at 24 hours in the intervention group was the same (median 3, range 0 to 8). P = 0.219 (Mann-Whitney U). | 1 study · 72 participants | Low |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Swelling at 24 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 24 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | SMD 0.27 [-0.23, 0.78] | 2 studies · 62 participants | Very low |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Pain at 48 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 48 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD 0.32 [-0.22, 0.86] | 2 studies · 61 participants | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Change in probing pocket depth (PPD) · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 6 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 0.52 [0.31, 0.74] | 15 studies · 452 participants | Very low |
Oral cancer patients (cases) vs Healthy controls Alveolar bone loss (ABL) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, ABL (alveolar bone loss) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 0.18 [-2.34, 2.69] | 2 studies | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Root caries · Adults · Root caries Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 2.10 [1.03, 4.29] | 4 studies | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Outcome NR · Adults (> 18 years) with peri-implant mucositis, receiving supportive treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Planned comparison; no studies met the inclusion criteria. The review found only one study of peri-implant disease (peri-implant mucositis, active treatment) and no studies including people with peri-implantitis… | NR | No studies |
Single preoperative dose of systemic antibiotics (clindamycin 600 mg), total chemo-mechanical debridement and root filling vs Matched placebo, total chemo-mechanical debridement and root filling Swelling at 7 days · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 7 days Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | RR 0.50 [0.10, 2.56] | 1 study · 72 participants | Low |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Change in bleeding on probing (BOP) · Adults (> 18 years) with recurrent periodontitis, receiving supportive (maintenance) periodontal care · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 2.38 [-1.34, 6.10] | 5 studies · 231 participants | Ungraded |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Pain at 72 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 72 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD 0.08 [-0.38, 0.54] | 2 studies · 61 participants | Very low |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Change in bleeding on probing (BOP) · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 6 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 5.72 [1.62, 9.81] | 5 studies · 171 participants | Very low |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Outcome NR · Adults (> 18 years) with peri-implantitis, receiving active treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Planned comparison; no studies met the inclusion criteria. The review found only one study of peri-implant disease (peri-implant mucositis, active treatment) and no studies including people with peri-implantitis… | NR | No studies |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Change in bleeding on probing (BOP) · Adults (> 18 years) with recurrent periodontitis, receiving supportive (maintenance) periodontal care · 6 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 4.98 [-2.51, 12.46] | 3 studies · 127 participants | Very low |
Single preoperative dose of systemic antibiotics (clindamycin 600 mg), total chemo-mechanical debridement and root filling vs Matched placebo, total chemo-mechanical debridement and root filling Pain at 48 hours · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 48 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | Median pain at 48 hours 1 (range 0 to 9) in the antibiotic group versus 2 (range 0 to 10) in the control group. P = 0.242 (Mann-Whitney U). | 1 study · 72 participants | Ungraded |