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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.
1,325 questions in 34 reviews · Oral medicine and oral cancer
current versionsNo studies 164 · 12.4%Ungraded 841 · 63.5%Very low 209 · 15.8%Low 72 · 5.4%Moderate 38 · 2.9%High 1 · 0.1%
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 |
|---|---|---|---|
More than 15 missing teeth vs 15 or fewer missing teeth Oral cancer risk · People with and without more than 15 missing teeth · Missing teeth >15 Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | OR 1.91 [1.01, 3.62] | 5 studies | Ungraded |
Intralesional dexamethasone injections vs Placebo injections Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -2.10 [-6.77, 2.57] | 1 study · 25 participants | Very low |
Intralesional dexamethasone injections vs Placebo injections Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -1.80 [-6.30, 2.70] | 1 study · 25 participants | Very low |
Missing teeth / tooth loss vs Fewer or no missing teeth Oral cancer (OC) · Adults in case-control studies of oral cancer · Not specified, Overall (all missing-teeth measures pooled) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | OR 1.20 [0.97, 1.48] | 6 studies | Ungraded |
Surgery plus Heister jaw opener vs Surgery plus wooden tongue depressors Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | Vadepally 2019 measured burning sensation on a VAS but did not fully report results, stating there was no significant difference between the 2 groups (p=0.617). | 1 study · 50 participants | Ungraded |
Oxitard (antioxidant) vs Aloe vera gel Difficulty in speech (participant-reported proxy) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | OR 0.32 [0.14, 0.76] | 1 study · 120 participants | Ungraded |
Intervention NR Oral cancer (OC) · Sensitivity analysis: excluding Moraes et al. [34] Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | OR 2.63 [1.92, 3.62] | 7 studies | Ungraded |
Abdominal dermal fat graft vs Nasolabial flap Adverse effects · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | Kania 2022 reported 3/30 serious adverse effects (graft failure) requiring prolonged hospital stay in the abdominal dermal fat graft group; no GRADE rating. | 1 study · 30 participants | Ungraded |
Pentoxifylline vs Placebo or no active treatment Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -0.15 [-5.04, 4.74] | 2 studies · 136 participants | Very low |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Participant satisfaction · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | The trials did not measure participant satisfaction. | 0 studies | No studies |
Intralesional betamethasone vs Placebo Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | Goel 2015 (3-arm: intralesional betamethasone vs lycopene vs placebo, 90 per arm): appeared to show increased interincisal distance in both intervention groups vs placebo, but only between-group differences with no… | 1 study · 180 participants | Ungraded |
Intralesional triamcinolone vs Intralesional triamcinolone plus salvianolic acid B Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -1.00 [-10.37, 8.37] | 1 study · 28 participants | Very low |
Intralesional steroid injections vs Alternative medicinal treatments Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -0.06 [-10.64, 10.52] | 2 studies · 58 participants | Very low |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Improvement in range of jaw movement · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | The trials did not measure range of jaw movement. | 0 studies | No studies |
Intralesional dexamethasone injections vs Placebo injections Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -52.00 [-62.04, -41.96] | 1 study · 25 participants | Very low |
Surgery plus Heister jaw opener vs Surgery plus wooden tongue depressors Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 0.92 [0.28, 1.56] | 1 study · 50 participants | Very low |
Abdominal dermal fat graft vs Nasolabial flap Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -3.60 [-5.17, -2.03] | 1 study · 30 participants | Very low |
Intralesional dexamethasone injections vs Placebo injections Adverse effects · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | Adverse effects (any): no adverse effects reported; 25 (1); no GRADE rating. | 1 study · 25 participants | Ungraded |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Quality of life · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | The trials did not measure quality of life. | 0 studies | No studies |
Tongue depressor stretches (physiotherapy) vs Intralesional steroid plus hyaluronidase injections Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 5.38 [-2.24, 13.00] | 1 study · 20 participants | Very low |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Difficulty in mouth opening (participant-reported proxy) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | OR 0.00 [0.00, 0.02] | 1 study · 100 participants | Ungraded |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Difficulty in swallowing (participant-reported proxy) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | OR 0.24 [0.10, 0.60] | 2 studies · 220 participants | Ungraded |
Intralesional steroid injections vs Alternative medicinal treatments Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 8.61 [-4.52, 21.74] | 3 studies · 98 participants | Very low |
Intralesional dexamethasone injections vs Placebo injections Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -46.00 [-53.44, -38.56] | 1 study · 25 participants | Very low |
Pentoxifylline vs Placebo or no active treatment Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 1.80 [1.02, 2.58] | 1 study · 106 participants | Low |
Intralesional triamcinolone vs Intralesional triamcinolone plus salvianolic acid B Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -16.30 [-28.15, -4.45] | 1 study · 28 participants | Very low |
Hydrocortisone plus hyaluronidase (intralesional) vs Triamcinolone plus hyaluronidase (intralesional) Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | Singh 2010 (hydrocortisone+hyaluronidase 50 vs triamcinolone+hyaluronidase 50): mouth opening reported categorically (trismus) rather than as continuous data, precluding quantitative analysis; authors found no… | 1 study · 100 participants | Ungraded |
Antioxidant capsules vs Topical aloe vera gel Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | Sudarshan 2012 (topical aloe vera 10 vs antioxidant capsules 10): reported improvement in interincisal distance but no baseline data, so change could not be determined; excluded from meta-analysis. | 1 study · 20 participants | Ungraded |
Pentoxifylline vs Multivitamin Severity of oral/mucosal burning pain/sensation · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | Rajendran 2006 concluded the intervention reduced pain, but pain intensity evaluations were inadequately defined and from interview data, making mean scores difficult to interpret. | 1 study · 29 participants | Ungraded |
Pentoxifylline vs Placebo or no active treatment Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -7.00 [-28.8, 42.8] | 1 study · 30 participants | Very low |
Vasodilators (isoxsuprine, xanthinol nicotinate) vs Placebo or no active treatment Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -38.79 [-52.06, -25.53] | 2 studies · 85 participants | Very low |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Direct costs · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) Interventions for managing oral submucous fibrosis (2024) · Cochrane | The trials did not measure costs. | 0 studies | No studies |
Oral cancer patients (cases) vs Healthy controls Clinical attachment loss (CAL) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, CAL (clinical attachment loss) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 1.94 [0.22, 3.66] | 2 studies | Ungraded |
Oxitard (antioxidant) vs Aloe vera gel Difficulty in swallowing (participant-reported proxy) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | OR 0.17 [0.07, 0.44] | 1 study · 120 participants | Ungraded |
Pentoxifylline vs Spirulina Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -8.00 [-14.47, -1.53] | 1 study · 40 participants | Low |
Hydrocortisone plus hyaluronidase (intralesional) vs Placebo or no active treatment Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -4.88 [-12.87, 3.11] | 1 study · 12 participants | Very low |
Intralesional triamcinolone vs Intralesional salvianolic acid B Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · More than 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -0.60 [-3.76, 2.56] | 1 study · 28 participants | Very low |
Levamisole vs Antioxidant (Antoxid) Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -9.10 [-16.23, -1.97] | 1 study · 30 participants | Very low |
Levamisole vs Antioxidant (Antoxid) Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -1.00 [-7.18, 5.18] | 1 study · 30 participants | Very low |
Clear aligners (CA) vs Conventional fixed orthodontic appliances (CF) Plaque accumulation (Plaque Index) · Orthodontic patients undergoing comprehensive treatment (late mixed or permanent dentition, no active caries) · Range 1 to 18 months (maximum time-point per study), Study design: randomized controlled trials White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | SMD -1.79 [-3.63, 0.04] | 3 studies · 111 participants | Moderate |
Surgery plus adjuvant radiotherapy vs Chemotherapy (chemoradiotherapy) Disease-free survival · Adults with oral cavity or oropharyngeal cancer · oral cavity Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Disease-free survival: not reported (Iyer 2015). | 0 studies | No studies |
Surgery plus radiotherapy vs Radiotherapy alone Locoregional recurrence · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Locoregional recurrence: not reported. | 0 studies | No studies |
Clear aligners (CA) vs Conventional fixed orthodontic appliances (CF) Plaque accumulation (Plaque Index) · Orthodontic patients undergoing comprehensive treatment (late mixed or permanent dentition, no active caries) · 6 months, Follow-up: 6 months White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | SMD -2.04 [-3.37, -0.70] | 5 studies · 253 participants | Ungraded |
Surgery vs Radiotherapy alone Adverse events associated with treatment · Adults with oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: grade 2+ treatment-related events similar (31/34 radiotherapy vs 33/34 surgery; RR 0.94, 0.83 to 1.06); more hearing loss/neutropenia/constipation/tinnitus with radiotherapy, more oral bleeding/trismus… | 1 study · 68 participants | Very low |
Surgery plus radiotherapy vs Radiotherapy alone Total mortality · Adults with oral cavity or oropharyngeal cancer · 3 years Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | HR 0.24 [0.10, 0.59] | 1 study · 35 participants | Very low |
Clear aligners (CA) vs Conventional fixed orthodontic appliances (CF) Incidence of white spot lesions (WSLs) · Orthodontic patients undergoing comprehensive treatment (late mixed or permanent dentition, no active caries) · End of orthodontic treatment (varying) White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | Not meta-analyzed (heterogeneous methods; tooth-based vs patient-based incidence). 4 studies assessed WSL incidence; 3 (Albhaisi 2020 [12]; Buschang 2019 [29]; Dallel 2020 [30]) reported a lower risk of developing WSLs… | 4 studies | Ungraded |
Elective radical (comprehensive) neck dissection vs Elective selective neck dissection Total mortality · Adults with oral cavity cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Total mortality: 2 trials reported HR but could not be pooled (different surgical procedures); neither indicated a difference (BHNCSG 1998 HR 1.14, 0.70 to 1.86; Bier 1994 HR 0.87, 0.41 to 1.83); 252 participants (2… | 2 studies · 252 participants | Very low |
Elective neck dissection (at time of primary tumour resection) vs Therapeutic (delayed) neck dissection Adverse events associated with treatment · Adults with oral cavity cancer (tongue or floor of mouth) and clinically negative neck nodes Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | RR 1.31 [1.11, 1.54] | 2 studies · 746 participants | Moderate |
Sentinel node biopsy (neck dissection only if biopsy positive) vs Elective neck dissection Recurrence · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Recurrence: Garrel 2020 reported that the number of patients with recurrences in both arms was almost identical; unable to use the data (variable follow-up); 279 participants (1 RCT). | 1 study · 279 participants | Very low |
Surgery plus radiotherapy vs Radiotherapy alone Disease-free survival · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Disease-free survival: not reported. | 0 studies | No studies |