Gap finder
Search review questions
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 |
|---|---|---|---|
Amifostine vs No treatment/placebo Hypotension (adverse effect) · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | RR 9.20 [2.84, 29.83] | 3 studies · 376 participants | Low |
Zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate, zinc acetate, or polaprezinc) vs Placebo Taste acuity improvement - objective outcome (dichotomous data) · Patients with taste disturbances (dysgeusia/hypogeusia; idiopathic, zinc-deficient, or secondary to chronic renal… · Mean 3 months, Idiopathic/zinc-deficient taste disorder Interventions for managing taste disturbances (2017) · Cochrane | RR 1.42 [1.09, 1.84] | 2 studies · 292 participants | Very low |
Biperiden plus pilocarpine vs No treatment Dysphagia (WHO grade 3+) · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region · 12 months postRT Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | RR 0.25 [0.03, 2.11] | 1 study · 60 participants | Ungraded |
Granulocyte-macrophage colony-stimulating factor (GM-CSF) vs Placebo or no treatment Oral mucositis (severe) · Adults with cancer receiving treatment · RT to head and neck Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 0.31 [0.01, 7.09] | 1 study · 29 participants | Very low |
Acupuncture vs Sham control (deactivated laser sham acupuncture) Adverse events · Patients with idiopathic dysgeusia and hypogeusia Interventions for managing taste disturbances (2017) · Cochrane | Results: The acupuncture trial (Brandt 2008) did not give any data on adverse events in either group. | 0 studies | No studies |
Keratinocyte growth factor (KGF; palifermin or repifermin), intravenous vs Placebo Oral mucositis (any severity) · Adults with cancer receiving treatment · Chemotherapy alone for mixed cancers Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 0.71 [0.60, 0.85] | 2 studies · 215 participants | Ungraded |
Amifostine vs No treatment/placebo Quality of life (Patient Benefit Questionnaire, 10-point scale) · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region · 12 months postRT Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | MD 0.70 [0.20, 1.20] | 1 study · 180 participants | Very low |
Biperiden plus pilocarpine vs No treatment Salivary flow rate (unstimulated) · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region · End of RT Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | Insufficient evidence, from a single trial of 60 participants, to determine the effect on unstimulated salivary flow rate at the end of RT (Rode 1999; Analysis 2.1) | 1 study · 60 participants | Ungraded |
Epidermal growth factor (EGF), oral spray vs Placebo Normalcy of diet (total parenteral nutrition) · Adults with cancer receiving treatment · Chemoradiotherapy to the head and neck Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 1.03 [0.55, 1.94] | 1 study · 136 participants | Ungraded |
Intestinal trefoil factor (ITF), oral spray vs Placebo Oral mucositis (severe) · Adults receiving chemotherapy alone for colorectal cancer Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 1.52 [0.06, 36.39] | 1 study · 99 participants | Ungraded |
Acupuncture vs Sham control (deactivated laser sham acupuncture) Taste acuity improvement · Patients with idiopathic dysgeusia and hypogeusia Interventions for managing taste disturbances (2017) · Cochrane | Results: There were no data on taste acuity improvement in the included acupuncture trial (Brandt 2008). | 0 studies | No studies |
Bethanechol vs Artificial saliva Quality of life · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | No data on either quality of life or other oral related symptoms were reported. | 0 studies | No studies |
Keratinocyte growth factor (KGF; palifermin or repifermin), intravenous vs Placebo Oral mucositis (severe) · Adults with cancer receiving treatment · RT to head and neck with cisplatin/fluorouracil Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 0.79 [0.69, 0.90] | 3 studies · 471 participants | High |
Selenium vs No intervention Salivary flow rate · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | No data on salivary flow rates were reported. | 0 studies | No studies |
Biperiden plus pilocarpine vs No treatment Xerostomia · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | No xerostomia data related to the effectiveness of biperiden and pilocarpine were reported (Rode 1999). | 0 studies | No studies |
Antimicrobial lozenge vs Placebo Salivary flow rate · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | No data on salivary flow rates were reported. | 0 studies | No studies |
Amifostine (intravenous) vs Amifostine (subcutaneous) Xerostomia (grade >= 2, 0-4 scale) · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region · Up to and including 3 months postRT Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | RR 1.03 [0.76, 1.40] | 1 study · 263 participants | Ungraded |
Dietary supplements (alpha lipoic acid +/- vitamins/lycopene/green tea; hypericum; Catuama; lycopene) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF5 Dietary supplements vs placebo. Symptom relief short-term: insufficient or contradictory evidence regarding benefit of any evaluated dietary supplement; 628 participants (12 RCTs); very low. Subgroups: ALA without… | 12 studies · 628 participants | Very low |
Topical treatments (benzydamine hydrochloride oral rinse) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), benzydamine hydrochloride Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF9 Topical treatments vs placebo. Symptom relief short-term: insufficient or contradictory evidence regarding benefit of any evaluated topical treatment; 150 participants (4 RCTs); very low. Subgroups: benzydamine (1… | 4 studies · 150 participants | Very low |
NSAIDs (ketorolac oral rinse; systemic celecoxib) vs Placebo or no treatment Clinical resolution (oral lesion not completely resolved) · People with a diagnosis of oral leukoplakia · 3 months Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | SoF 3, Clinical resolution (not completely resolved) at 3 months: '1 study evaluated systemic treatment and 1 evaluated topical treatment. Neither found benefit for NSAIDs.' No GRADE. Effects text: celecoxib… | 2 studies | Ungraded |
Vitamin A or retinoids (systemic or topical; incl. 13-cis-retinoic acid, acitretin) vs Placebo or no treatment Oral cancer development · People with a diagnosis of oral leukoplakia · 24 months (treatment lasted 12 months) Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | RR 0.11 [0.01, 2.05] | 1 study · 85 participants | Very low |
Topical bleomycin vs Placebo or no treatment Oral cancer development · People with a diagnosis of oral leukoplakia · up to 7 years Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | RR 3.00 [0.32, 27.83] | 1 study · 20 participants | Very low |
Benzodiazepines (topical clonazepam) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), topical clonazepam Interventions for treating burning mouth syndrome (2016) · Cochrane | MD -1.89 [-2.19, -1.59] | 2 studies · 111 participants | Very low |
Anticonvulsants (gabapentin 300 mg/day, +/- alpha lipoic acid) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 4.00 [2.09, 7.67] | 1 study · 100 participants | Very low |
Antidepressants (trazodone 200 mg/day) vs Placebo Adverse effects: dizziness · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 11.61 [1.66, 81.04] | 1 study · 37 participants | Very low |
Topical bleomycin vs Placebo or no treatment Clinical resolution (oral lesion not completely resolved) · People with a diagnosis of oral leukoplakia · 3 months Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | RR 0.55 [0.29, 1.04] | 1 study · 22 participants | Very low |
Psychological therapies (cognitive therapy) vs Placebo Change in feeling of dryness · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF8: No included study reported change in feeling of dryness. | 0 studies | No studies |
Benzodiazepines (topical clonazepam) vs Placebo Change in feeling of dryness · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF3: No included studies reported change in feeling of dryness. | 0 studies | No studies |
Electromagnetic radiation (low-level laser therapy) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | MD -30.36 [-44.22, -16.50] | 1 study · 58 participants | Very low |
Physical barriers (tongue protector) vs Placebo Change in taste · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF7: No included studies reported change in taste. | 0 studies | No studies |
NSAIDs (ketorolac oral rinse; systemic celecoxib) vs Placebo or no treatment Safety of the intervention (adverse effects) · People with a diagnosis of oral leukoplakia · over 3 months Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | SoF 3, Safety of the intervention over 3 months: systemic celecoxib (1 study) - 32 intervention participants reported 56 adverse effects, 20 placebo participants reported 20; 4 grade 3 events; 2 discontinued. Ketorolac… | 2 studies | Ungraded |
NSAIDs (ketorolac oral rinse; systemic celecoxib) vs Placebo or no treatment Improvement of histological features (not improved) · People with a diagnosis of oral leukoplakia Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | SoF 3, Histological changes: 'Not measured'. Effects text: 'Histological changes were not among the outcomes in the studies testing NSAIDs.' | 0 studies | No studies |
Antidepressants (trazodone 200 mg/day) vs Placebo Adverse effects: tremor · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 2.11 [0.21, 21.32] | 1 study · 37 participants | Very low |
Benzodiazepines (systemic clonazepam 0.5 mg/day) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), systemic clonazepam Interventions for treating burning mouth syndrome (2016) · Cochrane | MD 0.00 [-1.86, 1.86] | 1 study · 20 participants | Very low |
Topical bleomycin vs Placebo or no treatment Safety of the intervention (adverse effects) · People with a diagnosis of oral leukoplakia · up to 3 months Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | SoF 5, Safety of the intervention up to 3 months: 'All patients in the bleomycin group developed erythema with erosion by the end of the applications, whereas erythema developed in the placebo group. Discomfort was… | 1 study | Ungraded |
Psychological therapies (cognitive therapy) vs Placebo Change in quality of life (QoL) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF8: No included study reported change in QoL. | 0 studies | No studies |
Topical treatments (benzydamine hydrochloride oral rinse) vs Placebo Adverse effects · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), benzydamine hydrochloride Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF9. Adverse effects: single study narratively reported that no adverse effects occurred from benzydamine hydrochloride oral rinse; 20 participants (1 RCT); very low. | 1 study · 20 participants | Very low |
Dietary supplements (Catuama herbal compound) vs Placebo Adverse effects: exacerbation of symptoms · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), Catuama Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 1.12 [0.33, 3.83] | 1 study · 72 participants | Very low |
Vitamin A or retinoids (systemic or topical; incl. 13-cis-retinoic acid, acitretin) vs Placebo or no treatment Clinical resolution (oral lesion not completely resolved) · People with a diagnosis of oral leukoplakia · 4 to 12 months Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | SoF 1, Clinical resolution (not completely resolved) at 4 to 12 months: 'Studies could not be combined in meta-analysis. One study evaluated topical treatment and did not find evidence of benefit; 3 studies of systemic… | 4 studies | Ungraded |
Dietary supplements (Catuama herbal compound) vs Placebo Adverse effects: drowsiness · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), Catuama Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 2.69 [0.11, 63.96] | 1 study · 72 participants | Very low |
Benzodiazepines (topical clonazepam) vs Placebo Adverse effects: drowsiness · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), topical clonazepam Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 2.71 [0.84, 8.74] | 2 studies · 114 participants | Very low |
Herbal extracts (tea components; Chinese herbal mixture; freeze-dried black raspberry gel) vs Placebo or no treatment Clinical resolution (oral lesion not completely resolved) · People with a diagnosis of oral leukoplakia · 3 to 6 months Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | SoF 4, Clinical resolution (not completely resolved) at 3 to 6 months: '3 studies (freeze-dried black raspberry gel, green tea extract capsules, mixed tea) did not find evidence of benefit.' No GRADE. Effects text:… | 4 studies | Ungraded |
Benzodiazepines (topical clonazepam) vs Placebo Adverse effects: dry mouth · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), topical clonazepam Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 3.00 [0.13, 70.16] | 1 study · 48 participants | Very low |
Systemic beta carotene or carotenoids (incl. lycopene) vs Placebo or no treatment Improvement of histological features (not improved) · People with a diagnosis of oral leukoplakia · 5 months (treatment lasted 3 months) Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | RR 0.24 [0.12, 0.46] | 1 study · 58 participants | Low |
Bowman-Birk inhibitor vs Placebo or no treatment Improvement of histological features (not improved) · People with a diagnosis of oral leukoplakia Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | SoF 6, Histological changes: 'Not measured'. Effects text: data on histological changes from Armstrong 2013 were not available for analysis, but study authors reported no statistically significant differences in… | 1 study | Ungraded |
Cholinergics (bethanechol 15 mg/day) vs Placebo Adverse effects (narrative) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF4. Adverse effects: single study narratively reported 4 participants (20%) in the bethanechol arm experienced adverse events (nausea, dizziness, blood pressure fall, cold perspiration or sporadic abdominal pain);… | 1 study · 40 participants | Very low |
Anticonvulsants (gabapentin + alpha lipoic acid) vs Placebo Adverse effects: drowsiness · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 14.52 [0.73, 290.44] | 1 study · 80 participants | Very low |
Physical barriers (tongue protector) vs Placebo Change in QoL - anxiety (surrogate marker) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | MD 0.16 [-3.19, 3.51] | 1 study · 50 participants | Very low |
Cholinergics (bethanechol 15 mg/day) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 5.00 [0.26, 98.00] | 1 study · 40 participants | Very low |
Psychological therapies (cognitive therapy) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · long-term (>3 to 6 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | MD -3.20 [-4.22, -2.18] | 1 study · 30 participants | Very low |