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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.
866 questions in 43 reviews · Oral and maxillofacial surgery
current versionsNo studies 188 · 21.7%Ungraded 548 · 63.3%Very low 81 · 9.4%Low 37 · 4.3%Moderate 8 · 0.9%High 4 · 0.5%
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 |
|---|---|---|---|
Second molar at Nolla developmental stage 6-7 at extraction vs Second molar at later Nolla stages at extraction Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 55.1 [3.0, at least 100.0] | 1 study | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Recurrence rate · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 3 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Discomfort · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 1 as 'Not reported'; this outcome was not reported by any included study for this comparison. Discomfort was not reported in any included study across the whole review. | 0 studies | No studies |
Occlusal splint vs Another occlusal splint with a different mechanism of action Self-reported joint pain when chewing · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 2 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Extraction of the permanent first molar vs None (single-group prevalence) Spontaneous space closure · Children and adolescents (<18 years) after extraction of a permanent first molar before eruption of the permanent… · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | Prevalence 48.1 [34.5, 62.0] | 11 studies · 1095 participants | Ungraded |
Higher mean patient age (per 1 year) vs Lower mean patient age (per 1-year decrement) Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 0.59 [0.20, >100.00] | 3 studies | Ungraded |
Occlusal splint vs Pharmacological therapy Frequency of joint noise · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Depression · People with temporomandibular disorders (TMD) · Short term, Disc displacement with reduction (DDwR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -0.25 [-0.52, 0.02] | 1 study · 60 participants | Ungraded |
Occlusal splint vs Acupuncture Muscle pain when chewing · People with temporomandibular disorders (TMD) · Short term (1 month), Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 0.10 [-0.80, 1.00] | 1 study · 40 participants | Very low |
Second molar distally inclined at extraction vs Second molar upright at extraction Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 1.18 [0.43, 3.21] | 3 studies | Ungraded |
Occlusal splint vs Another occlusal splint with a different mechanism of action Frequency of joint noise · People with temporomandibular disorders (TMD) · Short term (3 months), Disc displacement with reduction (DDwR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 0.80 [0.07, 9.18] | 1 study · 9 participants | Very low |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Severity of joint noise · People with temporomandibular disorders (TMD) · Long term (4 months), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 5.92 [0.18, 11.66] | 1 study · 20 participants | Very low |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Joint pain at rest · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -2.59 [-4.21, -0.97] | 1 study · 39 participants | Very low |
Unilateral extraction of the mandibular first permanent molar vs Bilateral extraction of the mandibular first permanent molars Midline deviation of the mandibular arch · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 11.6 [1.9, 70.3] | 1 study | Ungraded |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Muscle pain when chewing · People with temporomandibular disorders (TMD) · Short term (3 months), Disc displacement without reduction (DDwoR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -1.97 [-2.37, -1.57] | 1 study · 84 participants | Very low |
Occlusal splint vs Acupuncture Discomfort · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 5 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Second molar at Demirjian stage F-G at extraction vs Second molar at Demirjian stage D-E at extraction Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 0.68 [0.28, 1.66] | 4 studies | Ungraded |
Occlusal splint vs Pharmacological therapy Muscle pain at mastication · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Occlusal splint vs Another occlusal splint with a different mechanism of action Joint pain at rest · People with temporomandibular disorders (TMD) · Long term (12 months), Disc displacement with reduction (DDwR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 7.00 [0.41, 120.16] | 1 study · 20 participants | Very low |
Second molar at Demirjian stage A-D at extraction vs Second molar at Demirjian stage G-H at extraction Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 2.75 [0.50, 15.10] | 3 studies | Ungraded |
Occlusal splint vs Pharmacological therapy Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term, Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -2.95 [-6.87, 0.97] | 1 study · 40 participants | Ungraded |
Occlusal splint vs Acupuncture Self-reported joint pain when chewing · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 5 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Extraction of the mandibular permanent first molar vs None (single-group prevalence) Rotation of the mandibular second premolar · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | Prevalence 60.0 [10.7, 95.0] | 2 studies · 105 participants | Ungraded |
Male sex vs Female sex Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 1.38 [0.37, 5.14] | 2 studies | Ungraded |
Occlusal splint vs Pharmacological therapy Muscle pain at rest · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Severity of joint noise · People with temporomandibular disorders (TMD) · Long term (4 months), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -0.58 [-7.09, 5.93] | 1 study · 20 participants | Very low |
Second molar at Demirjian stage E at extraction vs Second molar at Demirjian stage F-H at extraction Spontaneous space closure · Children and adolescents after extraction of a maxillary permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Maxilla Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 4.78 [1.56, 14.66] | 3 studies · 252 participants | Low |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Depression · People with temporomandibular disorders (TMD) · Short term, Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -2.58 [-4.62, -0.54] | 1 study · 32 participants | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Participant satisfaction or quality of life · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -7.56 [-14.50, -0.63] | 2 studies · 75 participants | Ungraded |
Occlusal splint vs Acupuncture Participant satisfaction or quality of life · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 0.80 [-7.36, 8.96] | 1 study · 30 participants | Ungraded |
Intervention NR Spontaneous space closure · Maxilla: M2 Demirjian A-D vs G-H Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR >100.00 | 1 study | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Muscle pain when chewing · People with temporomandibular disorders (TMD) · Short term (mean 3 months), Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 0.17 [0.02, 1.26] | 1 study · 40 participants | Very low |
Cleft lip and palate vs No cleft lip and palate Lactobacillus spp. mean levels/counts · Children and adolescents aged 0 to 18 years with nonsyndromic cleft lip and palate Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | MD 1.40 [1.33, 1.47] | 2 studies · 152 participants | Ungraded |
M2 Demirjian stages F-G vs M2 Demirjian stages E-D Spontaneous space closure · Children and adolescents with maxillary permanent first molar extraction · Follow-up to complete eruption of the permanent second molar, Maxilla Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR >100.00 [0.01, >100.00] | 3 studies | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Joint pain at rest · People with temporomandibular disorders (TMD) · Short term (6 weeks), Disc displacement without reduction (DDwoR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 0.85 [0.47, 1.57] | 1 study · 31 participants | Very low |
Second molar at Demirjian stage E-F at extraction vs Second molar at Demirjian stage G-H at extraction Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 4.44 [0.43, 46.10] | 3 studies | Ungraded |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Frequency of joint noise · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 4 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Second molar at Demirjian stage A-D at extraction vs Second molar at Demirjian stage F-H at extraction Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 3.11 [1.25, 7.72] | 3 studies · 95 participants | Low |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Recurrence rate · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 4 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Second molar mesially inclined at extraction vs Second molar upright at extraction Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 0.68 [0.27, 1.71] | 3 studies | Ungraded |
Intervention NR Cariogenic microbiota counts (Streptococcus mutans, Lactobacillus spp.) · Narrative synthesis: significantly higher in CLP vs controls (Ahluwalia, Lucas, Hassani, Cheng, Sundell) Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and… (2024) | no estimate extracted | 5 studies | Ungraded |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Frequency of joint noise · People with temporomandibular disorders (TMD) · Short term (mean 10 weeks), Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 1.18 [0.63, 2.20] | 1 study · 60 participants | Very low |
Occlusal splint vs Another occlusal splint with a different mechanism of action Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term (12 weeks), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 0.63 [-3.16, 4.42] | 1 study · 40 participants | Ungraded |
Occlusal splint vs Acupuncture Muscle pain at rest · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 5 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term, Disc displacement (with/without reduction) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -2.41 [-7.78, 2.96] | 1 study · 30 participants | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Frequency of joint noise · People with temporomandibular disorders (TMD) · Short term (3 months), Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 1.50 [0.32, 6.94] | 1 study · 18 participants | Very low |
Extraction at patient age <8 years vs Extraction at patient age >10 years Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 5.01 [1.45, 17.30] | 2 studies · 15 participants | Low |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term (6 weeks), Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 1.40 [-7.19, 9.99] | 1 study · 20 participants | Ungraded |
Extraction at patient age 8-10 years vs Extraction at patient age >10 years Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 3.32 [1.73, 6.36] | 3 studies · 109 participants | Low |
Occlusal splint vs Pharmacological therapy Joint pain at rest · People with temporomandibular disorders (TMD) · Short term, Osteoarthritis / mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 1.87 [0.57, 6.07] | 1 study · 29 participants | Very low |