Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Neutron radiotherapy showed no clear difference in total mortality compared with conventional photon radiotherapy; GRADE not reported.
1 finding from 1 review
HR 1.10 [0.90, 1.34]
3 studies
GRADE not reported
Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Accelerated/split-course radiotherapy showed no clear difference in total mortality compared with conventional (standard) fractionation radiotherapy; GRADE not reported.
1 finding from 1 review
Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
1 finding from 1 review
Quality of life · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
1 finding from 1 review
Bjarnason 2009: no statistically significant difference in quality of life scores (data not reported). Morning radiotherapy was associated with significantly less weight loss after 5 months.
1 study · 216 participants
GRADE not reported
Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Morning radiotherapy showed no clear difference in locoregional control compared with afternoon radiotherapy; GRADE not reported.
1 finding from 1 review
Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Lower total dose radiotherapy (67.2 Gy over 5.6 weeks) showed no clear difference in total mortality compared with conventional/standard total dose radiotherapy (72 Gy); GRADE not reported.
1 finding from 1 review
HR 1.38 [0.83, 2.29]
1 study
GRADE not reported
Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Pre-operative radiotherapy (plus surgery) showed no clear difference in total mortality compared with surgery alone; GRADE not reported.
1 finding from 1 review
HR 0.83 [0.64, 1.07]
1 study
GRADE not reported
Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
1 finding from 1 review
Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Higher total dose radiotherapy (76.8 Gy over 6.4 weeks) showed no clear difference in locoregional control compared with conventional/standard total dose radiotherapy (72 Gy); GRADE not reported.
1 finding from 1 review
HR 0.78 [0.55, 1.11]
1 study
GRADE not reported
Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Hyperfractionated/accelerated/split-course radiotherapy showed no clear difference in locoregional control compared with conventional (standard) fractionation radiotherapy; GRADE not reported.
1 finding from 1 review
Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Hyperfractionated/accelerated radiotherapy showed no clear difference in total mortality compared with conventional (standard) fractionation radiotherapy; GRADE not reported.
1 finding from 1 review
Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Pre-operative and post-operative radiotherapy showed no clear difference in total mortality compared with post-operative radiotherapy alone; GRADE not reported.
1 finding from 1 review
HR 0.67 [0.35, 1.28]
1 study
GRADE not reported
Altered fractionation radiotherapy plus chemotherapy vs Chemoradiotherapy with standard (conventional) fractionation
Outcome not reported · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
The review found no eligible studies for this question.
1 finding from 1 review
Disease-free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
1 finding from 1 review
Accelerated vs conventional, disease free survival: both trials reported this, but substantial clinical and statistical heterogeneity (P = 0.0004, I2 = 92%) meant a pooled analysis was not reported (Analysis 1.3).
2 studies
GRADE not reported
Disease-free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
1 finding from 1 review
Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
Pre-operative radiotherapy (plus surgery) showed no clear difference in locoregional control compared with surgery alone; GRADE not reported.
1 finding from 1 review
RR 0.63 [0.28, 1.46]
1 study
GRADE not reported
Altered fractionation radiotherapy vs Chemoradiotherapy (concurrent, standard fractionation)
Outcome not reported · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and neck cancer trials…
The review found no eligible studies for this question.
1 finding from 1 review
Interleukin-8 (IL-8) · Humans who use e-cigarettes (mostly adults, often with periodontal disease) assessed for oral proinflammatory markers
Meta-analysis suggests no significant effect of e-cigarette use on the salivary level of Interleukin-8 (IL-8) (6 studies), though heterogeneity was high (I2=84%) and the pooled estimate appears only in Figure 3C (unavailable); GCF data were limited (1 study(ies)) (ungraded).
1 finding from 1 review
Interleukin-6 (IL-6) · Humans who use e-cigarettes (mostly adults, often with periodontal disease) assessed for oral proinflammatory markers
Meta-analysis suggests no significant effect of e-cigarette use on the salivary level of Interleukin-6 (IL-6) (6 studies), though heterogeneity was high (I2=95%) and the pooled estimate appears only in Figure 3D (unavailable); GCF data were limited (1 study(ies)) (ungraded).
1 finding from 1 review
Downregulation of S. mutans virulence/biofilm gene expression (gtfB, gtfC, ftf) · Cariogenic bacteria (mainly Streptococcus mutans reference strains) and oral biofilms in vitro
Postbiotics reduce expression of S. mutans biofilm/virulence genes (gtfB, gtfC, ftf) in vitro (ungraded narrative synthesis).
1 finding from 1 review
Postbiotics and Dental Caries: A Systematic Review. 2025 All outcomesExposure 24 h to 7 days · Laboratory (in vitro)
Postbiotics downregulated expression of S. mutans virulence and exopolysaccharide-synthesis genes (e.g., gtfB, gtfC, gtfD, ftf) in 10 in vitro studies; no pooled estimate.
8 studies
GRADE not reported