Hase 1998.

Study characteristics
Methods	Trial design: parallel (3 arms ‐ 2 arms relevant to this review) Location: military regiment, Halmstad, Sweden Number of centres: 1 Study duration: recruitment period is not stated but the duration of rinsing was 6 months
Participants	Participants: military conscripts and military staff (adult males) with gingivitis Inclusion criteria: males aged at least 18 years; at least 25% bleeding sites of all gingival sites (6 sites per tooth) on BOP using a Florida‐probe with a pressure of 0.25 N to the bottom of the pocket; minimum 16 healthy teeth without crowns, bridge‐work, or ill‐fitting dental restorations Exclusion criteria: 4 or more teeth with cavities or pocket probing depth 5 mm or more; previous hypersensitive reactions to drugs; alcohol or drug addiction; severe liver or renal disease; psychiatric disorders; severe disability with multiple drug therapy; receiving antibiotics within 6 weeks of the prestudy visit; antiphlogistics (including sprays with corticosteroids) or anticholinergic drugs such as antiparkinson drugs or antidepressants Baseline gingivitis: (% sites BOP) Gp A: mean 42.7 (SE 2.7); Gp B: mean 47.3 (SE 2.6); Gp C: mean 43.9 (SE 2.7) (unpublished data) Age at baseline (years): Gp A: mean 24 (SD 10); Gp B: mean 26 (SD 7); Gp C: mean 23 (SD 7) Gender: males only Number randomised: 140 (Table 2 page 748) (Gp A: 47; Gp B: 48; Gp C: 45) Number evaluated (per protocol analysis): 100 (Gp A: 30; Gp B: 37; Gp C: 33)
Interventions	Comparison: CHX digluconate rinse versus delmopinol hydrochloride rinse* versus placebo rinse Gp A (n = 47): CHX (0.2% Hibitane Dental), 10 mL, 1 min, twice daily *Gp B (n = 48): delmopinol hydrochloride (0.2%), same routine. We excluded this arm from our risk of bias and analysis Gp C (n = 45): same routine using placebo (same as Gp B but without delmopinol and sodium hydroxide) Prophylaxis at baseline: supra‐ and subgingival scaling OHI: participants were instructed not to change their normal mechanical tooth cleaning methods during the study Partly supervised rinsing (mostly supervised but occasionally unsupervised due to military training) Timing of rinsing in relation to toothbrushing: after toothbrushing Postrinsing instructions: not reported
Outcomes	Gingivitis (gingival BOP using a Florida‐probe with a pressure of 0.25 N to the bottom of the pocket (Gibbs 1988, Löe 1967)), measured at 3 and 6 months Plaque (PI, TQH, Turesky 1970) measured at 3 and 6 months Calculus (Volpe‐Manhold Calculus Index, Volpe 1967), measured at 3 and 6 months Extrinsic tooth staining (Staining Index of Shaw & Murray 1977), measured at 3 and 6 months Adverse events (transient anaesthetic sensation, taste modification, staining (teeth or tongue or both)) were recorded Microbiological monitoring of plaque and salivary microflora was performed during the treatment period and also 3 months after the end of treatment for 65 patients ‐ results (excluding BOP which is presented here) presented separately ‐ not relevant to this review
Funding	Not reported
Notes	Sample size calculation: based on BOP. The standard deviation was estimated to 14 and a difference of 10% units between placebo and delmopinol was considered worth detecting. Based on a power of 95% at significance level of 5%, 50 participants per group were required. Therefore this was not achieved Adverse effects: transient anaesthetic sensation in the oral mucosa especially at the tip of the tongue in delmopinol and CHX groups reached the same level of reporting at 6 months. Taste modification was commonly reported in both the delmopinol and CHX groups. Staining of teeth or tongue was common in the CHX group Adverse effects at 6 months (Table 4) (% participants experiencing the adverse effect): local anaesthesia/hypoasthesia/parasthesia CHX 18%, placebo 0%, delmopinol 22%; taste loss/taste perversion: CHX 16%, placebo 0%, delmopinol 24%; discolouration teeth/discolouration tongue: CHX 13%, placebo 7%, delmopinol 8% Declarations/conflicts of interest: nothing explicitly stated but first author was employee of Biosurface AB, Malmo, Sweden
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Patients were allocated to treatment groups according to a computer‐generated randomisation list, where treatment was balanced within blocks of 6 patients" Comment: adequate method of random sequence generation
Allocation concealment (selection bias)	Unclear risk	Quote: "Packaging and labelling were carried out at an independent Clinical Service Department" Comment: it is not clear whether the assignment of subjects to groups was carried out at the independent Clinical Service Department
Blinding of participants and personnel (performance bias) All outcomes	High risk	The study is reported to be "double‐blind" and "The various test solutions were dispensed in identical 200 ml amber glass bottles." The placebo was the same composition as the delmopinol rinse but without the delmopinol and sodium hydroxide. It is unclear who supervised the rinsing and if they were blinded to allocation of the rinse Comment: the higher level of staining of the teeth and tongue in the CHX group (plus greater taste modification and transient anaesthetic sensation in the active groups) meant that participants could have worked out which group they were in and this could have affected their oral health behaviours and hence the outcomes. The direction of this potential bias is not clear
Blinding of outcome assessment (detection bias) All outcomes	High risk	The study is reported to be "double‐blind". Assessments were made by 5 trained dental hygienists who followed the same subjects throughout the treatment period Comment: the authors do not report precisely who was blinded, but even if this includes the outcomes assessors the higher level of staining of the teeth and tongue in the CHX group meant that they could not be adequately blinded and this could have affected the outcome assessment. The direction of this potential bias is not clear
Incomplete outcome data (attrition bias) All outcomes	High risk	At 6 months 29 participants are excluded from the analysis in the study arms of interest to this review but only 16 are reported as withdrawn from the study with reasons for withdrawal. Data presented here for loss to follow‐up are based on the total lost to follow‐up (n = 29) Attrition at 6 months 29/92 (31.5%). By group: CHX 17/47 (36.2%), placebo 12/45 (26.7%). Reasons for loss to follow‐up: CHX: adverse events/lack of cooperation, release from military service; placebo: adverse events/lack of cooperation, release from military service, moved away Comment: very high attrition which may be related to type of mouthrinse and could feasibly introduce bias in the results
Selective reporting (reporting bias)	Low risk	Information on means and SEs are presented graphically. From correspondence with the author, additional information was obtained on means and SEs which enabled calculation of SDs from SEs and inclusion of these data in the meta‐analyses
Other bias	Unclear risk	Assessments were made by 5 trained dental hygienists who followed the same subjects throughout the treatment period. A calibration session for all assessments was performed before the start of treatment but the results of the calibration (Inter‐ and intraexaminer reliability) are not reported Mean age was balanced across groups at baseline. No statistically significant demographic differences between the groups were recorded. Baseline BOP and mean plaque scores appear balanced but the statistical significance of the differences is not reported