What do systematic reviews say?

4% SHMP chewing gum vs placebo

It is very uncertain whether 4% SHMP chewing gum changes tooth whitening - assessed by the dentist compared with placebo (very low certainty).

• Home‐based chemically‐induced whitening (bleaching) of teeth in adults 2018 · Cochrane All outcomes

  12 weeks
  MD -0.14 [-0.38, 0.10]
  1 study · 108 participants
  Very low

1% STPP chewing gum vs placebo

It is very uncertain whether 1% STPP chewing gum changes tooth whitening - assessed by the dentist compared with placebo (very low certainty).

• Home‐based chemically‐induced whitening (bleaching) of teeth in adults 2018 · Cochrane All outcomes

  6 weeks
  MD 0.18 [0.10, 0.26]
  1 study · 108 participants
  Very low

Xylitol chewing gum vs No treatment or non-cariogenic control

The review found no eligible studies for this question.

• Xylitol‐containing products for preventing dental caries in children and adults 2015 · Cochrane All outcomes

  At least 1 year
  It was surprising that there were no eligible randomised trials testing xylitol chewing gums against either no treatment or a non-cariogenic control.
  0 studies
  No studies found

5.6% SHMP chewing gum vs placebo

It is very uncertain whether 5.6% SHMP chewing gum changes tooth whitening - assessed by the dentist compared with placebo (very low certainty).

• Home‐based chemically‐induced whitening (bleaching) of teeth in adults 2018 · Cochrane All outcomes

  3 days
  MD 2.60 [1.45, 3.75]
  1 study · 20 participants
  Very low

7.5% SHMP chewing gum vs placebo

It is very uncertain whether 7.5% SHMP chewing gum changes tooth whitening - assessed by the dentist compared with placebo (very low certainty).

• Home‐based chemically‐induced whitening (bleaching) of teeth in adults 2018 · Cochrane All outcomes

  2 days
  MD 0.89 [0.77, 1.01]
  1 study · 37 participants
  Very low

Xylitol (low-intensity sweetener/sugar alcohol) in food products (chewing gum, milk, candy, or tablets) vs no intervention

Xylitol significantly reduced Mutans streptococci in dental plaque compared with no treatment (SMD -0.73, 95% CI -1.09 to -0.37; 5 trials, I2=53%; not GRADE-rated).

• Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. 2024 All outcomes

  Post-consumption endpoint (trial durations 2 wk to 6 mo) · All age groups, generally healthy; multiple countries; sugar substitutes delivered as chewing gum, milk, candy, or tablets · Xylitol gum vs no treatment (5 studies, mixed ages)
  SMD -0.73 [-1.09, -0.37]
  5 studies · 308 participants
  GRADE not reported

Chlorhexidine chewing gum vs Placebo or no intervention (including routine care)

The review found no eligible studies for this question.

• Chlorhexidine treatment for the prevention of dental caries in children and adolescents 2015 · Cochrane All outcomes
  There were no trials on other products containing chlorhexidine such as sprays, toothpastes, chewing gums or mouthrinses.
  0 studies
  No studies found

Consumption of xylitol chewing gum by women (mothers) vs Profylin lozenge (xylitol/sorbitol + CMC)

• Interventions for the management of dry mouth: topical therapies 2011 · Cochrane All outcomes
  Patients ranked gum and lozenge equal for preference.
  1 study · 18 participants
  GRADE not reported

Consumption of xylitol chewing gum by women (mothers) vs Profylin lozenge (xylitol/sorbitol + CMC)

• Interventions for the management of dry mouth: topical therapies 2011 · Cochrane All outcomes
  No change in stimulated whole saliva.
  1 study · 18 participants
  GRADE not reported

Consumption of xylitol chewing gum by women (mothers) vs Profylin lozenge (xylitol/sorbitol + CMC)

• Interventions for the management of dry mouth: topical therapies 2011 · Cochrane All outcomes
  Risheim 1993 (crossover, high risk of bias, n=18, rheumatic patients): both products gave good subjective relief of dry mouth in slightly less than one third of participants; crossover design not accounted for, no…
  1 study · 18 participants
  GRADE not reported

Gum chewing (sugar-free) vs Within-subject before/after comparison of soft gum vs hard gum (no no-gum control)

One small study found that chewing hard (but not soft) gum increased oral mucosal moisture.

• The effect of gum chewing on xerostomia and salivary flow rate in elderly and medically compromised subjects: a… 2023 All outcomes

  2-week chewing period (soft then hard gum, with 2-week wash-out) · Haemodialysis units, elderly / geriatric care, cancer and palliative care, and xerostomia / hyposalivation clinics (studies from multiple countries)
  Single study [22] (Nakagawa 2017): chewing hard gum significantly increased oral mucosal moisture whereas chewing soft gum did not.
  1 study · 12 participants
  GRADE not reported

Chlorhexidine and xylitol chewing gum vs placebo (2‐week intervention)

No infant caries outcomes were assessed because the proposed randomized trial was discontinued.

• Reducing Alaska Native paediatric oral health disparities: a systematic review of oral health interventions and a case… 2013 All outcomes

  Yukon-Kuskokwim Delta · Trial discontinued
  no estimate extracted
  1 study
  GRADE not reported

Chewing gum vs Saliva substitute spray

Chewing gum (mechanical saliva stimulant) showed no clear difference in xerostomia (mouth dryness, VAS/scale) compared with saliva substitute spray; GRADE not reported.

• Interventions for the management of dry mouth: topical therapies 2011 · Cochrane All outcomes
  SMD -0.11 [-0.33, 0.11]
  2 studies
  GRADE not reported

Chewing gum vs Saliva substitute spray

Chewing gum (mechanical saliva stimulant) showed no clear difference in salivary flow (unstimulated whole saliva) compared with saliva substitute spray; GRADE not reported.

• Interventions for the management of dry mouth: topical therapies 2011 · Cochrane All outcomes
  MD 0.01 [-0.01, 0.04]
  2 studies
  GRADE not reported

Chewing gum vs Saliva substitute spray

Chewing gum (mechanical saliva stimulant) led to lower patient preference compared with saliva substitute spray; GRADE not reported.

• Interventions for the management of dry mouth: topical therapies 2011 · Cochrane All outcomes
  Bots 2005: statistically significant preference for chewing gum over Xialine spray, 39/49 (80%) preferred gum vs 10/49 (20%) spray (Chi2 17.16, df=1; P < 0.001) (Analysis 2.3). Davies 2000: more people preferred gum,…
  1 study · 65 participants
  GRADE not reported

Various saliva stimulants (chewable tablet, lozenges, chewing gum, CMC mouthrinse/sprays; 8-arm) vs Saliva substitutes / other products

• Interventions for the management of dry mouth: topical therapies 2011 · Cochrane All outcomes
  No product had a long-term effect on stimulated whole saliva production.
  1 study · 106 participants
  GRADE not reported

Various saliva stimulants (chewable tablet, lozenges, chewing gum, CMC mouthrinse/sprays; 8-arm) vs Saliva substitutes / other products

• Interventions for the management of dry mouth: topical therapies 2011 · Cochrane All outcomes
  Bjornstrom 1990 (8-arm crossover, high risk of bias, 106 enrolled, 55 used all 8 products): all products relieved dry mouth and difficulty talking/swallowing 'to some extent'; V6 chewing gum and Salivin lozenge ranked…
  1 study · 106 participants
  GRADE not reported

Xylitol (low-intensity sweetener/sugar alcohol) in food products (chewing gum, milk, candy, or tablets) vs Sorbitol (low-intensity sweetener)

Xylitol and sorbitol did not differ significantly for Mutans streptococci in saliva (SMD -0.16, 95% CI -0.44 to 0.12; 2 trials, P=.25); not GRADE-rated.

• Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. 2024 All outcomes

  Post-consumption endpoint (varied durations across trials) · All age groups, generally healthy; multiple countries; sugar substitutes delivered as chewing gum, milk, candy, or tablets · Xylitol gum vs sorbitol gum (2 studies)
  SMD -0.16 [-0.44, 0.12]
  2 studies · 201 participants
  GRADE not reported

Xylitol (low-intensity sweetener/sugar alcohol) in food products (chewing gum, milk, candy, or tablets) vs Sorbitol (low-intensity sweetener)

Xylitol reduced Mutans streptococci in dental plaque more than sorbitol (SMD -0.45, 95% CI -0.69 to -0.21; 4 trials, I2=7%); not GRADE-rated.

• Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. 2024 All outcomes

  Post-consumption endpoint (varied durations across trials) · All age groups, generally healthy; multiple countries; sugar substitutes delivered as chewing gum, milk, candy, or tablets · Xylitol vs sorbitol (4 studies)
  SMD -0.45 [-0.69, -0.21]
  4 studies · 323 participants
  GRADE not reported

Intervention not reported

• A Systematic Review and Meta-Analysis of the Role of Sugar-Free Chewing Gum on Plaque Quantity in the Oral Cavity. 2022 All outcomes
  No adverse events reported
  8 studies
  GRADE not reported