What do systematic reviews say?

Zinc supplements vs Acupuncture

The review found no eligible studies for this question.

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes
  Authors' conclusions: We were unable to draw any conclusions regarding the superiority of zinc supplements or acupuncture as none of the trials compared these interventions.
  0 studies
  No studies found

Zinc oxide and eugenol (ZOE) vs Zinc oxide and propolis (ZOP)

The review found no eligible studies for this question.

• Pulp treatment for extensive decay in primary teeth 2018 · Cochrane All outcomes
  Listed as a pulpectomy comparison; no extractable outcome data reported in this version
  0 studies
  No studies found

Zinc oxide and eugenol (ZOE) vs Ozonated sesame oil-zinc oxide (ZO)

The review found no eligible studies for this question.

• Pulp treatment for extensive decay in primary teeth 2018 · Cochrane All outcomes
  Listed as a pulpectomy comparison; no extractable outcome data reported in this version
  0 studies
  No studies found

0.2% zinc sulphate toothpaste vs Placebo toothpaste (without zinc)

0.2% zinc sulphate toothpaste led to lower volatile sulphur compounds (VSC) compared with placebo toothpaste (without zinc); GRADE not reported.

• Interventions for managing halitosis 2019 · Cochrane All outcomes

  4 weeks
  MD -11.3 [-20.45, -2.15]
  1 study · 188 participants
  GRADE not reported

0.2% zinc sulphate toothpaste vs Placebo toothpaste (without zinc)

It is very uncertain whether 0.2% zinc sulphate toothpaste changes dentist-reported organoleptic test (OLT) score (scale 0 to 5) compared with placebo toothpaste (without zinc) (very low certainty).

• Interventions for managing halitosis 2019 · Cochrane All outcomes

  mean 4 weeks
  MD -1.31 [-1.39, -1.23]
  1 study · 187 participants
  Very low

Zinc chloride + sodium chlorite mouthrinse (TriOral) vs Control mouthrinse (containing neither zinc chloride nor sodium chlorite)

• Mouthrinses for the treatment of halitosis 2008 · Cochrane All outcomes

  4 weeks
  Codipilly 2004: precise data could not be extracted (results presented as graph plots). Reported VSC reductions from baseline for zinc chloride + sodium chlorite (TriOral): 55% (P < 0.01) at 2 weeks and 60% (P < 0.01)…
  1 study
  GRADE not reported

Zinc chloride + sodium chlorite mouthrinse (TriOral) vs Control mouthrinse (containing neither zinc chloride nor sodium chlorite)

• Mouthrinses for the treatment of halitosis 2008 · Cochrane All outcomes

  4 weeks
  Codipilly 2004: only indirect surrogate salivary organoleptic scores were reported (not organoleptic breath scores); no accurate deductions could be made from the reported values.
  1 study
  GRADE not reported

Abrasive candy; abrasive candy + 2% propolis; abrasive candy + 0.5% zinc gluconate vs Abrasive candy + 1% propolis + 0.25% zinc

• Interventions for managing halitosis 2019 · Cochrane All outcomes
  Barak 2012 (5-arm RCT) compared abrasive candy, abrasive candy with propolis and abrasive candy with zinc gluconate versus abrasive candy with propolis and zinc; VSC measured by halimeter. We could not use the results…
  1 study
  GRADE not reported

Zinc vs placebo

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes
  Results: Matson 2003 used zinc sulphate for testing taste discrimination (sip and spit method); the trial did not report the details of the placebo group and thus the results could not be meta-analysed. Not GRADE-rated.
  1 study
  GRADE not reported

Zinc vs placebo

Zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate,… showed no clear difference in taste acuity improvement - objective outcome (continuous) -… compared with placebo; GRADE not reported.

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes

  Chronic renal failure
  Results (Mahajan 1980, chronic renal failure; Analysis 1.3): mean difference by taste sensation - salt MD 285 (95% CI 238.75 to 331.25); sweet MD 190 (142.36 to 237.64); sour MD 10 (-16.43 to 36.43); bitter MD 2.40…
  1 study · 22 participants
  GRADE not reported

Zinc vs placebo

It is very uncertain whether zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate,… changes taste acuity improvement - objective outcome (continuous) - taste… compared with placebo (very low certainty).

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes

  6 months · Children with chronic renal failure
  MD 2.50 [0.93, 4.07]
  1 study · 14 participants
  Very low

Zinc vs placebo

It is very uncertain whether zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate,… changes taste acuity improvement - patient-reported outcome compared with placebo (very low certainty).

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes

  Mean 3 months · Zinc-deficient/idiopathic taste disorder
  RR 1.40 [0.94, 2.09]
  2 studies · 119 participants
  Very low

Zinc vs placebo

It is very uncertain whether zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate,… changes taste acuity improvement - objective outcome (continuous) - taste… compared with placebo (very low certainty).

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes

  6 months · Children with chronic renal failure
  MD 3.00 [0.66, 5.34]
  1 study · 14 participants
  Very low

Zinc vs placebo

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes
  Results (health-related quality of life): None of the studies reported data on health-related quality of life. Heckmann 2005 (zinc) reported that signs of depression were less severe (Beck Depression Inventory P<0.05;…
  1 study
  GRADE not reported

Zinc vs placebo

Zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate,… led to higher taste acuity improvement - objective outcome (dichotomous) - chronic… compared with placebo; GRADE not reported.

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes

  Chronic renal failure
  RR 25 [1.65, 379.57]
  1 study · 24 participants
  GRADE not reported

Zinc vs placebo

It is very uncertain whether zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate,… changes taste acuity improvement - objective outcome (continuous data) compared with placebo (very low certainty).

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes

  Mean 3 months · Idiopathic dysgeusia
  SMD 0.44 [0.23, 0.65]
  3 studies · 366 participants
  Very low

Zinc vs placebo

It is very uncertain whether zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate,… changes adverse events compared with placebo (very low certainty).

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes

  12 to 18 weeks
  RR 5.20 [0.90, 30.19]
  3 studies · 335 participants
  Very low

Zinc vs placebo

It is very uncertain whether zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate,… changes taste acuity improvement - objective outcome (dichotomous data) compared with placebo (very low certainty).

• Interventions for managing taste disturbances 2017 · Cochrane All outcomes

  Mean 3 months · Idiopathic/zinc-deficient taste disorder
  RR 1.42 [1.09, 1.84]
  2 studies · 292 participants
  Very low

Zinc chloride without sodium chlorite mouthrinse (Breath Rx containing cetylpyridinium chloride) vs Control mouthrinse (containing neither zinc chloride nor sodium chlorite)

• Mouthrinses for the treatment of halitosis 2008 · Cochrane All outcomes

  4 weeks
  Codipilly 2004: reported VSC reduction from baseline for zinc chloride minus sodium chlorite (Breath Rx containing cetylpyridinium chloride): 38% (P < 0.05) at 2 weeks, versus a control containing neither zinc chloride…
  1 study
  GRADE not reported

Polaprezinc vs Azulene oral rinse

The review found no eligible studies for this question.

• Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy 2017 · Cochrane All outcomes
  No data on salivary flow rates were reported.
  0 studies
  No studies found