What do systematic reviews say?

Experimental chewing adjuncts (bite wafers or chewing gum) vs No chewing gum, placebo, or control (no adjunct)

Experimental chewing adjuncts (bite wafers or chewing gum) led to lower quality of life or patient satisfaction compared with no chewing gum, placebo, or control (no adjunct); GRADE not reported.

• Non‐pharmacological interventions for alleviating pain during orthodontic treatment 2016 · Cochrane All outcomes

  24 hours
  RR 0.45 [0.22, 0.94]
  2 studies · 107 participants
  GRADE not reported

Chlorhexidine gel (0.12%) vs no treatment

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
  Neither of these trials reported on the other secondary outcomes such as measures of pain, quality of life, patient satisfaction or direct and indirect costs of interventions.
  0 studies
  No studies found

Chlorhexidine varnish vs placebo or no treatment

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
  No trials reported on pain, quality of life, patient satisfaction or costs.
  0 studies
  No studies found

Ball (stud) attachment system vs Bar attachment system

• Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws 2018 · Cochrane All outcomes
  Only Walton 2002 assessed patient satisfaction but reported narrative results and failed to provide any usable numbers. Quality of life as assessed by a validated measure was not recorded in any of the trials.
  1 study
  GRADE not reported

Ball (stud) attachment system vs Telescopic attachment system

• Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws 2018 · Cochrane All outcomes
  Cepa 2017 assessed patient satisfaction but did not use validated measures and we could not use the data. Quality of life as assessed by a validated measure was not recorded.
  1 study
  GRADE not reported

Ball (stud) attachment system vs Magnetic attachment system

• Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws 2018 · Cochrane All outcomes
  Two trials (Cune 2010; Naert 1999) reported patient satisfaction. However, we could not use any data from these studies. Quality of life as assessed by a validated measure was not recorded in any of the trials.
  2 studies
  GRADE not reported

Single full-coverage metal-ceramic crown over composite core and post vs Direct adhesive composite restoration with post (conventional filling, no crown)

The review found no eligible studies for this question.

• Single crowns versus conventional fillings for the restoration of root‐filled teeth 2015 · Cochrane All outcomes
  This outcome was not reported nor measured by the study. The abstract confirms no evidence was available for any secondary outcome.
  Studies not reported
  No studies found