- When a rubber dam is used to isolate teeth instead of cotton rolls, tooth repairs may be more likely to remain in place and be in good condition after six months.
- We need to conduct more studies in this area, to strengthen the evidence. These studies need to use robust methods, follow people beyond six months, and investigate adverse (unwanted) effects and costs.
Why do we isolate teeth when they are being repaired?
When dental practitioners need to repair a tooth, they often isolate it from the rest of the mouth to:
- keep away saliva to prevent it from impairing the bonding of materials;
- reduce aerosols produced during the dental procedure to a certain extent;
- stop materials, liquids or instruments used for the repair from being swallowed or damaging the mouth.
What do dental practitioners use to isolate teeth?
A common method for isolating teeth from the rest of the mouth is to use cotton rolls and a straw-like tube that sucks up saliva. This technique uses simple, inexpensive equipment, but requires frequent replacement of sodden cotton rolls.
An alternative option is to use a thin sheet of rubber (rubber dam). First, the dental practitioner makes a small hole in the sheet. They then place it over the tooth to be treated, creating a barrier around it. The sheet can be held in place with several methods, such as clasps placed over the tooth or a small piece of rubber wedged between teeth.
What did we want to find out?
We wanted to find out if rubber dams improve the success of tooth repairs when compared against other methods for isolating teeth. We also wanted to know if they are associated with unwanted (adverse) effects.
What did we do?
We searched for studies that compared using a rubber dam against another method for isolating teeth. We compared and summarized the results of these studies and rated our confidence in the evidence, based on factors such as study methods and sizes.
What did we find?
We found six studies that involved 1342 people in total (mostly children). Teeth needed repairing for a range of reasons, including caries (holes in teeth created by bacteria) and loss of hard tissue at the base of teeth. The studies compared rubber dams against:
- cotton rolls (five studies); and
- the Isolite system (a new method that combines plastic blocks, a shield for the tongue and cheek, and a tube that sucks up saliva and other mouth contents) (one study).
Rubber dam compared against cotton rolls
The evidence suggests that when a rubber dam is used rather than cotton rolls, tooth repairs may be more likely to remain in place and be in good condition after six months (2 studies). There is not enough robust evidence for us to determine if this is the case beyond six months.
Rubber dam compared against the Isolite system
The evidence is not robust enough for us to determine if using a rubber dam improves the success of tooth repairs when compared against the Isolite system.
No study investigated side effects.
What are the limitations of the evidence?
The evidence is based on a small number of studies conducted in ways that may have introduced errors into their results.
How up to date is this evidence?
The evidence is up to date to January 2021.
This review found some low-certainty evidence that the use of rubber dam in dental direct restorative treatments may lead to a lower failure rate of the restorations compared with cotton roll usage after six months. At other time points, the evidence is very uncertain. Further high-quality research evaluating the effects of rubber dam usage on different types of restorative treatments is required.
The effective control of moisture and microbes is necessary for the success of restoration procedures. The rubber dam, as an isolation method, has been widely used in dental restorative treatments. The effects of rubber dam usage on the longevity and quality of dental restorations still require evidence-based discussion. This review compares the effects of rubber dam with other isolation methods in dental restorative treatments. This is an update of the Cochrane Review first published in 2016.
To assess the effects of rubber dam isolation compared with other types of isolation used for direct and indirect restorative treatments in dental patients.
Cochrane Oral Health's Information specialist searched the following electronic databases: Cochrane Oral Health's Trials Register (searched 13 January 2021), Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 12) in the Cochrane Library (searched 13 January 2021), MEDLINE Ovid (1946 to 13 January 2021), Embase Ovid (1980 to 13 January 2021), LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 13 January 2021), and SciELO BIREME Virtual Health Library (1998 to 13 January 2021). We also searched Chinese BioMedical Literature Database (CBM, in Chinese) (1978 to 13 January 2021), VIP database (in Chinese) (1989 to 13 January 2021), and China National Knowledge Infrastructure (CNKI, in Chinese) (1994 to 13 January 2021). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform, OpenGrey, and Sciencepaper Online (in Chinese) for ongoing trials. There were no restrictions on the language or date of publication when searching the electronic databases.
We included randomised controlled trials (including split-mouth trials) over one month in length assessing the effects of rubber dam compared with alternative isolation methods for dental restorative treatments.
Two review authors independently screened the results of the electronic searches, extracted data, and assessed the risk of bias of the included studies. Disagreement was resolved by discussion. We strictly followed Cochrane's statistical guidelines and assessed the certainty of the evidence using GRADE.
We included six studies conducted worldwide between 2010 and 2015 involving a total of 1342 participants (of which 233 participants were lost to follow-up). All the included studies were at high risk of bias.
Five studies compared rubber dam with traditional cotton rolls isolation. One study was excluded from the analysis due to inconsistencies in the presented data. Of the four remaining trials, three reported survival rates of the restorations with a minimum follow-up of six months. Pooled results from two studies involving 192 participants indicated that the use of rubber dam isolation may increase the survival rates of direct composite restorations of non-carious cervical lesions (NCCLs) at six months (odds ratio (OR) 2.29, 95% confidence interval (CI) 1.05 to 4.99; low-certainty evidence). However, the use of rubber dam in NCCLs composite restorations may have little to no effect on the survival rates of the restorations compared to cotton rolls at 12 months (OR 1.38, 95% CI 0.45 to 4.28; 1 study, 30 participants; very low-certainty evidence) and at 18 months (OR 1.00, 95% CI 0.45 to 2.25; 1 study, 30 participants; very low-certainty evidence) but the evidence is very uncertain. At 24 months, the use of rubber dam may decrease the risk of failure of the restorations in children undergoing proximal atraumatic restorative treatment in primary molars but the evidence is very uncertain (hazard ratio (HR) 0.80, 95% CI 0.66 to 0.97; 1 study, 559 participants; very low-certainty evidence).
None of the included studies mentioned adverse effects or reported the direct cost of the treatment.