If you read this blog — or any sexual health website, really — you’ll probably see dental dams getting a lot of props. A dental dam (not to be confused with a female condom) is a square piece of latex that can cover the vaginal opening or the anus. Anyone wishing to avoid the oral transmission of STDs like herpes, gonorrhea, HPV, syphilis, chlamydia, and intestinal parasites, dental-dam advocates say, should use a latex barrier. Most people, however, have probably never even seen a dental dam, and they are not widely used. Perhaps their unpopularity is related to myths about oral sex being safe sex (it’s not!); perhaps it’s due to dental dams being expensive or difficult to find.
Plastic wrap hasn’t been evaluated by the FDA for STD prevention, and no studies have assessed its effectiveness in reducing disease risk during oral sex.
Some safer-sex aficionados have found ways around that, though. They might cut the tips off of condoms and make incisions along the sides, creating little latex rectangles. An even easier and cheaper option lies in plastic wrap, which many people use as a barrier while performing cunnilingus (oral contact with the female genitalia) or rimming (oral contact with the anus). It is inexpensive, easy to find, odorless, and tasteless, and can be purchased without even a hint of embarrassment (unless perhaps your other purchases include duct tape, cucumbers, and clothes pins). And it can be pulled off the roll in sheets as long as your heart desires!
Planned Parenthood endorses the use of plastic wrap for oral sex when dental dams aren’t available. The Centers for Disease Control and Prevention and AIDS.gov both recommend plastic wrap for use during rimming. Health authorities, such as AIDS.gov and the Idaho Department of Health & Welfare, recommend non-microwavable Saran Wrap, because microwave-safe Saran Wrap has tiny pores to let out steam — which might also let viruses and bacteria through.
As you can probably guess, dental dams are formulated for dental procedures, not for sexual pleasure, and as such, some people find them to be too small and thick to be acceptable. The Sheer Glyde Dam, on the other hand, was designed specifically with oral sex in mind, and is the only barrier that is FDA-approved especially for oral sex. Plastic wrap, however, was designed for food storage, and is not FDA-approved to prevent the transmission of pathogens during sexual activity — manufacturers don’t even test it for that purpose. So what data do we actually have on the effectiveness of plastic wrap for preventing STD transmission?
A PubMed search barely turns up any scientific studies on STD prevention and dental dams, and information on plastic wrap is even more sparse. Probably the best piece was published in 2010, and while it focuses on dental dams, the authors do point out that plastic wrap “is likely to be effective simply because it is waterproof.” But laboratory evidence, according to the authors, is lacking, and we’re just not sure how permeable plastic wrap might be to sexually transmitted pathogens.
Dental dams and plastic wrap as safer-sex accessories are difficult to study. Human studies would have to enroll many couples in which one partner has an STD, such as HIV or genital herpes, and the other partner does not. Then, they would have to restrict their sexual repertoire to cunnilingus to ensure that disease transmission didn’t arise from other types of sexual contact. Couples would have to record how often they used protection during cunnilingus so researchers could look for a correlation between frequency of barrier use and probability of disease transmission. In case it needs to be said, such a study wouldn’t be easy to carry out!
Some dental-dam boosters have cited a few studies as evidence that plastic wrap can protect users from STDs. However, a closer look reveals that these studies’ results might not be applicable to plastic wrap when used as a dental dam.
- A 1986 study tested multiple plastic wrap varieties available at the time, and did not find them to be permeable to E. coli bacteria. However, the researchers just let the bacteria sit there, and weren’t subjecting the plastic wrap to any kind of vigorous activity as one might do during cunnilingus.
- A 1989 study did not find Glad Wrap to be permeable to the virus that causes genital herpes. The tests they performed involved moving a plunger up and down into a syringe, which is mechanically different from performing cunnilingus but at least more vigorous than letting the pathogens just sit there.
- Two studies, one from 2003 and another from 2004, examined whether plastic wrap could be used to cover a probe in order to protect patients’ eyes from the prions that cause Creutzfeldt-Jakob disease. However, neither study actually assessed the plastic’s permeability to prions — they merely examined whether or not the wrap interfered with the probes’ abilities to take accurate measurements.
- A 2008 study hypothesized that gloves made out of low-density polyethylene, the same material that Saran Wrap is made of, would protect health-care workers when helping HIV-positive mothers during birth. However, the gloves they made were first irradiated, which made them stronger. Second, the polyethylene was around five times as thick as regular plastic wrap. Lastly, the researchers didn’t actually inspect the gloves for permeability to HIV or other viruses — they were mostly interested in how to sterilize them without weakening the material.
Most important, none of these studies examined the use of plastic wrap in a sexual context. While using plastic wrap is surely much better than using nothing, its effectiveness is a question that is currently only being answered by a large, silent gap in the scientific research.
If you are considering a barrier method for cunnilingus or rimming, here are some helpful tips:
- If using a dental dam, wash away any powder that it may have been packed with, as it might lead to infections.
- The performing partner can hold the bottom two corners of the dam, while the receiving partner can hold the top two corners snugly against the body.
- If cutting a condom to make a dental dam, be careful not to poke holes in the latex with your scissors.
- Female condoms might not be a good choice as starting material for DIY dental dams: They may be coated with a silicon-based lubricant, which might irritate the receiving partner’s vaginal tissues, or lead to gastrointestinal symptoms if the performing partner ingests it in large amounts. (And, FYI, silicon-based lubricants might damage silicon sex toys.)
- Never reuse barriers, and don’t switch from the anus to the genitals (or vice versa) without changing dams first.
Sheer Glyde Dams and dental dams can be purchased at sex shops or online. You might also be able to find them at student health centers or LGBTQ community centers. While they are not carried by Planned Parenthood Arizona health centers, affiliates in other states might make them available to customers — call first to find out. In a pinch, you can improvise a dental dam out of a male condom. Non-microwaveable plastic wrap, of course, is widely available in grocery stores, and while it might offer protection against STDs, it wasn’t manufactured for that purpose and hasn’t been evaluated for effectiveness by the FDA.
Click here to check out other installments of our monthly STD Awareness series!