What a dental dam is
A dental dam is a soft, thin sheet, usually about 15 cm square, made of latex or polyurethane. It is placed over the vulva or anus during oral sex so there is no direct contact between mouth and genitals.
The name comes from dentistry, where similar sheets are used to isolate a tooth. Sexual-health dams are thinner and often flavoured.
Why use one
Oral sex can pass on infections including herpes, gonorrhoea, chlamydia, syphilis and HPV. A dental dam lowers that risk in the same way a condom does for other kinds of sex, and is recommended for oral sex on the vulva or anus, especially with new or casual partners.
Regular testing matters too; our guide to sexual health clinics and STI testing explains how to get tested free in the UK.
How to use one
Check the packet date, open it carefully and lay the dam flat over the area before any oral contact. Hold it in place with your hands and keep the same side facing the body throughout. Use a new dam for each act and each partner, and never turn it over or reuse it.
A little water-based lube on the body side can make it feel better; our lube guide explains which types are safe with latex. Avoid oil-based products, which weaken latex.
Where to get one, or make one
Many NHS sexual health clinics and C-Card schemes give dental dams out free. You can also buy them from pharmacies, online and in many sex shops.
In a pinch, you can make one from a condom: cut off the tip and the ring, then cut down one side and open it into a rectangle. Our guide on how to use a condom covers condom basics.
Your questions, answered
What is a dental dam used for?
It is a barrier placed over the vulva or anus during oral sex to lower the risk of passing on sexually transmitted infections.
Can you get dental dams free in the UK?
Often, yes. Many NHS sexual health clinics and C-Card schemes give them out free, and they are sold cheaply in pharmacies and online.
Can I make a dental dam from a condom?
Yes. Cut off the tip and the ring, cut down one side and open it flat. Use a non-lubricated condom if you can.
