Not all mouth tape is the same shape, and the shape is not just cosmetic — it changes how securely the tape seals and how it feels. Walk through the options once and the choice gets easy. (The full mouth tape guide is here.)
The horizontal full strip
The classic and the one I recommend for most people: a single strip placed horizontally across closed lips, sealing them together edge to edge. It holds the whole mouth shut, which is exactly the job. A good full strip is the most reliable seal because there is no gap for your mouth to open around during deep sleep.
Pros: most secure, simplest to apply. Cons: the most "sealed" feeling, which is the bit new users adapt to over the first few nights.
The vented strip (a hole in the middle)
Some strips include a small vent or hole in the center, marketed as a gentler, more reassuring option — you can always breathe through the gap. That reassurance is also the catch. The whole point of taping is to stop mouth breathing; a built-in hole is an escape hatch your mouth will use during deep sleep without waking you, quietly undoing the benefit. You end up mouth-breathing through the vent and wondering why the dry mouth never went away.
Pros: feels less restrictive, easier first-night psychology. Cons: defeats its own purpose for the people who most need a full seal. I would rather someone start with a small full strip they can breathe around the edges of than a vented one that lets them mouth-breathe all night. This is also why the tape I use — Titan Recovery's bamboo silk mouth tape — is a deliberate full strip with no center vent.
The X-shape (two crossed strips)
Two strips crossed over the center of the lips, leaving the corners of the mouth freer. A middle ground: it holds the center sealed while feeling less total than a full strip, and the open corners give a little psychological give.
Pros: a compromise between security and comfort. Cons: more fiddly to apply, and less of a complete seal than a full strip.
The single dot
One small patch over the very center of the lips. The most minimal option — it nudges the lips together at the center while leaving most of the mouth untaped.
Pros: least restrictive, good for very anxious first-timers. Cons: the weakest seal by far; for a committed mouth breather it often is not enough to keep the mouth closed in deep sleep. Better as a training-wheels step than a long-term solution.
Which shape should you use?
For most people who genuinely mouth-breathe at night, a full horizontal strip is the right call — it is the only shape that reliably keeps the mouth closed all night, which is the entire point. If you are nervous, start with a small full strip you can breathe around the edges of rather than a vented one, because the vented and dot options trade away the actual benefit for a feeling of reassurance. (The first-night guide walks through easing in.)
The one shape to be skeptical of is the vented strip: a hole in the middle of a mouth tape is working against the reason you bought it. For more on why cheap and poorly-designed tapes fall short, see this.