Ostomy and Convexity

Ostomy bags with convexity refers to the outward faceplate of skin for maximum seal. The convexity is defined as an upward bell shape into the skin. 

Why Convexity in Ostomy appliances?
Uneven seals, weirds shapes, and even leaks are somewhat common in the peristomal skin of ostomy appliances. A convexity introduced into the skin adds a stronger seal. The resulting outward curve means the ostomy bag is pressed firmly into the peristomal skin for the best seal possible.

Convex ostomy bags do not have a clear or single inventor. Rather, the convex shape is more so a trend in the ostomy industry. In the late 1980s and early 1990's, manfuactorers began to expriment with additional seals, adhesives, rings, and shapes for those with irregular body shapes or poorly contrsucted stomas. During this time, several manufacturers began to release products with convex skin barriers capable of use for 1 and 2 piece systems.

What is a convex pouching system? 

Flat pouching systems lay flat on the stomach around a stoma. Comparatively, the convex punching system differs in that it faces outward towards the skin. This is accomplished by the use of skin barriers, faceplate, ring(s), or some combination thereof. This means the stoma sticks out better and empties more efficiently into the punching system.

You may still be wondering what exactly this convex shapes means in terms of advantages. It means urine and leakages happen less often. It also means you can feel more secure, and your skin is irritated less often.

Convex products should also be used in some specific scenarios and may not be for everyone. For instance, if you have common leaks, then you should consider getting a consultation for a convex-shaped system. A convex shape can also be used to increase wear time due to the increased comfort and conforming style of the convex shape.

Different types of convex systems.

• There are several different types of convex system which vary according to material, method of sizing, and method of producing the convex shape.
• First up, there are "fit-to-convex" systems that allow for cutting the barrier to the specific fit of the stoma. This is especially helpful if your stoma is not round. This method also is used for one or two pouch systems. 
• Secondly, there is the pre-cut convex system that uses a precut shape and style. These often come in many different options for all sorts of stoma shapes and needs. The advantage here is that the barrier is already designed for you and reduces the needed time and energy to find a perfect fit. The disadvantage then is, of course, this style may not be an ideal fit like you can achieve with the "fit-to-voices" system. 
• Finally, a convex insert is a series of pre-cut rings for use in a two pouch system. These rings can be useful for people who want a system with increased support and rigidity. Otherwise, there are also ostomy belts and girders that provide additional support around the barrier as well.