Yes, they may. There are various reasons why veneers break off and fall off or get damaged. Here are some of them:

Age of veneers – The primary reason is the age of the veneers. Porcelain veneers should last at least 10 – 15+ years. But conservatively speaking, veneer lasts for more than 15 years. As time passes, the veneers get slowly detached from the teeth as the adhesive bonding gets weakened over a period of time, making the veneers come loose and fall off.

Poor adhesive – The second most common reason is that the bonding agent used for the veneer to stick on teeth was not of prime quality in the first place. Either enough time was given for adhesive bonding to take place, or the technique was not proper. In either, it is a problem of the dentist, not of veneers.

Tooth decay – The other common reason is when the teeth on which veneers are placed get decayed. There are many reasons for tooth decay. It happens because of lifestyle choices and, in some cases, because of the effects of prescription drugs that some individuals cannot escape.

Teeth grinding – One more common reason is the patients’ habit of grinding teeth during sleep, or bruxism, for either physical or psychological reasons. If bruxism occurs regularly, the force on veneers is great. Veneers cannot hold up to the pressure on the inside edge and may chip, break, or get damaged.

Lack of proper care – Negligence is another common reason veneers fall or break off. Veneers are delicate devices which require good oral care. If they receive harsh treatment from the wearer, like chewing hard foods very often or grinding teeth, they show in breakage or falling off from the mouth.