Whether tooth structure has been lost due to breakage or cavities, if treatment is delayed, the problem just gets worse.
If the tooth breaks more, it’s going to be hard to fix, and there may be no choice but to extract the tooth. Unfortunatlely, an extraction is only a short-term solution. Teeth need each other for support. A missing tooth sets off a chain reaction of shifting teeth and other dental problems.
When treatment is delayed, cavities just get bigger and bigger. They grow slowly while still in the hard outer enamel. But if a cavity is allowed to reach the softer inner dentin, it grows much more quickly. Then the race is on to fill the cavity before it reaches the pulp chamber. If it reaches the pulp chamber, the tooth will require root canal treatment.
A filling may be an alternative, but fillings don’t add strength to the tooth. They simply fill in the damaged part of the tooth lost to decay. There has to be enough tooth to hold the filling in place and keep the tooth from breaking when you chew. Putting a crown on the tooth strengthens it and protects it from breaking.