The apex is the tip of the tooth’s root. On the apex, there is an opening called apical foramina. That is the place where all the blood vessels and nerves come inside the tooth.
Apex is a very commonly used term in dentistry. A lot of patients are not aware of what it means. It comes from the word apexes which means tip; the pointed end of a conical part; the top of a body, organ or part. The tooth is made of several parts, including a crown, root, neck. The apex is located on the tip of the root, or on the pointed end of it. Different teeth have a different number of roots. For example, the incisors have only one root and one apex. Teeth that have two roots have two apexes and so on.
When it comes to the anatomy of an apex, it is important to know that it features an important opening or several openings. It is called apical foramen or apical foramina. This is a small opening where the dental blood, nerve, and lymph vessels use to enter the pulp. In some cases, one apex can include several smaller foramina. This means that the largest one will be the main one, and all of the surrounding ones are considered as accessory canals. They are separated by dentin or in some cases by cementum. The apical foramen is the opening that connects teeth to the surrounding periodontal tissue. If the blood and nerve tissues are disconnected, then the tooth will not be vital anymore. The apical foramen usually has a size of around 0.3 mm in diameter.
The apex is commonly mentioned in endodontics. If you are getting a root canal, then it means that the dentist is working on the canal located in the roots, which finishes with an apical foramen on the apex. As mentioned, all of the nerve, blood and lymph vessels enter the tooth through this foramen. If the dental pulp is affected by inflammation or necrosis, the dentist has to perform a root canal procedure. This means that he has to completely remove all the remaining pulp tissue from the crown and from the root canal or canals depending on the tooth. The first thing he does is to enter the pulp, by forming a cavity. The following step is to remove the pulp in the coronal part. Later, they have to locate the entrance of the canal or canals. Dentists use special instruments to enter the canal and properly remove all the necrotic tissue. They have to exactly know where the apical foramen is located and finish there with the procedure. Sometimes it can be really hard to locate this foramen, so dentists use special techniques, including x-rays, and apex locators that help them in the process. Once they locate it, they clean everything and prepare the canals for filling. They fill them and seal them so that there is no contact with the surrounding periodontal tissue and to avoid another inflammation. There are teeth that finish with two or more foramina, which makes it very hard to achieve a good root canal procedure.