Introduction
Root filling is the final step of a root canal treatment and seals the canals of the tooth against bacteria. Especially the first days after the root canal filling, the affected tooth can be painful, because the procedure causes some irritation to the tooth. But where does this pain come from and how long does it last? Do I have to worry that the pain is a sign that the root filling has failed?
Causes of pain after root canal filling
First of all, a slight pain in the first days after a root canal filling should not be a cause for concern, because the procedure itself is always associated with a certain irritation of the tooth. The insertion of the root filling and the subsequent pressing and squeezing can cause this pain. The dentist informs the patient that the tooth may cause pain in the first days after the treatment and that this is not a sign of a failed therapy.
However, these complaints usually subside completely after one to two weeks. If the symptoms persist, this could indicate that bacteria have remained in the canal system. If the root tip is not flushed sufficiently or if there are massive areas of inflammation at the root tip, inflammatory cells and bacteria that cause pain may remain even after filling. The bacteria produce antigens and toxins, which can only escape downwards through the closed root filling and thus trigger an inflammatory reaction.
Why does pain occur?
The pain after a completed root filling can be caused by various factors.
- The definitive root filling was placed at the wrong time: an inflammation below the root tip, apical periodontitis, requires a longer healing time. First of all, a temporary medication is placed in the root canals, which has an antibacterial and pain-relieving effect.
This medication is changed several times by the dentist until the inflammation has subsided. Only then the definitive filling of the root canals takes place. If the process is stopped prematurely so that a definitive root filling is placed, although the tissue around the root tip has not healed, the bacteria in the canal are trapped, so to speak.
This allows the inflammation to spread after the root canal filling has been placed and infiltrate further tissue, making the symptoms even worse.
- The root filling is too short, blistery, not walltight: bacteria can still penetrate the root canal and cause inflammation and pain.
- The root filling is too long: if the root filling material protrudes beyond the root tip, the surrounding tissue is irritated and may regress with inflammation to break down the foreign material. This is especially dangerous in the upper jaw, because due to the close positional relationship to the maxillary sinus, an excessively long root filling can protrude into the maxillary sinus and cause an inflammation there.
- The tooth breaks or is split: A longitudinal or transverse fracture after a root canal filling is always a possible complication that causes bacteria to enter the canal system through the fracture gap and the patient suffers severe pain. The consequence of a fractured tooth is always an extraction of the tooth in case of a longitudinal fracture or a very deep transverse fracture.
In the case of transverse fractures in the area of the crown of the tooth above the gum, the tooth can still be stabilized with a pin and a crown in individual cases.
- The filling is too high: the opening of the tooth during root canal filling is closed either by temporary or permanent filling material, depending on whether it is a drug insert or the definitive root filling. If this filling is too high, then the increased chewing pressure on the tooth creates another stimulus on the root tip and pain occurs.
An overfilled root filling describes the phenomenon that during a root filling, the sealer that seals the part between the filling material and the canal walls overpresses. If too much sealer is introduced into the canal with an increased amount, the sealer is pressed beyond the root tip and thus reaches the surrounding tissue.
In the USA this is considered desirable by dentists because it ensures that the filling is sealed and reaches the root tip. In Europe, the treatment goal is defined in such a way that the filling should be exactly at the tip of the root. This becomes visible in the radiological control image after the root filling.
Therapeutically, we wait and see whether the tooth is still free of complaints despite the overpressed material.The sealer can be broken down by the body’s immune cells. If this is the case, the condition can be left as it is. However, if the symptoms persist or become worse after the root canal filling, the overpressed material must be removed from the tissue by a root tip resection.
