Special treatments for the pulp - Endodontics
Special treatments for the pulp
Indirect pulp covering
This is referred to as an indirect pulp covering when the dentist leaves some light-soaked dentin in the middle of the cavity. This can be a choice if the dentist expects that there is a good chance of exposure of the pulp. A layer of calcium hydroxide is applied to this slightly softened dentin layer. An indirect pulpa shelter is used for caries profunda where there is no question of spontaneous pain.
The method is as follows: after preparation and cleaning of the enamel dentin border, some softened dentin tissue is left in the center of the cavity. When the preparation is further ready, a thin layer of calcium hydroxide is applied and then a layer of cement. Finally, it is restored with a plastic or cast material. The purpose of this treatment is that calcium hydroxide stimulates odontoblasts to form new dentin (repair or irritation dentine).
Direct pulp cover
When removing caries profunda or due to a trauma, the pulp may become open, a pulp exponation. If the exponation is small and the patient had no complaints prior to treatment, a calcium hydroxide substrate can be applied to the open part of the pulp. We call this a direct covering. The purpose of this is to form a dentin bridge and to postpone or prevent an endodontic treatment.
The procedure is as follows: calcium hydroxide is applied to the pulp wound. Care must be taken that the entire wound surface is properly covered with calcium hydroxide. A cement is applied over this without pressure and finally the final restoration is made. It is advisable to check the element for vitality after six months and to take an X-ray (see image below).
a Indirect roof; b direct covering.
Treatment of the sensitive tooth neck
A sensitive tooth neck is caused by receding gums. The cause may be insufficient oral hygiene or scrubbing too hard with an abrasive toothpaste. Part of the root dentin will be exposed. This can give sensitivity to cold, heat, sweet, sour and touch. The frequent use of acidic foods (citrus fruits, carbonated soft drinks) can also lead to sensitive tooth necks.
The treatment consists of giving explanations and instructions to the patient. The patient can use a toothpaste with special ingredients (desensitizing toothpaste) which, with repeated use, reduces the sensitivity of the tooth neck after some time. The effect is based on covering the open dentine channels.
With severe sensitivity, the dentist can cover the exposed dentine with an application agent that contains fluoride or oxalate or a synthetic resin adhesive varnish. The effect of each of these substances is based on covering the dentine channels.
One speaks of a vital amputation if one removes the crown pulp from a vital element, but leaves the contents of the root pulp intact. The method is most commonly used with permanent front elements whose roots are not yet fully grown. The goal is that the element can continue to form. It usually concerns front elements in children, where the crown is fractured due to a trauma. The pulp has been widely exhibited and a direct pulp canopy is no longer possible.
A vital amputation is also applied to deeply carious (second) milk mills. The child may not have any complaints yet. The goal is to retain the element. As a result, the molars do not shift to mesial. Serious lack of space in the permanent teeth is thus prevented
The crown pulp is extracted, after which the root pulp is covered with calcium hydroxide. The intention is that the carrot pulp remains healthy, and that the carrot can continue to form. A cement is applied to the calcium hydroxide without pressure, followed by the final restoration (see image below).
Vital amputation at a milk molar. The root canal content consists of vital pulp tissue.
One speaks of vital extirpation when the contents of the root pulp are removed with the help of a special endone needle, the extirpation needle. This is applied to a pulpitis, or to trauma of a vital mature element.
The method is as follows: after opening the pulp chamber, the channel entrances are brought into view. The root pulp is removed with the help of an extirpation needle. The extirpation needle is a round needle with notches that act as a kind of barbs. The needle is introduced into the channel and by rotating it the barbs grasp the pulp tissue around the needle. The needle is then pulled out of the channel. This treatment is followed by the complete preparation and cleaning of the pulp cavity with closure, in the same session or later (see image below).
Extruded pulp with an extirpation needle.
Apexification is applied to permanent elements that have not yet been formed whose pulpa has become avital.
The aim is to allow the apex to form, after which a properly sealing root canal filling can be applied in the normal manner. The method consists of gently cleaning the still-wide pulp cavity with files up to 2 mm for the apex and filling with calcium hydroxide. Regular X-ray examinations are required. The cleaning and temporary filling may need to be repeated until the apex is closed.
Apexification can also be obtained by using MTA (mineral trioxide aggregate). This is a biocompatible cement that encourages dentin formation. A week after the channel is prepared and filled with calcium hydroxide, the channel is cleaned again. The MTA paste is applied to the apical part of the root (5 mm) and gently pressed. Because MTA cures slowly, a cotton ball and an emergency filling are applied and the final filling is made in a third session.
One speaks of drainage when a drain is made from an element to the outside world in order to drain off inflammatory moisture. Sometimes a natural drain is created for the inflammatory fluid, a fistula. Extraction of an element can also be a form of drainage. Here the first case is mentioned.
There is an indication if there is an acute periapical inflammation with the formation of a lot of inflammatory fluid. Increased pressure is created and the patient experiences severe pain. An opening is made through the root canal so that the moisture can flow away. This can provide relief from the pain.
The method is as follows: the element is opened into the pulp chamber. The apex is passed with the three smallest files and the channel is filed. We call this 'filing through the apex'.
Bleaching of an endodontically treated tooth
An element may discolor after a trauma or root canal treatment. This occurs because components of necrotic residues or used filling materials are absorbed from the pulp cavity into the dentine channels. This gray, blue or brown discolouration can be particularly disturbing with a front element. By bleaching the element from the pulp cavity, this discoloration can be (partially) eliminated.
The 'walking bleach' method is as follows:
- The filling in the endodontic opening is removed and the pulp chamber is completely emptied and cleaned with a round drill, up to 2 mm below the gingival level.
- The pulp chamber is etched to open the dentine canals.
- A little sodium perborate (granules) with water is made into a thick paste and enclosed in the pulp chamber by means of an emergency filling.
- After one to two weeks the patient returns and the result is viewed. The procedure may be repeated if necessary.
- When a satisfactory result has been achieved, the element is permanently filled (see image below).
Walking bleach method. a The endodontically treated 21 is discolored. b Result after treatment with sodium perborate and with a new restoration.
With root fractures there is a fracture of the element, involving dentin, cement and pulp. The root fracture can run horizontally or vertically.
Horizontal root fractures often occur after a blow, fall or blow. The height of the fracture line in the root surface and the way in which the recovery process proceeds determine the prognosis of the element.
A vertical root fracture can occur if an element is avital and a nodule wall breaks off quite far to cervical or if the element is overloaded.
If the fracture is in the apical one third of the root, an endodontic treatment can be performed in the upper two thirds. Possibly the apical part remains vital. Should the root point cause problems, it can be surgically removed by the MKA surgeon. The prognosis of fractures in the cervical two thirds of the root is very doubtful (see image below).
Root fracture after a trauma.