Avoiding pulpal death during fixed prosthodontic procedures

Author: Dr. Nhan Tam View: 659
Broken, large chipped teeth or teeth with pulp problems should be carefully analyzed before making fixed restorations. If pulp survival is in doubt, endodontic treatment should be performed before restoration rather than fixed restoration and root canal therapy as needed.

Avoiding pulp death during fixed restorations is one of the challenges. In many discussions with dentists around the world, I have found that there are different views on the relationship between fixed restorations and endodontic treatment. Some dentists consider that they prefer endodontic treatment on all teeth that need fixed restorations, while others consider that endodontic treatment is rarely needed after fixing fixed restorations. It is true that there are some challenges when performing fixed restorations without endodontic treatment.

After years of fixing prosthetics, performing thousands of crowns, and talking to hundreds of dentists, I offer some personal observations that can help practicing dentists avoid treatment failure. endodontic after fixing fixed prosthesis.

Reconstruction of teeth can cause pulp trauma

Reconstruction is performed when there is a problem with the remaining structure of the tooth to support the fixed restoration and when a small portion of the tooth structure remains between the preparation surface and the pulp chamber.

Regenerating materials and bonding agents can stimulate pulp. The most popular dental tissue reconstruction material today is composite, but people still use amalgam. In order that the restorative material does not contribute to the consequences of endodontic treatment, I suggest bonding the self-erosion system before placing the composite or using 4-methacryloxyethyl trimellitic anhydride or 4 META as an amalgam sealant such as Amalgambond (Parkell, Farmingdade). , NY) before placing amalgam.

The pulp stimulation of cementitious

In recent times, cementitious cause irritation of the pulp is one of the most common causes of root canal treatment after fixing fixed prosthesis. However, reinforced resin glass ionomer cements such as RelyX Luting Cement (3M, St, Paul, Minn.) and Fuji Plus (GC America, Alsip, III.) have become the most commonly used mounting cements. in U.S.A. These are weak stimulant cements, significantly reducing the problem of tooth sensitivity after attachment, I suggest continuing and expanding the use of this cement.

Cutting tools

Some dentists use long-lasting cutting tools. For me, a disposable drill and a diamond bit costing about 1 USD are appropriate. This avoids unintended consequences of cutting when using expensive and reusable tools.

Dehydration in teeth

Preparation of teeth for permanent restorations removes most of the enamel leaving the dentin exposed and tends to lose a lot of water. For a good impression, the area to be impression must be dry and this tends to over-dry the tooth. Soft tissue protection and limited tooth drying have been suggested to avoid damage to the pulp by dehydration of the tooth.

Off-axis handpiece

Handpiece misalignment is a common problem when handpieces are used to grind a large number of tooth structures. After multiple hot sterilizations, the high-speed handpiece vibrates and the concentricity is reduced, causing a knocking impact on the tooth and creating the potential for pulp trauma. Dentists are advised to observe the concentricity of the rotary instrument in the handpiece. When detecting that the drill bit is not concentric, it is necessary to repair or replace the handpiece.

Pressure on cutting tool

The air-powered handpiece used for cutting should touch the teeth lightly. However, in some cases, large changes in sound indicate that cutting is being carried out with near-maximum pressure. When using a sharp rotary tool, just apply enough pressure to easily cut the tooth. If the rotary tool is worn or the concentricity of the handpiece is reduced, a great deal of pressure must be placed on the tooth grinding tool during service. This large cutting pressure causes heat generation and eccentricity of the cutting tool, creating strong impacts on the teeth.

The tooth is dead pulp before starting to do the restoration

Teeth with large restorations or teeth with pulp problems should be carefully analyzed before making fixed restorations. If pulp survival is in doubt, endodontic treatment should be performed prior to restoration rather than fixed restoration and root canal therapy as needed. In my opinion, many crowns are made on teeth with dead pulp or suspected teeth that have not received root canal treatment, in a few months or years these teeth will have symptoms and require endodontic treatment through the crown or restoration.

Stuck in the bite

Fixed restorations attached in the state of early touch will be sensitive abutment teeth and opposing teeth. I recommend careful evaluation of all fixed restorations prior to placement to determine if the occlusion is too high or too low with thin occlusal papers such as Accufilm 2 (Parkell) or Madaam Butterfly (Almore, Portland, Ore). . Novice doctors can make the mistake of accepting low-occlusal prostheses because the patient does not complain. The patient may accept a low-occlusal prosthesis for a day or two, but eventually the teeth adjacent to the newly fitted tooth will suffer from the added pressure and are at risk of fracture under this additional pressure.

Too much tooth preparation

Some doctors tend to grind a lot of tooth tissue when making fixed restorations. Although this makes the process of teeth whitening in the laboratory easier, it is dangerous for the pulp. It is advisable to grind the teeth as little as possible to the extent allowed to avoid damaging the pulp. This prophylaxis is especially necessary in young patients because of the large pulp chamber teeth.

Inappropriate water and steam pressure on teeth

Spraying too much water while grinding the teeth limits visibility, but spraying less water will generate heat affecting the pulp. From experience, I recommend a simple clinical guideline: if there is a grayish coating on the tooth during grinding, more water should be used. Water and steam can be supplied from the handpiece or from the auxiliary spray arm by the dental assistant for easy viewing.


As clinicians find that teeth with fixed restorations need more and more endodontic treatment, there are already many adverse factors contributing to pulp death. The ten adverse factors I have mentioned in this article are based on my observations over many years of fixed prosthetics, research, and discussions with other practitioners.