Temporary Cement: How These Materials Can Earn a Permanent Place in Your Inventory

Temporary Cement: How These Materials Can Earn a Permanent Place in Your Inventory. Image: © Dental Pro Content - stock.adobe.com

Restorative dentistry demands a lot from temporary cement. It should provide excellent retention to a substrate for a provisional restoration and disappear quickly when it's time to place the final prosthetic. We explore what you should look for in these materials for the best and most predictable performance.

Research indicates that temporary cement has 3 primary uses. It bonds provisional prostheses, bonds definitive prostheses temporarily, or attaches a prosthesis to an implant. Moreover, the temporary cement should:¹

• Provide sufficient prosthetic retention and a secure seal between the post and the restoration.
• Keep the seal intact despite changes in oral temperature
• Remain on the restoration rather than the tooth to make it easy to remove during debonding

Also, the dental tissues should tolerate the temporary cement well. It should also protect the prepared tooth and minimize sensitivity until the final restoration can be placed.²

Classifying Temporary Cements

Usually, dentistry classifies temporary cement based on its composition. These typically break down into 4 main categories:³

1. Zinc Oxide with Eugenol Cements (ZOE): ZOE cement contains eugenol that is effective at sedating the pulp and is antimicrobial. However, research emerged suggesting eugenol negatively influenced final cementation strength, which led to the development of zinc oxide temporary cement without eugenol.
2. Zinc Oxide without Eugenol Cements (ZONE): ZONE cement is eugenol-free and offers excellent retention but has no sedating or desensitizing effect.
3. Polycarboxylate Cement: Polycarboxylate cement adheres well to the tooth and offers excellent retention of provisionals but can be challenging to remove. 
4. Resin-based Cement: Resin-based cement offer excellent retention and better overall esthetics but can cause microleakage and sensitivity issues. Some newer resin cement has added potassium nitrate and chlorohexidine to help combat these issues.

However, their setting mechanism can also be used as a classification criterion. For example:¹

• Self-curing cement consists of a base and a catalyzer. When mixed, it sets on its own. Calcium hydroxide or zinc oxide is used in its composition.
• Dual-cure temporary cement light activates and comprises translucent resins, making them an aesthetically appealing option.

Choosing Between the Cements

Unfortunately, the answer to the question of which temporary cement is the one that should have a permanent place in your armamentarium is inconclusive. The consensus is that you should have a few options available for use in different situations. In other words, considering the properties of each type of cement material and the specific clinical situation when selecting the appropriate one for cementing a provisional restoration is essential to ensure the best outcome for the patient.

Factors such as the type of restoration, the tooth's location, and the tooth structure's condition are all considered when selecting a temporary cement. Spear Education encourages clinicians to consider the following 3 areas:³

Area #1

Tooth preparation: What is the retention and resistance situation?

To ensure the provisional stays in place, clinicians must evaluate whether the tooth preparation provides enough resistance. For example, cement becomes crucial to retention if the preparation is short or tapered. By contrast, clinicians can use adhesive with minimal retentive properties if the tooth has a lengthy preparation or mechanical retention, like inlays or onlays. Splinting multiple teeth together also increases retention. However, minimal preparation for veneers in the anterior segment provides little to no retention.

Area #2

Patient availability: How temporary will this provisional restoration be?

The duration of wear and patient availability are essential factors to consider when choosing suitable cement. If the patient cannot come in quickly or the treatment happens in phases, a durable adhesive is needed to keep the provisional in place and the preparation sealed. However, using retrievable cement works if the patient is returning soon. However, in cases involving dentin bonding, avoiding using a provisional that can harm the final cementation is essential.

Area #3:

Visibility: Will anyone see where the provisional is going to be?

For the anterior teeth that are visible during a patient's smile, it's crucial to consider the provisional cement's opacity, especially for conservative restorations. Opaque provisional cement can show through the temporary and compromise the esthetics. Therefore, it's essential to choose a provisional cement that's transparent or tooth-colored, which would blend well with the provisional restoration and mimic the natural tooth color. This will ensure that the patient is satisfied with their appearance and provide a better idea of the final restoration.

Nathaniel Lawson, DMD, PhD, assistant professor, and director of the Division of Biomaterials at the University of Alabama Birmingham School of Dentistry, has a similar take. He thinks temporary cement falls into 2 major types: ZONE and resin-based temporary adhesives.

Generally, Dr Lawson explains, ZONE cement is cheaper but less esthetic (white opaque) and less retentive. On the other hand, Dr Lawson says resin cement is more esthetic because it can be transparent or tooth-colored.

"Sometimes a ZONE cement will be visually apparent through a thin temporary or at the margin," Dr Lawson says.

While the idea that cement might not retain a temporary as well as another sounds like a nonstarter for the non-retentive cement, Dr Lawson explains that it depends on the situation. So, have both options available depending on the circumstances and the prep.

"Sometimes less retention is good as you don't want to struggle to get a temporary cement off, but other times more retention is good because you don't want your temps falling off," Dr Lawson says. "It depends on how retentive the prep is."

Some Other Considerations When Choosing Temporary Cement

In a study published in the Journal of Clinical and Experimental Dentistry, researchers found that thermocycling significantly affected the retention values of temporary cement (except for Temp-Bond^™ Clear, KaVo Kerr). Also, the researchers found that dual-cure cement showed higher retention values after thermocycling, making them suitable for cases with short or convergent tooth stumps where restoration retention could be compromised. This finding is consistent with previous research that included thermocycling.¹

Also, the researchers recommended dual-cure cement for anterior teeth when definitive restoration involves partial or complete coverage due to their translucency and retention capacity. By contrast, self-curing cement is suitable for the posterior sector and anterior sector restoration with metal-ceramic restorations where cement with eugenol can be used as adhesive cementation of the definitive prosthesis is not required.¹

Also, where the cement ends after debonding the provisional might be an essential part of a clinician's decision process; researchers found more cement remaining on the restoration when dual-cure cement was used, ironically often preferred for easy extraoral cleaning. By contrast, self-curing cement tended to stay on the teeth.¹

However, clinicians should avoid dual-cure cement when planning to use the immediate dentin sealing technique. There are indications that the resin could potentially bond with the temporary cement.¹

The main goal of temporary cementation is to provide sufficient prosthesis retention and sealing while ensuring clinicians can easily remove cement when it's time. So, when deciding which temporary cements to choose as a permanent resident of your inventory, be sure you have different options for specific cases that can adapt to the unique needs of your restorative case.

Sources:

1. Román-Rodríguez JL, Millan-Martínez D, Fons-Font A, Agustín-Panadero R, Fernández-Estevan L. Traction test of temporary dental cements. J Clin Exp Dent. 2017;9(4):e564-e568. Published 2017 Apr 1. doi:10.4317/jced.53732
2. Ghidrai, G. Dental Cement Permanent and Temporary Cementation. Infodentis.com. Accessed May 22, 2023. https://www.infodentis.com/fixed-prosthodontics/dental-cement.php
3. Lineberry, J. Selecting the Right Provisional Cement - Spear Education, Speareducation.com. Accessed May 22, 2023. https://www.speareducation.com/spear-review/2016/03/selecting-the-right-provisional-cement