The Thera Family - a new line of groundbreaking materials
Dr. Mark Cannon is a renowned clinical researcher, lecturer, and key opinion leader in pediatric dentistry. In a career that spans 40 years, he has witnessed the evolution of biomaterials and has actively tried to improve them.
His years of material research and development have culminated in a new line of groundbreaking materials—the Thera products from BISCO.
“All of us have an obligation to look at what we’re doing in our practices and ask, ‘What is it that we can do much better? What is that we can help develop? That’s why I’ve been so involved in a number of dental companies, trying to improve the quality of care by improving the materials we use everyday,” said Dr. Cannon.
Like many new ideas, Dr. Cannon’s started with a problem he wanted to solve. For deep restorations, he would follow the open-sandwich technique and would apply a base of resin-modified glass ionomer. This biointeractive product releases fluoride, which helps with fluorapatite. However, he found that fluorapatite is not that important to the dentin, nor is it that important to the pulp. Fluoride as an enzyme inhibitor cuts back on growth of bacteria, but it does not create an alkaline environment to help heal the dentin. RMGIs are acidic and work by acid-based reaction, so it takes time for the pH to neutralize.
Dr. Cannon’s idea for a better lining was a resin-modified Portland cement, a component in mineral trioxide aggregate (MTA) that consists of tricalcium silicate, dicalcium silicate, and tricalcium aluminate.
This new material would work ideally—promote the formation of new hard tissue and prevent the growth of cavity-producing bacteria. Eventually, his idea led to the creation of BISCO’s Thera family of calcium-releasing products. But before he approached the company, Dr. Cannon wanted to test his hypothesis. He attempted to formulate his own resin-based tricalcium/dicalcium material, which he humorously recalls went “very badly.”
“It had no calcium release whatsoever because the resin was wrong. This is where you need the great chemistry that BISCO is known for,” Dr. Cannon said. “You have to have chemists who understand how to use the different monomers, so you can have good polymerization.”
Dr. Cannon notes that other companies have tried to make a light-cured mineral trioxide aggregate (MTA) product, but without success.
“They haven’t worked because they were not able to get the right type of monomer mix that will allow the product to be hydrophilic enough for the release of the calcium and alkalinity to work.” According to Dr. Cannon, research has confirmed that BISCO’s TheraCal LC accomplishes what these other materials couldn’t.
Let’s take a closer look at the three products in the Thera family:
TheraCal LC is a light-cured, resin-modified calcium silicate and the first Thera product created by BISCO. It’s intended for use as a pulp-capping and lining material as an alternative to calcium hydroxide. It helps to protect the pulp as a thermal insulator1-2 and acts as a protective seal of the pulp.1-4
TheraCal LC gives dentists the ability to instantly light-cure the material and restore on top of it, and its calcium-releasing ability* creates an alkaline pH to promote healing and apatite formation.5-6 The benefits of calcium release and ease-of-use created a buzz around this product, which has undergone numerous evaluations since its launch in 2011.
Read the TheraCal LC evaluation by independent Dental Product Shopper evaluators.
Introduced in 2017, TheraCem is a self-adhesive resin cement that bonds well to all substrates, including composite, metal, and zirconia, and is indicated for metal and resin crowns/bridges/inlays/onlays, porcelain and ceramic crowns/inlays/onlays, metal and fiber endodontic posts, and implant-supported restorations.
TheraCem continuously releases calcium and fluoride,7 transitioning from acidic to alkaline pH in minutes.8 The Thera technology allows for calcium ions to pass between the material and the tooth.
Watch the video evaluation of TheraCem below.
TheraCal PT is a dual-cured, resin-modified calcium silicate. It has the same Thera technology as its predecessors, but is indicated for pulpotomies. Its hydrophilic matrix facilitates calcium release, and the dual-barrelled syringe allows for immediate mixing and placement of the material, so dentists can quickly place, cure, and restore on top of deep cavity preparations and pulpotomies. After 7 days, the pH level becomes alkaline at 11.5.*
“I personally love [TheraCal PT] for deep basing. I use it whenever I get close to the pulp. Being dual-cured, it continues to cure, so you don’t have to worry about any uncured monomer,” said Dr. Cannon.
Read the full TheraCal PT evaluation.
Where does Dr. Cannon think the future of biomaterials is heading and what questions is he asked most often?
Watch the full video interview to learn more.
*Data on file
Sources
1. Sangwan P; Sangwan A; Duhan J; Rohilla A. Tertiary dentinogenesis with calcium hydroxide: a review of proposed mechanisms. Int Endod J. 2013; 46(1):3-19
2. Selcuk SAVAS, Murat S. BOTSALI, Ebru KUCUKYILMAZ, Tugrul SARI. Evaluation of temperature changes in the pulp chamber during polymerization of light-cured pulp-capping materials by using a VALO LED light curing unit at different curing distances. Dent Mater J. 2014;33(6):764-9.
3. Cantekin K. Bond strength of different restorative materials to light-curable mineral trioxide aggregate. J Clin Pediatr Dent. 2015 Winter;39(2):143-8.
4. Mechanical Properties of New Dental Pulp-Capping Materials Over Time. M. NIELSEN, R. VANDERWEELE, J. CASEY, and K. VANDEWALLE, USAF, JBSA-Lackland, TX, , J Dent Res 93(Spec Iss A): 495, 2014 (www.dentalresearch.org)
5. ADA definitions for direct and indirect pulp capping at: www.ada.org/en/publications/cdt/glossary-of-dental-clinical-and-administrative-ter
6. Okabe T, Sakamoto M, Takeuchi H, Matsushima K (2006) Effects of pH on mineralization ability of human dental pulp cells. Journal of Endodontics 32, 198-201.
7. Gleave CM, Chen L, Suh BI. Calcium & fluoride recharge of resin cements. Dent Mater. 2016 (32S):e26.
8. New Self-adhesive Resin Cement With Alkaline pH. Chen L, Gleave C, Suh B, J Dent Res96(A):#286, 2017.