[2]: 491–494 As of 2021[update], recent improvements in dressing materials have significantly increased the success rates of pulp capping teeth with cavities.
The tooth is then washed and dried, and the protective material placed, followed finally by a dental restoration which gives a bacteria-tight seal to prevent infection.
"[4][8] The difficulty with this technique is estimating how rapid the carious process has been, how much tertiary dentin has been formed and knowing exactly when to stop excavating to avoid pulp exposure.
However, calcium hydroxide and mineral trioxide aggregate (MTA) are the preferred material of choice in clinical practice due to their favourable outcome.
Studies have demonstrated unfavourable results for ZOE when compared to calcium hydroxide as a direct pulp-capping material as it causes pulpal necrosis.
This is due to their superior properties of good biocompatibility and adhesive nature, providing coronal seal to prevent bacteria infiltration.
Studies have demonstrated that it encourages bleeding due to its vasodilating properties hence impairing polymerisation of the material, affecting its ability to provide a coronal seal when used as a pulp capping agent.
In addition, the material triggers chronic inflammation even without the presence of bacteria, making it an unfavourable condition for pulp healing to take place.
[10] Calcium hydroxide (CaOH) is an organo-metallic cement that was introduced into dentistry in the early twentieth century[11] and there have since been many advantages to this material described in much of the available literature.
[12][13] In one experiment conducted by Stuart et al. (1991), bacteria-inoculated root canals of extracted human teeth were treated with CaOH for one hour against a control group with no treatment and the results yielded 64–100% reductions in all viable bacteria.
[14] This alkaline environment created around the cement has been suggested to give beneficial irritancy to pulpal tissues and stimulates dentin regeneration.
[20] Mineral trioxide aggregate (MTA) is a recent development of the 1990s[21] initially as a root canal sealer but has seen increased interest in its use as a direct pulp-capping material.
Studies that compare pulp capping abilities of MTA to CaOH in human teeth yielded generally equal and similarly successful healing outcomes at a histological level from both materials.
One study of indirect pulp capping recorded success rates of 98.3% and 95% using bioactive tricalcium silicate [Ca3SiO5]-based dentin substitute and light-activated calcium hydroxide [CA(OH)2]-based liner respectively.
[32] A further study testing medical Portland cement, mineral trioxide aggregate (MTA) and calcium hydroxide in indirect pulp treatment found varying success rates of 73–93%.