Research on DAP and TAP in Endodontic Regeneration

According to recent research, it has been found that the use of 1 mg/mL DAP resulted in significantly higher push-out bond strength compared with the typical clinical concentration of TAP and DAP regardless of the type of the root cement used.

The study is published in the European Journal of Dentistry.

The most contemporary treatment option to manage immature teeth with pulpal necrosis is endodontic regeneration (ER), which depends on the efficient disinfection of the root canal. Numerous intracanal medicaments have been proposed for ER treatment, such as:

• Ca(OH)₂
• Triple antibiotic paste (TAP) (equal amounts of metronidazole, ciprofloxacin, and minocycline)
• Double antibiotic paste (DAP) (equal parts of metronidazole and ciprofloxacin)

Furthermore, lower concentrations of DAP and TAP ranging from 1 to 5 mg/mL have been recommended by the American Association of Endodontists (AAE) to minimize the harmful biological effects of these medicaments on stem cells from apical papillae.

Therefore, Rayan B. Yaghmoor and colleagues from the Department of Restorative Dentistry, College of Dental Medicine, Umm Al-Qura University, Makkah, Saudi Arabia aimed to evaluate the effects of typical clinical concentration (1,000 mg/mL), low concentration (1 mg/mL) triple antibiotic pastes (TAP), and double antibiotic pastes (DAP) on the bond strength between various root cement and radicular dentin.

The authors studied a total sample of 144 intact single-rooted human teeth. Each tooth was horizontally decoronated and canals instrumented. The roots were treated for 4 weeks with:

• Ca(OH)₂
• 1,000 mg/mL of TAP or DAP
• 1 mg/mL of TAP or DAP

Untreated roots served as a control. After treatment, the medicaments were irrigated and each group was divided into three subgroups receiving MTA, Biodentine, or Endosequence putty cement. After 2 weeks, coronal and middle root cylinders were obtained from each root. Push-out bond strength test and failure analysis were performed for all root cylinders.

The results showed that 1 mg/mL DAP and TAP and Ca(OH)₂ demonstrated significantly higher bond strength compared with the typical clinical concentration and the control groups. For Biodentine applied coronally in the roots, 1 mg/mL of DAP resulted in significantly higher bond strength than all other groups. For Endosequence putty cement applied coronally in the roots, 1 mg/mL of DAP offered significantly higher bond strength than all groups except for Ca(OH)₂.

Hence, they concluded that "1 mg/mL of DAP loaded into a hydrogel methylcellulose system and Ca(OH)₂ did not have a significant negative effect on the bond strength of calcium silicate-based cement to radicular dentin."