Ex Vivo Effect of Novel Lipophosphonoxins on Root Canal Biofilm Produced by Enterococcus faecalis: Pilot Study

Lipophosphonoxins-A Novel Group of Broad Spectrum Antibacterial Compounds

Lipophosphonoxins (LPPOs) represent a new group of membrane-targeting antibiotics. Three generations of LPPOs have been described: First-generation LPPOs, second-generation LPPOs, and LEGO-LPPOs. All three generations have a similar mode of bactericidal action of targeting and disrupting the bacterial cytoplasmic membrane of prokaryotic cells, with limited effect on eukaryotic cells. First-generation LPPOs showed excellent bactericidal activity against Gram-positive species, including multiresistant strains. Second-generation LPPOs broaden the antibiotic effect also against Gram-negative bacteria. However, both first- and second-generation LPPOs lose their antibacterial activity in the presence of serum albumin. LEGO-LPPOs were found to be active against both Gram-positive and Gram-negative bacteria, have better selectivity as compared to first- and second-generation resistance to LEGO-LPPOs was also not observed, and are active even in the presence of serum albumin. Second-generation LPPOs have been studied as antimicrobial additives in bone cement and as nanofiber dressing components in the treatment of wound infections in mice. Second-generation LPPOs and LEGO-LPPOs were also tested to treat ex vivo simulated endodontic infections in dental root canals. The results of all these studies were encouraging and suggested further investigation of LPPOs in these indications. This paper aims to review and compile published data on LPPOs.

Bromelain-based endodontic irrigant: preparation, properties, and biocompatibility: An in-vitro study

The aim of the study was to determine the properties, efficacy and biocompatibility of combining bromelain enzyme, chlorohexidine and EDTA (BCE) to create a novel endodontic irrigant. Fourier transform infrared spectrometry was performed to confirm the stability of the BCE and direct contact inhibition test was performed to determine antibacterial action. Baseline pH and surface tension of irrigants was compared with determine stability. Subcutaneous injection to dorsal skin of rabbits was graded for presence of inflammation, oedema, granulation and fibrosis. BCE caused less overall irritation, less oedematous and was earlier to heal than 2.5% NaOCl. The pH stability of BCE was also superior to 2.5% NaOCl. A one-way ANOVA test was performed for the direct contact inhibition and microleakage test. A significant difference was determined (p ≤ 0.05) between BCE and 2.5% NaOCl for antibacterial action. BCE irrigant is effective in preparing dentinal surfaces for root canal without adverse effects and promising longevity.

Essential oils as adjuvants in endodontic therapy: myth or reality?

To enhance endodontics, the search for new antibacterials that can improve infected tooth root canal treatment is ongoing. As potent antibacterial and antibiofilm agents, essential oils (EOs) have been suggested as novel endodontic materials. Several studies indicate that EO-based irrigants and medicaments show promising reductive potential against the most important intracanal pathogen, Enterococcus faecalis, and notably contribute to intracanal biofilm eradication. In terms of additional benefits that EO-based endodontic materials can provide, their antioxidant and anti-inflammatory potential are also important, but they have only scarcely been explored in research. Investigations into the benefits of EO-based endodontic materials together with their biocompatibility are needed. The results presented in this review strongly encourage further research on this topic.