Antibacterial biofilm efficacy of calcium hydroxide loaded on Gum Arabic nanocarrier: an in-vitro study.

BACKGROUND: An innovative intracanal medication formulation was introduced in the current study to improve the calcium hydroxide (Ca(OH)2) therapeutic capability against resistant Enterococcus faecalis (E. faecalis) biofilm. This in-vitro study aimed to prepare, characterize, and evaluate the antibacterial efficiency of Ca(OH)2 loaded on Gum Arabic (GA) nanocarrier (Ca(OH)2-GA NPs) and to compare this efficiency with conventional Ca(OH)2, Ca(OH)2 nanoparticles (NPs), GA, and GA NPs. MATERIALS AND METHODS: The prepared nanoparticle formulations for the tested medications were characterized using Transmission Electron Microscope (TEM) and Fourier-Transform Infrared Spectroscopy (FTIR). 141 human mandibular premolars were selected, and their root canals were prepared. Twenty-one roots were then sectioned into 42 tooth slices. All prepared root canals (n = 120) and teeth slices (n = 42) were divided into six groups according to the intracanal medication used. E. faecalis was inoculated in the samples for 21 days to form biofilms, and then the corresponding medications were applied for 7 days. After medication application, the residual E. faecalis bacteria were assessed using CFU, Q-PCR, and SEM. Additionally, the effect of Ca(OH)2-GA NPs on E. faecalis biofilm genes (agg, ace, and efaA) was investigated using RT-PCR. Data were statistically analyzed at a 0.05 level of significance. RESULTS: The synthesis of NPs was confirmed using TEM. The results of the FTIR proved that the Ca(OH)2 was successfully encapsulated in the GA NPs. Ca(OH)2-GA NPs caused a significant reduction in the E. faecalis biofilm gene expression when compared to the control (p < 0.001). There were significant differences in the E. faecalis CFU mean count and CT mean values between the tested groups (p < 0.001) except between the Ca(OH)2 and GA CFU mean count. Ca(OH)2-GA NPs showed the least statistical E. faecalis mean count among other groups. SEM observation showed that E. faecalis biofilm was diminished in all treatment groups, especially in the Ca(OH)2-GA NPS group when compared to the control group. CONCLUSIONS: Ca(OH)2 and GA nanoparticles demonstrate superior anti-E. faecalis activity when compared to their conventional counterparts. Ca(OH)2-GA NPs showed the best antibacterial efficacy in treating E. faecalis biofilm. The tested NP formulations could be considered as promising intracanal medications.

Cryotherapy: A New Paradigm of Treatment in Endodontics.

INTRODUCTION: The aim of this review article was to discuss the concept of cryotherapy, its mechanism, physiological effect, and its different applications in the field of endodontics. METHODS: The selected articles were limited to those published in the English language using the following key words: cryotherapy, cryogenic treatment of nickel-titanium, cold therapy, and cryotherapy in endodontics. The screening of articles was based on an electronic search of the following databases: PubMed, Scopus, Web of Science, and Egyptian Knowledge Bank. RESULTS: The initial search yielded 98 citations, 78 of which were included. On the basis of the collected data, 32 studies addressed the physiological effect of cryotherapy, 10 focused on illustrating a different application of cryotherapy during root canal treatment, and 36 were concerned with the effect of cryogenic treatment on endodontic instruments. CONCLUSIONS: It can be concluded that cryotherapy is a simple and cheap supplementary method for minimizing postoperative pain in cases of symptomatic apical periodontitis and for controlling pulpal hemorrhage during vital pulp therapy. Undoubtedly, it is also an indispensable measure for controlling postsurgical swelling and pain after endodontic surgery. However, further studies are needed to clarify the effect of cryogenic treatment of the recent generations of nickel-titanium rotary instruments.

Illumina MiSeq Sequencing for Preliminary Analysis of Microbiome Causing Primary Endodontic Infections in Egypt.

The use of high throughput next generation technologies has allowed more comprehensive analysis than traditional Sanger sequencing. The specific aim of this study was to investigate the microbial diversity of primary endodontic infections using Illumina MiSeq sequencing platform in Egyptian patients. Samples were collected from 19 patients in Suez Canal University Hospital (Endodontic Department) using sterile # 15K file and paper points. DNA was extracted using Mo Bio power soil DNA isolation extraction kit followed by PCR amplification and agarose gel electrophoresis. The microbiome was characterized on the basis of the V3 and V4 hypervariable region of the 16S rRNA gene by using paired-end sequencing on Illumina MiSeq device. MOTHUR software was used in sequence filtration and analysis of sequenced data. A total of 1858 operational taxonomic units at 97% similarity were assigned to 26 phyla, 245 families, and 705 genera. Four main phyla Firmicutes, Bacteroidetes, Proteobacteria, and Synergistetes were predominant in all samples. At genus level, Prevotella, Bacillus, Porphyromonas, Streptococcus, and Bacteroides were the most abundant. Illumina MiSeq platform sequencing can be used to investigate oral microbiome composition of endodontic infections. Elucidating the ecology of endodontic infections is a necessary step in developing effective intracanal antimicrobials.

Cutting efficiency of twisted versus machined nickel-titanium endodontic files.

INTRODUCTION: The purpose of this study was to compare the efficacy of the cutting ability of two different instruments, concerning changes in the dentin thickness removed and root canal volume, by using multislice computed tomography scanning. METHODS: Thirty single-rooted mandibular premolars were divided into two equal groups according to the preparation system used: the twisted file (TF) and ProTaper (Dentsply Maillefer, Ballaigues, Swizerland). Dentin thickness along the whole length of the root canal and canal volume were measured before and after instrumentation by using multislice computed tomography scanning and image analysis software. RESULTS: ProTaper removed significantly more dentin from the mesiodistal and buccolingual directions of the root canal than the TF (P < .05). No significant difference was recorded for the changes in root canal volume between the two systems (P > .05). CONCLUSIONS: The TF system was found to cut dentin efficiently with more uniform cutting than ProTaper system.