Comparative evaluation of postoperative pain and periapical healing after root canal treatment using three different base endodontic sealers – A randomized control clinical trial

Background

The aim of the present study was to evaluate and compare the postoperative pain and periapical healing after root canal treatment using three different base endodontic sealers.

Material and Methods

Primary root canal treatment was initiated in 63 patients diagnosed with necrotic pulp and apical periodontitis, cleaning and shaping was completed in two visit and different base endodontic sealers were used for obturation were selected based on the random allocation of the participants to the following groups; Tubli-Seal, AH Plus and BioRoot RCS. Postoperative pain was recorded by using 100 mm visual analog scale at 24 h, 48 h, 72 h and 7 d after obturation. Digital periapical radiographic evaluation was done to assess rate of periapical healing at baseline, 1, 3 and 6 months. Statistical analysis was done using Kruskal Wallis test and one-way ANOVA.

Results

The mean difference in the size of periapical lesions for Tubli-Seal (6.27, 13.41), AH Plus (3.86, 9.80) and BioRoot RCS (4.05, 10.22) at 3 months and 6 months respectively. The mean pain scores at 24 h for Tubli-Seal (17.94 ± 11.35), AH Plus (11.57 ± 11.18), BioRoot RCS (4.73 ± 7.72). At 48 h, Tubli-Seal (5.26 ± 9.04), AH Plus (1.57 ± 3.74) and BioRoot RCS (1.57 ± 3.74) respectively. The mean pain score at 72 h for Tubli-Seal was 2.63 ± 7.33 whereas none of the patients had reported pain in AH Plus and BioRoot RCS group. None of the patients had pain after 7 d of treatment.

Conclusions

BioRoot RCS showed less postoperative pain compared to AH Plus and Tubli-Seal and showed better periapical healing compared to AH Plus and Tubli-Seal at 3 and 6 months intervals respectively.

Key words:BioRoot RCS, root canal obturation, root canal sealers, periapical periodontitis, Periapical healing, postoperative pain.

Use of powered air-purifying respirators during surgical interventions

This clinical study confirms user acceptability of PAPR during surgery both at operating room team level as well as by groups of surgeons, anaesthesiologists and nursing level. While some care is needed in the use of this equipment, surgery can be performed safely with satisfactory user experience.

Therefore PAPR is useable for surgery but scope exists for improvement.

Transgenic bovine chimeric offspring produced from somatic cell-derived stem-like cells

We have developed a method, using nuclear transplantation, to produce transgenic embryonic stem (ES)-like cells from fetal bovine fibroblasts. These cells, when reintroduced into preimplantation embryos, differentiated into derivatives from the three embryonic germ layers, ectoderm, mesoderm, and endoderm, in 5-month-old animals. Six out of seven (86%) calves born were found to be chimeric for at least one tissue. These experiments demonstrate that somatic cells can be genetically modified and then de-differentiated by nuclear transfer into ES-like cells, opening the possibility of using them in differentiation studies and human cell therapy.

Cloned transgenic calves produced from nonquiescent fetal fibroblasts

An efficient system for genetic modification and large-scale cloning of cattle is of importance for agriculture, biotechnology, and human medicine. Here, actively dividing fetal fibroblasts were genetically modified with a marker gene, a clonal line was selected, and the cells were fused to enucleated mature oocytes. Out of 28 embryos transferred to 11 recipient cows, three healthy, identical, transgenic calves were generated. Furthermore, the life-span of near senescent fibroblasts could be extended by nuclear transfer, as indicated by population doublings in fibroblast lines derived from a 40-day-old fetal clone. With the ability to extend the life-span of these primary cultured cells, this system would be useful for inducing complex genetic modifications in cattle.

Cloning: new breakthroughs leading to commercial opportunities

Research on cloning animals, again, came to the forefront of public attention in 1997. Most scientists involved in biomedical and agricultural research have emphasized the benefits, of which there are many, of cloning to the public. Basic studies on nuclear transfer have and will continue to contribute to our understanding of how genomic activation and cell cycle synchrony affect nuclear reprogramming and cloning efficiencies, specifically. Also, more basic information on actual mechanisms and specific factors in the oocyte causing nuclear reprogramming is forthcoming. As new molecular approaches in functional genomics are combined with nuclear transfer experiments, new genes involved in nuclear reprogramming will be found. The commercial potentials of products stemming from discoveries in cloning are vast. Cloning will be a more efficient, faster and more useful way of making transgenic fetuses for cell therapies, adult animals for protein production and organs for xenotransplantation. Clearly there are new opportunities in animal cloning technology that will produce many benefits to society.

Tissue-specific expression, developmental regulation, and genetic mapping of the gene encoding CCAAT/enhancer binding protein

This paper presents the results of experiments that determine the chromosomal location of the mouse gene encoding CCAAT/enhancer binding protein (C/EBP) and measure its expression as a function of tissue type and temporal period of development in mice and rats. Three alleles of the C/EBP gene were identified according to restriction fragment length polymorphisms. The strain distribution pattern of the three alleles was determined in recombinant inbred mouse strains and compared to that of other mouse genes. These results mapped the gene to a position within 2.5 centimorgans (cM) of the structural gene encoding glucose phosphate isomerase on chromosome 7 of the mouse. The expression pattern of the C/EBP gene was studied by a combination of nucleic acid hybridization and antibody staining assays. High levels of C/EBP mRNA were observed in tissues known to metabolize lipid and cholesterol-related compounds at uncommonly high rates. These included liver, fat, intestine, lung, adrenal gland, and placenta. More detailed analysis of two of these tissues, liver and fat, showed that C/EBP expression was limited to fully differentiated cells. Moreover, analysis of the temporal pattern of expression of C/EBP mRNA in two tissues, liver and intestine, revealed a coordinated induction just prior to birth. These observations raise the possibility that the synthesis of C/EBP may be responsive to humoral factors and that modulation in C/EBP expression might mediate coordinated changes in gene expression that facilitate adaptive challenges met during development or during the fluctuating physiological states of adult life.