This study characterized the interactions of mineral trioxide aggregate with a synthetic tissue fluid composed of a neutral phosphate buffer saline solution and root canal dentin in extracted human teeth using inductively coupled plasma-atomic emission spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction. Mineral trioxide aggregate exposed to synthetic tissue fluid at 37°C released its metallic constituents and produced precipitates with a composition and structure similar to that of hydroxyapatite [Ca 10 (PO4) 6 (OH) 2 -HA]. Endodontically prepared teeth filled with mineral trioxide aggregate and stored in synthetic tissue fluid at 37°C for 2 months produced at the dentin wall an adherent interfacial layer that resembled hydroxyapatite in composition. The authors conclude that Ca, the dominant ion released from mineral trioxide aggregate, reacts with phosphates in synthetic tissue fluid, yielding hydroxyapatite. The dentin-mineral trioxide aggregate interfacial layer results from a similar reaction. The sealing ability, biocompatibility, and dentinogenic activity of mineral trioxide aggregate is attributed to these physicochemical reactions. (MTA) is a mechanical mixture of three powder ingredients: Portland cement (75%), bismuth oxide (20%), and gypsum (5%) (1). It also contains trace amounts of SiO 2 , CaO, MgO, K 2 SO 4 and Na 2 SO 4 . The major component, Portland cement, is a mixture of dicalcium silicate, tricalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite. MTA is prepared as a mixture of powder and water and is used in a slurry form, which gradually hardens in the oral environment.Since its introduction as a root-end filling material in 1993, the use of MTA has expanded to many applications of root repair and bone healing (2-4). These applications include direct pulp capping, repair of root and furcation perforations, and apexification. A material for such applications should have the ability to seal the dental pulp from bacterial and chemical invasion, and the candidate material should be biocompatible to prevent toxicity and tissue irritability. Both in vitro and in vivo studies have shown that MTA fulfills these requirements quite satisfactorily. The superior sealing ability of MTA over conventional retrograde filling materials, such as amalgam, IRM, and Super EBA, has been demonstrated in numerous microleakage tests using dye, fluid, bacteria, and endotoxin infiltration techniques (5-10). Its excellent biocompatibility has been evidenced in several favorable biologic processes induced by MTA, namely, minimal toxicity and pulpal irritation, mild periapical inflammation, nonmutagenicity, cell adherence and growth, increased levels of alkaline phosphatase and osteocalcin, interleukin production (IL-6, IL-8), periodontal ligament attachment, cementum growth, and dentinal bridge formation (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26).Studies on MTA have mainly examined its various biologic properties, but lit...

Background/aim: The majority of traumatic dental injuries (TDI) in childhood and adolescence occur in schools. Since school teachers are often the first responders, their knowledge about the emergency management of TDI needs to be adequate. The aim of this systematic review was to assess and analyse the global status of this knowledge as reported in previous studies and to provide recommendations for future research. Methods: The protocol was designed as per PRISMA guidelines and registered in PROSPERO. A broad-based search using text-words and MeSH terms was performed in established databases as per a predefined strategy. Cohort-studies, crosssectional, case-control studies and randomized/non-randomized trials without any distinction of language and year of publication were included while those without details of sampling strategy, validity and reliability were excluded. Data extraction was performed, risk of bias assessment was done by the Joanna-Briggs-Institute's critical appraisal checklist and meta-analysis was performed for four question stems using a random effects model. Results: Twenty-three studies were included for qualitative analysis. Most of the studies had been conducted in Asia from 2009 to 2019. Ten studies used case-based questionnaires, mostly adapted from previous studies. Moderate to high risk of bias was observed in 14 studies. Less than 50% of teachers had witnessed a TDI in 8 studies and >75% desired to know more about TDI management in most studies. Less than 50% of teachers in 5 out of 6 studies knew about immediate replantation of avulsed permanent teeth, <25% knew about storage of an avulsed tooth in 16 studies and <50% knew about cleaning of a dirty avulsed tooth in 8 studies. Meta-analysis revealed I 2 values of >95% with 17% of teachers having previous dental-trauma firstaid training and 38% knowing about replantation within 30 minutes. Conclusion: The awareness level in several areas of the world is unknown. Studies lacked well-designed questionnaires and teachers exhibited low self-belief and knowledge level in the majority of studies. | 569 TEWARI ET Al. How to cite this article: Tewari N, Goel S, Rahul M, et al. Global status of knowledge for prevention and emergency management of traumatic dental injuries among school teachers: A systematic review and meta-analysis. Dent

IntroductionCongenital epulis is a rare lesion found on the alveolar process of a newborn child, diagnosed soon after birth. The lesion has a site predilection for the anterior maxillary alveolar process and a 9:1 sex predilection for females. Once diagnosed the traditional management of the lesion has been surgical excision under general anesthesia.Case presentationThe purpose of this case report is to describe spontaneous regression of congenital epulis in a three week old healthy African American female child. She presented with a 1.5 cm bilobed sessile nodular lesion in the region of the right maxillary cuspid. The clinical impression was congenital epulis. Since the lesion was not interfering with feeding and respiration, a conservative approach was taken. The child was followed-up for 18 months, during which the lesion progressively regressed.ConclusionsConservative management prevented unnecessary surgery and anesthesia exposure in a neonate.

Bioactive glass (BAG) is often used as a filler material for repair of dental bone defects. Although there is evidence of osteogenic potential of this material, it is not clear yet whether the material exhibits potential for dentinogenesis. Hence, the aim of the present study was to evaluate BAG as a pulpotomy agent and to compare it with three commercially available pulpotomy agents such as formocresol (FC), ferric sulfate (FS), and mineral trioxide aggregate (MTA). Pulpotomies were performed in 80 maxillary first molars of Sprague Dawley rats, and pulp stumps were covered with BAG, FC, FS, and MTA. Histologic analysis was performed at 2 weeks and then at 4 weeks after treatment. Experimental samples were compared with contra-lateral normal maxillary first molars. At 2 weeks, BAG showed inflammatory changes in the pulp. After 4 weeks, some samples showed normal pulp histology, with evidence of vasodilation. At 2 weeks, MTA samples showed some acute inflammatory cells around the material with evidence of macrophages in the radicular pulp. Dentine bridge formation with normal pulp histology was a consistent finding at 2 and 4 weeks with MTA. Ferric sulfate showed moderate inflammation of pulp with widespread necrosis in coronal pulp at 2 and 4 weeks. Formocresol showed zones of atrophy, inflammation, and fibrosis. Fibrosis was more extensive at 4 weeks with evidence of calcification in certain samples. Among the materials tested, MTA performed ideally as a pulpotomy agent causing dentine bridge formation while simultaneously maintaining normal pulpal histology. It appeared that BAG induced an inflammatory response at 2 weeks with resolution of inflammation at 4 weeks.