Identification of root canal microbiota profiles of periapical tissue diseases using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Objectives: The purpose of this study was to identify microorganisms isolated from various periapical tissue diseases using Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) and classify them via an unsupervised machine learning approach.

Methods: A total of 150 patients with various apical conditions and teeth in need of endodontic retreatment were divided into five groups, including Retreatment, Acute Apical Abscess, Chronic Apical Abscess, Acute Apical Periodontitis, and Chronic Apical Periodontitis. Samples were collected from root canals using paper points after agitating with a #10 K file then microorganisms were identified using MALDI-TOF-MS.

Contemporary research trends on nanoparticles in endodontics: a bibliometric and scientometric analysis of the top 100 most-cited articles.

Objectives: Advancements in nanotechnology have led to the widespread usage of nanoparticles in the endodontic field. This bibliometric study aimed to determine and analyze the top 100 most-cited articles about nanoparticles in endodontics from 2000 to 2022.

Materials And Methods: A detailed electronic search was conducted on the "Clarivate Analytics Web of Science, All Databases" to receive the most-cited articles related to the topic.

A G protein-coupled, IP3/protein kinase C pathway controlling the synthesis of phosphaturic hormone FGF23.

Dysregulated actions of bone-derived phosphaturic hormone fibroblast growth factor 23 (FGF23) result in several inherited diseases, such as X-linked hypophosphatemia (XLH), and contribute substantially to the mortality in kidney failure. Mechanisms governing FGF23 production are poorly defined. We herein found that ablation of the Gq/11α-like, extralarge Gα subunit (XLαs), a product of GNAS, exhibits FGF23 deficiency and hyperphosphatemia in early postnatal mice (XLKO).

Comparison of Four Electronic Apex Locators in Detecting Working Length: An Ex Vivo Study.

Aim: To compare the accuracy of four different electronic apex locators (EALs) in detecting a position 0.5 mm short of the major foramen.

Materials And Methods: The actual working length of thirty-five extracted human teeth was determined visually as 0.

Ablation of the Stimulatory G Protein α-Subunit in Renal Proximal Tubules Leads to Parathyroid Hormone-Resistance With Increased Renal Cyp24a1 mRNA Abundance and Reduced Serum 1,25-Dihydroxyvitamin D.

PTH regulates serum calcium, phosphate, and 1,25-dihydroxyvitamin D (1,25(OH)2D) levels by acting on bone and kidney. In renal proximal tubules (PTs), PTH inhibits reabsorption of phosphate and stimulates the synthesis of 1,25(OH)2D. The PTH receptor couples to multiple G proteins.

The evaluation of two rotary instrumentation techniques under "operator-related variables" standardized conditions.

Objective: We aimed here to evaluate the enlargement characteristics of two nickel-titanium rotary instrument systems that use two different preparation techniques, in simulated root canals under "operator-related variables" standardized conditions.

Materials And Methods: A total of 40 simulated canals in resin blocks were divided into two groups as the Mtwo group for use with a single-length technique and the ProTaper instrument system group for use with crown down technique. To standardize the operator-related variables, all preparations were carried out with a computer controlled device that was developed and used previously as described in a published study.

Postnatal establishment of allelic Gαs silencing as a plausible explanation for delayed onset of parathyroid hormone resistance owing to heterozygous Gαs disruption.

Pseudohypoparathyroidism type-Ia (PHP-Ia), characterized by renal proximal tubular resistance to parathyroid hormone (PTH), results from maternal mutations of GNAS that lead to loss of α-subunit of the stimulatory G protein (Gαs) activity. Gαs expression is paternally silenced in the renal proximal tubule, and this genomic event is critical for the development of PTH resistance, as patients display impaired hormone action only if the mutation is inherited maternally. The primary clinical finding of PHP-Ia is hypocalcemia, which can lead to various neuromuscular defects including seizures.

A case of a benign cementoblastoma treated by enucleation and apicoectomy.

Cementoblastoma is a rare, benign, odontogenic neoplasm of ectomesenchymal origin, representing less than 6% of all odontogenic tumors. Despite its well-known typical features, there are still controversies regarding the management of the condition. This article presents the case of a benign cementoblastoma in a 17-year-old girl.

Solubility and apical sealing characteristics of a new calcium silicate-based root canal sealer in comparison to calcium hydroxide-, methacrylate resin- and epoxy resin-based sealers.

Aim: To assess and compare the water sorption, solubility and apical sealing ability of iRoot SP and three other widely used root canal sealers.

Materials And Methods: Solubility was assessed by immersing standardized samples of calcium silicate- (iRoot SP), calcium hydroxide- (Sealapex), methacrylate resin- (EndoREZ) and epoxy resin- (AH Plus) based sealers in distilled water and measuring weight gain and weight loss at 6 h, 24 h and daily for 14 days. Roots of extracted mandibular premolars (n = 80) were prepared with 0.

Comparison of cyclic fatigue resistance of three different rotary nickel-titanium instruments designed for retreatment.

Introduction: A number of rotary nickel-titanium (NiTi) systems have been developed to provide better, faster, and easier cleaning and shaping of the root canal system, and recently, rotary NiTi systems designed for root canal retreatment have been introduced. Because the main problem with the rotary NiTi files is fracture, the aim of this study was to compare the cyclic fatigue resistance of 3 different rotary NiTi systems designed for root canal retreatment.

Methods: Total of 60 instruments of 3 different rotary NiTi systems designed for root canal retreatment were used in this study.

Cyclic fatigue resistance of new and used Mtwo rotary nickel-titanium instruments in two different radii of curvature.

The fracture of nickel-titanium rotary instruments is a serious problem that can jeopardise the outcome of root canal treatment. The aim of this study was to compare the cyclic fatigue resistance of new and used Mtwo rotary nickel-titanium instruments in artificial canals with two different radii of curvature. Four hundred and twenty Mtwo instruments were used in the present study.

Functional characterization of GNAS mutations found in patients with pseudohypoparathyroidism type Ic defines a new subgroup of pseudohypoparathyroidism affecting selectively Gsα-receptor interaction.

Pseudohypoparathyroidism type Ia (PHPIa) is caused by GNAS mutations leading to deficiency of the α-subunit of stimulatory G proteins (Gsα) that mediate signal transduction of G protein-coupled receptors via cAMP. PHP type Ic (PHPIc) and PHPIa share clinical features of Albright hereditary osteodystrophy (AHO); however, in vitro activity of solubilized Gsα protein is normal in PHPIc but reduced in PHPIa. We screened 32 patients classified as PHPIc for GNAS mutations and identified three mutations (p.

Transgenic overexpression of the extra-large Gsα variant XLαs enhances Gsα-mediated responses in the mouse renal proximal tubule in vivo.

XLαs, a variant of the stimulatory G protein α-subunit (Gsα), can mediate receptor-activated cAMP generation and, thus, mimic the actions of Gsα in transfected cells. However, it remains unknown whether XLαs can act in a similar manner in vivo. We have now generated mice with ectopic transgenic expression of rat XLαs in the renal proximal tubule (rptXLαs mice), where Gsα mediates most actions of PTH.

Dislocation resistance of iRoot SP, a calcium silicate-based sealer, from radicular dentine.

Introduction: The aim of this study was to evaluate the push-out bond strength of iRoot SP (Innovative Bioceramix, Vancouver, Canada) and compare it with that of other widely used root canal sealers.

Methods: Sixty extracted human maxillary canines were sectioned transversally below the cement-enamel junction to obtain 120 4-mm-thick dentin disks that were randomly divided into four groups (n = 30) for treatment with one of four different root-canal sealers (iRoot SP, AH Plus [Dentsply DeTrey GmbH, Konstanz, Germany], Sealapex [SybronEndo Corporation, Orange, CA], EndoREZ [Ultradent Inc, South Jordan, UT]). Standardized cavities were prepared to simulate root canals, cavities were filled with sealer material, and push-out bond-strength testing was performed using a universal testing machine.

Potent constitutive cyclic AMP-generating activity of XLαs implicates this imprinted GNAS product in the pathogenesis of McCune-Albright syndrome and fibrous dysplasia of bone.

Patients with McCune-Albright syndrome (MAS), characterized primarily by hyperpigmented skin lesions, precocious puberty, and fibrous dyslasia of bone, carry postzygotic heterozygous mutations of GNAS causing constitutive cAMP signaling. GNAS encodes the α-subunit of the stimulatory G protein (Gsα), as well as a large variant (XLαs) derived from the paternal allele. The mutations causing MAS affect both GNAS products, but whether XLαs, like Gsα, can be involved in the pathogenesis remains unknown.

Is endodontic treatment necessary during coronectomy procedure?

Purpose: Close proximity of the inferior alveolar nerve (IAN) to the third molar roots can result in nerve injuries during extraction of third molars. Consequently, it is necessary to determine the relationship of the nerve and roots to avoid damage to the IAN. Computed tomography scans are widely used to determine the correct relationship between the IAN and lower third molars.

Comparison of cyclic fatigue resistance of used and new RaCe instruments.

Objective: The aim of this study was to evaluate cyclic fatigue resistance of used and new RaCe rotary nickel-titanium instruments.

Study Design: Forty RaCe (FKG Dentaire, La-Chaux-de-Fonds, Switzerland) instruments of sizes 30/.06, 30/.

Identification of a novel dentin matrix protein-1 (DMP-1) mutation and dental anomalies in a kindred with autosomal recessive hypophosphatemia.

An autosomal recessive form of hypophosphatemia (ARHP) was recently shown to be caused by homozygous mutations in DMP1, the gene encoding dentin matrix protein-1 (DMP-1), a non-collagenous bone matrix protein with an important role in the development and mineralization of bone and teeth. Here, we describe a previously not reported consanguineous ARHP kindred in which the three affected individuals carry a novel homozygous DMP-1 mutation. The index case presented at the age of 3 years with bowing of his legs and showed hypophosphatemia due to insufficient renal phosphate retention.

Extralarge XL(alpha)s (XXL(alpha)s), a variant of stimulatory G protein alpha-subunit (Gs(alpha)), is a distinct, membrane-anchored GNAS product that can mimic Gs(alpha).

GNAS gives rise to multiple imprinted gene products, including the alpha-subunit of the stimulatory G protein (Gs(alpha)) and its variant XL(alpha)s. Based on genomic sequence, the translation of XL(alpha)s begins from the middle of a long open reading frame, suggesting the existence of an N-terminally extended variant termed extralarge XLalphas (XXL(alpha)s). Although XXL(alpha), like Gs(alpha) and XL(alpha)s, would be affected by most disease-causing GNAS mutations, its authenticity and biological significance remained unknown.

In vitro evaluation of matched-taper single-cone obturation with a fluid filtration method.

Objective: Widespread use of rotary nickel-titanium systems has caused manufacturers to produce gutta-percha cones that match the taper of the canals prepared with these systems. Obturations with these cones may provide 3-dimensional obturation of the root canal in less time. The aim of this study was to use a fluid filtration method to compare the apical sealing ability of matched-taper single-cone, Thermafil and lateral condensation obturations.

Re-eruption of an intruded immature permanent incisor with necrotic pulp: a case report.

Intrusive luxation is a serious dental injury that causes damage to the pulp and supporting structures of a tooth because of its dislocation into the alveolar process. This paper presents the case of the re-eruption of a severely intruded immature permanent incisor with a crown-root fracture. A 9-year-old boy was referred to the clinic 1 day after a fall.

Structural effects of sodium hypochlorite solution on RaCe rotary nickel-titanium instruments: an atomic force microscopy study.

Objective: The aim of this study was to investigate the effect of sodium hypochlorite immersion on the surface characteristics of RaCe rotary nickel-titanium instruments using atomic force microscopy (AFM).

Study Design: Four new RaCe instruments were used in this study (two 30.06 and two 30.

Comparison of shaping ability of RaCe and Hero Shaper instruments in simulated curved canals.

Objective: This study compared the shaping ability of Hero Shaper and RaCe instruments in simulated curved canals.

Study Design: Forty simulated canals in resin blocks were divided into 2 experimental groups, each comprising 20 resin blocks, and prepared with Hero Shaper and RaCe using the crown-down technique. Preoperative and postoperative photographs, recorded using a digital camera, were superimposed and aberrations were recorded.

Evaluation of the surface characteristics of used and new ProTaper Instruments: an atomic force microscopy study.

The purpose of this study was to evaluate the topography of new and used ProTaper rotary nickel-titanium (NiTi) instruments by using atomic force microscope. Four new and four used size S1, S2, F1, and F2 instruments were selected for this study. New and used instruments were analyzed on 11 points along a 3-mm section at the tip of the instrument.

Cyclic fatigue of ProTaper rotary nickel-titanium instruments in artificial canals with 2 different radii of curvature.

Objective: This study compared the cyclic fatigue resistance of ProTaper rotary nickel-titanium (NiTi) files in artificial canals with 2 different radii of curvature.

Study Design: One hundred ProTaper rotary instruments were used in this study. Twenty files of each size (S1, S2, F1, F2, and F3) were tested.