Background The management of noncavitated caries lesions before sealant therapy is a clinical challenge when the tooth needs sealant application. Sealing noncavitated carious lesions in pits and fissures may lead to failure of the fissure sealant (FS) due to incomplete sealing. Therefore the use of remineralizing agents such as nanoparticles has been suggested. This study investigated the ability of hydroxyapatite nanoparticles (nano-HA) to remineralize enamel, and their effect on sealant microleakage and shear bond strength (SBS). Methods A total of 192 third molars were demineralized and pretreated with two concentrations of nano-HA with and without sodium hexametaphosphate (SHMP), followed by phosphoric acid etching and resin FS application. The study groups were 1) etching + FS, 2) etching + nano-HA 0.15% + FS, 3) etching + nano-HA 0.03% + FS, 4) etching + mixture of nano-HA 0.15% and SHMP 0.05% + FS, 5) etching + mixture of nano-HA 0.03% + SHMP 0.01% + FS. The laboratory tests included microleakage in 50 teeth, scanning electron microscopy (SEM) evaluation in 10 samples, and SBS in 100 samples. Enamel remineralization changes were evaluated in 32 teeth with energy-dispersive X-ray spectroscopy (EDS) and field emission scanning electron microscope (FESEM). Results Nano-HA enhanced the SBS to remineralized enamel in a large percentage of nanoparticles. Mean SBS in group 2 was significantly greater than in groups 1, 3 and 4 (all P < 0.05). SBS was related to nano-HA concentration: nano-HA 0.15% yielded greater SBS (16.8 ± 2.7) than the 0.03% concentration (14.2 ± 2.1). However, its effect on microleakage was not significant. Nano-HA with or without SHMP led to enhanced enamel remineralization; however, the Calcium (Ca)/Phosphate (P) weight percent values did not differ significantly between the groups ( P > 0.05). SEM images showed that SHMP did not affect sealant penetration into the deeper parts of fissures. FESEM images showed that adding SHMP led to increased nanoparticle dispersal on the tooth surface and less cluster formation. Conclusions The ultraconservative approach (combining nano-HA 0.15% and SHMP) and FS may be considered a minimal intervention in dentistry to seal demineralized enamel pits and fissures.

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Background:Tracheal intubation can be associated with considerable hemodynamic changes, particularly in patients with uncontrolled hypertension. The GlideScope® video-laryngoscope (GVL) is a novel video laryngoscope that does not need direct exposure of the vocal cords, and it can also produce lower hemodynamic changes due to lower degrees of trauma and stimuli to the oropharynx than a Macintosh direct laryngoscope (MDL).Objectives:The aim of this clinical trial was to compare hemodynamic alterations following tracheal intubation with a GVL and MDL in patients with uncontrolled hypertension.Patients and Methods:Sixty patients who had uncontrolled hypertension and scheduled for elective surgery requiring tracheal intubation, were randomly assigned to receive intubated with either a GVL (n = 30) or a MDL (n = 30). Intubation time, heart rate, rate pressure product (RPP), and mean arterial blood pressure (MAP), were compared between the two groups at; baseline, following induction of anesthesia, after intubation, and at one minute intervals for 5 minutes.Results:A total of 59 patients finished the study. Intubation time was longer in the GVL group (9.80 ± 1.27 s) than in the MDL group (8.20 ± 1.17 s) (P < 0.05). MAP, pulse rate, and RPP were lower in the GVL than the MDL group after endotracheal intubation (P < 0.05). MAP, heart rate, and RPP returned to pre-intubation values at 3 and 4 minutes after intubation in the GVL and MDL groups, respectively (P < 0.05).Conclusions:Hemodynamic fluctuations in patients with uncontrolled hypertension after endotracheal intubation were lower with the GVL than the MDL technique.

Purpose To evaluate the influence of alloy/zirconia primer and 10‐methacryloyloxydecyl dihydrogen phosphate (MDP)‐containing resin layer treatments on the shear bond strength (SBS) of composite resin to zirconia after aging. Materials and Methods Sixty zirconia (Y‐TZP) blocks were air‐abraded (35‐µm Al2O3) and divided into 6 experimental groups (n = 10) in terms of primer/resin layer as follows: (1) control, without any primer or resin; (2) AP, Alloy Primer; (3) ZPP, Z‐Prime Plus; (4) PL/ZPP, Z‐Prime Plus with light polymerization; (5) AP+SEB, Alloy Primer along with light‐cured bonding resin of a self‐etch adhesive system (SE Bond); and (6) ZPP+SEB, Z‐Prime Plus with SE Bond. After composite resin placement and light polymerization, the specimens were stored in distilled water (37°C for 4 months) and thermal‐cycled for 6000 cycles. The SBS was tested with a universal testing machine. Statistical analysis of the SBS data was performed with one‐way ANOVA, followed by HSD Tukey test (α = 0.05). Results There were significant differences between the groups (p < 0.001, F = 116.5). All the groups revealed significantly higher SBS than the control (p < 0.001). ZPP+SEB group exhibited the highest SBS (16.14 ± 2.52 MPa) and AP group the lowest SBS (7.00 ± 1.97 MPa) among experimental groups; both had significant differences with the other groups (p < 0.001). There were no significant differences between ZPP, PL/ZPP, and AP+SEB groups (p > 0.05). Conclusions The bond strength between zirconia ceramic and composite resin was affected by different primers/resin layer. Applying an MDP‐containing resin layer along with both primers resulted in significant enhancement of SBS. This improvement for Z‐Prime Plus was significantly higher than that of Alloy Primer.

The decision to save or extract a natural tooth which has been compromised is one of the dilemmas of dental practitioners, as well as the patients. Although there was a considerable effort to save the natural teeth in the past, with the introduction of osseointegrated implants, there is a tendency to extract the compromised teeth and replace them with implant-supported prosthesis. In this article, this important clinical decision is investigated, and a successful restoration of a traumatized anterior tooth is presented.

Introduction:Mucopolysaccharidoses (MPSs) are a group of heredity storage diseases, transmitted in an autosomal recessive manner, associated with the accumulation of glycosaminoglycans (GAGs) in various tissues and organs. The concerned patients have multiple concomitant hereditary anomalies. Considering the craniofacial abnormality in these patients, airway management may be difficult for anesthesiologists. In these patients, preanesthetic assessment is necessary and performed with the accurate assessment of airways, consisting of the physical exam and radiography, MRI or CT of head and neck. An anesthesiologist should set up a “difficult intubation set” with a flexible fiber-optic bronchoscope and also, it may be necessary to discuss with an ear-nose and throat (ENT) specialist if required, for unpredicted emergency situations.Case Presentation:In this case-report we presented a 2-year-old boy with known MPSs with psychomotor retardation, bilateral corneal opacities, impaired hearing and vision, inguinal hernia, severe mitral regurgitation, micrognathia, coarse facial feature, stiff and short neck and restricted mouth opening. He scheduled for left inguinal hernia repair surgery.Discussion:The patient’s difficult airway was managed successfully and the anesthesia of his surgical procedure had an uneventful course.

Implant alignment is an important factor in overdentures retained by solitary abutments. In this study, the effect of implant angulations in two directions, on the amount of retention of attachments was evaluated. Ninety models were divided into nine groups of two blocks each; one for two implants and one for two attachments. The implants were placed either parallel to, at 5°, or at 10° relative to the reference plane. The attachments were related to the implants with a 0, 5, or 10° angulations. The direction of the implant was either labial or distolabial. The initial and the subsequent retention values of each sample were measured after each 500 cycles of insertion and removal. The measurements were repeated for five consecutive 3,000 cycles, and the results were analyzed by means of one-way ANOVA and Tukey HSD tests. Group 9 with a 10° distolabial tilt of the implants and of their attachments showed the highest initial retention, whereas group 1 with a 0° angulations and parallel attachments showed the lowest (6.9 ± 0.28 and 3.88 ± 0.19 N, respectively). The initial retention and the final loss of retention was significantly higher in those groups with the distolabial tilt of the implants (p < 0.05). Within the limitations of this study, it was demonstrated that the more divergent the implants and their retentive components, the higher their initial retention and the lower their final retention may be.