A physiological signal database of children with different special needs for stress recognition.

This study presents a new dataset AKTIVES for evaluating the methods for stress detection and game reaction using physiological signals. We collected data from 25 children with obstetric brachial plexus injury, dyslexia, and intellectual disabilities, and typically developed children during game therapy. A wristband was used to record physiological data (blood volume pulse (BVP), electrodermal activity (EDA), and skin temperature (ST)). Furthermore, the facial expressions of children were recorded. Three experts watched the children's videos, and physiological data is labeled "Stress/No Stress" and "Reaction/No Reaction", according to the videos. The technical validation supported high-quality signals and showed consistency between the experts.

Micro-CT evaluation of voids using two root filling techniques in the placement of MTA in mesial root canals of Vertucci type II configuration.

OBJECTIVE: The present study aims to compare two mineral trioxide aggregate (MTA) placement techniques, manual compaction and ultrasonic activation of manually compacted MTA, with warm vertical compaction (WVC) for orthograde obturation of mesial root canals of mandibular first molars showing Vertucci type II root canal configuration. MATERIALS AND METHODS: Thirty roots were selected according to their micro-CT scanned images. Root canals were chemomechanically prepared using Reciproc R25 and NaOCl using EndoVac. The specimens were divided into three groups according to the root canal filling technique, as manual compaction of MTA, ultrasonic activation of manually compacted MTA and WVC using gutta-percha and AH Plus (Denstply Sirona, Ballaigues, Switzerland). Percentages of voids located in apical 3 mm and remaining coronal half until the level where separate root canals re-join within filling were calculated. Data were analyzed using the Kruskal-Wallis and Dunn's tests, and significance was set at 5%. RESULTS: No significant difference was found among the filling techniques regarding the percentage volume of voids at apical 3 mm (P > 0.05). At the coronal half of the isthmus, WVC produced significantly less percentage volume of voids than manual compaction of MTA (P < 0.05) and similar to ultrasonic activation group did (P > 0.05). There was no significant difference between two MTA placement techniques at the coronal half of the isthmus (P > 0.05). CONCLUSIONS: No filling technique produced void-free fillings. The percentage of void volume was similar among groups at apical 3 mm but was different at the coronal half of the isthmus. CLINICAL RELEVANCE: Warm vertical compaction and ultrasonically activated MTA fillings revealed similar quality at the isthmus area, which was superior to manually compacted MTA.

Evaluation of marginal and internal adaptation of hybrid and nanoceramic systems with microcomputed tomography: An in vitro study.

STATEMENT OF PROBLEM: The accuracy of recently introduced chairside computer-aided design and computer-aided manufacturing (CAD-CAM) blocks is not well established, and marginal integrity and internal adaptation are not known. PURPOSE: The purpose of this in vitro study was to evaluate the marginal and internal adaptation of hybrid and nanoceramics using microcomputed tomography (µ-CT). MATERIAL AND METHODS: The marginal and internal adaptation of 3 polymer-infiltrated ceramic-network (PICN) materials (Vita Enamic [VE]; Lava Ultimate [LU]; Vita Suprinity [VS]) were compared with lithium disilicate (IPS e.max.CAD, IPS). Ninety-six specimens (48 dies and 48 crowns) were prepared (n=12 each group) using a chairside CAD-CAM system. The restorations were scanned with µ-CT, with 160 measurements made for each crown, and used in 2-dimensional (2D) analysis. The marginal adaptation of marginal discrepancy (MD), absolute marginal discrepancy (AMD), internal adaptation of shoulder area (SA), axial space (AS), and occlusal space (OS) were compared using appropriate statistical analysis methods (α=.05). Cement volumes were compared using 3D analysis. RESULTS: The IPS blocks showed higher MD (130 µm), AMD (156 µm), SA (111 µm) (P<.05), AS (52 µm), and OS (192 µm) than the other blocks (P<.01). The adaptation values of VS were significantly lower than those of the IPS block (P<.05). The adaption values of the LU and VE blocks were significantly lower than those of others (P<.01) but were statistically similar to one another (P>.05). IPS had the largest cement space at 18 mm3 (P<.01). CONCLUSIONS: The marginal and internal adaptation values were within a clinically acceptable range for all 3 hybrids and nanoceramics tested.

Effect of intracanal cryotherapy on pain after single-visit root canal treatment.

The purpose of this study was to evaluate the effect of 2.5°C cold saline irrigation as final irrigant on postoperative pain after single-visit root canal treatment of teeth with vital pulps. One-hundred and seventy patients were assessed as eligible and included to the study. The teeth were randomly divided into two groups (n = 85) (i.e. the control group and the cryotherapy group). In the cryotherapy group, final irrigation with 2.5°C 0.9% physiological saline solution for 5 min was performed following completion of biomechanical preparation, whereas in control group same solution stored at the root temperature was used. Treatments were performed in a single visit. Participants were asked to rate the intensity of their postoperative pain using visual analogue scale at 24 and 48 h. Data were analysed by Mann-Whitney U test and Student's t test. In the cryotherapy group level of reported postoperative pain was significantly lower than the control group (P < 0.05, Mann-Whitney U test). The outcome of this investigation indicates that 2.5°C cold saline irrigation as final irrigant can result a significant reduction in postoperative pain levels in comparison to the control group. Cryotherapy is a simple, cost-effective, and non-toxic option for postoperative pain control in single visit root canal treatment.

The sealing ability of novel Kryptonite adhesive bone cement as a retrograde filling material.

Background. This study evaluated the ability of Kryptonite bone cement in sealing retrograde cavities. Methods. The root canals of one hundred extracted human maxillary incisor teeth were instrumented up to master apical file #40 using Mtwo rotary system and obturated with gutta-percha and AHPlus sealer by cold lateral compaction method. The specimens were assigned to one control group and four experimental groups based on the retrograde filling materials (n=20). The specimens were immersed in 0.5% Rhodamine B solution for 48h. Then the specimens were divided longitudinally into two parts and the depth of dye penetration was assessed under ×10 magnification. Data were analyzed using one-way ANOVA and Bonferroni tests. Results. There were statistically significant difference between the experimental groups and the control group (P<0.05). There were no statistically significant differences between the experimental groups in dye penetration scores (P>0.05). Conclusion . Kryptonite cement provided optimal apical seal in a manner similar to MTA, amalgam and IRM when used as a retrograde filling cement.

Fracture Resistance of Endodontically Retreated Roots After Retreatment Using Self-Adjusting File, Passive Ultrasonic Irrigation, Photon-Induced Photoacoustic Streaming, or Laser.

OBJECTIVE: Additional cleaning techniques and devices are required to remove maximum amount of residual filling material, which might limit disinfection of root canal system during retreatment. This study aimed to compare fracture resistance of roots when self-adjusting file (SAF), photon-induced photoacoustic streaming (PIPS), passive ultrasonic irrigation (PUI), erbium-doped yttrium aluminum garnet (Er:YAG), or neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers are applied following the use of retreatment files in endodontics. MATERIALS AND METHODS: A total of 117 human mandibular canine teeth of similar dimensions were selected and divided into nine groups (n = 13). Aside from control, instrumented, and only-prepared groups, 91 teeth were remaining, of which 13 were assigned to the only-filling group and final 78 to retreatment, thus R-Endo file, R-Endo+SAF, R-Endo+PUI, R-Endo+Er:YAG laser, R-Endo+Nd:YAG laser, and R-Endo+PIPS. RESULTS: The fracture strengths of the retreatment groups were lower than control, instrumented, and only-filling groups (p < 0.05). There was no difference between the R-Endo group and additional retreatment procedure groups (p > 0.05). CONCLUSIONS: Further cleaning methods using SAF, PIPS, Er:YAG laser, Nd:YAG laser, or PUI did not decrease the fracture resistance when compared with the R-Endo group.

Scanning electron microscopy with energy dispersive X-ray spectrophotometry analysis of reciprocating and continuous rotary nickel-titanium instruments following root canal retreatment.

This study aimed to evaluate superficial defects and the composition of Reciproc R25 and ProTaper Retreatment file systems (Dentsply Maillefer, Ballaigues, Switzerland) used for retreatment. A total of 100 maxillary incisor teeth were randomly divided into the following two groups: Reciproc R25 (n = 25) and ProTaper Retreatment instrument (n = 75) groups. The nickel-titanium (Ni-Ti) compositions of the files before and after use were analyzed using energy dispersive X-ray spectrophotometry (EDX). Chi-square, Mann-Whitney U, and Kruskal-Wallis tests were used to analyze the data. ProTaper Retreatment instrument group showed a significantly higher number of defects than the Reciproc group (P < 0.05). No instrument fracture was detected. The presence of debris was observed in both groups before use, although the level was significantly higher in the ProTaper Retreatment group, which consisted of metals (P < 0.05). There was no significant difference between new and used instruments with regard to Ni-Ti composition (P < 0.05). EDX analysis showed that both the Reciproc and ProTaper Retreatment instruments had a Ni-Ti composition that was within the standards specified by the American Society of Testing and Materials. This study confirmed the use of both the Reciproc R25 file and ProTaper Retreatment file system for root canal filling removal in straight root canals as a safe procedure. (J Oral Sci 58, 401-406, 2016).

3D micro-CT analysis of void formations and push-out bonding strength of resin cements used for fiber post cementation.

PURPOSE: To investigate the void parameters within the resin cements used for fiber post cementation by micro-CT (µCT) and regional push-out bonding strength. MATERIALS AND METHODS: Twenty-one, single and round shaped roots were enlarged with a low-speed drill following by endodontic treatment. The roots were divided into three groups (n=7) and fiber posts were cemented with Maxcem Elite, Multilink N and Superbond C&B resin cements. Specimens were scanned using µCT scanner at resolution of 13.7 µm. The number, area, and volume of voids between dentin and post were evaluated. A method of analysis based on the post segmentation was used, and coronal, middle and apical thirds considered separately. After the µCT analysis, roots were embedded in epoxy resin and sectioned into 2 mm thick slices (63 sections in total). Push-out testing was performed with universal testing device at 0.5 mm/min cross-head speed. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests (α=.05). RESULTS: Overall, significant differences between the resin cements and the post level were observed in the void number, area, and volume (P<.05). Super-Bond C&B showed the most void formation (44.86 ± 22.71). Multilink N showed the least void surface (3.51 ± 2.24 mm(2)) and volume (0.01 ± 0.01 mm(3)). Regional push-out bond strength of the cements was not different (P>.05). CONCLUSION: µCT proved to be a powerful non-destructive 3D analysis tool for visualizing the void parameters. Multilink N had the lowest void parameters. When efficiency of all cements was evaluated, direct relationship between the post region and push-out bonding strength was not observed.

Push-out bond strength of oval versus circular fiber posts irradiated by erbium-doped yttrium aluminum garnet laser.

STATEMENT OF PROBLEM: Fiber posts in conjunction with resin cements are widely used to provide retention in endodontically treated teeth. The bond strength of restorative materials to root canal dentin is an important issue for the long-term success of restorative procedures. The push-out test is widely used to measure the bonding between the post and radicular dentin. PURPOSE: The purpose of this in vitro study was to evaluate the effect of erbium-doped yttrium aluminum garnet (Er-YAG) laser treatment of dentinal walls on the bond strength of circular and oval fiber posts luted in oval root canals. MATERIAL AND METHODS: Forty mandibular premolar teeth were endodontically treated and restored with 2 different intracanal post systems. Push-out tests were performed and data were analyzed by using 2-way analysis of variance and post hoc Bonferroni tests. RESULTS: Laser pretreatment of dentinal walls resulted in higher push-out bond strength than that of the nonlasered groups (P<.05). Oval fiber posts showed significantly higher push-out bond strength values than those of circular fiber posts in the coronal region (P<.05). In the apical region, no statistically significant difference was noted among the groups regarding push-out bond strength (P>.05). CONCLUSIONS: The laser pretreatment with an oval ultrasonic tip of an oval fiber post system improved bonding to root canal dentin when compared with a circular post system with conventional preparation.

The efficacy of laser, ultrasound and self-adjustable file in removing smear layer debris from oval root canals following retreatment: A scanning electron microscopy study.

This study aims to compare the efficacy of different irrigation activation methods to remove smear layer and debris from oval-shaped root canals following retreatment. Ninety mandibular canines with oval-shaped root canals were selected. Retreatment was performed with R-Endo retreatment files. The samples were randomly divided into six groups (n = 15). Groups were assigned according to agitation technique: R-Endo with classic irrigation, with self-adjustable file, with passive ultrasonic irrigation, R-Endo + Er:YAG, R-Endo + PIPS and R-Endo + Nd:YAG. Compared with the classic irrigation (R-Endo + CI) group, all other groups were more successful in reducing smear layer and debris (P < 0.05). The least amount of residual smear layer and debris was detected in the Er:YAG laser group (P < 0.05). Additional use of different agitation methods contributes to removal of debris and smear layer following root canal filling removal with rotary instruments; however, none of the techniques tested render root canal walls completely free of smear layer or debris.

Comparing the Effect of Different Voxel Resolutions for Assessment of Vertical Root Fracture of Permanent Teeth.

BACKGROUND: The teeth with undiagnosed vertical root fractures (VRFs) are likely to receive endodontic treatment or retreatment, leading to frustration and inappropriate endodontic therapies. Moreover, many cases of VRFs cannot be diagnosed definitively until the extraction of tooth. OBJECTIVES: This study aimed to assess the use of different voxel resolutions of two different cone beam computerized tomography (CBCT) units in the detection VRFs in vitro. MATERIALS AND METHODS: The study material comprised 74 extracted human mandibular single rooted premolar teeth without root fractures that had not undergone any root-canal treatment. Images were obtained by two different CBCT units. Four image sets were obtained as follows: 1) 3D Accuitomo 170, 4 × 4 cm field of view (FOV) (0.080 mm(3)); 2) 3D Accuitomo 170. 6 × 6 cm FOV (0.125 mm(3)); 3) NewTom 3G, 6˝ (0.16 mm(3)) and 4) NewTom 3G, 9˝ FOV (0.25 mm(3)). Kappa coefficients were calculated to assess both intra- and inter-observer agreements for each image set. RESULTS: No significant differences were found among observers or voxel sizes, with high average Z (Az) results being reported for all groups. Both intra- and inter-observer agreement values were relatively better for 3D Accuitomo 170 images than the images from NewTom 3G. The highest Az and kappa values were obtained with 3D Accuitomo 170, 4 × 4 cm FOV (0.080 mm(3)) images. CONCLUSION: No significant differences were found among observers or voxel sizes, with high Az results reported for all groups.

Evaluation on shear bond strength of different glass ionomer and hydroxy apatite cements used in ossiculoplasty.

BACKGROUND: Glass ionomer cements (GIC) have been widely used in dentistry for many years. In recent years, GIC have also been used for ossiculoplasty. The bond strength of GIC used in ossiculoplasty and the way they may change over the years in the cementation area are being questioned. The bonding strength of the substance may be of importance for long-term outcomes. AIMS: The aim of this study was to investigate the bond strength of different GIC on ossicles. STUDY DESIGN: In vitro study. METHODS: Twenty ossicles were obtained from patients who had undergone ear surgery. All specimens were randomly divided into four subgroups. All specimens were inserted into a specially designed apparatus for shear bond strength (SBS) testing. The tested materials [Aqua Meron (AM), Aqua Cem (AC), Ketac Cem (KC), and Otomimix CPB (OH)] were prepared and applied according to the manufacturer's instructions. The SBS was tested using a universal testing machine at a crosshead speed of 0.5 mm/min. RESULTS: The mean SBSs were found to be 13.28 MPa, 23.43 MPa, 8.51MPa, and 1.78 MPa for AM, AC, KC, and OH, respectively. AC had the highest SBS, which was statistically significantly different from that of KC and OH (p<0.05). Both AM and KC had higher SBS than OH (p<0.05). CONCLUSION: The results obtained in this study by investigating the bone-bonding strength of cements widely used in ossiculoplasty demonstrate that some of these substances have a greater ability to bond to ossicles compared to others. Further clinical investigations are needed to test different parameters.

Management of dens invaginatus type II with periapical lesion: case report.

Dens invaginatus is a developmental anomaly resulting from epithelial invagination of the tooth crown before calcification. Endodontic treatment of teeth affected by dens invaginatusmay be difficult and complex due to aberrant anatomy. Combined orthograde and surgical approaches for successful treatment of dens invaginatus are effective. This report describes the successful treatmentand results atthe 12-month follow-up of a maxillary lateral incisor showing dens invaginatus type II, a large periapical lesion and an open apex by using combined surgical and endodontic treatment.

Fracture resistance of endodontically treated roots with oval canals restored with oval and circular posts.

INTRODUCTION: The aim of the present study was to evaluate the effects of post space preparations with circular and oval post drills and the placement of oval and circular posts on the fracture strength of roots with oval canals. METHODS: Seventy mandibular premolars with oval root canals were decoronated. Fourteen teeth were used as a control group (group 1), and the root canals of the remaining teeth were prepared up to size #30. The root canals were filled, and the samples were randomly divided into 4 experimental groups as follows: post space preparation with circular-shaped drills (group 2), post space preparation with oval-shaped drills (group 3), circular post placement (group 4), and oval post placement (group 5). A fracture strength test was performed on each specimen, and the data were statistically evaluated using 1-way analysis of variance and Tukey post hoc tests. RESULTS: The fracture strengths of the circular posts-placed group were higher than those of the oval post-placed group (P < .001). The post space preparation using oval-shaped drills significantly decreased the fracture strength of the roots compared with the control group (P < .001). CONCLUSIONS: Within the limitations of the present study, oval posts did not provide a higher fracture resistance to endodontically treated roots with oval canals compared with circular posts. Therefore, clinicians should be aware that oval posts are similar to circular posts in terms of enhancing the fracture resistance of roots with oval canals.

Comparison of intraoral radiography and cone-beam computed tomography for the detection of horizontal root fractures: an in vitro study.

OBJECTIVES: This study aimed to compare the diagnostic accuracy of two different cone-beam computed tomography (CBCT) units with several intraoral radiography techniques for detecting horizontal root fractures. METHODS: The study material comprised 82 extracted human maxillary incisors without root fractures that had not undergone any root canal treatment. Root fractures were created in the horizontal plane in 31 teeth by a mechanical force using a hammer with the tooth placed on a soft foundation as described in a previous study. The teeth were divided into two groups: a control group with no fractures and a test group with fractures. These were randomized to the empty maxillary anterior sockets of a dry human maxilla. Each tooth was imaged at various vertical angles using each of the following modalities: a 3D Accuitomo 170 CBCT, a NewTom 3G CBCT, a VistaScan PSP, a CCD sensor, and conventional film. Specificity and sensitivity for assessing horizontal root fracture by each radiographic technique were calculated. Chi-square statistics were used to evaluate differences between modalities. Kappa statistics assessed the agreement between observers. Results were considered significant at P < 0.05. RESULTS: The kappa values for inter-observer agreement between observers ranged between 0.88 and 0.98 for the 3D Accuitomo 170, 0.82 and 0.91 for the NewTom 3G, and 0.61 and 0.72 for the different types of intraoral images. The diagnostic accuracy for detecting fracture lines in 3D Accuitomo 170 (0.93) was significantly higher than NewTom 3G (0.87), VistaScan (0.71), CCD (0.70), and CF (0.68). CONCLUSIONS: 3D Accuitomo 170 has the highest sensitivity and diagnostic accuracy for detecting horizontal root fracture among the 5 radiographic modalities examined. CBCT should be considered as the most reliable imaging modality of choice for the diagnosis of horizontal root fracture. CLINICAL RELEVANCE: CBCT imaging offers the clear advantage over conventional imaging that traumatized teeth can be visualized in all three dimensions--especially the oro-facial dimension.

Quality of different gutta-percha techniques when filling experimental internal resorptive cavities: a micro-computed tomography study.

The purpose of this ex vivo study was to determine the quality of root fillings in experimental internal resorptive cavities filled using cold lateral condensation (CLC), vertical condensation and Thermafil techniques. Forty-five extracted maxillary canine teeth were selected. After root canal instrumentation, the roots were sectioned horizontally and experimental internal resorption cavities were prepared. The root sections were re-approximated with a luting agent and randomly assigned to three groups (n = 15) to be filled using CLC, vertical condensation and Thermafil, respectively. Assessment of obturation quality in the internal resorptive cavity was performed using a desktop X-ray micro focus computed tomography scanner, and the percentage of gutta-percha (GP), sealer and voiding was calculated for each specimen. Data were statistically analysed using non-parametric tests, with P < 0.05 denoting a statistically significant difference. Vertical condensation filled 96.25 ± 8.31% of the total artificial cavity, and was superior to CLC (63.20 ± 16.87%) and Thermafil (59.26 ± 18.47%). The mean percentage of voids was 3.75 ± 8.31% in the vertical condensation group, 37.09 ± 17.13% in the CLC group and 41.06 ± 18.60% in the Thermafil group. We conclude that obturation of experimental resorption cavities is significantly better when using vertical condensation than when using other GP-based techniques.

In vitro evaluation of long-term cytotoxic response of injection-molded polyamide and polymethyle metacrylate denture base materials on primary fibroblast cell culture.

OBJECTIVE: This study investigated the long-term cytotoxic response of thermoplastic polyamide and conventional polymethyle metacrylate (PMMA) denture base materials. MATERIALS AND METHODS: Twenty discs were prepared for each polyamide, heat and cold cured PMMA denture base resins (totally 60) and divided into four sub-groups (n = 5). Cytotoxicity was assessed with the direct cell contact method using cell viability and neutral red (NR) uptake assay. Each sub-group was tested at initial and after being aged for 24 h, 1 week and 8 weeks with artificial saliva according to ISO 10993 standards. RESULTS: There were no significantly difference among the materials and control groups after initial, 24 h and 1 week testing. In 24 h testing, only Deflex was more toxic according to the Control group (p < 0.05). After 8 weeks of aging with artificial saliva, all materials were significantly cytotoxic when compared to the control group. QC20 was more toxic than Deflex and SC Cold Cure (p < 0.05). There were significant differences between the 8 week aging group and the initial, 24 h and 1 week testing for all materials (p < 0.05). CONCLUSIONS: Cytotoxicity of all tested denture base materials increased significantly after the long-term aging. Therefore, long-term aging may be useful to determine a dental material's toxicity. Polyamide denture base material had a similar toxicity profile with conventional heat- and cold-cured PMMA.

Bond strength of resin cement to yttrium-stabilized tetragonal zirconia ceramic treated with air abrasion, silica coating, and laser irradiation.

OBJECTIVE: The purpose of this study was to evaluate the shear bond strength of a resin cement to yttrium-stabilized tetragonal zirconia (Y-TZP) surfaces treated with air abrasion, silica coating, or CO(2), Er:YAG, or Nd:YAG laser irradiation, or irradiated by each laser after air abrasion. BACKGROUND DATA: Optimized methods are needed to improve the adhesive bonding between resin cement and Y-TZP ceramic. METHODS: Twelve specimens were irradiated with each laser at different parameters and examined by scanning electron microscopy to determine which parameters to use in this study. One hundred forty-one Y-TZP discs were assigned to nine groups: C, no treatment; AA, air abrasion; CJ, silica coating; ER, Er:YAG laser; ND, Nd:YAG laser; CO, CO(2) laser; AA+ER, air abrasion + Er:YAG laser; AA+ND, air abrasion + Nd:YAG laser; AA+CO, air abrasion + CO(2) laser. The composite cylinders were fabricated. After the surface treatments, the specimens were silanized and composite cylinders were cemented with the resin cement. The shear bond strength test was performed after specimens were stored in water for 24 h and after thermocycling for 500 cycles. RESULTS: The highest bond strength was obtained in the AA group and was similar to that of the CJ group. In C, ER, CO, ND, AA+ND, and AA+CO groups, the shear bond strengths were similar to each other according to the Duncan test results. The lowest bond value was obtained in the AA+ER group. CONCLUSION: Although air abrasion and silica coating were the most effective surface treatment methods, CO(2) and Er:YAG laser irradiation alone or Nd:YAG laser irradiation after air abrasion may be used as an alternative treatment method to increase the bond strength between resin cement and Y-TZP material.