Search

Objective The aim of this study was to evaluate the influence of different marginal designs (deep chamfer, vertical, and modified vertical with reverse shoulder) on the fracture strength and failure modes of monolithic zirconia crowns. Materials and Methods Thirty sound human maxillary first premolar teeth with comparable size were used in this study. The teeth were divided randomly into three groups according to the preparation design (n = 10): (1) group A: teeth prepared with a deep chamfer finish line; (2) group B: teeth prepared with vertical preparation; and (3) group C: teeth prepared with modified vertical preparation, where a reverse shoulder of 1 mm was placed on the buccal surface at the junction of middle and occlusal thirds. All samples were scanned by using an intraoral scanner (CEREC Omnicam, Sirona, Germany), and then the crowns were designed by using Sirona InLab 20.0 software and milled with a 5-axis machine. Each crown was then cemented on its respective tooth with self-adhesive resin cement by using a custom-made cementation device. A single load to failure test was used to assess the fracture load of each crown by using a computerized universal testing machine that automatically recorded the fracture load of each sample in Newton (N). Statistical Analysis The data were analyzed statistically by using one-way analysis of variance test and Bonferroni test at a level of significance of 0.05. Results The highest mean of fracture load was recorded by chamfer (2,969.8 N), which followed by modified vertical (2,899.3 N) and the lowest mean of fracture load was recorded by vertical (2,717.9 N). One-way ANOVA test revealed a significant difference among the three groups. Bonferroni test showed a significant difference between group A and group B, while a nonsignificant difference was revealed between group C with group A and group B. Conclusion Within the limitations of this in vitro study, the mean values of fracture strength of monolithic zirconia crowns of all groups were higher than the maximum occlusal forces in the premolar region. The modification of the vertical preparation with a reverse shoulder placed at the buccal surface improved the fracture strength up to the point that it was statistically nonsignificant with the chamfer group.

AIM AND OBJECTIVE To evaluate and compare the ability of three commercially available remineralizing agents on the surface microhardness (SMH) of enamel after induction of white spot lesions (WSLs) by demineralization. MATERIALS AND METHODS About 80 sound mandibular human premolars that were later removed as a part of orthodontic treatment were employed in this research under the inclusion criteria. After cleaning and disinfecting the teeth, their crowns were mounted in acrylic resin and painted with nail varnish, not including a 3 mm × 3 mm window in the middle of the buccal surface. Each tooth was soaked in 15 mL of a demineralizing solution at a pH of 4.5 that was prepared for this study and left in a place for 10 subsequent days to permit the formation of WSLs after which the SMH was again assessed. The premolar teeth were then randomly allocated and equally divided into one of the four groups of 20 each depending on the treatment they received as Group 1: control group, Group 2: Colgate sensitive Pro-Relief toothpaste group, Group 3: Amflor group, and Group 4: Enafix group. After 15 days, the microhardness of all samples was estimated and alterations in the same were noted. Scanning electron microscopy (SEM) was used to evaluate the surface morphology. RESULTS Enhanced and highest mean SMH was present in the Colgate sensitive Pro-Relief group (53.26 ± 0.10) followed by Enafix group (47.72 ± 0.21), Amflor group (44.84 ± 0.66), and control group (39.52 ± 0.32), respectively after application of remineralizing agents. Except for Group 3 vs Group 4, statistically significant differences (p < 0.05) were noted in all the groups. CONCLUSION All the three agents employed in this study, that is, Colgate sensitive Pro-Relief toothpaste, Amflor, and Enafix improved the SMH of teeth after the therapy given over 15 days compared to the microhardness following demineralization. CLINICAL SIGNIFICANCE White spot lesions often occur on labial surfaces of teeth after orthodontic treatment. Hence, these lesions pose esthetic challenges thereby affecting treatment satisfaction perceived by the patient. As esthetics and appearance are of foremost significance after orthodontic treatment, elimination protocols for remineralization of WSLs are of utmost importance employing economic means. How to cite this article: Nalawade VA, Jeri SY, Dash BP, et al. Effectiveness of Various Remineralizing Agents on White Spot Lesions after Orthodontic Treatment: A Comparative Study. J Contemp Dent Pract 2021;22(5):545-548.

It is claimed that a hydrophilic primer, called the moisture insensitive primer (MIP), can be used with both dry and wet enamel surfaces. This study sought to assess the shear bond strength (SBS) of APC Plus adhesive coated appliance system to enamel using MIP in wet and dry conditions.This in vitro experimental study evaluated 24 extracted maxillary premolars with intact buccal enamel. The teeth were randomly divided into two groups (n=12), and APC Plus premolar brackets were bonded to their buccal surface using moisture insensitive primer (MIP) under wet and dry enamel conditions. The SBS values were measured by a universal testing machine. The adhesive remnant index (ARI) score was also determined under a stereomicroscope. Data were analyzed using t-test and Mann-Whitney test at P0.05 level of significance.The SBS in wet condition was significantly lower than that in dry condition (mean value of 18.37MPa versus 25.5MPa, P0.001). The two groups had no significant difference regarding the ARI scores (P0.05). However, in both groups, less adhesive was left on the tooth surface. This suggests that bond failure occurred at the adhesive-enamel interface.APC Plus adhesive coated appliance system in combination with hydrophilic MIP can be effective in clinical conditions with high risk of moisture contamination.

Objectives To evaluate the volume, amount, and localization of root resorption in the upper first premolars by micro–computed tomography (micro-CT) after three different rapid maxillary expansion appliances and two different activation rhythms. Materials and Methods The patients were divided into three groups; Hyrax, acrylic cap splint (ACS), and full coverage acrylic bonded (FCAB) appliances. Each group was then divided into the following two subgroups: rapid maxillary expansion (RME) and semirapid maxillary expansion (SRME). After expansion was completed, the appliances were stabilized for 12 weeks during the retention period. For each group, 10 premolars (for a total of 60 premolars) were scanned with the micro-CT (SkyScan). The reconstructed 3D images of each root sample were divided into six regions. The resorption craters on these six different root surfaces were analyzed by special CTAn (SkyScan) software for direct volumetric measurements. Kruskal-Wallis one-way analysis of variance and Mann-Whitney U tests were used for statistical analysis. Results The total volume of root resorption was less with FCAB than with ACS and Hyrax (P < .001). In all groups, a greater volume of resorption was found on the buccal surface than on the lingual surface (P < .001). No significant differences were found between the RME and SRME groups (P > .05). Conclusions All expansion appliances caused root resorption in the upper first premolar teeth, but FCAB may be safer in terms of root resorption. The resorption craters were generally concentrated on the buccal surface. There was no effect of activation rhythm on root resorption.

Enamel demineralization and white-spot lesions (WSLs) around the orthodontic brackets are common clinical complications after orthodontic fixed appliance therapy. WSLs form mainly due to plaque deposition around the brackets during the orthodontic treatment period. This study was designed to compare and evaluate the efficacy of two different remineralization agents on WSLs, which are “Clinpro 5000 and Colgate Sensitive Pro-Relief”. 27 caries-free human premolar teeth were collected after extraction for orthodontic purposes. The crowns were set in acrylic resin, and the entire surfaces were coated with nail varnish apart from an area of 4 × 4 mm on the buccal surface. The surface microhardness (SMH) was measured using the Vickers microhardness testing machine at baseline, after demineralization, and after treatment. Then, the different SMH values were statistically analyzed using mixed-effects linear regression. All samples were immersed in demineralizing solution for ten days to create WSLs, and then the teeth were allocated randomly into one of the three groups: Group 1 (control group-immersed in artificial saliva), Group 2 (treated with Colgate sensitive Pro-Relief toothpaste), and Group 3 (Clinpro 5000 toothpaste). Cycles of treatment were done for 5 minutes every 12 hours for 14 days. The samples were stored in freshly prepared artificial saliva between cycles. The mixed-effects model was used to quantify the effect of different remineralization agents. All statistics were computed using STATA software (version14.1; Stata, College Station, TX). All statistical tests were two-tailed and interpreted at the 0.05 significance level. Both agents improved the surface hardness. Clinpro 5000 improved the surface hardness by 12.7 ( P value 0.012), and Colgate Sensitive Pro-Relief improved surface hardness by 18.2 ( P value

Background: Microleakage is a concern while restoring cervical lesions. Many products have attempted to minimize the interfacial gap between the tooth and restoration, the main pathway of microleakage. Aims and Objective: To compare and evaluate the microleakage in Class V cavity restored with nanohybrid flowable composite, Resin modified Glass Ionomer and Cention N. Method: Class V cavities were prepared on mandibular premolars on buccal surface with their occlusal margin placed in enamel and the gingival margin in dentin. The teeth were randomly assigned to three groups of 20 teeth each and restored with Flowable composite , Resin Modified GIC and Cention N. Samples were immersed in 0.5% Rhodamine dye, sectioned and microleakage measured using Confocal Laser Scanning Microscopy. Statistical analysis was done using Oneway ANOVA Bonferroni's test and Kruskal Waliis test. Results: The average depth of penetration of dye and scoring of depth were noted. On comparing dye penetration values between groups, RMGIC is compared with Flowable composite and Cention N, statistically significant result was obtained suggesting lesser dye penetration in RMGIC group (P < 0.001) where other comparison did not. Conclusion: RMGIC showed significantly less microleakage compared to the other two restorative materials used in the study and enamel margin of all restorations showed lesser microleakage than dentin margin.

Solitary fibrous tumor (SFT), an uncommon spindle cell neoplasm is believed to be of mesenchymal origin and usually presents as pleural based mass. SFT are rare in the head-neck region but are extremely uncommon intra-orally. The patient was a young male who presented with difficulty in mouth opening. Examination revealed a submucosal nodule on the buccal surface which was histologically and immunohistochemically proven to be SFT. Authors wish to discuss the case due to its rarity and diagnostic difficulties due to many common histological mimickers at that site.

Title: Spectrophotometric assessment of tooth discoloration induced by various Antibiotic pastes. Aim: To evaluate tooth discoloration induced by various Antibiotic pastes using spectrophotometer. Materials and Methods: Sixty extracted upper front tooth were selected for the study. Access opening was done and root canal of each tooth was instrumented with hand files. The tooth were then randomly divided into 3 groups: Group A (Triple antibiotic paste: Ciprofloxacin+ Metronidazole+Minocycline), Group B (Modified Triple antibiotic paste: Ciprofloxacin+ Metronidazole+ Clindamycin) and Group C (Double antibiotic paste: Ciprofloxacin+ Metronidazole). In all the groups, medicaments were only applied inside the root canals of the teeth and access cavity was sealed with cotton pellet and temporary restoration. Spectrophotometric readings were obtained from buccal surface of the teeth immediately after placing the medicaments (Baseline data) and at 1 week and after 2 months. Based on spectrophotometric readings at different time interval, ∆E was then calculated. Data were analyzed using 2-way (ANOVA) tests. Results: The maximum color change (ΔE) was observed at 2 months with Triple antibiotic paste (p < 0.0001) followed by Modified Triple antibiotic paste. No significant color change was noted with Double antibiotic paste. Conclusion: Antibiotic paste should be used judiciously inside the root canals of teeth to eliminate chronic root canal infection due to risk of tooth discoloration. Double antibiotic paste is a more promising option.

Purpose The aim of this pilot study is to investigate bone regeneration in a three wall defect during immediate implant placement, using porous biphasic calcium phosphate (BCP) granules with or without recombinant human bone morphogenetic protein – 2 (rhBMP-2). Materials and Methods Alveolar defects were created in the mandible of five female, adult micropigs. The lower right 4th premolar was extracted and the buccal cortex removed. Immediate implants were placed and the defect was grafted. Control group (n = 2), received BCP granules and fibrin sealant. The test group (n = 3) received BCP granules in combination with fibrin sealant and rhBMP-2. A collagen membrane was placed over the graft and primary closure of the wound was achieved. The pigs were all euthanized at 6 months after the first surgery. Histology evaluation and histomorphometry analyses calculating % bone implant contact (%BIC) and % bone area (%BA) were performed. Results One pig in the BMP group died prematurely at 3 months after the first surgery. At specimen harvest, there were no dehiscence of all surgical sites and implant survival rate was 100%. The control group demonstrated no new bone formation at the buccal surface of the dental implants at 6 months. The mean %BIC for the BMP group at 6 months was 75.53 ± 12.52%. The mean %BA for the BMP group 6 months was 52.82 ± 3.27%. Conclusion Within the limitations of this pilot study, the use of rhBMP-2 resulted in significant new bone formation in a non-contained defect around an immediate implant.

Background: Periodontal regeneration using complementary and alternative medicine has gained considerable attention recently. Propolis is a resinous hive product collected by honey bees from exudates and buds of plants and mixed with wax and bee enzymes.Objective: The aim of this study was to evaluate the effect of propolis as bone graft substitute in the management of experimental grade II furcation defects, and to compare its effect to nanobone and to Propolis/nanobone mixture. Material and Methods: Sixteen critical-sized furcation defects on the buccal surface of mandibular third and fourth premolars were surgically created in twelve dogs and divided into three groups. Group I; defects were filled with Propolis, Group II; defects were filled with nanohydroxyapatite graft and Group III; defects were filled with a combination of Propolis/ nanohydroxyapatite graft. Histologically and histomorphometric analysis of newly formed interradicular bone height and percentage were performed after one and three months. Results: After one month; the three experimental groups revealed the features of early periodontal tissues regeneration including cementum, newly formed bone with inserted newly formed PDL fibers. The propolis group showed the highest bone height and bone surface area. After three months; denser bone occupying larger surface area of the furcation defect were noted especially in the propolis group. Conclusion: The addition of nanobone to propolis showed better results than nano bone alone especially at early healing stage. However, it didn’t show better results than the use of propolis alone.

Aim: To histopathologically evaluate the pulpal healing after direct pulp capping with TotalFill and compared it with Neo MTA Plus in human tooth cultures. Methods: Forty sound human premolars freshly extracted for orthodontic reasons were randomly assigned to two experimental groups; group I: TotalFill and group II: Neo MTA Plus. Standardized Class V cavities were prepared on the buccal surface of each tooth where the pulp exposure was performed with a dental explorer. The pulp-exposed teeth were immediately capped with one of the tested materials. The prepared cavities were then finally restored with glass-ionomer cement. Teeth were cultured for three weeks and three months. Then, the cultured teeth were demineralized, sectioned and stained for histopathological evaluation. Data collected and statistically analyzed by using Fisher's exact test. The significance level was set at P ≤ 0.05. Results: Histopathological analysis showed complete dentin bridge formation and an absence of inflammatory pulp response. Statistical analysis showed no significant differences between the TotalFill and Neo MTA Plus groups during the observation periods. However, a significantly higher thickness of the dentin bridge was found in the group of teeth treated with TotalFill at three months. Conclusions: TotalFill produced similar favorable pulp healing and repair, and were comparable to Neo MTA Plus. Furthermore, TotalFill can form a thicker dentin bridge compared with Neo MTA Plus. Keywords: Bioceramics, Direct pulp cap, Histology, Human, Neo MTA Plus, TotalFill

Background and objectives Differences in dental maturation may affect the prognosis and clinical management of traumatized teeth. However, evaluation of the outcomes of dental trauma to the tooth and support structures in an in vivo model involves major methodological and ethical implications. Thus, the aim of the present study was to perform a three-dimensional finite element analysis of permanent maxillary central incisors in different stages of root development under different trauma settings. Methods The study factors included two trauma conditions (B, buccal; I, incisal) on upper permanent central incisors showing three different stages of root development (CR, complete rhizogenesis; IRA; incomplete rhizogenesis in the apical third of the root; and IRM, incomplete rhizogenesis in the middle third of the root) to yield six models. The complete rhizogenesis model was obtained with a cone-beam computed tomography examination of an extracted tooth. The two incomplete rhizogenesis models were modeled on the basis of similar examinations of patients. Trauma was simulated by applying a 300 N static surface to surface load on the incisal edge or perpendicular to the buccal surface of the tooth. The displacement and equivalent von Mises (σvM) stress values were obtained for alveolar bone, periodontal ligament, apical papilla, and dentin for the quantitative analysis. A σvM color-coded scale was used for qualitative analysis. Results The force direction had a greater influence on the stress than the root-formation stage. Buccal forces resulted in higher stress concentration in the bone and periodontal ligament, especially in B-CR. Lower stress was found on the periodontal ligament as the root formation progressed (decrease of 8% from B-IRA to B-CR and 11% from B-IRM to B-CR). The incomplete rhizogenesis models showed higher σvM stress peak values in dentin in comparison with complete rhizogenesis (increase of 52% from B-CR to B-IRA and 56% from B-CR to B-IRM). Conclusions Buccal forces yielded greater stress values regardless of the stage of rhizogenesis. Teeth with fully formed roots showed a higher stress concentration in the alveolar bone and periodontal ligament in comparison with immature teeth, with the latter presenting high stresses in the tooth crown.

“AIM: To assess the effect of three lining materials; flowable composite, flowable compomer, and light-curing glass ionomer cement (LCGIC) on microleakage in Class V restoration using packable composite restorations. MATERIALS AND METHODS: A standardized class V cavity was prepared on buccal surface of 40 young premolar teeth with the cervical margin extending 0.5 mm below the cementoenamel junction, into the dentin. All the samples were randomly divided into 4 groups according to the lining material used: Group I- Control; Group II- flowable composite; Group III- LCGIC and Group IV- flowable compomer. The restored teeth were thermocycled and immersed in 2% methylene blue solution for 24 hours. Each tooth was then sectioned along buccolingual direction. The dye penetration of the occlusal and gingival margins of each section was evaluated by a single observer using a stereomicroscope and statistically analyzed using Kruskal Walis Test and Mann-Whitney U Test. RESULT: Maximum dye penetration score for Group 1, Group 2 was 3 and Group 3, Group 4 was 1. (p

Background It has been demonstrated in non-oral tissues that the locally evoked vasoconstriction could elicit remote vasoconstriction. This study aimed to investigate the spreading vasoconstrictor effects of epinephrine in the gingiva. Methods Gingival blood flow (GBF) was measured by laser speckle contrast imager in 21 healthy volunteers. In group A, two wells were fabricated from orthodontic elastic ligature and placed 2 mm apically to the free gingival margin at the mid buccal line of 12 (test side) and 21 (control side) teeth. The GBF was measured in the wells and tightly apical, coronal, distal and mesial to the wells. In group B, the wells were made on the buccal surface of the same teeth, including the gingival sulcus. Four regions were selected for measurement from the gingival margin reaching the mucogingival line (coronal, midway1, midway2 and apical). After the baseline recording, 3 µg epinephrine was applied into the test, and physiological saline into the control well. The GBF was recorded for 14 min. The gingival thickness was measured with a PIROP Ultrasonic Biometer. Results In group A, the GBF did not increase or decrease after the application of epinephrine. In group B, the GBF significantly decreased in all regions of the test side and remained low for the observation period. The vasoconstriction appeared with delays in more apical regions (at min 1 in the coronal and the midway1, at min 2 in the midway2, at min 4 in the apical region). Similarly, the amount of the decrease at 14 min was the largest close to sulcus (− 53 ± 2.9%), followed by the midway1 (− 51 ± 2.8%) and midway2 (− 42 ± 4.2%) and was the lowest in the apical region (− 32 ± 5.8%). No correlation was found between GBF and gingival thickness. Conclusion Epinephrine could evoke intense vasoconstriction propagating to the mucogingival junction, indicating the presence of spreading vasoconstriction in the human gingiva. The attached gingiva is impermeable to epinephrine, unlike the gingival sulcus. This trial was registered in ClinicalTrials.gov titled as Evidence of Spreading Vasoconstriction in Human Gingiva with the reference number of NCT04131283 on 16 October 2019. https://clinicaltrials.gov/show/NCT04131283

Objective: The present study assessed the fracture strength of teeth subjected to endodontic access cavity preparation on buccal surfaces, or with the aid of operating microscopy when compared to the conventional technique. Material and methods: Sixty mandibular incisors were split into four groups (n=15): conventional access cavity preparation (CCP); conservative (C); buccal surface (BS); and control. The canals were prepared and filled and the cavities were restored. A static compressive strength test was conducted until crown fracture. The force data were compiled and assessed statistically. Kolmogorov-Smirnov and Shapiro-Wilk tests were performed to assess normality, Levene’s test to assess variance homogeneity, the one-way ANOVA to compare fracture strength in the assessed groups. Tukey’s HSD test was used to determine whether the differences in the means were significant between the groups.Results: The experimental groups did not show any statistically significant differences in mean fracture strength (CCP = 585.65 N±107.64 N)(BS = 530.52 N±129.35 N) (C = 517.83 N±114.68 N). Conclusion: Therefore, the selection of surface or size of access cavity proposed did not influence the fracture strength of mandibular incisors when compared to conventional cavity preparation. KeywordsDental pulp cavity; Dental stress analysis; Root canal therapy.

This study was carried out to evaluate the effect of acid etching versus laser etching of dentin surface on the bonding of Composite and Compomer restorative materials to dentin surface by studying microleakage at the dentin-filling interface, compositional analysis of dentin surface, and Scanning Electron Microscopic (SEM) study of the bonding area. 120 freshly extracted premolar teeth were divided according to surface treatment into three groups. Group I (Acid etching group) contained thirty teeth. Twenty teeth were selected to assess microleakage by forming standardized class V cavity on the buccal surface of the selected teeth. Then, teeth were subdivided into two subgroups with 10 teeth in each. Subgroup (i) delivered composite filling while subgroup (ii) delivered compomer filling according to manufacturer instructions. microleakage at the dentin-filling interface of teeth was examined using dye penetration method. dye penetration scores at occlusal and gingival margins were recorded and tabulated. Five dentin surfaces of five teeth from group I were etched by acid then prepared for compositional analysis of dentin surface by Infra-Red (IR) Spectroscopy. Another Five dentin surfaces were etched by acid then prepared for (SEM) assessment. Group II (Laser etching group) contained ninety teeth, twenty teeth were used for assessing microleakage after laser etching taking similar steps to that of acid etching. Thirty dentin surfaces of thirty teeth were etched by laser with different parameters then prepared for compositional analysis of dentin surface by IR Spectroscopy. Thirty dentin surfaces of thirty teeth were etched by laser with different parameters then prepared for SEM assessment. Group III (Untreated group) contained ten teeth that were left untreated. Five dentin surfaces of five teeth were subjected to IR Spectroscopy assessment. Five dentin surfaces of five teeth were prepared for SEM assessment. The results revealed that acid etching of dentin surface resulted in significant less leakage compared to laser etching. IR Spectroscopy revealed changes in dentin surface structure indicating that there was a reaction occurred by the acid and laser etching. SEM assessment showed more openings of dentinal tubules in case of acid etching, while in case of laser etching, there were a surface structural changes with a melting and fusion dentin surface. Acid etching of dentin gives better results on the bonding of Composite and Compomer filling materials than laser etching and thus gives more successful clinical condition. Further investigations are needed by using different types of laser to get more benefit from applications of laser clinically.

AIM To evaluate the effectiveness of CO2 laser treatment before applying 1.23% acidulated phosphate fluoride (APF), through topically applied 1.23% APF solution, and after applying 1.23% APF on acid resistance and fluoride uptake of the enamel. MATERIALS AND METHODS Sixty non-carious human premolars were extracted due to the orthodontic reason and stored in distilled water solution under refrigeration. Using a water-cooled diamond disc, enamel slabs of 4 mm × 4 mm × 1.5 mm were cut from the buccal surface of each tooth. Sixty samples were randomly divided into one control group and five test groups of 10 premolars each. Solution was prepared for wet chemical analysis followed by fluoride analysis that was carried out using a fluoride ion selective electrode (Thermo Scientific Orion 4-Star Plus ISE Meter). The weight of enamel (WE) was determined from the amount of calcium (Ca) etched away considering the fact that the Ca content of the human enamel is 37.4 wt%. The subgroups were statistically analyzed using ANOVA for fluoride determination and evaluation of acid resistance. RESULTS There was a significant increase in acid resistance of enamel slabs when treated individually or in combination of a low-power CO2 laser and 1.23% APF solution. Application of 1.23% APF solution after low-power CO2 laser treatment showed maximum increase in acid resistance. CONCLUSION Application of a low-power pulsed CO2 laser through topically applied 1.23% APF solution resulted in a detrimental effect of the human tooth enamel with resultant decrease in acid resistance. High fluoride uptake does not necessarily indicate increased acid resistance. CLINICAL SIGNIFICANCE The present study provides evidence that a low-power CO2 laser can be used effectively in combination with topically applied 1.23% APF solution in order to make the enamel more resistant to acid attack, thereby helping in controlling dental caries.

Aim This study evaluated the influence of the resin composite and bonding strategy on the push-out bond strength of the self-adhesive, Fusio liquid dentin (FUS) (Pentron Clinical), and of two conventional resin composites of different viscosities, Filtek Z250 (3M ESPE) and tetric flow (Ivoclar Vivadent). Materials and methods Thirty-two bovine incisors were used after disinfection. The roots were sectioned and the buccal and lingual surfaces were polished until a 2-mm slab was achieved, maintaining enamel at the buccal surface and dentin at the lingual surface. Standardized cavities were then prepared (2.0 × 1.5 mm) and restored according to the following bonding strategies: Fusio liquid dentin with selective etching (FUSSE) in enamel, FUS, Filtek Z250, and tetric flow-total etching (TET). All groups were restored in bulk. After 24 hours of storage in distilled water, finishing and polishing were performed. The push-out test was conducted on a universal testing machine (0.05 mm/minute). Data were analyzed through Kruskal-Wallis and Mann-Whitney tests (p = 0.05). The extruded restorations were evaluated under a stereomicroscope (10×) for failure-mode evaluation. Results There were no statistically significant differences between the groups TET, Z250, and FUS, with 145.59, 108.91, and 104.12 MPa means, respectively. The FUSSE group (40.92 MPa) showed a statistically significant lower bond strength. The predominant failure mode was a mixed failure for all groups. Conclusion The self-adhesive resin composite achieved a satisfactory result on bond strength when compared to conventional composites with regular and low viscosities, except when selective enamel etching was done. Clinical significance This study shows that the clinicians must be aware of the viscosity of the phosphoric acid to avoid dentin contamination whenever performing selective enamel etching. And the self-adhesive resin composite studied presented as another restorative alternative.

Background: This study investigated the effect of two different methods of bleaching during orthodontic treatment on bracket bond strength. Materials and Methods: A total of 45 extracted premolar teeth were selected in this experimental study and divided into three groups (office bleaching with 35% hydrogen peroxide, home bleaching with 22% carbamide peroxide, and control). The color of the teeth was assessed initially before the application of bleaching agents and Thermocycling. Orthodontic brackets were subsequently bonded on the treated surfaces. Bleaching procedures were then performed. A final color measurement was performed at two points on the buccal surface both underneath and adjacent to the bracket base. The initial and final color measurements and the bond strengths were compared between the groups using the analysis of variance. P < 0.05 was considered as statistically significant. Results: Bracket bond strength was significantly reduced in both bleaching groups compared with the control group (P < 0.01). The color difference before and after the bleaching procedures was significant in the office bleaching group (P < 0.01), while the control group did not demonstrate a statistical difference between initial and final color assessments (P > 0.05). Conclusion: Bleaching procedures performed during orthodontic treatment reduce bond strength. Enamel beneath the bracket base experiences a whitening effect though to a lesser degree compared with an uncovered surface.

This study evaluated the interference of enamel and coronal dentin thickness and ambient light in pulse oximetry interpretation, using SaO2the human finger as a reference. Forty-two intact human permanent mandibular molars were sectioned mesiodistally in the central portion. Buccal and lingual dentin surfaces were drilled, and 4 mm, 3 mm and 2 mm enamel/dentin thicknesses were interposed between finger and device, after which SaO2 levels were measured by finger pulse oximetry. A reference device was designed to align pulse oximeter light-emitting diode, buccal surface of tooth, little finger, lingual surface of tooth and photodiode. Variables were described as means and standard deviation, and the confidence interval was reported. Repeated measures analysis of variance (ANOVA) was used to compare the groups, followed by Bonferroni correction. Student t test for paired samples was used to determine presence of ambient light (α = 0.05). Mean SaO2 level was lower at 4.0 ± 0.2 mm thickness, regardless of presence or absence of ambient light (92.7% and 89.3%). The other thicknesses yielded values of 95.5% and 94.5% at 3.0 ± 0.2 mm, and 96.4% and 96.0% at 2.0 ± 0.2 mm (p < 0.001). There were significant differences between SaO2 values at 4.0 ± 0.2 mm, 3.0 ± 0.2 mm and 2.0 ± 0.2 mm thicknesses, in the presence of ambient light. Mean SaO2 level in positive control was 96.3%, and mean pulse rate was 69.5 bpm in presence of ambient light; in the absence of light, these values were 96% and 70.5 bpm. Enamel and dentin thickness interfere with SaO2, regardless of presence or absence of ambient light. The lowest SaO2 levels were found for the thickest tooth samples.

We describe two partial dentaries of mammals from the Middle Jurassic of Scotland. They belong to the early cladotherian Palaeoxonodon ooliticus. These dentaries comprise the first specimen of P. ooliticus ever found – although its significance was initially unrecognised so it remained undescribed until now – and the most recently discovered specimen, found during fieldwork in 2017. The new specimen preserves part of the coronoid process of the dentary, previously unknown for P. ooliticus, demonstrating the presence of a deep masseteric fossa, with a prominent crest enclosing the fossa anteriorly, and a masseteric foramen, located in the masseteric fossa on the buccal surface of the dentary. On the lingual surface, the mandibular foramen is offset from the Meckel’s sulcus, and positioned below the alveolar plane. These morphologies allow an updated analysis of the phylogenetic position of P. ooliticus, confirming a sister-taxa relationship between Palaeoxonodon and Amphitherium. The position of the mandibular foramen, and the slight extension of the masseteric fossa into the body of the dentary are new autapomorphies for Palaeoxonodon.

The purpose of this study was to examine the efficacy of bone augmentation using the "Casing Method," which enables large-scale osteogenesis, and the feasibility of using the augmented bone in dental implants. Three Beagle dogs were used. After tooth extraction, a polyethylene terephthalate case (20 mm × 5 mm × 10 mm) was placed on the buccal surface of the mandible. A mixture of hydroxyapatite and beta-tricalcium phosphate (volume ratio = 1:1) was infiltrated into a suspension of autologous superfine bone powder and plasma, and the resulting mixture was packed into the case. After 16 weeks, the implant was inserted into the augmented bone and the original bone. Specimens of the mandible were collected at 2, 4, 8, and 16 weeks after implant insertion, and undecalcified sections were prepared. The integration of the implant into the surrounding bone tissue was observed histologically. Favorable bone formation was observed in the regions where bone augmentation was performed. The space between the cut bone surface and the implant was filled with newly formed bone in both the augmented and original bone regions. In addition, there was higher bone density in the augmented bone than that in the original bone at the coronal half of the implant at 16 weeks. As a result, bone-to-implant contact was significantly higher in the augmented bone region than in the original bone region. These results suggest that bone augmentation surgery using the "Casing Method" is an effective technique for expanding the application of dental implants. Anat Rec, 301:892-901, 2018. © 2018 Wiley Periodicals, Inc.

SUMMARY The purpose of this study was to evaluate the chemical bonds of a self-etch 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) adhesive to natural noncarious cervical lesions (NCCLs) and compare them with those occurring in sclerotic dentin in artificially prepared defects (APDs). Four human teeth with natural NCCLs on the buccal surface were selected. Artificial defects matching the natural lesions were prepared on the lingual surface of the same teeth serving as control. Micro-Raman (MR) spectroscopy was used to quantify mineral content in natural NCCLs and in APDs. Fourier transform infrared-photoacoustic spectroscopy (FTIR-PAS) readouts were taken before and after adhesive application to analyze the protein matrix/mineral (M:M) ratio and chemical interactions between 10-MDP adhesive and dentin. The MR and FTIR-PAS spectra collected from natural NCCLs demonstrated a larger area of the band (961 cm−1, PO4) and lower M:M ratio, respectively, characterizing a hypermineralized dentin, compared with APDs. FTIR-PAS demonstrated emergence of a peak (1179 cm−1, P=O) in spectra after adhesive treatment, demonstrating a more intense chemical interaction in natural NCCLs. The results demonstrated that chemical bonding of 10-MDP adhesive to natural NCCLs is more intense, due to the hypermineralized surface, and suggest that it is unnecessary to remove the hypermineralized layer with burs, as this may decrease the chemical bonding potential of 10-MDP.

To evaluate the effects of different hemostatic agents on the shear bond strength (SBS) in vitro and clinical bond failure rate of orthodontic metal brackets in vivo. A total of 100 human premolar teeth were randomly divided into five groups: control, blood, Viscostat, hydrogen peroxide (H2O2), and epinephrine. Teeth were bonded with same light-cured adhesive and composite. After storage in distilled water for 24 h, thermal cycling was used as an aging procedure on all samples. The brackets were subjected to an SBS test at a speed of 0.5 mm/min until bracket debonding. SBS values and the adhesive remnant index were evaluated. Ninety-nine patients (52 female, 47 males) undergoing routine orthodontic treatment were recruited for this controlled clinical study at bonding stages. All patients with bleeding on the buccal surface of any premolar tooth or teeth at bonding were included in this study. Over 6 months, the bond failure rate was calculated. Data were analyzed using one-way analysis of varianc...

The purpose of this chapter is to describe a simplification of the techniques to correct a displaced midline or a collapsed occlusion correction by identifying target teeth to design the biomechanics. I-type C-tube miniplates were placed on the symphysis and the posterior buccal surface of the mandible to provide accurate support against multidirectional forces. C-tube miniplates are short, flexible, useful devices for retracting or pushing the teeth, enabling efficient correction of midline deviations without undesirable side effects. The miniplate is secured with two or three mini-implants, ensuring great stability and simple approaches for complicated malocclusions.

IntroductionEsthetics is one of the common issues because of which patients consult dental orthodontic treatment. Two ways of tooth bleaching are available these days, which includes in-office bleach and home bleach. Various bleaching protocols are available these days for treating the tooth surfaces. Hence, we planned the present study for investigating the impact of various intracoronal bleaching protocols on shear bond strength of ceramic brackets bonded to tooth surface after bleaching.Materials and methodsThe present study included assessment of 100 extracted maxillary central incisors with the integrated buccal surface. A resin block was made and individual teeth were embedded in each block. Root canal therapy procedure was performed in all the teeth, after which 2 mm short of tooth apex up to the level of cementoenamel junction, removal of the root canal filling was done. All the samples were broadly divided into four study groups with 25 samples in each group. Bleaching procedure was carried in all the samples intracoronally followed by testing of shear bond strength using universal force testing machine. Following the modified adhesive remnant index (AI), assessment of remaining adhesive on the brackets was done. All the results were compiled and analyzed by Statistical Package for the Social Sciences (SPSS) software version 17.0.ResultsIn the control group, mean shear bond strength was found to be 17.9 MPa. While comparing the carbamide peroxide (CP) group with sodium perborate study group, we observed a statistically significant difference. Nonsignificant results were obtained while comparing the shear bond strength in between sodium perborate group and hydrogen peroxide (HP) group.ConclusionIntracoronal bleaching does affect the shear bond strength of ceramic brackets. Sodium perborate bleaching influences shear bond strength more strongly than other bleaching agents such as CP and HP.Clinical significanceIn patients undergoing orthodontic treatment, HP is a preferred agent where bleaching has to be followed by orthodontic bonding to the tooth surface.How to cite this articleIska D, Devanna R, Singh M, Chitumalla R, Balasubramanian SCB, Goutam M.In vitroAssessment of Influence of Various Bleaching Protocols on the Strength of Ceramic Orthodontic Brackets bonded to Bleached Tooth Surface: A Comparative Study. J Contemp Dent Pract 2017;18(12): 1181-1184.

Statement of the problem: Enormous tooth substance is removed to receive all ceramic restorations which in turn affects the vitality of the tooth. Purpose of the Study: The purpose of this study is to measure the remaining dentin thichness (RDT) following tooth reduction for all ceramic crowns in freshly extracted premolars and to correlate RDT to Pulpal response. Materials and Methods: 45 freshly extracted human permanent maxillary first premolar teeth, scheduled to be removed for orthodontic purpose were selected from patients ranging from 16 to 30 years of age. The Samples were grouped by Three axial surfaces (Mesio Buccal (MB),Buccal (B) and and Disto-Buccal (DB) Axial Surfaces) , Three Age Groups (G1- 15 to 20, G2 – 21 to 25 , and G3 – 26 to 30) and finally by sex . Tooth preparation was done following standard guidelines for metal free restorations ( 1.2mm radial shoulder and as minimal taper clinically possible) by a single operator. RDT was measured in the three axial surfaces (Buccal, Mesio Buccal and Disto Buccal ) using a Stereomicroscope and Image Analysis Software. The results were statistically analyzed using f – test ( one way anova). Among the three surfaces Disto buccal showed the least RDT least RDT ( 0.97mm) followed by mesio-buccal (1.55mm) and buccal surface( 2.11mm). P

The mandibular canal contributes to the development and growth of the mandible, as it acts as a conduit for the growing inferior alveolar neurovascular structures. A clear understanding of the canal’s pathway is, therefore, important in interpreting the growth pattern of the inferior alveolar neurovascular bundle. This study investigated the position of the mandibular canal within the body of the mandible and its general dimensions within a pediatric collection of mandibles. The sample included 45 mandibles and was subdivided into three: group 1 (30 gestational weeks to birth), group 2 (birth to 12 months), and group 3 (1 to 4 years). Mandibles were scanned using a Nikon XTH 225L micro-CT unit. Scanning conditions ranged between 85 kV/83 µA and 100 kV/100 µA. Measurements included: the maximum width and height of the mandibular canal and distances between the mandibular canal and the relevant surfaces of the mandible. Data analysis included an ANOVA, MANOVA, and principal component analysis. The mandibular canal increased significantly in size from 30 gestational weeks to 12 months relative to the deciduous molar crypts. Postnatally, the mandibular canal increased significantly in height at the level of the second deciduous molar crypt. The canal lies closer to the buccal surface in the region of the first and second deciduous molar teeth. The consistency in the positioning of the mandibular canal within the body of the mandible may assist in predicting the occurrence of aberrant growth patterns, particularly during the initial stages of growth.

We describe the upper portion of the bill sheath (rhinotheca) of the kākāpō (Strigops habroptilus) from three adult female specimens. The external buccal surface of the rhinotheca is deeply concave with a prominent palatal stop and hardened chevrons creating a ‘milling apparatus’ that the kākāpō uses to grind food. The palatal stop presents a working face of 40–50 mm2. The internal surface of the rhinotheca mirrors the overlying premaxilla and provides a distinct thickened abutment consistent with resistance against the increased workload of the mandibles (gnathotheca) due to the kākāpō’s fibrous diet and chewing style. Along the midline, the rhinotheca at the abutment is up to 5.6 mm thick, compared with as thin as 2.1 mm elsewhere on the midline. The closely related Nestor parrots have less developed palatal stops, chevrons and abutments on their rhinothecas consistent with their lower preference for fibrous plant material. The form of the rhinotheca agrees with the kākāpō’s feeding ecology as a...

Objectives: This reseach aimed to describe micrograph images of experimental carious lesions at early stage. Method: Experimental study. 60 permanent extracted premolars (patient aged 18-25) were cleaned and removed remaining soft tissue. Each tooth was painted with acid-resistant coating leaving an enamel window of approximately 1 × 1 mm2 in buccal surface. After 96 hours being soaked in demineralization solution to create artificial carious lesion, the coating was removed, and all teeth would be evaluated using ICDAS criteria and made tooth specimens to be observed under a scanning electronic microscope (SEM). Results: After being soaked in demineralization solution, the carious lesion gained was at stage ICDAS 1 with 66.7% ; and 33.3% at stage 2. Mean depth and area of the lesions was 107.6 µm and 1.14 µm2, respectively. The difference in depth and area of lesions between group ICDAS 1 và ICDAS 2 was significantly statistical with p=0.0001. Micrograph images showed that after being soaked in demineralization solution, enamel surface became rough, enamel rods lost minerals in the body more than in the sheath, cross-sectional images showed widened gaps between the rods due to demineralization. There was a difference in demineralization degree between group ICDAS 1 and 2. Conclusion: Image of cariouslesions gained after being soaked in demineralization solution showed that naturally carious and artificially carious-like lesions shared many similar characteristics due to theevaluation based on ICDAS criteria for detecting early carious lesions and scanning electronic microscope. DOI: 10.14693/jdi.v23i1.973

Introduction Aim of this in vitro study is to evaluate the loss of tooth enamel after acid etching using a custom made profile projector (×100). Materials and Methods Twenty human extracted maxillary and mandibular premolars were collected, and each tooth was mounted on an acrylic block (2 cm × 1 cm) along with a 0.8 mm stainless steel wire partially embedded in acrylic in front of the buccal surface of the teeth. The 0.8 mm wire was used for reference; the image appeared on the projection screen was 80 mm implying that magnification ×100 has been achieved. Fabrication of custom made profile projector followed the principles of optics. Two projections of each sample before and after etching were projected. The projection was recorded using tracing paper. The difference between the two tracings before and after etching was measured using a millimeter scale. This reading was converted into microns, i.e., 1 mm = 10 μ. Results The statistical method used for this study is a measure of central tendency. The research shows that the average enamel loss was around 15.25 microns. The median is a value at the midpoint of the group, and median for enamel loss is 15 μ Mode for enamel loss is 15 μ that means most frequent or most repetitive enamel loss is 15 μ. The maximum enamel loss was 25 μ, and minimum of that was 10 μ. Conclusions The results of this study indicate that etching enamel with 37% phosphoric acid for 30 s loses 15 μ of surface enamel using an economical and efficient custom made profile projector.

Objective This study investigated the surface roughness of enamel after debonding and instrumentation with commonly used methods. Methods Part I: a survey was sent to active members of the American Association of Orthodontists to determine popular bonding, debonding, and polishing protocols. Part II: brackets were bonded to the buccal surface of 30 extracted human premolar teeth. After debonding, residual adhesive was removed with 12-, 16-, and 20-fluted titanium carbide burs as based upon the survey results. The teeth were scanned with a surface profilometer for surface roughness. Part III: the teeth were further polished using a Reliance Renew polishing point or a prophy cup with pumice and rescanned for surface roughness. Results Part I: the majority of respondents used a generic bracket-removing plier to remove fixed appliances (53%) and a high-speed handpiece for adhesive removal (85%). The most popular bur was a 12-fluted carbide bur without water spray. The majority of respondents used pumice paste and/or Reliance Renew points after adhesive removal. Part II: there was a significant difference in enamel surface roughness when 12-, 16-, and 20-fluted carbide burs were compared via surface profilometry. Part III: further polishing with a Reliance Renew point or a prophy cup and pumice did not provide a significantly smoother surface. Conclusions The results show large variation in debonding and polishing techniques. Creating a smooth enamel surface is equally possible with 12- or 20-fluted carbide burs. Further polishing with pumice and prophy cup or Renew point does not provide an enamel smoother surface.

The objective of the case study is for the treatment of deviated and rotated teeth by ISW (Improved Super-elastic Ti-Ni alloy wire, developed by Tokyo Medical and Dental University). An adult female (37 years old) came to our clinic with a chief complaint of abnormal tooth axis of lower arch combined with spacing and rotation of other teeth. This patient mentioned she didn’t care about the problem of facial asymmetry. By using ISW, lower deviated teeth were corrected rapidly. Rotation of lower left and right premolars were corrected simply by ISW leveling. For correction of rotated upper left second premolar, we placed a bracket on the mesial surface of #25 temporarily and Ni-Ti open coil-spring was placed in between #25 and #26 in order to increase inter-bracket span so as to create space for bracket bonding on the buccal surface. ISW was fully engaged into #25 and then rotation was corrected by further leveling. After 18 months of active treatment, a stable occlusion and a desirable esthetic outcome was achieved and the patient was pleased with the treatment result after the active treatment.

Purpose The study evaluated and compared the effect of pre-etching heat treatment and post-etching surface neutralization on the surface texture parameters and initial adhesion strength of orthodontic brackets bonded to lithium disilicate glass-ceramic using water-based and resin-based cement. Materials and methods A total of 120 samples were fabricated by duplicating the buccal surface of the maxillary premolar. The samples were randomly assigned to two groups: the cementing surface of group 1 samples was heat-treated, and that of group 2 samples was left untreated. The samples of each group were further divided into 4 subgroups (n = 15) according to the use of neutralization and the type of cement used for bonding. The surface texture parameters after etching were determined using a non-contact surface profilometer, and the bond strength was determined by a universal material tester. The results were analyzed by analysis of variance and the Scheffe post hoc test. Results The samples that were heat-treated showed statistically significant higher bond strength in all the subgroups, and the acid-neutralized samples showed higher bond strength using both types of cement; however, the increase was statistically significant only in resin-based cement-bonded samples. Resin-based cement-bonded samples showed higher bond strength than water-based cement-bonded samples. Conclusion Pre-etching heat treatment and post-etching acid neutralization of the cementing surface of lithium disilicate glass-ceramic significantly improve the surface texture and initial bond strength to orthodontic brackets.

This study evaluated the effects of tooth bleaching with high-concentration of hydrogen peroxide on alterations of translucency parameter (TP) and color of dentin and enamel. The crown of five human molars was sectioned into four slices parallel to buccal surface. The dentin of external slices containing buccal/ lingual enamel was fully removed with diamond bur; while these slices were used to assess alterations on enamel. Alterations on dentin were assessed into the center of internal slices. The color of specimens was measured over white and black backgrounds using a spectrophotometer (CieL*a*b) at baseline, allowing to calculate the TP by difference between the color measured over each background. Specimens were submitted to three 15-min applications of 35% hydrogen peroxide followed by their storage in water for one-week. Afterwards, the color measurements were repeated at both backgrounds. Color (∆L, ∆a, ∆b and ∆E) and translucency (∆TP) changes were calculated and data individually analyzed by T-test (α = 0.05). Influence of hard tissue and assessment time on each color parameter was also analyzed by 2-way repeated measure ANOVA (α = 0.05). Tooth bleaching resulted in increased lightness for the enamel, whereas no alteration on this parameter occurred for dentin. No difference between the tooth hard tissues was observed regards the other color parameters and ∆E. A slightly reduction on TP was observed only for the enamel. In conclusion, 35% hydrogen peroxide caused similar color and translucency changes on dentin and enamel. Resumo Este estudo avaliou os efeitos do clareamento dental com peróxido de hidrogênio em alta concentração nas alterações do parâmetro de translucidez (PT) e cor da dentina e esmalte. A coroa de cinco molares humanos foi seccionada em quatro fatias paralelas à superfície vestibular. A dentina das fatias externas contendo esmalte vestibular/ lingual foi totalmente removida com ponta diamantada, sendo estas fatias usadas para verificar as alterações no esmalte. Alterações na dentina foram verificadas no centro das fatias internas. A cor das amostras foi mensurada sobre fundos preto e branco usando um espectrofotômetro (CieL*a*b) no início, permitindo calcular o PT pela diferença de cor medida sobre cada fundo. As amostras foram submetidas a três aplicações de 15 minutos de peróxido de hidrogênio a 35% seguido pelo seu armazenamento em água por uma semana. Após isto, as mensurações de cor foram repetidas em ambos os fundos. Mudanças de cor (∆L, ∆a, ∆b e ∆E) e translucidez (∆PT) foram calculadas e os dados analisados pelo Teste T (α = 0,05). A influência do tecido duro e do momento de avaliação em cada parâmetro de cor foi também analisado através de ANOVA de duas vias para medidas repetidas (α = 0,05). O clareamento dental resultou em maior luminosidade (∆L) para o esmalte, enquanto que nenhuma alteração neste parâmetro ocorreu para a dentina. Nenhuma diferença entre os tecidos duros dentais foi observada em relação aos outros parâmetros de cor e ∆E. Uma leve redução na PT foi observada apenas para o esmalte. Como conclusão, peróxido de hidrogênio a 35% causou similar alteração de cor e translucidez no esmalte e na dentina.

The present study was conducted to evaluate the microleakage and microshear bond strength of different types of dental composite. For microleakage test, 45 caries-free human permanent maxillary molars with no crack, decay, or structural deformities were collected. A standard Class V cavity was prepared on the buccal surface of each tooth. The cavity of each tooth was acid etched and the adhesive material was applied to the etched surface, gently dried and cured. The prepared teeth were divided randomly into three groups, (15 for each group) according to the types of composite. Group A: Tetric EvoCeram nanohybrid composite (Ivoclar vivadent Inc. USA and Canada), Group B: Tetric EvoCeram Bulk fill composite (Ivoclar vivadent Inc. USA and Canada) and Group C: Sonic Fill Bulk fill composite (Kerr Restoratives, USA). The specimens in each group were restored with the corresponding composite and cured according to manufacturer’s instructions. The specimens were submitted to thermo-cycling, covered with nail varnish, followed by immersion in dye solution. Each tooth was sectioned longitudinally using hard tissue microtome. The microleakage was measured using digital microscope at ×10 magnification. The dye penetration in the specimens was evaluated for both the occlusal and gingival surfaces based on a scoring system. Kruskal-Wallis test was used to determine the difference between microleakage scores in the three study groups at a 0.05 level of significance. For microshear bond strength test 30 caries-free human permanent mandibular molars with no crack, decay, or structural deformities were collected. The occlusal surface of the teeth were ground perpendicular to the long axis of each tooth to expose a flat dentin surface. A dentine slice with thickness 2 mm was sectioned perpendicular to the long axis of each tooth. The surfaces of dentin slides were acid etched and the adhesive material was applied to the etched surface, gently dried and cured. The specimens were divided into three main groups (10 for each group) according to the type of composite resins used as in microleakage test. Composite resins was placed, cured and the specimens were submitted to thermocycling before testing. The recorded values of bond strengths in (MPa) were collected, tabulated and statistically analyzed. One way analysis of variance (ANOVA) and Tukey’s tests were used for testing the significance between the means of tested groups. The results showed that Tetric EvoCeram nanohybrid composite had the highest scores of microleakage followed by Tetric EvoCeram Bulk fill and Sonic Fill Bulk fill which showed the lowest scores. The results also showed that Sonic Fill Bulk fill composite had the highest microshear bond strength value followed by Tetric EvoCeram Bulk fill and Tetric EvoCeram nanohybrid composite which showed the lowest value.

Objective To characterize bone height and buccal cortical bone thickness of the caudal mandible of healthy dogs. Study Design Prospective original study. Sample Population Client-owned dogs (n = 36). Methods Dogs were distributed by weight into 3 groups ( 20 kg). Thirteen transverse plane computed tomography images were selected for each dog based on anatomic landmarks from the 4th premolar (PM4) through the 2nd molar. On each image, bone thickness was measured along the buccal surface of both mandibles from the alveolar margin to the ventral border in 3 mm increments. The number of 3 mm increments were recorded as an estimation of mandibular height. Results Buccal bone was generally thicker ventrally in the area studied with decreasing bone thickness over both roots of PM4 and the mesial root of the 1st molar (M1). Cortical bone thickness of 10 kg compared with the number of observations at the immediately mesial and distal locations. Conclusion Thin cortical bone overlying the mesial and distal roots of PM4 and the mesial root of M1 limits use of these areas for application of monocortical anchorage devices. Decreased mandibular bone height at mandibular M1 may create a stress riser at this location, which along with thin cortical bone may explain why this is a common area for mandibular fracture.

Background: Ultrasonic scaling has been used commonly for stain and calculus removal in dental clinic for over 60years. Previous researches even had proved that ultrasonic scaling may give effects on the surface of tooth root. Ultrasonic wave exposure for 20 seconds or more can increase caspase-3 activity as an indicator of increased apoptotic cells associated with tissue damage. Purpose: This research was aimed to investigate the effects of ultrasonic scaling duration and replication on caspace-3 expression in dental pulp cells. Methods: The samples of this research were 54 male Sprague Dawley rats aged 2 months old divided into 2 groups, each of which consisted of 27 mice. The first group was induced with stain, while the second group was not. Each group was divided into 3 subgroups for ultrasonic scaling 1, 3, and 5 times. Each subgroup was divided into 3 sub-subgroups for duration procedure of 15, 30 and 60 seconds respectively. During scaling process, those rats were anesthetized using 0.1 ml of ketamine and 0.1 ml of xylol added to 2 ml of distilled water injected intramuscularly into their right thigh as much as 0.4 ml. Scaling was done on buccal surface of right first maxillary molar from cervical to occlusal. The teeth were decalcified and embedded in paraffin, then their sagittal plane was cut for thickness of 3µm and painted with immunohystochemistry for detecting caspace-3 expression of cell within dental pulp. Results: The results showed that the duration and replication of ultrasonic scaling procedures affected on the expression of caspace-3 cells as analyzed with Univariate Analisis of Variance test (pConclusion: It can be concluded that duration and replication of ultrasonic scaling procedure on teeth with and without stain enhauced the expression of caspace-3 in dental pulp cells.

BACKGROUND AND OBJECTIVES Impaired bone formation of the buccal alveolar plate after tooth extraction during adolescence increases the difficulty of future implant restoration. This study was undertaken to assess the feasibility and efficacy of transplanting autogenous scaffold-free culture-expanded mesenchymal stem cell (MSC) sheets to the buccal alveolar bone surface to stimulate local bone growth. MATERIAL AND METHODS Mandibular bone marrow was aspirated from 3-month-old pigs (n = 5), from which MSCs were isolated and culture expanded. Triple-layer MSC sheets were then fabricated using temperature-responsive tissue culture plates. One month after bone marrow aspirations, the same pigs underwent bilateral extraction of mandibular primary molars, immediately followed by transplantation of 3 autogenous triple-layer MSC sheets on to the subperiosteal buccal alveolar surface of 1 randomly chosen side. The contralateral side (control) underwent the same periosteal reflection surgery without receiving MSC sheet transplantation. Six weeks later, the animals were killed and specimens from both sides were immediately harvested for radiographic and histological analysis. Buccal alveolar bone thickness, tissue mineral density (TMD), mineral apposition and bone volume fraction (BV/TV) were quantified and compared between the MSC sheet and control sides using paired t-tests. RESULTS Triple-layer MSC sheets were reliably fabricated and the majority of cells remained vital before transplantation. The thickness of buccal bone tended to increase with MSC sheet transplantation (P = .18), with 4 of 5 animals showing an average of 1.82 ± 0.73 mm thicker bone on the MSC sheet side than the control side. After being normalized by the TMD of intracortical bone, the TMD of surface cortical bone was 0.5-fold higher on the MSC sheet side than the control side (P

This study aims to demonstrate that harmful stimulation of the buccal mucosa because of a rough tooth surface may cause lumbago. This report illustrates two cases of women in their 30s and 40s who are suffering from lumbago due to unknown causes. The patients are cured by a simple dental procedure in which the buccal surface of a molar is smoothened, thereby inhibiting the negative stimulation of the buccal mucosa. Soon after this treatment, the symptoms of lumbago have subsided. The reason for the effectiveness of this treatment remains unclear. However, the balance dysregulation observed in the patient may have been due to stimulation of the oral mucous membrane by the rough surface of the tooth. It is important for dentists to pay attention to the effects of tooth formation, dental restorations, and dental prosthetics on the entire body. A dental condition may have an effect on diseases affecting other parts of the body; thus a dental treatment may be considered as an option for the management of other systemic disorders. It appears that cooperation between the fields of dentistry and medicine is of utmost importance.

El diagnóstico ortodóncico requiere un examen minucioso de los tejidos de soporte periodontal; alteraciones como dehiscencias, fenestraciones y otros defectos óseos deberían ser incluidos tanto dentro del diagnóstico como dentro del plan de tratamiento.El propósito de este estudio fue investigar la prevalencia y distribución de defectos óseos en un grupo de potenciales pacientes ortodóncicos no tratados, utilizando Tomografías Computarizadas Cone Beam (TCCB), con el objetivo de evaluar su posible incorporación a los estudios diagnósticos básicos previos al tratamiento ortodóncico.Se analizaron 33 TCCB y un total de 792 dientes en busca de dehiscencias y fenestraciones y posteriormente se midió el grosor del hueso alveolar vestibular y palatino o lingual en el tercio medio radicular de 528 dientes. Los datos obtenidos fueron utilizados para realizar un análisis estadístico descriptivo e inferencial que arrojó los siguientes resultados: un 36% de la muestra presentó algún tipo de defectos óseos; las dehiscencias fueron más comunes que las fenestraciones y fueron más comunes en la arcada inferior, mientras que las fenestraciones lo fueron en la superior; la cortical más gruesa se encontró en la superficie lingual de molares inferiores y la más delgada en la superficie vestibular de caninos inferiores.Las TCCB poseen el potencial de reemplazar las radiografías convencionales y permitir realizar decisiones diagnósticas acertadas en base a la arquitectura ósea de cada paciente, por lo que se recomienda su uso como auxiliar diagnóstico, especialmente en pacientes de alto riesgo.

Summary: This paper is a casereport description of the paramolar tubercle presence on the buccal surface of left upper secondpremolar (25 tooth). The description was done under the dental anthropology point of view and thistooth mark may be useful to classify and identify human populations. Key words: Dental anthropology.Dental morphology. Non-metric dental crown traits. Paramolar tubercle.

This study investigated the softening and erosive effects of various paediatric over-the-counter (OTC) oral liquids on deciduous teeth. Twenty sectioned and polished deciduous enamel blocks were ground on the buccal surface (2 × 2 mm2) and randomly divided into five groups, immersed into four commercially-available paediatric OTC oral liquids (two for paracetamol, both sugared; and two for chlorpheniramine, one sugared and one sugar-free), with deionized water as control. The pH of the oral liquids ranged from 2.50 to 5.77. Each block was immersed into the test or control groups for 15 s, rinsed with deionized water, and Vickers micro-hardness (n = 5) was measured. After twenty cycles of immersion and hardness measurements, Scanning Electron Microscope (SEM) and Energy Dispersive X-ray Spectrometry (EDS) were used to evaluate the surface morphology and chemistry of the tooth blocks, respectively. The pH values of the liquids were also recorded. Rapidly descending trends in the micro-hardness ratios of the four test groups were observed that were statistically different from the control group (p < 0.001). EDS showed an increase of Ca/C ratio after drug immersion, whereas SEM showed an enamel loss in all the test groups. Paediatric OTC oral liquids could significantly soften the enamel and render them more susceptible to caries, such that the formulation of the oral liquids is the major factor.

Aims: This study aims to evaluate the bond strength (BS) and microleakage (ML) of the newer bonding agents to enamel and dentin. Objective: (1) To analyze the BS between self-etch and total-etch adhesives. (2) To analyze the depth of ML between self-etch and total-etch adhesives. Materials and Methods: Sixty mandibular premolars were fabricated and randomly divided into three groups: Group I (n = 20)-bonded with self-etch adhesive + nanohybrid, Group II (n = 20) with total-etch adhesive + micro hybrid and Group III (n = 20) with total-etch adhesive + nanocomposite. Teflon ring molds were used to make composite resin cylinders bonded to the buccal surface. Class II box cavity was prepared on the samples' proximal surface and condensed with composite resin with each group's specific bonding protocol. Shear BS and ML testing were conducted, and data analyzed. Statistical Analysis: Kruskal–Wallis analysis was done to statistically differentiate the BS and ML between the three experimental groups; the P < 0.05, it showed a statistically significant difference. Intergroup comparison was made using the Mann–Whitney U test. Conclusions: Within this study's limitation, resin bonded with self-etch G-Premio Bond used in selective etch technique showed the highest BS and resistance to ML.

SUMMARY This study examined the effect of both the tooth substance and restorative filling materials on the increase in pulp chamber temperature when using light-curing units with different power densities. The tip of a temperature sensor was positioned on the pulpal dentinal wall of the buccal side of a maxillary premolar. Metal tubes were inserted in the palatal and buccal root of the tooth, one for water inflow and the other for water outflow. Polyethylene tubes were connected from the metal tubes to a pump to control the flow rate. For the unprepared tooth group (group 1), the tooth was light-cured from the buccal side using two light-curing units (three curing modes): the VIP Junior (QTH, BISCO, Schaumburg, IL, USA) and the Bluephase LED light-curing units (two modes: LEDlow and LEDhigh; Ivoclar Vivadent, Schaan, Liechtenstein). The power densities of each light-curing unit for the LEDlow, QTH, and LEDhigh modes were 785 mW/cm2, 891 mW/cm2, and 1447 mW/cm2, respectively. All light-curing units were activated for 60 seconds. For the prepared tooth group (group 2), a Class V cavity, 4.0 mm in width by 4.0 mm in height by 1.8 mm in depth in size, was prepared on the buccal surface of the same tooth for the temperature measurement. The light-curing and temperature measurements were performed using the same methods used in group 1. The cavity prepared in group 2 was filled with a resin composite (Tetric N Ceram A3 shade, Ivoclar Vivadent) (group 3) or a flowable composite (Tetric N Flow with A3 shade, Ivoclar Vivadent) (group 4). The light-curing and temperature measurements were performed for these groups using the same methods used for the other groups. The highest intrapulpal temperature (TMAX) was measured, and a comparison was conducted between the groups using two-way analysis of variance with a post hoc Tukey test at the 95% confidence level. The TMAX values were as follows: 38.4°C (group 1), 39.0°C (group 2), 39.8°C (group 3), and 40.3°C (group 4) for the LEDlow mode. For the QTH mode, the TMAX values were 40.1°C (group 1), 40.4°C (group 2), 40.9°C (group 3), and 41.4°C (group 4). For the LEDhigh mode, the TMAX values were 43.3°C (group 1), 44.5°C (group 2), 44.7°C (group 3), and 45.3°C (group 4). The statistical analysis revealed the following: the TMAX values were arranged by mode in the following manner: LEDlow < QTH < LEDhigh (p

The mucosal pellicle is defined as the protein film adsorbed onto oral mucosa. This study aimed at characterizing the ultrastructure of human epithelial buccal cells and localizing salivary mucins MUC5B, a major constituent of the mucosal pellicle. Cells were sampled from the buccal surface and prepared for Transmission Electron Microscopy using high-pressure freezing/cryosubstitution followed by immunogold labelling of MUC5B. Morphologically, cells were visualized as typical cells of the superficial layer of a squamous nonkeratinized epithelium with a partly degraded plasma membrane. The outer surface of the plasma membrane was lined with a biological material of medium electron density. MUC5B were detected in the extracellular space, and particularly in the vicinity of the plasma membrane, sometimes onto fibrils protruding from the membrane. This area was, therefore, considered as constituting the mucosal pellicle, which appeared as a mixed film of both salivary and epithelial components. The distribution of gold particles suggested that the surface of the pellicle was not uniform, and that the film thickness could reach up to 100 nm. This work showed the feasibility of visualizing and characterizing the mucosal pellicle directly on human epithelial buccal cells sampled in a noninvasive manner.

Background and aim. Orthodontic tooth movement (OTM) is a process whereby the application of a force induces bone resorption on the pressure side and bone apposition on the tension side of the lamina dura. However, only limited data are available on the in vivo behavior of the periodontal tissues. The aim of this study was to assess the changes of periodontal tissues, induced by the orthodontic canine retraction, using 40 MHz ultrasonography.Methods. Ultrasonographic evaluation of periodontal tissues was conducted in 5 patients with indication for orthodontic treatment. The upper first premolars were extracted bilaterally due to severe crowding, and the canines were distalized using elastomeric chain with a net force of 100 cN. Ultrasonographic scans (US scans) were performed before, during and after retraction, in three distinct areas of the canines buccal surface: mesial, middle and distal. The reference point was the bracket, which appeared hyperechoic on the US scan. Four different dimensions were obtained: D1 (depth of the sulcus), D2 (thickness of the gingiva), D3 (length of the supracrestal fibers), D4 (width of periodontal space).Results. An increase of D1 was observed in all three areas of the periodontium, during orthodontic treatment. D3 was strongly correlated before and immediately after force delivery only for the mesial area (r=0.828, p

Objective: This study evaluated alveolar bone loss around mandibular incisors, induced by the Herbst appliance. Methods: The sample consisted of 23 patients (11 men, 12 women; mean age of 15.76 ± 1.75 years), Class II, Division 1 malocclusion, treated with the Herbst appliance. CBCT scans were obtained before treatment (T0) and after Herbst treatment (T1). Vertical alveolar bone level and alveolar bone thickness of mandibular incisors were assessed. Buccal (B), lingual (L) and total (T) bone thicknesses were assessed at crestal (1), midroot (2) and apical (3) levels of mandibular incisors. Student's t-test and Wilcoxon t-test were used to compare dependent samples in parametric and nonparametric cases, respectively. Pearson's and Spearman's rank correlation analyses were performed to determine the relationship of changes in alveolar bone thickness. Results were considered at a significance level of 5%. Results: Mandibular incisors showed no statistical significance for vertical alveolar bone level. Alveolar bone thickness of mandibular incisors significantly reduced after treatment at B1, B2, B3, T1 and significantly increased at L2. The magnitude of the statistically significant changes was less than 0.2 mm. The changes in alveolar bone thickness showed no statistical significance with incisor inclination degree. Conclusions: CBCT scans showed an association between the Herbst appliance and alveolar bone loss on the buccal surface of mandibular incisors; however, without clinical significance. RESUMO Introdução: este estudo avaliou a perda óssea alveolar ao redor dos incisivos inferiores induzida pelo aparelho de Herbst. Métodos: a amostra foi composta por 23 pacientes (11 homens e 12 mulheres; média de idade 15,76 ± 1,75 anos), má oclusão de Classe II, divisão 1, tratados com aparelho de Herbst. TCFCs foram realizadas antes do tratamento (T0) e após o tratamento (T1) com o Herbst. A altura e a espessura óssea alveolar dos incisivos inferiores foram avaliadas. As espessuras ósseas vestibular (V), lingual (L) e total (T) foram mensuradas nos terços cervical (1), médio (2) e apical (3) dos incisivos inferiores. O teste t de Student e o teste t de Wilcoxon compararam as amostras dependentes nos casos paramétricos e não paramétricos, respectivamente. As análises de Pearson e Spearman determinaram a correlação entre as alterações na espessura do osso alveolar. Os resultados foram considerados para um nível de significância de 5%. Resultados: os incisivos inferiores não apresentaram significância estatística para a altura óssea alveolar. Após o tratamento, a espessura óssea alveolar dos incisivos inferiores reduziu-se significativamente em V1, V2, V3 e T1 e aumentou significativamente em L2. A quantidade da alteração óssea significativa foi menor que 0,2mm. As alterações na espessura óssea alveolar não apresentam correlação estatisticamente significativa com o grau de inclinação do incisivo. Conclusões: as imagens de TCFC demonstram associação entre o uso do aparelho de Herbst e a perda óssea alveolar no lado vestibular dos incisivos inferiores; entretanto, sem significância clínica.

Purpose: The purpose of this study was to investigate the stress distribution of the surrounding tissues according to 3 proximal plate types of the RPI clasp. Methods: The removeable partial denture which mandibular right and left second premolars and mandibular molars were lost was attached to a three dimensional photo elastic epoxy resin model. Then 120N of vertical load was applied. After 3-dimensional photoelastic stress analysis was used to record the isochromatic fringe patterns. Results: Kratochvil type guiding plane exhibited little uniform stress distribution on load center and alveolar ridge, but higher stress concentration on buccal surface of second premolar. Krol type guiding plane exhibited the stress concentration on the front of load center and relatively higher stress concentration on buccal surface of first premolar. However, this type had no effect on canine. Researcher type guiding plane showed the stress concentration on second premolar and molar, but the little stress distribution on first premolar. Conclusion: In all types, excessive stress concentration was appeared and three types were not significant different.

Background: Sodium hypochlorite solutions have been evaluated for their effects in bonding procedures as they are found to deplete or remove the organic portion of the dentin, particularly the collagen fibrils. The aim of this in vitro study was to assess and compare the efficacies of 1%, 2.5%, 5% and 10% NaOCl at 30, 60 and 120s on etched primary dentin. Methods: 84 primary anterior teeth were ground to expose a flat dentin area on the buccal surface. The specimens were divided into fourteen groups of six each based on the dentin surface treatment (35% phosphoric acid etching for 7 seconds-AE and/or NaOCl application), NaOCl solution concentrations (1%, 2.5%, 5% and 10%) and time of application (0, 30, 60 and 120s). Specimens were prepared for SEM and photomicrographs were taken of the surface and were scored against a five point scale, based on the smear layer and amount of collagen removed. The scores were submitted to Kruskal-Wallis and Mann Whitney tests. Results: This study showed the presence of smear layer in the control group. The group treated with Acid Etchant showed a demineralized pattern of dentin with exposure of dentin tubules and collagen fibrils network on the intertubular and peritubular dentin which was not significantly different from the groups treated with 1% and 2.5% NaOCl. Groups treated with 5% NaOCl were not statistically different from each other, the surface was corroded but collagen fibrils were not completely depleted. Groups treated with 10% NaOCl were not statistically different from each other and showed complete removal of collagen fibrils with wider tubular apertures and several secondary tubules on peritubular and intertubular dentin. Conclusion: Higher concentrations of NaOCl solutions (5% and 10%) produced significant changes in the etched primary dentin. The higher the concentration of the NaOCl solution, the lower can be the time for the application of the solution for the complete removal of collagen fibrils.