Search

This article investigated the effects of airborne-particle abrasion and nanosilica (nano-Si) infiltration treatment on the surface characteristics of dental zirconia. A total of 15 unsintered zirconia ceramic green bodies (10 × 10 × 3 mm) were divided into three groups (n = 5): Group C, no treatment after sintering; Group S, airborne-particle abrasion with 50-µm aluminum oxide particles after sintering; and Group N, infiltration of nano-Si followed by sintering and hydrofluoric acid (HF) etching. The zirconia disks' surface roughness was analyzed by atomic force microscopy (AFM). The surface morphology of the specimens was analyzed using scanning electron microscopy (SEM), and the chemical composition was analyzed by energy-dispersive x-ray (EDX). Data were statistically analyzed by Kruskal-Wallis test (P < .05). Zirconia surface treatments by infiltration of nano-Si, sintering, and HF etching showed multiple changes in the surface features. The surface roughness of Groups C, S, and N were 0.88 ± 0.07 µm, 1.26 ± 0.10 µm, and 1.69 ± 0.15 µm, respectively. The surface roughness of Group N was significantly higher than that of Groups C and S (P < .05). EDX analysis showed peaks that corresponded to silica (Si) after infiltration with colloidal Si that disappeared following acid etching. Infiltrating nano-Si increases the surface roughness of zirconia. The formation of retentive nanopores on the surface potentially improves the zirconia-resin cement bonding strengths. [ABSTRACT FROM AUTHOR]

Following implant placement, a soft tissue barrier will form at the healing abutment connection called peri-implant mucosa. The dimension of this anatomical structure seems to play a key role in maintaining long-term peri-implant and marginal bone level stability. In its early stages, soft tissue healing is a process involving many cellular and molecular events. Enamel matrix derivative (EMD) may improve and accelerate soft tissue wound healing and inflammatory resolution. In the present split-mouth randomized clinical trial, EMD was used to influence the early phase of soft tissue healing around dental implants placed with a single-stage approach into a completely healed ridge. A total of 60 implants were placed in 30 patients (2 implants per patient, one in the test group and one in the control group). In the test sites, EMD was administered around the healing abutment before soft tissues were sutured. Soft tissue healing index (HI) and secondary endpoints (clinical, radiographic, and patientreported outcomes) were measured. Better outcomes were recorded in patients receiving EMD for all parameters. The present results support the use of EMD to improve and accelerate soft tissue wound healing around implants. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinical and radiographic results of simultaneous implant placement using transcrestal sinus floor elevation (TSFE) with and without enamel matrix derivative (EMD) application. Materials and Methods: Twenty-four patients were randomly assigned into two groups: The EMD+TSFE group (n = 13 patients, 20 implants) received TSFE with EMD application, and the TSFE group (n = 11 patients, 20 implants) received TSFE without EMD application. The patients were recalled at 3 (T3) and 12 (T12) months postsurgery. The residual bone height (RBH), implant protrusion length (IPL), peri-implant sinus bone level (SBL), endo-sinus bone gain (ESBG), and implant stability (ISQ) were measured. Multivariate regressions were performed for the groups. Results: At T3, the ESBG was 3.72 ± 0.85 mm in the EMD+TSFE group and 3.10 ± 0.05 mm in the TSFE group, and there were statistically significant differences (P < .05). However, there were no statistically significant differences in ESBG at T12 between the groups (P > .05). ISQ values did not show a statistical difference between the groups at T1 and T3, but at T3 in the TSFE+EMD group, there was a statistical increase in the intragroup evaluation compared to the TSFE group. Conclusions: The use of EMD in TSFE procedures is effective in new bone formation at the apical part of the implant during the early healing period, but in the long term, no significant difference was shown between cases in which EMD was or was not used in terms of new bone formation and primary and secondary stabilization. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the effect of sonic oscillation on penetration depth and marginal adaptation of resin-based fissure sealants. Method and materials: Thirty-six extracted human third molars were randomized into three groups: in the HF group, teeth were sealed with a filled-resin-based sealant (Helioseal F); in the Sonic-HF group, teeth were sealed with Helioseal F and subjected to sonic oscillation (Compothixo Device, 140 Hz vibration frequency and ± 150 µm amplitude) before curing; in the CO group, teeth were sealed with an unfilled-resin-based sealant (Clinpro). All teeth were thermocycled for 1,500 cycles at 5°C and 55°C, then sectioned buccolingually into four sections (mesial, two middle, and distal). Sections were evaluated under SEM for marginal adaptation and scored. For penetration depth, three independent measurements from each tooth were recorded under SEM, and data were subjected to statistical analysis. Results: The group subjected to sonic oscillation (Sonic HF) resulted in significantly superior penetration depth and marginal adaptation compared with the HF group, but with no significant difference compared with the CO group. Conclusions: Sonic activation of resin-based sealant increased penetration depth into fissures and marginal adaptation to the enamel wall without decreasing filler load or compromising sealant mechanical properties. [ABSTRACT FROM AUTHOR]

This article investigated the effects of airborne-particle abrasion and nanosilica (nano-Si) infiltration treatment on the surface characteristics of dental zirconia. A total of 15 unsintered zirconia ceramic green bodies (10 x 10 x 3 mm) were divided into three groups (n = 5): Group C, no treatment after sintering; Group S, airborne-particle abrasion with 50-p.m aluminum oxide particles after sintering; and Group N, infiltration of nano-Si followed by sintering and hydrofluoric acid (HF) etching. The zirconia disks' surface roughness was analyzed by atomic force microscopy (AFM). The surface morphology of the specimens was analyzed using scanning electron microscopy (SEM), and the chemical composition was analyzed by energy-dispersive x-ray (EDX). Data were statistically analyzed by the Kruskal-Wallis test (P < .05). Zirconia surface treatments by infiltration of nano-Si, sintering, and HF etching showed multiple changes in the surface features. The surface roughness of Groups C, S, and N were 0.88 ± 0.07 µm, 1.26 ± 0.10 µm, and 1.69 ± 0.15 µm, respectively. The surface roughness of Group N was significantly higher than that of Groups C and S (P < .05). EDX analysis showed peaks that corresponded to silica (Si) after infiltration with colloidal Si that disappeared following acid etching. Infiltrating nano-Si increases the surface roughness of zirconia. The formation of retentive nanopores on the surface potentially improves the zirconia-resin cement bonding strengths. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effects of desensitizing MI Varnish (GC America) applied before or after bleaching on the mineral component of enamel and surface topography. The coronal portions of 10 freshly extracted bovine teeth were segmented for a total of 40 specimens. Enamel specimens obtained from each tooth were randomly divided into four groups (n = 10): Group A = no bleaching; Group B = bleaching with 40% hydrogen peroxide (HP); Group C = MI Varnish applied before bleaching; and Group D = MI Varnish applied after bleaching. The calcium (Ca) and phosphorus (P) levels of the specimens in each group were determined by energy dispersive spectroscopy (EDS). Morphologic changes were observed using scanning electron microscopy (SEM). One-way ANOVA and Tukey HSD tests were used for statistical analyses (α = .05). The mean Ca content of Group B was significantly lower than those of Groups A, C, and D (P < .05). The mean Ca content of Group C was significantly lower than that of Group A (P < .05). There was no significant difference in Ca content between the other groups (P > .05). The mean P content of Group A was significantly higher than those of Groups B to D (P < .05). There was no significant difference in P content between Groups B to D (P > .05). Application of MI Varnish before or after in-office bleaching was effective in reducing mineral loss. However, applying MI Varnish after bleaching was more effective. [ABSTRACT FROM AUTHOR]

The biggest challenge during periodontal regeneration in the anterior region is the prevention of soft tissue recession. Minimally invasive surgeries, particularly papilla preservation techniques and soft tissue augmentation, may significantly reduce such postoperative soft tissue recession. This article presents the vestibular incision subperiosteal tunnel access (VISTA) approach for periodontal regeneration in the anterior region. A subperiosteal tunnel prepared from a single vertical vestibular incision adjacent to the defect is used for debridement, application of enamel matrix derivative, defect grafting with corticocancellous tuberosity bone, and insertion of the connective tissue graft. Evaluation of six cases with up to 6 years of follow-up showed improvements in all clinical parameters. The probing pocket depth improved from 8.2 ± 0.75 mm initially to 2.7 ± 0.52 mm at follow-up, clinical attachment level improved from 8.5 ± 0.83 mm initially to 2.7 ± 0.52 mm at follow-up, and midfacial gingival recession of 1 mm at two sites was corrected. The papillae were stable at all sites, with an average distance of 4.8 mm from the incisal edge to the papilla tip. This technique seems to be a promising approach for achieving both esthetic and functional goals of periodontal regenerative surgery. However, experience in performing microsurgeries and harvesting tuberosity tissues may be a limitation. [ABSTRACT FROM AUTHOR]

Objective: To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing/regeneration in intrabony defects. Method and mater-ials: Intrabony defects were surgically created in the mandible of three minipigs. Twelve defects were randomly treated with either rAmelX and carrier (test group) or with the carrier only (control group). At 3 months following reconstructive surgery, the animals were euthanized, and the tissues histologically processed. Thereafter, descriptive histology, histometry, and statistical analyses were performed. Results: Postoperative clinical healing was uneventful. At the defect level, no adverse reactions (eg, suppuration, abscess formation, unusual inflammatory reaction) were observed with a good biocompatibility of the tested products. The test group yielded higher values for new cementum formation (4.81 ± 1.17 mm) compared to the control group (4.39 ± 1.71 mm) without reaching statistical significance (P= .937). Moreover, regrowth of new bone was greater in the test compared to the control group (3.51 mm and 2.97 mm, respectively, P = .309). Conclusions: The present results provided for the first-time histologic evidence for periodontal regeneration following the use of rAmelX in intrabony defects, thus pointing to the potential of this novel recombinant amelogenin as a possible alternative to regenerative materials from animal origins. [ABSTRACT FROM AUTHOR]

BackgroundEnamel is highly transparent at short wavelength infrared imaging (SWIR) wavelengths allowing the detection of dental decay without the need for ionizing radiation. The purpose of this study was to use SWIR imaging methods including cross polarization optical coherence tomography (CP-OCT), occlusal transillumination (SWIR-OT), proximal transillumination (SWIR-PT), and occlusal reflectance (SWIR-R) to image interproximal lesions in vivo and compare the sensitivity with radiography.MethodsParticipants (n = 30) aged 18-80 each with a radiopositive interproximal lesion scheduled for restoration were enrolled in the study. Studies have shown that the opposing proximal surfaces across the contact will likely also have lesions. SWIR images were acquired of the adjoining teeth at each contact with an interproximal lesion scheduled for restoration. Lesion presence and depth were assessed on each side of the contact for radiography and each SWIR imaging method. Lesions on radiographs and in CP-OCT images were identified by a single examiner while lesions in SWIR images were identified by a contrast threshold via semi-automatic image segmentation.ResultsAll SWIR imaging methods had significantly higher sensitivity (P

Objective: This study aimed to assess the remineralization efficacy of casein phosphopeptide‐amorphous calcium phosphate (CPP‐ACP), silver diamine fluoride/potassium iodide (SDF/KI), and sodium fluoride with functionalized tricalcium phosphate (NaF/fTCP) on artificial early enamel lesion using laser fluorescence and micro‐CT analysis. Methodology: On extracted impacted third molars, artificial enamel lesions were prepared. Twenty‐eight specimens were randomly assigned to four groups (n = 7 per group): a control group (artificial saliva), CPP‐ACP (GC Tooth Mousse), SDF/KI (Riva Star), and NaF/fTCP (Clinpro White varnish). Following the manufacturer's instructions, the remineralization agents were applied to demineralized surfaces. Laser fluorescence and micro‐CT were used to evaluate the remineralization efficacy of the agents and analyzes were performed during four stages: before demineralization, after demineralization, 1st day of remineralization and 30th day of remineralization. Shapiro–Wilk test, repeated measures two‐way ANOVA, and Spearman correlation tests were used for statistical analysis. A significant level of p < 0.05 was established. Results: SDF/KI significantly reduced the lesion area and lesion volume on the demineralized enamel surface after 30 days of remineralization. In the T3 period, SDF/KI increased the mineral density statistically significantly compared to the T1 period. The laser fluorescence values for all three remineralizing agents exhibited a linear decrease. A significant correlation between the fluorescence values and the mineral density was found (p = 0.01). Conclusion: All three investigated agents were showed positive remineralization efficacy on artificial enamel lesion. However, SDF/KI, containing silver diamine fluoride and potassium iodide exhibited superior than other agents in promoting remineralization. Clinical Significance: Although all three remineralization agents showed positive remineralization efficacy on artificial enamel lesions, SDF had higher remineralization performance over the other two agents. SDF has potential to prevent progression of demineralization in treating children with high caries risk in the long‐term. [ABSTRACT FROM AUTHOR]

Background: One of the primary concerns in the paediatric emergencies is traumatic dental injuries. Objective: This study aimed to create trauma in primary teeth and reveal its effects finite element analysis. Design: Three‐dimensional models were created using cone‐beam computed tomography images, representing a maxillary primary central incisor. An impact force moving at a speed of 10 m/s was simulated on the labial tooth surface in two directions: buccal and incisal. Results: The stress and deformation experienced in the adjacent tooth due to the primary tooth were higher than those generated in the permanent tooth. Forces applied in the incisal direction resulted in higher levels of stress and deformation in the permanent tooth germ. The difference between the stress and deformation values in primary teeth in the forces applied in the buccal and incisal directions is 21% and 75%, respectively; in the permanent tooth germ, this difference was 233% and 100%, respectively. Conclusions: Based on the findings of this study, it is crucial to thoroughly evaluate not only the affected primary tooth but also the adjacent teeth and the permanent tooth germ in traumatic dental injuries. This comprehensive examination allows for the anticipation and management of potential long‐term problems. [ABSTRACT FROM AUTHOR]

Dentin hypersensitivity (DH) manifests as sharp and uncomfortable pain due to the exposure of dentinal tubules (DTs) following the erosion of tooth enamel. Desensitizing agents commonly used in clinical practice have limitations such as limited depth of penetration, slow remineralization and no antimicrobial properties. To alleviate these challenges, our study designed a lactoferrin-derived amyloid nanofilm (PTLF nanofilm) inspired by the saliva-acquired membrane (SAP). The nanofilm utilises Tris(2-carboxyethyl)phosphine (TCEP) to disrupt the disulfide bonds of lactoferrin (LF) under physiological conditions. The PTLF nanofilm modifies surfaces across various substrates and effectively prevents the early and stable adhesion of cariogenic bacteria, such as Streptococcus mutans and Lactobacillus acidophilus. Simultaneously, it adheres rapidly and securely to demineralized dentin surfaces, facilitating in-situ remineralization of HAP through a simple immersion process. This leads to the formation of a remineralized layer resembling natural dentin, with an occlusion depth of dentinal tubules exceeding 80 µm after three days. The in vivo and vitro results confirm that the PTLF nanofilm possesses good biocompatibility and its ability to exert simultaneous antimicrobial effects and dentin remineralization. Accordingly, this innovative bifunctional PTLF amyloid coating offers promising prospects for the management of DH-related conditions. 1. We design a simple, fast, inexpensive, and easy-to-process PTLF nanofilm for nearly any material surface or shape. 2. The PTLF nanofilm modifies surfaces across various substrates and effectively prevents the adhesion of cariogenic bacteria, such as Streptococcus mutans and Lactobacillus acidophilus. 3. The abundant functional groups on the surface of PTLF nanofilm facilitate bioactive hydroxyapatite (HAP) formation and maintain stability at the HAP remineralization interface. [Display omitted] [ABSTRACT FROM AUTHOR]

Diet is one of the most important aspects of an animal's ecology, as it reflects direct interactions with other organisms and shapes morphology, behavior, and other life history traits. Modern birds (Neornithes) have a highly efficient and phenotypically plastic digestive system, allowing them to utilize diverse trophic resources, and digestive function has been put forth as a factor in the selectivity of the end-Cretaceous mass extinction, in which only neornithine dinosaurs survived. 1 Although diet is directly documented in several early-diverging avian lineages, 2 only a single specimen preserves evidence of diet in Enantiornithes, the dominant group of terrestrial Cretaceous birds. 3 Morphology-based predictions suggest enantiornithines were faunivores, 4,5,6 although the absence of evidence contrasts with the high preservation potential and relatively longer gut-retention times of these diets. Longipteryx is an unusual Early Cretaceous enantiornithine with an elongate rostrum; distally restricted dentition 7 ; large, recurved, and crenulated teeth 8 ; and tooth enamel much thicker than other paravians. 9 Statistical analysis of rostral length, body size, and tooth morphology predicts Longipteryx was primarily insectivorous. 4,5 Contrasting with these results, two new specimens of Longipteryx preserve gymnosperm seeds within the abdominal cavity interpreted as ingesta. Like Jeholornis , their unmacerated preservation and the absence of gastroliths indicate frugivory. 10 As in Neornithes, 11 complex diets driven by the elevated energetic demands imposed by flight, secondary rostral functions, and phylogenetic influence impede the use of morphological proxies to predict diet in early-diverging avian lineages. • Unusual enantiornithine Longipteryx with an elongate rostrum predicted to be a faunivore • Direct evidence indicates Longipteryx was a frugivore, eating gymnosperm "fruits" • Like crown birds, morphological proxies fail to predict diet in early birds Evidence of diet is rare, so morphological proxies are used to predict diet in fossils. These suggest the unusual enantiornithine bird, Longipteryx , was an insectivore. O'Connor et al. describe direct evidence it was a frugivore, indicating that, as in modern birds, the morphology of the rostrum cannot be used alone to predict diet in Mesozoic birds. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the accuracy of detecting vertical root fractures in Biodentine™-filled teeth using the Promax 3Dmax cone-beam computed tomography (CBCT) unit compared to periapical radiographs. It tested hypotheses regarding CBCT's diagnostic superiority in non-root-filled and Biodentine™-root-filled maxillary central incisors and assessed the impact of smaller field of view and lower intensity settings on detection accuracy. Materials and methods: Extracted maxillary incisors were divided into groups based on fracture status and root filling material, then placed in a Thiel-embalmed skull to simulate clinical conditions. The teeth were imaged using periapical radiographs and the CBCT unit under different settings. Fracture thickness was measured with microcomputed tomography for accuracy benchmarking. Multiple observers assessed the images, and statistical analyses were conducted to evaluate diagnostic performance. Results: Intra-rater reliabilities of consensus scores ranged from good to very good. Specificities were generally higher than sensitivities across all imaging modalities, but sensitivities remained constantly low. None of the Area Under the Curve scores exceeded 0.6, indicating poor overall accuracy for all imaging modalities. Paired comparisons of the area differences under Receiver Operator Characteristic curves revealed no significant differences between the CBCT and periapical radiograph techniques for detecting vertical root fractures in either Biodentine™-filled or non-root-filled teeth. Conclusions: There was no significant accuracy improvement of the current CBCT device (Promax 3Dmax, Planmeca, Finland) over periapical radiographs in detecting small vertical root fractures in both non-root-filled and Biodentine™-root-filled maxillary central incisors. A smaller field of view with lower intensity did not enhance detection accuracy. These results highlight the challenges in accurately detecting small VRFs, emphasizing the need for further research and technological advancements in this domain. [ABSTRACT FROM AUTHOR]

Identifying the boundary between the tooth and the resin-based composite (RBC) is difficult when replacing restorations. Ultraviolet (UV) light has been reported to assist the viewer by causing the RBC to fluoresce. Using a laboratory-grade fiberoptic spectrometer, 46 RBCs were exposed to UV light from the Woodpecker O-Star curing light. The opalescence and fluorescence were measured relative to a human tooth that contained just dentin and a tooth that contained both enamel and dentin. After these quantitative measurements, 10 RBCs with large differences in light emittance were compared qualitatively to assess their brightness when exposed to UV light compared to the dentin specimen and the specimen containing both enamel and dentin. It was found that, when exposed to UV light, some of the RBCs were less bright compared to the two samples of teeth used for comparison, but most were brighter; some were up to six times brighter. The filler appears to affect the opalescence peaks, while the resin appears to affect the fluorescence peaks. It was concluded that because RBCs emit very different levels of opalescence and fluorescence, UV light from the Woodpecker O-Star cannot be relied upon to detect all brands of RBC on the tooth. The opalescence and fluorescence can also be used to detect changes in the formulation of the RBC. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the in vitro influence of prior silane application on the microshear bond strength (μSBS) of Scotchbond Universal Plus to glass ceramic. Materials and Methods: Thirty blocks of lithium disilicate ceramic were etched with hydrofluoric acid for 20 s and distributed into Group 1 (no silane and no adhesive), Group 2 (adhesive), Group 3 (silane + adhesive). Three cylinders of resin cement were made on each ceramic block. Five blocks (n = 15 cylinders) were subjected to the μSBS test after 24 h, and the other five blocks (n = 15 cylinders) were tested after 6 months of water storage. Results: According to two‐way ANOVA, followed by Tukey's test, the means of μSBS (MPa), denoted by different letters, show significant differences (p < 0.05): after 24 h—Group 1 (31.7)B, Group 2 (43.3)A, and Group 3 (31.3)B; after 6 months—Group 1 (14.8)B, Group 2 (33.6)A, and Group 3 (30.3)A. After 6 months of storage, there was a significant decrease in μSBS for Groups 1 and 2, along with an increase in adhesive failures across all groups. Conclusions: Prior application of silane did not increase the μSBS between Scotchbond Universal Plus and ceramic, and there was degradation at the bond interface over time. Clinical Significance: Prior application of a silane agent is not necessary when using Scotchbond Universal Plus for bonding to glass ceramics. Regardless of the prior application of silane, there is degradation at the bond interface over time. [ABSTRACT FROM AUTHOR]

Aim: This study evaluated the efficacy and cytotoxicity of 35% hydrogen peroxide (HP) gel incorporated with 10% (w/w) biosilicate (BioS) on sound enamel and early‐stage enamel erosion lesions. Methods: Discs of enamel/dentin were selected, subjected to erosive cycles (0.3% citric acid, pH 2.6), and treated with (n = 8): HP (35% HP, positive control); HP_BioS [carboxymethyl cellulose (CMC) + HP + BioS]; BioS (CMC + BioS); CMC (negative control). The discs were adapted to artificial pulp chambers with the enamel exposed for bleaching, and the dentin facing toward the culture medium (Dulbecco's modified Eagle's medium [DMEM]). Bleaching was performed in three 30‐min sessions at 7‐day intervals. After bleaching, the diffusion product (DMEM extract + diffused HP) was pipetted onto MDPC‐23 odontoblastic cell line and inoculated. Color parameters (ΔL, Δa, Δb), color change (ΔE00), and changes in whiteness index (ΔWID) were determined before (T0) and after the last bleaching session (T3). Cell viability (MTT, %), H2O2 diffusion (μg/mL), oxidative cell stress (OxS), and cell fluorescence (live/dead assay, in confocal microscopy) were assessed (ANOVA/Tukey; α = 0.05). Results: No difference in ΔL, Δa, Δb, ΔE00, and ΔWID were found between HP and HP_BioS (p > 0.05). The incorporation of BioS decreased the HP diffusion into the substrates and mitigated oxidative stress in early‐stage eroded enamel (p < 0.05). HP_BioS presented significantly higher cell viability compared with HP under erosion conditions. Live/dead assay indicated that BioS_HP maintained viability with larger clusters of viable cells. Conclusion: Incorporating BioS into HP maintained bleaching effectiveness, favored cell viability, reduced the oxidative stress, and the cytotoxicity in teeth with early‐stage erosion. Clinical Significance: BioS formulation showed promising results for reducing cytotoxicity in patients seeking tooth bleaching and presenting undetectable early‐stage erosion. [ABSTRACT FROM AUTHOR]

Energy‐dispersive Laue diffraction (EDLD) is a powerful method to obtain position‐resolved texture information in inhomogeneous biological samples without the need for sample rotation. This study employs EDLD texture scanning to investigate the impact of two salivary peptides, statherin (STN) and histatin‐1 (HTN) 21 N‐terminal peptides (STN21 and HTN21), on the crystallographic structure of dental enamel. These proteins are known to play crucial roles in dental caries progression. Three healthy incisors were randomly assigned to three groups: artificially demineralized, demineralized after HTN21 peptide pre‐treatment and demineralized after STN21 peptide pre‐treatment. To understand the micro‐scale structure of the enamel, each specimen was scanned from the enamel surface to a depth of 250 µm using microbeam EDLD. Via the use of a white beam and a pixelated detector, where each pixel functions as a spectrometer, pole figures were obtained in a single exposure at each measurement point. The results revealed distinct orientations of hydroxyapatite crystallites and notable texture variation in the peptide‐treated demineralized samples compared with the demineralized control. Specifically, the peptide‐treated demineralized samples exhibited up to three orientation populations, in contrast to the demineralized control which displayed only a single orientation population. The texture index of the demineralized control (2.00 ± 0.21) was found to be lower than that of either the STN21 (2.32 ± 0.20) or the HTN21 (2.90 ± 0.46) treated samples. Hence, texture scanning with EDLD gives new insights into dental enamel crystallite orientation and links the present understanding of enamel demineralization to the underlying crystalline texture. For the first time, the feasibility of EDLD texture measurements for quantitative texture evaluation in demineralized dental enamel samples is demonstrated. [ABSTRACT FROM AUTHOR]

Objectives: In order to enhance clinical improvement of periodontal defects, the addition of enamel matrix derivatives (EMD) to open flap debridement (OFD) has been investigated. The aim of this systematic review is to figure out whether such a combination, in comparison to the treatment with OFD alone has some effects on the following outcomes: clinical attachment level gain, probing depth reduction, and gingival recessions increase. Methods: Electronic databases (PubMed, Embase, Web of Science, and Cochrane) were searched for randomized controlled trials in humans addressing the use of a combination of OFD and EMD versus a control group with OFD alone for the treatment of periodontal defects, with a minimum of 6 months of follow‐up; meta‐analysis and trial sequential analysis were then performed. Results: From a total of 204 records screened by title and abstract, 13 studies were read full‐text and eight out of them included in the meta‐analysis. Some significant differences have been demonstrated both for clinical attachment level gain and probing depth reduction between test and control groups. Conclusions: In the treatment of periodontal defects, the addition of EMD to OFD seems to be beneficial in terms of clinical attachment level gain, probing depth reduction, promoting periodontal regeneration. However, such results should be considered with caution because of the small number of studies included in the meta‐analysis and their heterogeneity. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of solutions containing aminomethacrylate copolymer (AA) and sodium fluoride (F; 225 ppm F−) or fluoride plus stannous chloride (FSn; 225 ppm F−, 800 ppm Sn2+) against enamel and dentin erosion/abrasion. Solutions F, FSn, AA, F+AA, FSn+AA, and deionized water as negative control were tested. Bovine enamel and dentin specimens (n = 13/solution/substrate) underwent a set of erosion‐abrasion cycles (0.3% citric acid [5 min, 4×/day], human saliva [1 h, 4×/day], brushing [15 s, 2×/day], and treatments [2 min, 2×/day]) for each of five days. Initial enamel erosion was evaluated using Knoop microhardness after the first and second acid challenge on day 1, and surface loss with profilometry after day 5. KOH‐soluble fluoride was assessed. Data were analyzed with ANOVA/Tukey tests. The combination of fluoride and AA resulted in higher protection against enamel erosion, whereas this was not the case for the combination of AA and FSn. All treatments protected against enamel and dentin loss. The lowest surface loss values were observed with F+AA and FSn+AA. The polymer did not significantly influence the KOH‐soluble fluoride formation on enamel/dentin specimens. The aminomethacrylate copolymer effectively enhanced the efficacy of sodium fluoride against initial erosion and improved the control of enamel and dentin wear of F and FSn solutions. [ABSTRACT FROM AUTHOR]

This study evaluated the changes in surface properties of three resin‐based restorative materials after two laser‐assisted, in‐office tooth bleaching protocols using erbium, chromium: yttrium‐scandium‐gallium‐garnet (Er,Cr:YSGG) or diode (980 nm) lasers. A nanohybrid composite (Enamel Plus HRi), a Bis‐GMA‐free composite (Enamel Plus HRi Bio Function), and a resin‐matrix CAD‐CAM ceramic (Shofu Block HC) were tested. Forty specimens for each material were prepared and divided into four groups (n = 10/group). The control specimens did not undergo any bleaching treatment, whereas group 2 received bleaching with 40% hydrogen peroxide (H2O2), while groups 3 and 4 underwent the same bleaching procedure with the use of diode (980 nm) or Er,Cr:YSGG lasers, respectively. Surface microhardness and roughness measurements were conducted using a Vickers tester and an optical profilometer. Microhardness was lower in bleached specimens, with the nanohybrid composite exhibiting the largest difference from the no bleaching group. For the Bis‐GMA‐free composite the microhardness difference between no bleaching and laser‐assisted bleaching were smaller than seen for the conventional bleaching technique. Surface roughness was higher in bleached specimens, with nanohybrid composite showing the largest differences from the control specimens. The examined laser‐assisted tooth bleaching protocols were found not to impact surface microhardness and roughness of the tested resin‐based specimens and they are deemed suitable for clinical use. [ABSTRACT FROM AUTHOR]

Purpose: To explore the latest trends in research on whitening toothpaste and to present the issues and future perspectives of these studies. Methods: An initial PubMed search was performed, followed by a meticulous manual review. A total of 543 papers were initially retrieved, and 54 final research papers were selected and analyzed through a manual review. Results: The number of studies on whitening toothpastes has significantly increased, and while initial studies primarily focused on the efficacy of various whitening toothpastes, recent studies have shifted towards investigating the potential effects on dental hard tissues such as enamel and dentin. Common active ingredients used in these whitening toothpastes include hydrogen peroxide, activated charcoal, and blue covarine. Most studies have used commercial toothpastes with fixed ingredients rather than experimentally manufactured toothpaste, and it was noted that toothpastes from specific major manufacturers were frequently used. [ABSTRACT FROM AUTHOR]

During the Late Pleistocene, stadial and interstadial fluctuations affected vegetation, fauna, and human groups that were forced to cope with these pronounced spatial–temporal climatic and environmental changes. These changes were especially abrupt during Marine Isotope Stage (MIS) 3. Here, we reconstruct the climatic trends in northern Iberia considering the stable isotopic composition of ungulate skeletal tissue found in archaeological deposits dated between 80 and 15 kacalBP. The carbon and oxygen isotopic composition preserved in the carbonate fraction of tooth enamel provides a reliable and high-resolution proxy of the food and water consumed by these animals, which is indirectly related to the local vegetation, environment, and climate, allowing us to estimate palaeotemperatures and rainfall intensity. This study presents new isotope data from 44 bovine, equid, and cervid teeth from five archaeological sites in the Vasco-Cantabrian region (El Castillo, Axlor, Labeko Koba, Aitzbitarte III interior, and El Otero) and one in northeastern Iberia (Canyars), where human evidence is attested from the Mousterian to the Magdalenian. The carbon isotope values reflect animals feeding on diverse C3 plants in open environments and point to differentiated ecological niches for equids and bovines, especially during the Aurignacian in the Vasco-Cantabrian region. Temperature estimations based on oxygen isotopic compositions and rainfall obtained from carbon isotopic compositions indicate colder and more arid conditions than nowadays for the human occupations from the Late Mousterian to the Aurignacian. The contemporary northeastern Iberian site shows slightly lower temperatures related to an arid period when animals mainly grazed in open landscapes. In the Vasco-Cantabrian region, during MIS 2, the Gravettian data reflect a landscape opening, whereas the Magdalenian points to warmer (but still arid) conditions. [ABSTRACT FROM AUTHOR]

To evaluate the effect of 1100 ppm F toothpastes supplemented with micrometric or nanosized β-CaGP (β-CaGPm/β-CaGPn) on artificial enamel remineralization, using a pH cycling model. Enamel blocks with artificial caries were randomly allocated into ten groups (n = 10), according to the toothpastes: without fluoride/β-CaGPm/β-CaGPn (negative control); 1100 ppm F (1100F); 1100F plus 0.125%, 0.25%, 0.5%, and 1.0% of β-CaGPm or β-CaGPn. The blocks were treated 2×/day with slurries of toothpastes. After pH cycling, the percentage of surface hardness recovery (%SHR); integrated loss of subsurface hardness (ΔKHN); integrated mineral loss (ΔIMR); fluoride (F), calcium (Ca), and phosphorus (P) concentrations in the enamel; polydispersity index (PdI); and zeta potential (Zp) were determined. The data were analyzed by ANOVA (p < 0.001). For Zp/PdI, no significance was observed when comparing the means (p > 0.001). The treatment with 1100F-0.25%β-CaGPn led to %SHR ∼57 higher when compared to the 1100F group (p < 0.001). The lowest ΔKHN was observed for the 1100F-0.25%β-CaGPn group (p < 0.001). The ΔIMR was lower (∼201%) for the 1100F-0.25%β-CaGPn when compared to 1100F (p < 0.001). The association of β-CaGPm and β-CaGPn to 1100F did not influence its F concentration (p > 0.001). The highest increase in Ca and P was observed for 1100F-0.25%β-CaGPn (p < 0.001). The addition of 0.25%β-CaGPn to 1100F toothpaste was able to promote an additional remineralizing effect of artificial caries lesions. [ABSTRACT FROM AUTHOR]

Background: Congenital Zika Syndrome (CZS) comprises congenital anomalies that occur in individuals, embryos or fetuses exposed to Zika virus infection during pregnancy and can result in systemic manifestations as well as alterations in the oral cavity of these children. The aim of this study was to conduct a systematic literature review of the most frequent oral and craniofacial manifestations in children aged 0 to 6 years with CZS compared to neurotypical children without CZS. In this review, a search was conducted in the PubMed, Medline, Embase, Web of Science databases and grey literature, as well as a manual search of the reference lists of the included articles, without restriction on year or language. Inclusion criteria were studies reporting oral alterations in children up to six years old or newborns with CZS, with or without a control group. Methodological quality of the studies was assessed by the Mixed Methods Appraisal Tool (MMAT). Twenty-seven articles were retrieved, 19 quantitative non-randomized and 09 quantitative descriptive studies. Three studies presented a high risk of bias. The main reported manifestations were delayed eruption (51,8%), dental enamel defects (25,9%), deep palate (29,6%), number alterations (14,8%), bruxism (29,6%), and malocclusion (25,9%). Short conclusion: CZS can lead to several manifestations of dental interest and may interfere with the individual's oral health. The pediatric dentistry thus requiring the dentist to be attentive to these changes to offer the best and comprehensive treatment to this patient. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to evaluate the color‐matching ability of OMNICHROMA composite, a single‐shade composite, using the CIE L∗a∗b∗ system and determining ΔE values. Materials and Methods: In this in vitro study, 30 intact premolar teeth were collected, cleaned, and disinfected with 0.5% thymol solution. The teeth were stored in distilled water at 37°C. A putty index calibrated the color assessment sites on buccal and lingual surfaces. Two cavities were prepared, one with 1.25 mm depth (enamel) and another with 2.25 mm depth (dentin), and restored using OMNICHROMA composite resin. The putty index measured the color of the cured composite, and ΔE between the composite and original tooth color was calculated. Statistical analysis: Data analysis included t‐tests, correlation coefficients, and Fisher's exact test (α = 0.05). Results: The mean ΔE was 2.39 in enamel cavities and 2.32 in dentin cavities, both within the clinically acceptable range (<3.3). In enamel cavities, the composite color was darker than the tooth, shifting toward green and blue shades. In dentin cavities, the composite color was lighter than the tooth, with shifts toward green and yellow shades. Color matching was slightly better in dentin cavities, but the difference was not statistically significant (p = 0.719). Conclusion: OMNICHROMA composite resin's color matching falls within the clinically acceptable range, unaffected by cavity depth. [ABSTRACT FROM AUTHOR]

Background: To investigate the anatomic features of the root furcation of permanent mandibular first molars. Methods: A total of 50 extracted mandibular first molars (25 two-rooted and 25 three-rooted) were collected and scanned using micro-computed tomography. The digital models of teeth and root canal systems were reconstructed three-dimensionally. The tooth models were displayed in parallel projection mode from buccal and distal views. Screenshots were captured and subsequently analyzed using Image-Pro Plus 6.0 software after calibration. The furcation angle, root trunk length, maximum depth and level of distal root concaves of mesial roots, and length of enamel projections were measured, and the furcation types (classified into type V, type U and type W) were detected. Statistical analysis was performed using the Shapiro-Wilk's test, one-way analysis of variance, Student's t-test and Chi-square test. Results: The mean furcation angle between the distobuccal (DB) and distolingual (DL) roots (in distal view) was the greatest (59.2°), whereas the furcation angle between the mesial and DL roots (in buccal view) was the smallest (25.4°) among the four furcation angles (all p < 0.05). Regarding the furcation types, bucco-lingual root trunk length, maximum depth and site of the distal root concavities, and enamel projection length, no significant differences were detected between the three- and two-rooted molar groups (all p > 0.05). The frequency of type V was the highest (54.0%), followed by type U (26.0%), and type W had the lowest occurrence rate (20.0%). The mean length of distal root trunk in the three-rooted mandibular molars was significantly greater than that of the buccal/lingual one (3.7 mm vs. 3.0 mm, p < 0.01). The maximum depth of the distal concavities of the mesial roots was on average 0.66 ± 0.19 mm, and the site was located at an average of 2.8 ± 1.3 mm below furcation. The mean length of buccal enamel projections was significantly longer than that of lingual ones (3.1 mm vs. 0.7 mm, p < 0.01). Conclusions: The furcation anatomy of the mandibular first molar is complex, and the presence of the DL root may further complicate its topography. A thorough understanding of these anatomic features is essential for successful periodontal treatment. [ABSTRACT FROM AUTHOR]

Interceptive orthodontics may be indicated in puppies exhibiting dental malocclusion with linguoverted deciduous mandibular canine teeth to alleviate pain and prevent teeth interlock, which may affect growth and development of the mandibles. Historically extraction of deciduous mandibular canine teeth has been recommended as soon as a malocclusion is identified, often as early as 6-8 weeks of age and no later than 12 weeks of age. This early surgical intervention of deciduous teeth extractions risks potential damage to the developing permanent canine teeth resulting in enamel defects often referred to as a Turner's tooth or Turner's hypoplasia. A search of medical records from five veterinary specialty dentistry practices was conducted to identify dogs 8-12 weeks of age who (a) underwent deciduous mandibular canine extractions for management of class 1 or class 2 malocclusion with linguoverted mandibular canine teeth, and (b) were seen for at least one recheck exam to assess for enamel defects on permanent mandibular canine teeth. Furthermore, data was collected to determine the number of dogs that required additional treatment after eruption of the permanent canine teeth due to linguoversion of the permanent canine teeth. All procedures were performed by a board-certified veterinary dentist™ or a supervised veterinary dentistry resident. Seventy-four dogs fit the inclusion criteria and had a total of 143 deciduous mandibular canine teeth extracted, out of which 13 dogs exhibited enamel defects affecting 21 permanent canine teeth. The 13 affected dogs represent a 17.5% cumulative incident rate 13/74 (95%CI 11-28%). Of all extracted teeth, 14.6% (21/143) had enamel defects affecting permanent canine teeth. Twenty-eight dogs required additional treatment to prevent the permanent mandibular canine teeth from causing trauma to the hard palate and gingiva which represented 37.8% (28/74) of all dogs in the study. Age and sex of the dog at the time of extraction were not found to be associated with the likelihood of incidence of enamel defects. This is the first reported rate of enamel defects on permanent mandibular canine teeth following extraction of deciduous mandibular canine teeth and is important to consider when advising or performing extraction of deciduous teeth in dogs. [ABSTRACT FROM AUTHOR]

ABSTRACT Clinical Significance Objective: This study evaluated the color change, surface roughness, mineral content and morphology of enamel bleached with 35% hydrogen peroxide (HP) combined with an experimental gel containing 1% titanium tetrafluoride (TiF4).Materials and Methods: Bovine enamel blocks were treated with (n = 12): (TiF) experimental gel containing 1% TiF4, (HP) 35% HP, (HPT) 35% HP + 1% TiF4 and (CT) control. Bleaching with HP was performed in 3 sessions (3 × 15 min/applications). pH, colorimetric parameters, surface roughness, mineral content and enamel morphology were determined. The pH was evaluated for 45 min. The color parameters were determined before bleaching (T0), and 14 days elapsed from the last bleaching session (T4). Surface roughness was analyzed at T0 and immediately after last bleaching session (T3). Enamel mineral content and morphology were verified at T4. Data were statistically analyzed by one‐way, two‐way ANOVA and Kruskal–Wallis (α = 0.05).Results: TiF increased surface roughness, and no differences between HP and HPT in terms of color and CO32−$$ {\mathrm{CO}}_3^{2-} $$–PO43−$$ {\mathrm{PO}}_4^{3-} $$ mineral content. Ti was detected only on TiF, and slight surface morphology changes were observed in bleached enamel.Conclusions: The combination of TiF4 and 35% HP did not interfere with the enamel bleaching effect, controlled surface roughness, and kept mineral content but promoted a minor surface morphology alteration.Due to the adverse effects of bleaching, titanium tetrafluoride (TiF4) has gained attention for its therapeutic properties, including the ability to reverse mineral loss and neutralize remineralization of mineral structures. Therefore, TiF4's remineralizing capacity may be a good alternative for incorporation into hydrogen peroxide bleaching agents. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate chitosan (CS)-based formulations loaded with 5% sodium fluoride (NaF) and/or 10% nanohydroxyapatite (nHA) to remineralize the demineralized primary tooth enamel surface. Ninety enamel blocks were demineralized and were divided into six groups (n = 15): (1) CS-based hydrogel, (2) CS-based hydrogel loaded with NaF, (3) CS-based hydrogel loaded with nHA, (4) CS-based hydrogel loaded with NaF and nHA, (5) 5% NaF varnish, and (6) negative control with no intervention. After intervention, the specimens were pH cycled by 2 h immersion in demineralizing solution and 22 h immersion in remineralizing solution for 8 days. The remineralization effects were evaluated by Vickers microhardness measurements and field emission scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (FESEM-EDS). The best mean ± SD percentage microhardness recovery in remineralized enamel (%REMH) was found in group 4 (56.90 ± 5.49). The %REMH of groups 2 (30.74 ± 3.51) and 5 (29.23 ± 5.65) were statistically the same (p = 0.943). FESEM images confirmed partial coverage of the porous demineralized enamel with a newly formed mineralized layer. Based on EDS findings, the Ca/P ratio values of the treated enamel surfaces with CS-based hydrogels ranged between 1.71 and 1.87, and the highest F content was noticed in group 2 (1.02 ± 0.03). Although, all tested CS-based hydrogels demonstrated the potential to repair demineralized enamel, nHA- and NaF-containing CS-based hydrogel showed the highest remineralization effect. We infer that this new hybrid hydrogel is a potentially useful dental material for tooth biomineralization. [ABSTRACT FROM AUTHOR]

Background: Understanding the role of cytokines in tooth development is critical for advancing dental tissue engineering. Fibroblast growth factor 9 (FGF9) is the only FGF consistently expressed throughout dental epithelial tissue, from the initiation of tooth bud formation to tooth maturation. However, mice lacking Fgf9 (Fgf9−/−) surprisingly show no obvious abnormalities in tooth development, suggesting potential compensation by other FGFs. Here we report findings from an Fgf9S99N mutation mouse model, a loss-of-function mutation with a dominant negative effect. Our study reveals that Fgf9 is crucial for dental epithelial stem cell (DESC) survival and enamel formation. Methods: To dissect the role of Fgf9 in tooth development, we performed the micro-CT, histomorphological analysis and gene expression assay in mice and embryos with S99N mutation. In addition, we assessed the effect of FGF9 on the DESC survival and dental epithelial differentiation by DESC sphere formation assay and tooth explant culture. Cell/tissue culture methods, gene expression analysis, specific inhibitors, and antibody blockage analysis were employed to explore how Fgf9 regulates enamel differentiation and DESC survival through both direct and indirect mechanisms. Results: The Fgf9S99N mutation in mice led to reduced ameloblasts, impaired enamel formation, and increased apoptosis in the cervical loop (CL). DESC sphere culture experiments revealed that FGF9 facilitated DESC survival via activating ERK/CREB signaling, without affecting cell proliferation. Furthermore, in vitro tissue culture experiments demonstrated that FGF9 promoted enamel formation in a manner dependent on the presence of mesenchyme. Interestingly, FGF9 stimulation inhibited enamel formation in isolated enamel epithelia and DESC spheres. Further investigation revealed that FGF9 supports DESC survival and promotes amelogenesis by stimulating the secretion of FGF3 and FGF10 in dental mesenchymal cells via the MAPK/ERK signaling pathway. Conclusions: Our study demonstrates that Fgf9 is essential for DESC survival and enamel formation. Fgf9 performs as a dual-directional regulator of the dental enamel epithelium, not only inhibiting DESC differentiation into ameloblasts to preserve the stemness of DESC, but also promoting ameloblast differentiation through epithelial-mesenchymal interactions. [ABSTRACT FROM AUTHOR]

Background: Tyrosine-rich amelogenin peptide (TRAP) is the main amelogenin digestion product in the developmental enamel matrix. It has been shown to promote remineralization of demineralized enamel in our previous study. However, direct evidence of the effect of TRAP on the morphology and nanostructure of crystal growth on an enamel surface has not been reported. This study aimed to examine the effect of TRAP on the morphology of calcium phosphate crystals grown on early enamel erosion using a pH-cycling model. Methods: Eroded lesions were produced in human premolars by 30-second immersion in 37% phosphoric acid. Forty-five samples of eroded human premolar enamel blocks were selected and randomly divided into 3 groups: deionized water (DDW, negative control); 100 µg/mL TRAP, and 2 ppm sodium fluoride (NaF, positive control group). For 14 days, the specimens were exposed to a pH-cycling model. Using scanning electron microscopy (SEM) and atomic force microscopy (AFM) methods, the surface morphology, calcium-phosphorus ratio, and enamel surface roughness were examined. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to assess crystal characteristics. Results: After pH-cycling, compared to the two control groups, the surface of the eroded enamel of the peptide TRAP group shows a large number of new, densely arranged rod-like crystals, parallel to each other, regularly arranged, forming an ordered structure, with crystal morphology similar to that of natural enamel. The crystals are mostly hydroxyapatite (HA). Conclusion: This study demonstrates that the peptide TRAP modulates the formation of hydroxyapatite in eroded enamel and that the newly formed crystals resemble natural enamel crystals and promote the remineralization of enamel, providing a promising biomaterial for remineralization treatment of enamel lesions. [ABSTRACT FROM AUTHOR]

Background: White spot lesions are a widespread undesirable effect, especially prevalent during fixed orthodontic treatments. The study compared the in vitro enamel remineralization potential of undemineralized dentin matrix (UDD) versus chicken eggshell powder (CESP) for artificially induced enamel lesions. Methods: 100 caries-free and sound maxillary premolars were randomly divided into four groups each contain 25 teeth: Group I (Baseline): No treatment was done to the enamel surface. Group II (Negative control): The enamel surface of the teeth underwent demineralization using demineralizing solution to create artificial carious lesions then kept in artificial saliva. Group III (CESP treated): After demineralizing the tooth surface, the teeth have been suspended in the CESP remineralizing solution. Group IV (UDD treated): After enamel demineralization, the teeth were suspended in UDD remineralizing solution. The remineralization potential was assessed by Vickers microhardness testing, scanning electron microscopic examination (SEM), and energy dispersive X-ray (EDX). Results: The current study demonstrated an increase in the mean microhardness of CESP and UDD-treated groups; however, It was nearer to the baseline level in the UDD group. SEM imaging revealed greater enamel remineralization in the UDD group compared to the remaining groups. The UDD group disclosed complete coverage for the prismatic enamel compared to the CESP group, which revealed a partially remineralized enamel surface. Interestingly, the Ca/P ratio increased significantly in the CESP group compared to the negative control group. In contrast, a higher significant increase in the mean Ca/P ratios was recorded in the UDD group compared to the test groups. Conclusion: biomimetic UDD and CESP powder should be utilized to treat enamel early carious lesions. However, UDD demonstrated the most significant remineralization potential. [ABSTRACT FROM AUTHOR]

The article presents a study on a primary care practice situated in Yorkshire, England with the aim of reviewing the management of traumatic dental injuries (TDI) within the practice. Topics discussed include the materials and methods used in the study, findings on the dentists' confidence in managing TDIs, and the introduction of a combination of staff training and practice measures to the practice.

We present the results of a study of dental pathology (specifically dental wear, caries, dental calculus, and enamel hypoplasia) carried out on 1108 teeth and empty alveoli of Bronze Age human populations that inhabited the rural settlement of Nahal Refaim, on the outskirts of the city of Jerusalem. The remains derive from a tomb complex that spans three phases of the period; Intermediate Bronze Age and the Middle Bronze Age I and Middle Bronze Age II village that replaced them (ca. 2500–1550 BC). Dental pathology can reflect diet and therefore offers a unique insight into the lifeways of past populations. The aim of this study was to investigate the extent to which the dental health of this rural population was influenced by the far‐reaching socioeconomic changes associated with the regional shift to urbanism by the Middle Bronze Age II. Although constrained by small sample sizes, we found that the pattern of dental pathology varied in a nonlinear fashion over time and discuss the factors that may have attributed to this variation. [ABSTRACT FROM AUTHOR]

This concise review provides an update on the use of calcium-based materials for the prevention of dental caries. Some calcium-based materials promote remineralization and neutralize bacterial acids, disrupting cariogenic biofilms and inhibiting bacterial growth. Medical Subject Headings of [Dental Caries] and [Calcium] were adopted to search publications. Information related to the aim of this review was extracted and summarized. Common calcium-based materials are calcium phosphate, hydroxyapatite, calcium carbonate, calcium fluoride and casein phosphopeptide–amorphous calcium phosphate (CPP-ACP). Calcium phosphate is commonly used in toothpaste. It provides calcium and phosphate ions, enhances the incorporation of fluoride into caries lesions and increases mineral density. Hydroxyapatite is a form of calcium phosphate that is chemically similar to the mineral found in teeth. It can be applied on teeth to prevent caries. Calcium carbonate can be found in toothpastes. It neutralizes bacterial acids and acts as a calcium reservoir during remineralization. Calcium fluoride is found in dental products and promotes remineralization as a source of fluoride, which can be incorporated into tooth enamel, forming fluorapatite and increasing resistance to caries. CPP-ACP is derived from milk proteins. It contains calcium and phosphate, which help to remineralize tooth enamel. CPP-ACP inhibits cariogenic bacteria. It also interacts with bacterial biofilms and disrupts their formation. These calcium-based materials can be used to boost the preventive effect of fluorides or, alternatively, as a therapy for caries prevention. [ABSTRACT FROM AUTHOR]

Bacteriotherapy is a promising option in addressing dental caries, a persistent global public health challenge with multifactorial origin, including dysbiosis. Despite the exploration of various probiotics, outcomes remain inconclusive. Objective: This study aimed to assess the inhibitory potential of L. reuteri and other potential probiotics like S. salivarius and S. oralis on the growth, adhesion, colonization, and viability of major cariogenic pathogens, comparing their probiotic efficacy. Methods: An in vitro experimental study was conducted, encompassing direct competition assays in solid and liquid co-culture tests and the characterization of adhesion to dental enamel and cell viability by life or death assay. Results: L. reuteri exhibited the significant inhibition of S. sobrinus and S. mutans growth in both solid and liquid cultures, with statistically notable differences. Scanning electron microscopy and confocal microscopy demonstrated reduced cariogenic biofilm formation when combined with L. reuteri, corroborated by diminished bacterial viability and decreased dental enamel coverage. These findings underscore L. reuteri's potential as an effective agent in caries prevention. Conclusion: The study suggests L. reuteri could serve as an effective probiotic in bacteriotherapy against dental caries. It displayed substantial inhibitory activity in vitro against cariogenic bacteria, impeding biofilm formation and adhesion, thereby impacting cell viability. [ABSTRACT FROM AUTHOR]

Key Clinical Message: In the anatomically complex terrain of the head and neck, the use of 3D intraoperative models serves as an effective verification tool, determining the size, shape, and number of foreign bodies. This allows the main operator to maximize their capacities for careful wound revision and receive real‐time information about the remaining content of the sought‐after bodies. Penetrating foreign bodies of various origins in the head and neck are uncommon, but potentially hazardous injuries. Complete removal of foreign bodies from soft tissues is essential for optimal healing, minimizing complications, and significantly reducing the risk of the need for reoperation. Despite various technological systems and safeguards available, unintentionally retained surgically placed foreign bodies remain difficult to eliminate completely. A 34‐year‐old female patient with a cut on the right side of her face who was initially treated with sutures at a general surgical clinic presented for a follow‐up examination. A foreign body was verified subcutaneously on the anterior–posterior x‐ray image on the right side. Computed tomography confirmed a total of 7 foreign bodies with a density corresponding to dental enamel, distributed subcutaneously, subfascially, and intramuscularly in the right temporal region. As part of the preoperative preparation and analysis, the bone segment of the right temporal fossa with the zygomatic bone and the glass fragments were segmented from the CT data and printed on an SLA printer. The physical 3D models were autoclave sterilized and present during surgery. The position, shape, and number of each individual glass fragment was compared with 3D‐printed one. The benefits of producing 3D models of foreign bodies are undeniable, particularly in their perioperative comparison with the removed foreign bodies from wounds. [ABSTRACT FROM AUTHOR]

The dental pulp is a highly innervated tissue transmitting pain‐related sensations in the tooth. Consequently, understanding the intricacies of its innervation mechanism in odontogenesis is crucial for gaining insights into dental pain and developing dental pain‐modulating agents. This study examined neuroregulatory molecules such as neurotrophic factors (nerve growth factor [NGF], brain‐derived neurotrophic factor [BDNF], neurotrophin‐4 [NTF‐4], and neurturin [NRTN]) and neuroinhibitory factors (slit2, ephrin isoforms and netrin‐1) in developing rat teeth with follicles. NGF, BDNF and NRTN transcriptions showed time‐dependent upregulation, particularly during the root formation stage. In contrast, NTF‐4 mRNA was highly expressed at the cap stage, but became downregulated over time. Slit2 and ephrin‐B2 expression was distinct at the cap stage and then downregulated in a time‐dependent manner. Ephrin‐A5 and netrin‐1 expression did not significantly change. Immunofluorescence analysis revealed a robust expression of both ephrin‐B2 and slit2 in the outer and inner dental epithelia of the enamel organ, a non‐neurogenic tissue, during the cap stage of 3rd molar germs. In contrast, BDNF was predominantly localized in dental papilla cells and odontoblasts during the root formation stage. These results suggest that neuroregulatory molecules, such as BDNF, slit2 and ephrin‐B2, may be important in identifying therapeutic targets for modulating dental pulp pain. [ABSTRACT FROM AUTHOR]

Within the complex world of disaster victim identification, or DVI, forensic science practitioners use a variety of investigative techniques to work toward a common goal: identification of the decedents, bringing closure to the affected communities. Identification is a complex undertaking; the event (disaster) also can be extraordinarily complex, as it may be an acute event, or one that spans months or years. Compounding this time issue, remains may be heavily fragmented, dispersed, commingled, or otherwise disrupted by either the perpetrators or the disaster itself. To help solve these complexities, we explore the use of stable isotope analysis (SIA) in DVI events. SIA can be used with a variety of body tissues (hair, nail, bone, and teeth), and each represents different time depths in a decedent's life. Bone collagen and tooth enamel carbonate are useful to reconstruct an individual's diet and source water intakes, respectively, leading to likely population or geographic origin determinations. Additionally, the carbon and nitrogen isotopic signatures of bone collagen have calculated intraperson ranges. These facts allow investigators to determine likely origin of remains using isotopic data and can be used to link skeletal elements (to an individual), or perhaps more importantly, show that remains are not linked. Application of SIA can thus speed remains identification by eliminating individuals from short lists for identification, linking or decoupling remains, and reducing the need for some DNA testing. These strategies and hypothesis tests should commence early in the DVI process to achieve maximum effectiveness. [ABSTRACT FROM AUTHOR]

Strontium (Sr) isotopes measured in fossil remains have been a useful tool to assess the geographical origin and even migrations of humans and other animals. In particular, dental enamel generally represents the ideal material, as it is dense and less prone to diagenetic replacement of Sr post-burial. However, fossil teeth can often be precious artefacts and difficult to access for destructive analysis. Here, we assess whether measuring Sr isotopes in fossil dental calculus could be used at least as a rangefinder to determine the geographical origin of an individual. We measured trace element concentrations in modern calculus (from a local dental practice), and trace element concentrations and 87Sr/86Sr ratios in human fossil calculus, dentine, and enamel from specimens collected in York, UK. Comparing trace element concentrations between modern and fossil calculus show that metals present in fossil calculus are mostly acquired post-burial, including Sr. The relationship between 87Sr/86Sr and Rb/Sr ratios in fossil calculus, dentine, and enamel suggests that the diagenetic end member would have a 87Sr/86Sr ratio consistent with the one modelled for the York region, but a low Rb/Sr. Without calculus data, dentine and enamel data would have probably suggested a lower 87Sr/86Sr ratio for a diagenetic end member, expecting high Rb/Sr values. Thus, while Sr isotopes in fossil calculus may not be useful to identify the geographical origin of an individual, they may be useful in constraining the composition of the diagenetic end member. Combining Sr isotopes in fossil dental calculus and enamel could be a more robust approach to identify geographical origin than using enamel alone. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the stress induced by clamps made of different materials on mandibular first molar teeth using finite element analysis. The tooth model to be used in the study was created using micro-CT scanner and the rubber dam clamp model was created in three dimensions (3D) using Solidworks and applied to a finite element tooth model of an intact mandibular first molar. The size of the clamp opening and the force to be applied were calculated according to the buccolingual distances of the tooth. The contact areas of the clamps on the tooth were determined and subjected to force. The stress distribution patterns and maximum von Mises stresses were calculated and compared against these forces. The most stress against these forces occurred in the enamel tissue on the distal side where the clamp was in contact with the tooth. The stress value in the stainless steel clamp (191.63 MPa) was approximately 85% higher than the clamp made of polyethylene ketone (103.85 MPa). The stress in the dentin and pulp tissue of the tooth was negligible. Clinicians should examine the enamel tissue below the equatorial line of the tooth in detail before clamp application. The forces exerted by stainless steel clamps can cause damage to the enamel tissue of the tooth or progression of an existing enamel crack. [ABSTRACT FROM AUTHOR]

This retrospective study evaluated the effects of prosthodontic crown placement on tooth vitality. Prosthodontic crown placement may be indicated for vital teeth affected by attrition, abrasion, uncomplicated crown fractures, enamel defects, and enamel hypoplasia. This study evaluated 26 vital teeth in 17 patients at the time of crown placement and after 1-year following crown placement. Dental radiographs were used to determine vitality of the 26 teeth. Twenty-five teeth were found to be vital and 1 tooth was non-vital 1-year after crown placement. These results demonstrated that tooth vitality was maintained after titanium alloy crown placement to treat crown attrition, abrasion, uncomplicated crown fractures, and enamel defects. [ABSTRACT FROM AUTHOR]

This in vitro study evaluated the influence of radiant exposure and material shade on the degree of conversion (DC) and microhardness of a resin-based composite (RBC). Sixty-four RBC specimens in shades A1E (enamel) and A4D (dentin) were light cured at a calibrated exitance of 1000 mW/cm² for 5, 10, 15, or 20 seconds, resulting in radiant exposure levels of 5. 10. 15 or 20 J/cm². The DC was determined using Fourier-transform infrared spectroscopy (n = 3 per shade per exposure level). The Knoop hardness number (KHN) was measured on the top and bottom surfaces of each specimen (n = 5 per shade per exposure level). Data were analyzed using 2- and 3-way analyses of variance and post hoc Tukey tests (α = 0.05). The RBC shade did not affect the DC (P = 0.860), and the lowest DC values were achieved with an exposure level of 5 J/cm² (P < 0.001). The shade did not affect the KHN on the top surface, but the radiant exposure level did, with the application of 5 J/cm² resulting in significantly lower values (P< 0.05). For the bottom surface, shade A1E showed significantly higher KHN values than A4D (P < 0.001). An increase in the radiant exposure led to increased DC and KHN for both shades of RBC until reaching a saturation point of 10 J/cm² for A1E and the top surface of A4D. The darker and more opaque shade was not adequately polymerized at a 2-mm depth, even when the highest radiant exposure level was applied. [ABSTRACT FROM AUTHOR]

Dental enamels of different species exhibit a wide variety of microstructural patterns that are attractive to mimic in bioinspired composites to simultaneously achieve high stiffness and superior toughness. Non-human enamel types, however, have not yet received the deserved attention and their mechanical behaviour is largely unknown. Using nanoindentation tests and finite element modelling, we investigate the mechanical behaviour of Macropus rufogriseus enamel, revealing a dominating influence of the microstructure on the effective mechanical behaviour and allowing insight into structural dependencies. We find a shallow gradient in stiffness and low degree of anisotropy over the enamel thickness that is attributed to the orientation and size of microstructural features. Most notably, M. rufogriseus 's modified radial enamel has a far simpler structural pattern than other species', but achieves great property amplification. It is therefore a very promising template for biomimetic design. The diversity of dental enamel structures in different species is well documented, but the mechanical behaviour of non-human enamel types is largely unknown. In this work, we investigate the microstructure and structure-dependent mechanical properties of marsupial enamel by nanoindentation and finite element simulations. Combining these methods gives valuable insights into the performance of modified radial enamel structures. Their stiffness and toughness stems from a unique structural design that is far less complex than well-studied human enamel types, which makes it a uniquely suitable template for biomimetic design. [Display omitted] [ABSTRACT FROM AUTHOR]

This study aimed to analyze post-coronectomy complications, chronological root survival rate (success rate) using Kaplan–Meier analysis, and postoperative radiographic signs for root extraction. A total of 555 mandibular third molar coronectomies were clinically and radiologically evaluated (mean follow-up period, 27.2 months; range, 1 month to 10.5 years). Complications were observed in 22 (4.0%) cases. Temporary inferior alveolar nerve damage was observed in one (0.2%) case, and 21 (3.8%) retained roots required extraction between 1 and 64 months after coronectomy due to dry socket (two cases, 0.4%), primary non-wound closure (10 cases, 1.8%), secondary root exposure (seven cases, 1.3%), and submucosal root eruption (two cases, 0.4%). Residual enamel after coronectomy was more significantly found on 13 (61.9%) of 21 extracted roots than on 30 (5.6%) of 534 surviving roots. Kaplan–Meier analysis revealed an overall survival rate of 93.8% at 5 years and 92.2% at 10 years. The 5-year survival rates differed significantly (p < 0.001) between the enamel-free (97.0%) and residual enamel-attached (58.3%) roots. The Cox proportional hazards model showed a hazard ratio of 20.87 (95% confidence interval, 8.58–50.72). The long-term outcomes of coronectomy were satisfactory, and a higher success rate is expected when the enamel is completely removed during coronectomy. [ABSTRACT FROM AUTHOR]

Statement of the Problem: Dental caries are among the most common oral and dental diseases affecting adults and children. To prevent caries, either the factors that cause caries should be reduced or the host resistance should be increased. Several compounds, such as bioglass, chitosan, and silver diamine fluoride (SDF), can enhance enamel remineralization. Purpose: This study was conducted to investigate the effects of chitosan, bioglass, chitosan-bioglass, and SDF compounds on remineralizing primary enamel lesions. Materials and Method: In this in vitro study, seventy-two primary canine teeth were collected. The teeth were exposed to a demineralization solution for 72 hours to create primary caries lesions. The primary Vickers microhardness test (VMT) was conducted to measure the initial values. The samples were randomly divided into six groups (n=12): Group 1: bioglass-chitosan solution; Group 2: chitosan; Group 3: bioglass solution; Group 4: SDF; Group 5: remineralization solution; Group 6: distilled water. The solutions of Groups 1, 2, and 3 were applied to the samples for 7 days, while the SDF solution was applied only once. The samples were immersed in an artificial saliva solution, which was refreshed daily. After the treatment, the final Vickers microhardness test (VMT) values were recorded. The data were analyzed statistically using a two-way ANOVA and Tukey's test (p< 0.05). Results: The results indicated a statistically significant effect of remineralizing compounds on both pre-treatment and post-treatment microhardness (p< 0.0001). However, no significant difference in microhardness was observed between the groups studied (p= 0.225). Conclusion: All the compounds utilized in this study demonstrated a significant remineralizing effect on enamel lesions caused by primary caries in primary teeth. The chitosan-bioglass and bioglass groups exhibited the highest levels of remineralization, respectively. However, the comparison between the groups yielded insignificant results due to the dispersion of the samples. Therefore, further studies with larger sample sizes are recommended. [ABSTRACT FROM AUTHOR]

(1) Background: This study aimed to establish the effect of calcium lactate enamel pretreatment related to different fluoride types and concentrations on the enamel uptake of alkali-soluble fluorides. (2) Materials: In a blind and randomized in vitro study, a total of 60 teeth are used. The first 30 teeth were cut and randomly allocated into one of the following treatments: (A) calcium lactate pretreatment followed by three different fluoride solutions; (B) the "Fluoride only" group, with slabs treated with three different fluoride solutions; (C) the "Calcium only" group, with slabs treated with calcium lactate solution; (D) slabs treated with deionized water (negative control group). The next 30 teeth underwent all the above described group procedures but were treated with lower fluoride concentrations. Fluoride was extracted from enamel using 1 M KOH solution and analyzed using a fluoride ion-specific electrode. (3) Results: The findings revealed that slabs treated with NaF following calcium lactate pretreatment exhibited significantly greater enamel uptake of alkali-soluble fluoride compared to other substrates. This significant effect was not observed at lower fluoride concentrations. (4) Conclusion: The study demonstrates that pretreatment with calcium lactate followed by treatment with NaF at 226 ppm F significantly enhances the uptake of alkali-soluble fluoride in enamel compared to other fluoride types. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Orofacial Orthopedics/Fortschritte der Kieferorthopadie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Teeth are the anatomical tissue with the highest resistance to the action of chemical and physical agents. This is one of the reasons that make teeth particularly useful in the identification process of skeletonized and carbonized human remains. The aim of this research is to analyze the colorimetric changes in the enamel of teeth subjected to high temperatures to develop a reproducible colorimetric cataloging method. Methods: Six groups of 21 human teeth extracted from private clinics and from a Dental School for therapeutic reasons were used and subjected to three temperature ranges in a laboratory furnace: 400 °C, 700 °C, and 1000 °C. For each temperature, two time periods of 20 min and 60 min were chosen. Each group of dental elements was analyzed using a dental spectrophotometer to extract the colorimetric data of the crown. The obtained color coordinates were subsequently converted into Red–Green–Blue (RGB) values. The two predominant colors were also selected to create average colorimetric values, which demonstrate the change in color hue according to temperature. The groups of teeth subjected to 20 min at 400 °C exhibited a dark gray coloration, while the teeth subjected to 20 min at 700 °C showed a general increase in color brightness with beige–blueish hues. Results: The teeth subjected to 20 min at 1000 °C displayed progressively lighter shades with pinkish reflections. The teeth subjected to 60 min at the same temperatures demonstrated a general increase in brightness, making differentiation more challenging, except for the group of teeth burned at 400 °C, which showed light gray–blueish tones. Conclusions: This study further supports the existing literature on the correlation between colorimetric shifts in carbonized teeth and the maximum temperature reached, providing valuable assistance to forensic pathology and the forensic dental identification of burnt human remains. Additionally, this research has led to the development of a standardized colorimetric patented scale for the observation and examination of burnt human teeth. [ABSTRACT FROM AUTHOR]