Dentin Surfaces Research Articles

Characterization of nanoceria-modified silicone soft liners: Surface morphology, hardness, wettability, cytotoxicity, and antifungal properties in artificial saliva – An in vitro study

Statement of problemSoft liners are essential for denture wearers, which aids in the healing of soft tissue injuries caused by rough denture base surfaces. Silicone soft liners, while effective, can accumulate biofilm over time, necessitating enhancement. PurposeThis in vitro study aimed to assess the efficacy of silicone soft liners incorporating varying concentrations of cerium oxide nanoparticles. Materials and methodsA stainless-steel die as per ISO standard 10139-2-2018 (35 × 6 mm), Using G*Power 3.0.10 software, 400 samples were prepared with 95 % confidence interval and 80 % power. Samples were divided into five groups: surface morphology (Group A), surface hardness (Group B), wettability (Group C), cytotoxicity (Group D), and antifungal property (Group E). Each group was subdivided based on cerium oxide nanoparticle concentrations. Samples were stored in artificial saliva until evaluation. Surface morphology was examined via scanning electron microscopy (SEM), surface hardness using Shore A Durometer, wettability by drop shape analysis, cytotoxicity via MTT assay, and antifungal properties using crystal violet staining.Data were assessed for normal distribution using Kolmogorov-Smirnov and Shapiro-Wilk tests. ResultsSEM analysis showed optimal nanoparticle dispersion in Group A2(0.25 %) and A3 (0.5 %). Group B2 (0.25 %) exhibited the lowest mean surface hardness, decreasing from day 1 to day 30. Group C3 demonstrated the most hydrophobic surface across days. Group D2 exhibited the least cytotoxicity at all time intervals. Group E4 displayed the highest antifungal activity. ConclusionWithin study limitations, silicone soft liners modified with 0.25 % and 0.5 % cerium oxide nanoparticles exhibited superior properties in surface hardness and cytotoxicity. Optimal surface morphology and wettability were observed with 0.5 % concentration, while antifungal efficacy peaked at 1 %. These findings suggest clinical potential for treating damaged oral tissues. Clinical implicationsSoft liners modified with 0.25 % and 0.5 % cerium oxide nanoparticles may benefit patients with oral tissue abuse, offering enhanced therapeutic properties.

The effect of laser therapy for the treatment of dentin hypersensitivity on surface roughness and bacterial adhesion

The aim of the study was to measure the degree of dentine surface roughness caused by five distinct lasers used to treat dentine hypersensitivity, as well as to evaluate the subsequent bacterial colonization on these irradiated surfaces. Sixty human maxillary premolar teeth without caries or restoration which were extracted for periodontal reasons were used in this study. Five different types of lasers were applied to the root dentin surface. Tested samples were divided into six groups of 10 samples each; control, diode (810 nm), diode (980 nm), Nd: YAG, Er: YAG, and Er, Cr: YSGG laser groups. The arithmetic mean of the surface roughness values (Ra) and the average roughness over a measurement area (Sa) were measured pre- and post-application using any of the laser types. Swab samples were then collected from the dentin surface. Following a 24-hour incubation period at 37 °C, the colony forming units were counted using a stereoscope. The results demonstrated a statistically significant difference in the surface roughness values pre- and post-application (Ra and Sa, respectively) in the Er, Cr: YSGG laser group (p = 0.037,p = 0.007). No significant difference was observed in the other groups (p > 0.05). There was no statistically significant difference in the number of bacterial colonies observed between the test and control groups. Diode and Nd: YAG lasers showed either a decrease or no change in surface roughness; however, the hard tissue lasers (Er: YAG, Er, Cr: YSGG) showed an increase. The Er: YAG and Nd: YAG laser groups exhibited decreased bacterial adhesion compared to the other groups.

Evolutionary Design of Self-Templated Supramolecular Fibrils Using M13 Bacteriophage for Tissue Engineering.

Biomaterials in nature form hierarchical structures and functions across various length scales through binding and assembly processes. Inspired by nature, we developed hierarchically organized tissue engineering materials through evolutionary screening and self-templating assembly. Leveraging the M13 bacteriophage (phage), we employed an evolutionary selection process against hydroxyapatite (HA) to isolate HA-binding phage (HAPh). The newly discovered phage exhibits a bimodal length, comprising 950 nm and 240 nm, where the synergistic effect of these dual lengths promotes the formation of supramolecular fibrils with periodic banded structures. The assembled HAPh fibrils show the capability of HA mineralization and the directional growth of osteoblast cells. When applied to a dentin surface, it induces the regeneration of dentin-like tissue structures, showcasing its potential applications as a scaffold in tissue engineering. The integration of evolutionary screening and self-templating assembly holds promise for the future development of hierarchically organized tissue engineering materials.

In Vitro Inhibitory Effect of Silver Diamine Fluoride Combined with Potassium Iodide against Mixed-Species Biofilm Formation on Human Root Dentin.

Applying a saturated potassium iodide (KI) solution immediately after silver diamine fluoride (SDF) application may affect the inhibitory effects of SDF on biofilm formation. This study compared the efficacy of 38% SDF with and without KI on preventing mixed-species biofilm formation on human root dentin surfaces and assessed ion incorporation into root dentin. The biofilms, composed of Streptococcus mutans, Lactobacillus rhamnosus, and Actinomyces naeslundii, were grown on specimen surfaces treated with either SDF or SDF + KI. After 24 h, the biofilms were evaluated using scanning electron microscopy, live/dead staining, adenosine triphosphate (ATP) assays, colony-forming unit (CFU) counts, and quantitative polymerase chain reaction. A Mann-Whitney U test was used to compare the results between the groups. Ion incorporation was assessed using an electron probe microanalyzer. The relative ATP content in the SDF + KI group was significantly higher than that in the SDF group (p < 0.05). However, biofilm morphology and the logarithmic reduction in CFUs and bacterial DNA were comparable across the groups. The SDF + KI treatment resulted in less silver and fluoride ion incorporation than that yielded by SDF alone. The inhibitory effects of SDF and SDF + KI on mixed-species biofilm formation were almost equivalent, although KI application affected the ion incorporation.

In situ deposition of amorphous zirconia to enhance corrosion and tribocorrosion resistance of dentin surface

With global aging and the prevalence of acidic diets, dentin exposure is becoming commonplace; thus, it is necessary to develop a treatment technology that combines resistance to wear, corrosion, and tribocorrosion. Herein, we present a promising treatment strategy that induces in situ deposition of amorphous zirconia on exposed dentin surface. The deposited amorphous zirconia bonds to dentin surface through strong chemical connection, and acts as a protective layer against acid attack and contact wear due to its acid-inertness and good mechanical properties. Consequently, the treated dentin surface exhibits encouraging corrosion and tribocorrosion performance. The deposit also provides antibacterial protection.

Investigation of periodontal tissue regeneration using octacalcium phosphate and collagen composite

ObjectiveThis study aimed to investigate periodontal tissue regenerative potential of octacalcium phosphate (OCP) and collagen composite (OCPcol), recognized as excellent bone-regenerative materials, in artificial bone defect models using beagle dogs. This study specifically assessed the efficacy of OCPcol in periodontal soft-tissue regeneration. MethodsOCPcol was implanted in bone defects adjacent to the roots of the left mandibular third and fourth premolars in six beagle dogs (OCP group), while five dogs did not receive OCPcol (control group). The dogs were observed for 3 months. The specimens were evaluated radiologically and histologically. ResultsMicrocomputed tomography revealed bone regeneration originating from the lateral cortical bone surface adjacent to the created defect. The superficial layer of the regenerated bone was cortical bone-like and continuous with the upper and lower alveolar bone. The bone was regenerated by maintaining a continuous void in the periodontal ligament space above and below the dentinal defect. Dental defects of roots were not regenerated. The control group did not exhibit sufficient bone regeneration. Histologically, in the OCP group, formation of new cementum was observed on the outer surface of the root dentin, with connective tissue attachment and an oblique-running periodontal ligament in the space between the new bone and dentin. However, the dentinal defects were not regenerated． ConclusionsAlveolar bone and periodontal ligament regenerated when OCPcol was implanted into a bone and dentinal defect created around a natural tooth root. These results suggest that OCPcol effectively regenerates periodontal tissue, without ankylosis.

An in vitro assessment of the influence of dentinal pretreatment with chlorhexidine, nonthermal atmospheric plasma, chitosan, and proanthocyanidins on shear bond strength to composite.

Dentin biomodification has been emphasized as a means of improving the bond between composite resin and tooth surface, consequently enhancing its longevity. To evaluate the shear bond strength (SBS) of dentin after pretreatment with 2% chlorhexidine (CHX), 2% chitosan, nonthermal atmospheric plasma (NTAP), proanthocyanidins (5% pine bark ((PB) and 5% bromelain). The study was designed as an in vitro investigation. Sixty extracted mandibular molars (n = 60) were gathered for this in vitro research. The teeth were decoronated to expose the dentinal surface. All samples have been etched with 37% phosphoric acid and then pretreated with respective dentin biomodifiers. Group I (control): No pretreatment was done, Group II: 2% CHX, Group III: NTAP, Group IV: 5% PB, Group V: 2% chitosan, Group VI: 5% bromelain. Specimens were evaluated for the SBS test, which was done under the instron universal machine at a speed of 1 mm/min after a bonding agent and composite build-up were applied. While Group I had the lowest SBS (10.391.59Mpa), Group V had the highest SBS (30.111.53 Mpa). Pretreatment of the dentin enhanced the SBS of dentin to composite. When utilized after etching, dentin biomodification increased all experimental group's bond strength in contrast to the control. The highest SBS values were recorded with 2% chitosan, followed by NTAP.

Potential Remineralizing Effect of Cuttlefish Bone and Eggshell Powder’s on Demineralized Human Enamel (an invitro study)

Dental treatment has been shifted towards more conservative approaches that focus on caries identification at early stage, remineralization of dental surfaces, and preservation of tooth structure. So that, newly safe alternative methods for teeth remineralization have to be created. There is minimal evidence to support the use of eggshell powder (ESP) for remineralizing enamel and Cuttlefish bone powder (CBP) as an alternative calcium source in bone replacement.The aim of this study is to evaluate the capacity of eggshell powder (ESP) and cuttlefish bone powder (CBP) solutions to remineralize early initiated demineralized lesions of enamel in permanent teeth. 40 extracted premolars were divided into four groups: Group1 (which received no treatment), Group2 (which was subjected todemineralizing solution), Group3 (which was subjected todemineralizing solution and then treated with CBP solution), and Group4 (which was subjected todemineralizing solution and then treated with ESP solution). All groups were prepared forscanning electron microscope (SEM), X-ray microanalysis (EDAX), and microhardness evaluation. The demineralization process significantly changed the surface structure of the enamel, resulting in erosive lesions. CBP and ESP solutions both had a reparative effect, enhanced surface morphology, and increased Ca and P content and microhardness.

Effect of silver diamine fluoride and potassium iodide on shear bond strength for glass ionomer cement to primary dentine.

Silver diamine fluoride (SDF) is a highly effective topical fluoride for halting dental caries; however, it darkens both teeth and restorations. Therefore, it is of interest to assess the shear bond strength (SBS) of glass ionomer cement (GIC) to caries-affected dentin treated with SDF alone and SDF followed by KI. Forty primary molar samples were prepared to reveal a flat dentin surface and were randomly assigned to two groups. In group A, the dentin surfaces were pre-treated with 38% SDF, while in group B, the dentin was treated first with SDF and then with KI before being restored with GIC. The SBS was measured using a universal testing machine. The results show that teeth pre-treated with both SDF and KI demonstrated significantly improved bond strength of GIC to dentin compared to SDF treatment alone.

Effect of inositol hexaphosphate acid versus polyacrylic acid on dentin properties and adhesion of a self-adhesive restorative material to dentin

ObjectiveThis study evaluated the effect of 2% inositol hexaphosphate (IP6) and 10% polyacrylic acid (PAA) on dentin surface micromorphology, matrix/mineral ratio, microhardness, and resin−dentin shear bond strength (SBS) of a self-adhesive restorative material (Surefil™ One; Dentsply Sirona, Konstanz, Germany). Materials and methodsHuman permanent molar mid-coronal dentin discs were either not treated (control), conditioned with 10% PAA (Dentin Conditioner, GC, Tokyo, Japan) for 20 s, or etched with 2% IP6 for 20 s. Dentin surface micromorphology (etching pattern), matrix/mineral ratio, and microhardness were characterized by a scanning electron microscope (SEM), a confocal Raman microscope and a microhardness tester using the Vickers indenter, respectively. Sound molars were cut flat, mounted, surface treated and restored with Surefil™ One, Dentsply. The shear bond strength (SBS) was evaluated using a universal testing machine at 24 h and after 10k thermo-cycles. The failure modes were assessed. One-way and two-way analysis of variance (ANOVA) followed by the Tukey's multiple comparisons test was used for the statistical analysis. ResultsIP6 etching resulted in a more aggressive and uniform etching pattern compared with PAA. The mineral/matrix and Vickers microhardness of IP6-etched dentin were significantly less than those of PAA-conditioned dentin. IP6 etching significantly improved the resin−dentin SBS compared with the control group (no treatment) at 24 h and after thermo-cycling. Adhesive failures were the most predominant in all study groups. ConclusionInositol hexaphosphate acid etching deteriorated dentin microhardness and resulted in substantial demineralization, however, it eliminated the dentin smear layer completely and created marked micromorphological alteration at dentin surface, significantly increasing the resin−dentin SBS of a self-adhesive restorative material.

(Kesan Rawatan Permukaan pada Ikatan Struktur Mikro antara Muka Zirkonia-Dentin terhadap Saiz Zarah Serbuk Zirkonia yang Berbeza)

Zirconia-based materials have emerged as promising resources for dental restoration applications owing to their excellent strength and aesthetic appearance. In clinical practices, surface treatment on zirconia is essential to ensure enhanced dental bonding. In this study, a novel method was used to produce zirconia block, and the influence of surface treatment on zirconia-dentine microstructure bonding interface was investigated for different particle sizes of zirconia powder. The particle sizes used in this study were 90 and 30 nm on the basis of manufacturer claims. A zirconia block of both particle sizes underwent surface treatment airborne-particle abrasion (50 μm, 0.4 MPa). Dentine specimens were prepared from extracted premolars stored in 0.1% tymol solution before being randomly cemented with the zirconia block sample by using self-adhesive resin cement (RelyX U2000 Clicker, 3M) and then light polymerised. The results after surface treatment showed higher surface roughness values for 90 and 30 nm at 0.17 and 0.18 μm, respectively, than those of the sample without surface treatment at 0.05 and 0.06 μm, respectively, showing no significant difference between particle sizes. Surface treatment improved the bonding of zirconia because the surface roughness allowed for enhanced interlocking of the cement onto the zirconia surface. However, the unbonded dentine and cement was due to the existence of a smear layer on the dentine surface that prevented the selfadhesive resin cement to work well with the dentine surface. Thus, dentine primer must be used to chemically remove the layer and allow for proper bonding between the resin cement and dentine surface.

Comparison of a self-adhesive resin cement, a conventional and a bulk-fill resin composite for luting of indirect restorative materials; the effect of thickness and material factors on translucence, monomer conversion and resin-dentin bond strength

Introduction: With developing technology, the search for the most ideal material to be used in the cementation of indirect restorations continues. To determine the effect of thickness and material factors on monomer conversion, translucency, and resin-dentin bond strength in luting indirect restorative materials (IRM) of different thicknesses using a resin cement, a conventional and a bulk-fill resin composite. Materials and methods: Samples of lithium disilicate glass-ceramic material (IPS e.max) and ceramic-resin hybrid material (Lava Ultimate) in 2 and 4 mm thicknesses, were luted using RelyX U200 (a self-adhesive resin cement), X-tra fil (a bulk-fill resin composite) and Z250 (a conventional microhybride resin composite) to the dentin surface and subjected to bond strength test after thermal cycle. In addition, the translucency parameter (TP) of the prepared blocks and the degree of conversion (DC) of the luting materials were investigated. The data was statistically analyzed. Results: The bond strength of X-tra fil and Z250 was statistically higher than RelyX U200 (p0.05). The increase in thickness decreased the TP of IRMs and the DC of resins underlying Lava (p0.05). Conclusion: Conventional and bulk-fill resin composites can be alternative luting materials to resin cements. Thickness increase did not change bond strength, while decreased TP, and DC only for Lava Ultimate.

Effects on dentin nanomechanical properties, cell viability and dentin wettability of a novel plant-derived biomodification monomer

ObjectivesTo evaluate the effects of dentin biomodification agents (Proanthocyanidin (PAC), Cardol (CD) and Cardol-methacrylate (CDMA) on dentin hydrophilicity by contact angle measurement, viability of dental pulp stem cells (DPSCs) and nanomechanical properties of the hybrid layer (HL). MethodsCDMA monomer was synthesized from cardol through methacrylic acid esterification. Human extracted third molars were used for all experiments. For nanomechanical tests, specimens were divided in four groups according to the primer solutions (CD, CDMA, PAC and control) were applied before adhesive and composite coating. Nanomechanical properties of the HL were analyzed by nanoindentation test using a Berkovich probe in a nanoindenter. Wettability test was performed on dentin surfaces after 1 min biomodification and measured by contact angle analysis. Cytotoxicity was assessed by a MTT assay with DPSCs after 48 and 72 h. Data were analyzed with Student's t test or Two-way ANOVA and Tukey HSD test (p < 0.05). ResultsCD and CDMA solutions achieved greater hydrophobicity and increased the water-surface contact angles when compared to PAC and control groups (p < 0.05). PAC group showed a greater reduction of elastic modulus in nanoindentation experiments when compared to CD and CDMA groups (p < 0.05) after 4 months of aging. CD inhibited cell proliferation compared to all further materials (p < 0.05), whilst CDMA and PAC indicated no cell cytotoxicity to human DPSCs. SignificanceCardol-methacrylate provided significantly higher hydrophobicity to dentin and demonstrated remarkable potential as collagen crosslinking, attaining the lowest decrease of HL’s mechanical properties. Furthermore, such monomer did not affect pulp cytotoxicity, thereby highlighting promising feasibility for clinical applications.

EVALUATION OF CANDIDA SPP. ADHERENCE TO 3D-PRINTED AND HEAT-CURED PMMA RESIN DENTURES

Introduction: Despite the progress of additive manufacturing, there are different opinions regarding microbial adhesion on the surface of 3D printed dentures and the biocompatiability of the materials. The purpose of this in-vivo study was to determine the presence of Candida species in the saliva, oral mucosa and on dentures of patients wearing heat-cured polymethylmethacrylate (PMMA) and 3D-printed prosthetic appliances after a three-month period of observation. Materials and methods: The clinical study included 40 edentulous patients, divided into two groups - first group (A) –wearing conventional dentures and second group (B) – wearing 3D printed dentures. It was used chrom agar Candida (Bio Merieux) for identification and quantity assessment of the presence of Candida spp. and spectrophotometric analysis using VITEK MS (Bio Merieux). Results: After three months of wearing the dentures, Candida spp was not isolated in the saliva in 60% of patients in group A and 70% of group B, with no statistically significant difference between the results before the treatment and after the third month. In the third month, Candida spp was isolated from the oral mucosa of 20% of group A and in group B – 10%, with no significant difference between the groups (p&lt;0.05). No Candida spp was isolated from 90% of denture surfaces in both groups. Conclusion: The adhesion of Candida spp. to 3D printed dentures is not higher than conventional dentures made from heat-curing resin. Also, there is no difference between the amount of Candida spp. in the saliva, oral mucosa and denture surfaces.

Searching for a relationship between the elemental composition of archaeological bones and the occurrence of caries.

Although the macroscopic assessment of dental caries and the assessment of bone elemental composition are quite different, efforts can be made to identify commonalities in the assessment of health and nutritional quality. Both indicators are correlated with dietary habits and are dependent on taphonomic processes occurring in the postmortem substrate. However, teeth exhibit structural resilience of their hard tissues to adverse environmental factors. The aim of the study was to establish a correlation between the elemental composition of bones and the presence of carious lesions. The study material consisted of the following skeletal parts: 161 permanent teeth from 36 individuals and bridge fragments of 36 ribs. The presence of caries was assessed visually using a modified International Caries Detection & Assessment System (ICDAS II) scale. The rib samples were subjected to elemental analysis (zinc (Zn), iron (Fe), magnesium (Mg), calcium (Ca), phosphorus (P), strontium (Sr), barium (Ba)) using spectroscopic methods. The odontological and chemical analyses did not reveal any statistically significant relationships between the Ca/P diagenesis index and dental features. Postmortem tooth loss showed a weak correlation with the diagenesis index. Discoloration, cracks and flaking of the dental crown surfaces may be associated with the intensity of Ca/P diagenesis. However, no significant correlation was found between these phenomena. Among other elements, only Zn levels exhibited a correlation with the caries index.

Pre-Sealing of Endodontic Access Cavities for the Preservation of Anterior Teeth Fracture Resistance.

Sodium hypochlorite solution (NaOCl) is an effective canal irrigant but interferes with the mechanical features of dentin and the bonding capability of adhesives when restoring endodontically treated teeth. This study evaluated whether access cavity resin sealing before using canal irrigant would augment the resistance of endodontically treated anterior teeth against fracture. Sixty maxillary incisors underwent endodontic treatment in five groups (n = 12). Irrigation with 5.25% NaOCl and 17% ethylenediaminetetraacetic acid (EDTA) was performed in all groups except for Group 5. After root canal obturation, in Group 1, the access cavity was kept unrestored. In Group 2, immediate restoration after obturation was achieved. For Group 3, delayed restoration after 1 week was provided. In Group 4 (pre-sealed), before canal irrigation, the dentin surface of access cavities was sealed using self-adhesive composite resin (Vertise Flow) and then restored after obturation. In Group 5, which was saline irrigated, immediate restoration was performed. After storage and thermal cycling for 5000 cycles at 5°C-55°C with a dwell time of 15 s and a transfer time of 5 s, teeth were statically loaded by a universal testing machine until a fracture occurred. Data were collected as the fracture resistance (FR) and analyzed using the one-way analysis of variance and Tukey's tests. FR significantly differed between all groups (p < 0.001). The lowest FR was recorded in the unrestored group (284 ± 86 N), which was not statistically different from the immediately restored group (p = 0.065). The pre-sealed group exhibited the highest FR value (810 ± 127 N, p ≤ 0.02 vs. other groups). The FR of the saline-irrigated and delayed restored groups was almost similar (p = 0.13). NaOCl/EDTA irrigation resulted in an adverse effect on FR. Delayed restoration could reduce this adverse effect. Access cavity pre-sealing with flowable composites led to a higher FR than conventional methods and may be considered an effective step during treatment procedures.

Evaluation of Physical Properties in Carboxymethyl Chitosan Modified Glass Ionomer Cements and the Effect for Dentin Remineralization: SEM/EDX, Compressive Strength, and Ca/P Ratio.

The aim of this article was to evaluate the effects of modifying glass ionomer cement (GIC) with carboxymethyl chitosan (CMC) on surface morphology and remineralization outcomes by examining dentin morphology and calcium ion composition changes. Thirty holes in a cylindrical acrylic mold were filled with three groups of restorative materials: GIC, GIC modified with CMC (GIC-CMC) 5%, and GIC-CMC10%. The surface morphology of each group's materials was observed using scanning electron microscopy (SEM). The compressive strength measurement was performed using a universal testing machine. The dentin remineralization process was performed by applying GIC, GIC-CMC5%, and GIC-CMC10% materials for 14 days on demineralized dentin cavities treated with 17% ethylenediamine tetraacetic acid (EDTA) for 7 days. A morphological evaluation was conducted using SEM. The calcium ion composition and calcium-to-phosphorous (Ca/P) ratio were examined using an energy-dispersive X-ray (EDX). The Kruskal-Wallis and post-hoc Mann-Whitney U tests were performed to compare all four groups of calcium ions (p < 0.05). The modification of GIC with CMC affected the morphological changes in the materials in the form of reduced porosity and increased fractures. A significant difference was found in compressive strength between the GIC-CMC modification materials of GIC-CMC5% and GIC-CMC10% and the GIC control group. The dentin tubule morphology and surface changes were observed after applying GIC, GIC-CMC5%, and GIC-CMC10% materials for 14 days, as evaluated by SEM. The EDX examination showed an increase in calcium ion content and hydroxyapatite formation (Ca/P ratio) after applying the GIC-CMC10% material. The surface porosity of the GIC modification material with the addition of CMC tended to decrease. However, an increase in cracked surfaces that widened, along with the rise in CMC percentage, was found. This modification also reduced the compressive strength of the materials, with the lowest average yield at 10% CMC addition. Therefore, the modification of GIC with CMC affects changes in morphology, calcium ion composition, and Ca/P ratio in demineralized dentin.

Depth distortion and angular deviation of a fully guided tooth-supported static surgical guide in a partially edentulous patient: A systematic review and meta-analysis.

This systematic review and meta-analysis aimed to evaluate the depth distortion and angular deviation of fully-guided tooth-supported static surgical guides (FTSG) in partially edentulous arches compared to partially guided surgical guides or freehand. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was registered in the Open Science Framework (OSF). The formulated population, intervention, comparison, and outcome (PICO) question was: "In partially edentulous arches, what are the depth distortion and angular deviation of FTSG compared to partially guided surgical guides or freehand?" The search strategy involved four main electronic databases, and an additional manual search was completed in November 2023 by following an established search strategy. Initial inclusion was based on titles and abstracts, followed by a detailed review of selected studies, and clinical studies that evaluated the angular deviations or depth distortion in FTSG in partial arches, compared to partially guided surgical guides or freehand, were included. In FTSG, two surgical approaches were compared: open flap and flapless techniques, and two digital methods were assessed for surgical guide design with fiducial markers or dental surfaces. A qualitative analysis for clinical studies was used to assess the risk of bias. The certainty of the evidence was assessed according to the grading of recommendations, assessment, development, and evaluations (GRADE) system. In addition, a single-arm meta-analysis of proportion was performed to evaluate the angular deviation of freehand and FTSG. Ten studies, published between 2018 and 2023, met the eligibility criteria. Among them, 10 studies reported angular deviations ranging from -0.32° to 4.96° for FTSG. Regarding FTSG surgical approaches, seven studies examined the open flap technique for FTSG, reporting mean angular deviations ranging from 2.03° to 4.23°, and four studies evaluated flapless FTSG, reporting angular deviations ranging from -0.32° to 3.38°. Six studies assessed the freehand surgical approach, reporting angular deviations ranging from 1.40° to 7.36°. The mean depth distortion ranged between 0.19mm to 2.05mm for open flap FTSG, and between 0.15mm to 0.45mm for flapless FTSG. For partially guided surgical guides, two studies reported angular deviations ranging from 0.59° to 3.44°. Seven studies were eligible for meta-analysis, focusing on the FTSG in open flap technique, with high heterogeneity (I2 (95%CI) = 92.3% (88.7%-96.4%)). In contrast, heterogeneity was low in studies comparing freehand versus FTSG in open flap techniques (I2 (95%CI) = 21.3% (0.0%-67.8%)), favoring the FTSG surgical approach. In partially edentulous arches, FTSG systems exhibited less angular deviation than freehand and partially guided surgical guides. Flapless surgical approaches were associated with reduced angular deviation and depth distortion, suggesting a potential preference for the FTSG method in these procedures.

Microbiological and functional traits of peri-implant mucositis and correlation with disease severity.

Osseointegrated dental implants replace missing teeth and create an artificial surface for biofilms of complex microbial communities to grow. These biofilms on implants and dental surfaces can trigger infection and inflammation in the surrounding tissue. This study investigated the microbial characteristics of peri-implant mucositis (PM) and explored the correlation between microbial ecological imbalance, community function, and disease severity by comparing the submucosal microflora from PM with those of healthy inter-subject implants and intra-subject gingivitis (G) within a group of 32 individuals. We analyzed submucosal plaques from PM, healthy implant (HI), and G sites using metagenome shotgun sequencing. The bacterial diversity of HIs was higher than that of PM, according to the Simpson index. Beta diversity revealed differences in taxonomic and functional compositions across the groups. Linear discriminant analysis of the effect size identified 15 genera and 37 species as biomarkers that distinguished PM from HIs. Pathways involving cell motility and protein processing in the endoplasmic reticulum were upregulated in PM, while pathways related to the metabolism of cofactors and vitamins were downregulated. Microbial dysbiosis correlated positively with the severity of clinical inflammation measured by the sulcus bleeding index (SBI) in PM. Prevotella and protein processing in the endoplasmic reticulum also correlated positively with the SBI. Our study revealed PM's microbiological and functional traits and suggested the importance of certain functions in disease severity.IMPORTANCEPeri-implant mucositis is an early stage in the progression of peri-implantitis. The high prevalence of it has been a threat to the widespread use of implant prosthodontics. The link between the submucosal microbiome and peri-implant mucositis was demonstrated previously. Nevertheless, the taxonomic and functional composition of the peri-implant mucositis microbiome remains controversial. In this study, we comprehensively characterize the microbial signature of peri-implant mucositis and for the first time, we investigate the correlations between microbial dysbiosis, functional potential, and disease severity. With the help of metagenomic sequencing, we find the positive correlations between microbial dysbiosis, genus Prevotella, pathway of protein processing in the endoplasmic reticulum, and more severe mucosal bleeding in the peri-implant mucositis. Our studies offer insight into the pathogenesis of peri-implant mucositis by providing information on the relationships between community function and disease severity.

Effect of herbal irrigants on surface roughness of intraradicular dentin using quantitative method of 3D surface texture analysis

Replacing the conventional endodontic irrigants with herbal agents could avoid complications associated with using sodium hypochlorite (NaOCl). Endodontic irrigants alter the surface roughness of the dentinal wall surface, which affects sealer mechanical retention. This study aimed to assess the effect of experimental herbal Moringa oleifera and orange peel extract irrigant on intraradicular dentin (IRD) surface roughness using quantitative 3D surface analysis by scanning electron microscopy (SEM) regarding the smear layer assessment. Sixty human root sections were divided into four groups (n = 15): NaOCl combined with 17% ethylenediaminetetraacetic acid (EDTA); negative control (saline); moringa extract (MO); and orange oil (OO). SEM images were assessed quantitatively for surface roughness (Ra) in the coronal, middle, and apical IRD. The data were analysed by Kruskal–Wallis, Friedman, and Dunn’s tests. All groups showed statistically significant differences (P = 0.007). MO exhibited significantly greater Ra values at the coronal, middle, and apical root levels than OO (P = 0.007, 0.009, and 0.046, respectively). There was no significant change in Ra values at various root levels within each group at P = 0.091, 0.819, 0.819, and 0.549 for the EDTA, saline, MO, and OO groups. Considerable (IRD) surface roughness analysis makes Moringa extract a promising herbal endodontic irrigant alternative to the NaOCl plus EDTA regimen.