Search

Dental rehabilitation of partially or totally edentulous patients with dental implants has become common practice in the last few decades, with reliable long-term results. However, local conditions of edentulous alveolar ridges may be unfavorable for implant placement. Vertically deficient alveolar ridges, in particular, may have insufficient bone volume to hold implants of adequate dimensions, making implant placement difficult or impossible. To correct this situation, a variety of surgical procedures have been proposed, including onlay bone grafts, vertical guided bone regeneration, and alveolar distraction osteogenesis. Distraction osteogenesis is a biologic process of new bone formation between the surfaces of bone segments that are gradually separated by incremental traction. This process is initiated when a traction force is applied to the bone segments and continues as long as the callus tissues are stretched. This traction force, in turn, generates tension within the tissues that connect the bone segments, which stimulates new bone formation parallel to the vector of distraction. The aim of this article is to provide clinicians with the historical background of and biologic basis for the concept of distraction osteogenesis, which can be traced back to the 1800s. Finally, a clinical case is presented to demonstrate a step-by-step application of alveolar distraction osteogenesis as a treatment protocol in a partially edentulous ridge for improvement of esthetics. [ABSTRACT FROM AUTHOR]

Copyright of Acta Reumatológica Portuguesa is the property of Sociedade Portuguesa de Reumatologia 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.)

The article discusses a review of studies on the relationship between bruxism and the risk of dental implant failures. The review analyzed data from the databases PubMed, Cochrane Database of Reviews eCochrane CENTRAL e ADA-Center for Evidence-Based Dentistry. The studies examined the removal of implants due to the loss of osseointegration or implant fractures.

The article describes the case of a 48-year-old male patient with a radicular cyst of the oral cavity. The patient reported pain in the oral cavity. His radiographic exam revealed a radiolucent unilocular lesion with radiopaque contour. He also underwent a computed tomography (CT) scan. The enucleation of the patient's cystic lesion was done.

This review aimed to answer the general question of whether autologous platelet concentrates (APCs, an autologous blood-derivative) can improve the outcome of alveolar bone augmentation. Three clinical scenarios were assessed: horizontal/vertical bone augmentation in combination with implant placement (simultaneous approach), horizontal bone augmentation in a staged approach, and vertical bone augmentation in a staged approach. An electronic literature search strategy was conducted for each review from the outset to July 1st, 2023. The titles and abstracts (when available) of all identified studies were screened and imported into a database. If articles appeared to meet the inclusion criteria or their title and abstract had insufficient data, the full text was obtained to make the final decision. All studies that met the inclusion criteria underwent data extraction. Moreover, the references of the identified papers were screened for additional studies. After title and abstract screening and selection criteria application, 14 clinical studies were included for the qualitative analysis: seven for horizontal/vertical bone augmentation in a simultaneous approach, five for horizontal bone augmentation in a staged approach, and two for vertical bone augmentation in a staged approach. There is scarce literature regarding the added value of APCs in bone augmentation, and most studies had small sample sizes, a lack of standardized protocols, and different outcome variables, which makes comparisons between studies difficult. Out of the 14 studies, four were well-designed randomized clinical trials, where we could find better results for the APCs groups. Most studies, particularly comparative and well-designed studies, demonstrated beneficial and promising results of using APCs in alveolar bone augmentation. However, before high-level evidence-based conclusions can be drawn, more randomized clinical trials must compare the benefits of adding APCs to the gold-standard approach., (© 2024 The Author(s). Periodontology 2000 published by John Wiley & Sons Ltd.)

Background: Oral cancer is a global public health problem. Late diagnosis leads to treatment delays, which consequently result in a worse prognosis and a decrease in the 5-year survival rate. The purpose of this study is to evaluate the oral pathology in a population observed within an oral cancer screening developed in Portugal., Material and Methods: Oral cancer opportunistic screening activities were conducted by the non-profit organization Liga Portuguesa Contra o Cancro ‑ Núcleo Regional do Sul (LPCC-NRS) and data collection occurred between March and December 2022. Participants completed an anonymous questionnaire to collect sociodemographic data and lifestyle habits, followed by a clinical examination of the oral cavity. All individuals classified with oral potentially malignant disorders (OPMD), or suspected lesions of malignant neoplasia were subsequently contacted between January and February 2023 and were questioned about undergoing a biopsy and its respective pathological examination result. Descriptive and analytical statistics were applied., Results: A total of 2674 participants with a mean age of 57 years were screened. Fordyce granules (16.30%) were the most common non-pathological condition, and hairy tongue (11.04%) was the most frequently observed benign lesion. Leukoplakia (43.58%) was the most common oral potentially malignant disorder. Additionally, histological confirmation was obtained for the presence of 4 oral squamous cell carcinomas (OSCC), representing 0.15% of all population screened., Conclusions: Although benign pathology is the most frequently found, oral potentially malignant disorders and suspected malignant lesions were identified in 6.3% of participants in these oral cancer screenings. In this regard, we conclude that the oral cancer screening actions developed by LPCC-NRS were effective in identifying positive cases of OPMDs and oral cancer, using an intraoral visual examination of the oral cavity.

Background/Objectives: Impacted teeth are a common phenomenon, in both young and adult populations, as extensively documented in the literature. This study aims to systematically assess the global prevalence of impacted third molars and to analyze their demographic predictors. Methods: The present review adheres to PRISMA guidelines and includes studies published until December 2023. Three databases (MEDLINE, LILACS, Cochrane) were searched, and studies reporting prevalence rates and demographic predictors of impacted third molars were selected for analysis. A meta-analysis was conducted using a random-effects model to calculate pooled prevalence and assess demographic variations. Results: This review yielded 98 studies involving 183,828 subjects. The pooled prevalence of impacted third molars was 36.9% [95% CI: 33.1-40.7%] per subject and 46.4% [95% CI: 36.7-56.1%] per tooth, with the highest rates in Asia (43.1% [95% CI: 34.6-51.7%]) and the lowest in Europe (24.5% [95% CI: 16.1-33.9%]). An odds ratio of 1.173 [95% CI: 1.021-1.347%] indicated a slightly higher likelihood of third molar impaction among women compared to men, and mandibular third molar impaction was more frequent than maxillary impaction. The meta-regression indicated insufficient consistency for the geographic area to be considered a source of heterogeneity in the prevalence of impacted third molars. Conclusions: The present meta-analysis highlights the substantial prevalence of impacted third molars worldwide and underscores the influence of demographic predictors. These findings may inform region-specific clinical guidelines and preventive approaches for managing impacted third molars.

Background: While titanium implants are widely recognized for their clinical success, zirconia implants have emerged as a metal-free alternative. This study aimed to evaluate the influence of zirconia implant macrogeometry and bone density on primary implant stability. Methods: Two types of zirconia implants were tested-the Neodent ® Zi Ceramic Implant and the Straumann ® PURE Ceramic Implant, that were placed into polyurethane foam blocks mimicking different bone densities (10 PCF, 15 PCF, 20 PCF, 30 PCF, and 40 PCF). Each implant type was inserted and removed multiple times, with primary stability measured using resonance frequency analysis via the Osstell ® Beacon device. Statistical tests, including the Shapiro-Wilk test, t -tests, the Mann-Whitney U test, and the Kruskal-Wallis test, were applied, with significance set at 5% ( p < 0.05). Results: The tapered Neodent ® Zi Ceramic Implant consistently showed higher ISQ values across all foam densities compared to the Straumann ® PURE Ceramic Implant ( p = 0.035). Additionally, lower-density foams exhibited lower stability scores ( p < 0.05). Conclusion: The study concludes that both the macrogeometry of zirconia implants and bone density significantly affect primary implant stability. Specifically, tapered implants demonstrated higher stability than cylindrical designs, suggesting that implant macrogeometry and bone density should be considered for optimal primary stability in clinical settings.

Medication-related osteonecrosis of the jaw (MRONJ) is a rare condition, typically seen in patients receiving antiresorptive or antiangiogenic drugs. This study aims to synthesize reports and case series of MRONJ regarding sociodemographic and clinical characteristics and to evaluate the effectiveness of the treatments applied. Following PRISMA guidelines, a search for case reports and case series was carried out in the PubMed-Medline database until March 2024. A total of 88 articles were included in this review, in a total of 151 cases. The key findings reveal that females were the most affected individuals (71% of the cases) with the average age at diagnosis being 66.27 years with a standard deviation of ±13.03. Stage 2 was the most observed stage, in 43% of cases, and zoledronic acid was the most commonly used drug (32% of cases). The oral route was the most common route of administration, in 26% of cases, with an average administration duration of 60.88 months (standard deviation ± 50.92). The mandible was the most commonly affected anatomical location (in 60% of cases). Amoxicillin + clavulanic acid (875 mg + 125 mg) and chlorhexidine (0.12%) were the most used antibiotics and mouthwash, with 16% and 26% of the cases, respectively. Surgical debridement was the most common surgical procedure, in 32% of cases, while the use of an L-PRF membrane was the most prevalent unconventional treatment, in 21% of cases. This study identified a statistically significant relationship between unconventional treatments and the cure of MRONJ ( p < 0.001), indicating the need for further research to confirm these results.

Vital pulp therapy aims to preserve the vitality of dental pulp exposed due to caries, trauma, or restorative procedures. The aim of the present review was to evaluate the clinical, radiographic, and histological outcomes of different calcium silicate-based cements used in vital pulp therapy for both primary and permanent teeth. The review included 40 randomized controlled trials from a search across PubMed, LILACS, and the Cochrane Collaboration, as well as manual searches and author inquiries according to specific inclusion and exclusion criteria. A critical assessment of studies was conducted, and after data extraction the results were submitted to a quantitative statistical analysis using meta-analysis. The studies, involving 1701 patients and 3168 teeth, compared a total of 18 different calcium silicate-based cements in both dentitions. The qualitative synthesis showed no significant differences in short-term outcomes (up to 6 months) between different calcium silicate-based cements in primary teeth. ProRoot MTA and Biodentine showed similar clinical and radiographic success rates at 6 and 12 months. In permanent teeth, although the global results appeared to be well balanced, ProRoot MTA generally seemed to perform better than other calcium silicate-based cements except for Biodentine, which had comparable or superior results at 6 months. Meta-analyses for selected comparisons showed no significant differences in clinical and radiographic outcomes between ProRoot MTA and Biodentine over follow-up periods. The present review highlights the need for standardized definitions of success and follow-up periods in future studies to better guide clinical decisions. Despite the introduction of new calcium silicate-based cements aiming to address limitations of the original MTA. ProRoot MTA and Biodentine remain the most used and reliable materials for vital pulp therapy, although the results did not deviate that much from the other calcium silicate-based cements. Further long-term studies are required to establish the optimal CSC for each clinical scenario in both dentitions.

Small-sized stainless steel hand files are conventionally employed in root canal treatment procedures for canal scouting and for glide path establishment, owing to their superior flexibility and proficiency in navigating confined spaces. Given the diversity of brands available in the market, there exists potential variability in their physical characteristics, thereby influencing clinical performance. Consequently, this study aims to conduct a comparative analysis of the design, metallurgy, and mechanical characteristics among seven stainless steel hand file brands across ISO sizes 06, 08, and 10. A total of 315 new 25 mm length stainless steel hand files with apical sizes of 0.06, 0.08, and 0.10 from seven distinct brands were included in the study. A meticulous inspection of all instruments was undertaken to identify any structural deformations that might render them ineligible for the study. The design inspection involved the random selection of instruments from each group, which were examined under various microscopes, including a dental operating microscope, optical microscope, and scanning electron microscope. Furthermore, two instruments from each group underwent energy-dispersive X-ray spectroscopy analysis for elemental composition documentation. Mechanical tests were conducted to evaluate the instruments' resistance to lateral deformation (buckling) and their microhardness. Statistical analysis was executed using the nonparametric Mood's median test, with a predetermined significance level of 0.05. Regarding the instruments design, all files exhibited an active blade length ranging from 16 to 17 mm. However, variations were observed in the number of spirals, tip designs, and sizes, with the API K-File notably larger in sizes 0.06 and 0.08 compared to the other instruments. Despite uniform elements composition, differences in geometric features and mechanical properties were evident. Concerning buckling strength, the API K-File demonstrated superior performance across all tested sizes, while the Dentsply ReadySteel, SybronEndo, and Mani K-Files exhibited lower results ( p < 0.05). In microhardness assessments, both the API and Oro K-Files displayed the lowest outcomes, with medians of 531 HVN and 532 HVN, respectively, whereas the SybronEndo K-File exhibited the highest microhardness (657 HVN). Despite similar metallurgical composition, the observed distinctions in geometric features and mechanical properties underscore the impact of the manufacturing process on the characteristics of glide path stainless steel endodontic files. These disparities may ultimately influence their clinical performance.

To establish a glide path, smaller files (up to size 0.15) with tapers of 2% are commonly used as pathfinding files. They pre-shape the root canal space before transitioning to larger taper endodontic instruments, aiming to prevent procedural errors. This study aimed to compare the design, metal wire composition, and mechanical characteristics of seven different ISO size 15 stainless-steel hand files (K-File and C-File+). Ninety-one new stainless-steel ISO 15 K-files were mechanically tested. All files were inspected for deformations before the assessment. Dental operating microscope, scanning electron microscope (SEM), and optical microscope analyses were conducted on four randomly selected instruments from each group, and two instruments per group underwent an energy-dispersive X-ray spectroscopy (EDS) analysis. Buckling mechanical tests were performed using an Instron universal testing machine, and microhardness was assessed using a Vickers hardness tester. The statistical analysis employed the nonparametric Mood's median test, with a significance level set at 0.05. The instrument design analysis unveiled variations in the active blade area length and the number of spirals, while maintaining consistent cross-sections and symmetrical blades. Distinct tip geometries and surface irregularities were observed. While the energy-dispersive X-ray spectroscopy confirmed similar compositions, the buckling strength and microhardness values exhibited variability across for all tested files. Notably, the Dentsply ReadySteel C-File+ recorded the highest buckling value (2.10 N), and the Dentsply ReadySteel K-File exhibited the lowest (1.00 N) ( p < 0.05). Moreover, the Dentsply ReadySteel K-File recorded the highest microhardness value (703 HVN), while the SybronEndo Triple-Flex had the lowest (549 HVN) ( p < 0.05). While similarities in cross-section design and metal wire composition were noted among the files, variations in the number of spirals and mechanical performance were also observed. Thus, all of these factors should be considered when selecting suitable files for an efficient root canal treatment.

Barium titanate (BaTiO 3 ) piezoelectric ceramic may be a potential alternative for promoting osseointegration due to its piezoelectric properties similar to bone electric potentials generated in loading function. In this sense, the aim of this in vitro study was to evaluate the cellular response of human osteoblasts and gingival fibroblasts as well as the impact on S. oralis when in contact with BaTiO 3 functionalized zirconia implant surfaces with piezoelectric properties. Zirconia discs with BaTiO 3 were produced and contact poling (piezo activation) was performed. Osteoblasts (hFOB 1.19), fibroblasts (HGF hTERT) and S. oralis were culture on discs. Cell viability and morphology, cell differentiation markers, bacterial adhesion and growth were evaluated. The present study suggests that zirconia composite surfaces with the addition of piezoelectric BaTiO 3 are not cytotoxic to peri-implant cells. Also, they seem to promote a faster initial osteoblast differentiation. Moreover, these surfaces may inhibit the growth of S. oralis by acting as a bacteriostatic agent over time. Although the piezoelectric properties do not affect the cellular inflammatory profile, they appear to enable the initial adhesion of bacteria, however this is not significant over the entire testing period. Furthermore, the addition of non-poled BaTiO 3 to zirconia may have a potential reduction effect on IL-6 mediated-inflammatory activity in fibroblasts.

The most commonly used material in dental implants and their abutments is titanium. Zirconia is a more aesthetic alternative to titanium abutments; however, it is much harder. There are concerns that zirconia could damage the surface of the implant over time, especially in less stable connections. The aim was to evaluate the wear of implants with different platforms connected to titanium and zirconia abutments. A total of six implants were evaluated, two of each connection type: external hexagon, tri-channel, and conical connections (n = 2). Half of the implants were connected to zirconia abutments, and the other half to titanium abutments (n = 3). The implants were then cyclically loaded. The implant platforms were evaluated by digital superimposing micro CT files and calculating the area of the loss surface (wear). In all the implants, a statistically significant loss of the surface area ( p = 0.028) was observed when comparing the area before and after cyclic loading. The average lost surface area was 0.38 mm 2 with titanium abutments and 0.41 mm 2 with zirconia abutments. The average lost surface area was 0.41 mm 2 with the external hexagon, 0.38 mm 2 with the tri-channel, and 0.40 mm 2 with the conical connection. In conclusion, the cyclic loads induced implant wear. However, neither the type of abutment ( p = 0.700) nor the connection ( p = 0.718) influenced the amount of surface area lost., Competing Interests: The authors declare no conflict of interest.

Objective: To summarize published information regarding malignant tumors with metastasis to the oral cavity., Materials and Methods: This was a systematic review with meta-analysis. An electronic search of Pubmed, Scopus, and Google Scholar databases from inceptions to February 2022 were performed. Only case reports or case series with histopathological results demonstrating metastasis to the oral cavity were included. The main outcomes included demographics, primary site, metastatic site, clinical manifestations, and patient survival. The quality of primary articles was assessed using the Joanna Briggs Institute - University of Adelaide scorecards for case reports and case series. Descriptive analysis and a Kaplan-Meier survival curve were performed., Results: 273 articles were selected (50 case series and 223 case reports), for a total of 950 cases. The mean age was 57.11 years. Males were more affected (57.5%). The most common primary sites in women and men was breast (29.8%), and lung (24.8%), respectively. In ∼1/3 of the cases, oral metastasis preceded tumor dissemination. Jawbones were more affected (56.7%) than soft tissues (37.9%), with the mandible being the most affected site (45.5%), followed by the gingiva (19.9%). The most common clinical manifestation was a mass or nodule. Most radiographic evidence was radiolucency of the jaw (60.6%). 3-year and 5-year survival rates were 14.2 and 10.7%. In the majority of cases, the primary tumor was the first to be diagnosed, while in 30.4%, metastasis was the first sign of the disseminated disease. This can be implied that the oral metastasis should be included in the differential diagnosis list of the oral diseases., Conclusion: Clinicians should be aware of the possibility of, albeit uncommon, oral metastases. Because the extracted data in this review was relatively generalized, the investigators cannot develop the diagnostic clues of oral metastasis, which require further investigations., Competing Interests: Declaration of Competing Interest None to declare., (Copyright © 2022 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

Background: The increased use of dental implants in oral rehabilitation has been followed by the development of new biomaterials as well as improvements in the performance of biomaterials already in use. This triggers the need for appropriate analytical approaches to assess the biological and, ultimately, clinical benefits of these approaches., Aims: To address the role of physical, chemical, mechanical, and biological characteristics in order to determine the critical parameters to improve biological responses and the long-term effectiveness of dental implant surfaces., Data Sources and Methods: Web of Science, MEDLINE and Lilacs databases were searched for the last 30 years in English, Spanish and Portuguese idioms., Results: Chemical composition, wettability, roughness, and topography of dental implant surfaces have all been linked to biological regulation in cell interactions, osseointegration, bone tissue and peri-implant mucosa preservation., Conclusion: Techniques involving subtractive and additive methods, especially those involving laser treatment or embedding of bioactive nanoparticles, have demonstrated promising results. However, the literature is heterogeneous regarding study design and methodology, which limits comparisons between studies and the definition of the critical determinants of optimal cell response.

A multimethod study was conducted to assess the differences between original (PG-OR) and counterfeit (PG-CF) ProGlider instruments regarding design, metallurgical features, and mechanical performance. Seventy PG-OR and PG-CF instruments (n = 35 per group) were evaluated regarding the number of spirals, helical angles, and measuring line position by stereomicroscopy, while blade symmetry, cross-section geometry, tip design, and surface were assessed by scanning electron microscopy. Energy-dispersive X-ray spectroscopy and differential scanning calorimetry were used to identify element ratio and phase transformation temperatures, while cyclic fatigue, torsional, and bending testing were employed to assess their mechanical performance. An unpaired t-test and nonparametric Mann−Whitney U test were used to compare instruments at a significance level of 5%. Similarities were observed in the number of spirals, helical angles, blade symmetry, cross-sectional geometries, and nickel−titanium ratios. Measuring lines were more reliable in the original instrument, while differences were noted in the geometry of the tips (sharper tip for the original and rounded for the counterfeit) and surface finishing with PG-CF presenting more surface irregularities. PG-OR showed significantly more time to fracture (118 s), a higher angle of rotation (440°), and a lower maximum bending load (146.3 gf) (p < 0.05) than PG-CF (p < 0.05); however, maximum torque was similar for both instruments (0.4 N.cm) (p > 0.05). Although the tested instruments had a similar design, the original ProGlider showed superior mechanical behavior. The results of counterfeit ProGlider instruments were unreliable and can be considered unsafe for glide path procedures.

The aim of this study was to evaluate gingival fibroblasts and human osteoblasts' response to textured Nd:YAG laser microgrooves, with different dimensions, on zirconia implant surfaces. A total of 60 zirconia disks (8 mm in diameter and 2 mm in thickness) were produced and divided between four study groups (N = 15): three laser-textured (widths between 125.07 ± 5.29 μm and 45.36 ± 2.37 μm and depth values from 50.54 ± 2.48 μm to 23.01 ± 3.79 μm) and a control group without laser treatment. Human osteoblasts and gingival fibroblasts were cultured on these surfaces for 14 days. FEG-SEM (Field Emission Gun-Scanning Electron Microscope) images showed cellular adhesion at 24 h, with comparable morphology in all samples for both cell types. A similar cell spreading within the grooves and in the space between them was observed. Cell viability increased over time in all study groups; however, no differences were found between them. Additionally, proliferation, ALP (Alkaline phosphatase) activity, collagen type I, osteopontin and interleukin levels were not significantly different between any of the study groups for any of the cell types. Analysis of variance to compare parameters effect did not reveal statistically significant differences when comparing all groups in the different tests performed. The results obtained revealed similar cell behavior based on cell viability and differentiation on different microtopographic laser grooves, compared to a microtopography only established by sandblasting and acid-etching protocol, the reference surface treatment on zirconia dental implants.

Two type of cells representing periodontal hard tissues (osteoblasts) and soft tissues (fibroblasts) were evaluated in response to microgroove-milled zirconia surfaces. A total of 90 zirconia discs were randomly assigned to four width-standardized milling microgroove-textured groups and a control group without grooves (UT). The sandblast and acid-etch protocol were applied to all samples. Both cell lines were cultured on zirconia discs from 1 day up to 14 days. Cell morphology and adhesion were evaluated after 1 day of culturing. Cell viability and proliferation of the cells were measured. Alkaline phosphatase activity, collagen I, osteopontin, interleukin 1β and interleukin 8 secretions were assessed at predefined times. The results obtained were presented in the form of bar graphs as means and standard deviations. Multi comparisons between groups were evaluated using two-away ANOVA or Mann−Whitney tests, and a p-value < 0.05 was established. Group comparisons with regard to cell viability, proliferation and secretion of collagen I, interleukin-1β and interleukin 8 revealed no statistically significant differences. The alkaline phosphatase activity and osteopontin secretion were significantly higher in the group with a large groove compared to the small one and the control group. Nevertheless, the viability of gingival and bone cells did not appear to be affected by the milled microgroove texture compared to the conventional sandblasted and acid-etched texture, but they seem to influence osteoblasts’ cellular differentiation.

Background: The aim of this study was to comprehensively evaluate the cyclic fatigue strength of ProGlider, Edge Glide Path, and R-Pilot instruments., Methods: Sixty-three instruments were submitted to a multimethod evaluation. Their design was analyzed by stereomicroscopy and scanning electron microscopy, including the number of blades, helical angle means, cross-sectional design, surface finishing, and symmetry. Energy-dispersive X-ray spectroscopy was used determine the nickel/titanium elements ratio, and differential scanning calorimetry determined the instruments' phase transformation temperatures. The cyclic fatigue tests were conducted in an artificial canal with a 6 mm radius and 86 degrees of curvature. The Mood's median test and one-way ANOVA were used to determine differences, with the significance level set at 0.05., Results: The ProGlider presented the highest number of blades ( n = 21), while R-Pilot had the highest helical angles (26.4°). Differences were noted in the instruments' cross-sections and surface finishing. The ProGlider and R-Pilot showed some similarities regarding the phase transformation temperatures but differed from the Edge Glide Path. All alloys showed an almost equiatomic nickel/titanium ratio. The R-Pilot instruments showed a significantly higher ( p < 0.05) time to fracture than both the other files., Conclusion: Reciprocating R-Pilot instruments showed a higher cyclic fatigue time to fracture than the ProGlider and Edge Glide Path rotary files.

The use of zirconia as an alternative biomaterial for titanium implants has been increasing due to its biocompatibility, favorable aesthetic features, less potential for early plaque accumulation and mechanical properties. Despite the developed efforts, strategies to promote an effective osseointegration are still enough. In this sense and combining the silica properties to improve bone formation with the micropatterning guidance characteristics, silica coatings with micropatterns were designed and evaluated regarding their hydrophilicity and integrity through resistance to scratch and friction tests against femoral bone plates (simulating implant insertion). A combined sol-gel and soft-lithography techniques were used to produce silica coatings onto zirconia substrates and different techniques were used to characterize the micropatterned silica coatings. The results revealed that the production of lines and pillars micropatterns increases the surface roughness (Ra values) and improves the surface strength adhesion. Through the scratch test, it was possible to verify that the integrity and topography characteristics of all micropatterned coatings were not significantly affected after the friction test meaning that their function is not compromised after implant insertion. Additionally, the lines micropattern was the one that presented the highest hydrophilicity for distilled water, thus being a promising surface to promote improved osseointegration. The combined use of different surface micropatterns could potentially be used to guide bone apposition and avoiding peri-implantitis., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objectives: To address the following question: "Is the timing of implant placement and/or loading influencing the esthetic outcomes of implant-supported single crowns?", Material and Methods: A literature screening was performed in four electronic databases until June 2020. Randomized controlled clinical trials with a minimum of 10 patients and 1 year of follow-up and reporting on dimensional changes of the peri-implant mucosa (midfacial recession, papilla level) and esthetic indexes were included. Cochrane Risk of Bias Tool was used, and comparable trials were subjected to meta-analyses., Results: Out of 8549 articles, 72 full-text articles were assessed for eligibility and 18 were included. Nine trials evaluated the timing of implant placement, and nine trials evaluated the timing of loading. The included trials comparing immediate implant placement to delayed implant placement evaluating the midfacial recession reported heterogeneous findings. No differences were found at 1 and 2-years, when comparing midfacial recession and papilla level between immediate and early implant placement. In immediate and delayed implant placement, when comparing conventional and immediate loading, the midfacial mucosal margin change was not statistically significant at the 1-year follow-up. When evaluating the timing of implant placement and/or loading the included trials found no differences in the Pink Esthetic score, White Esthetic score, and Papilla Index between groups., Conclusions: Both immediate and early implant placement protocols presented stable treatment results in terms of esthetic outcomes at the 1-, 2-, and 10-years follow-up. Loading protocols did not seem to influence esthetic outcomes in short- and medium-term follow-ups., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

This retrospective study evaluated the survival rate of short, sandblasted acid-etched surfaced implants with 6 and 8 mm lengths with at least 120 days of follow-up. Data concerning patient, implant and surgery characteristics were retrieved from clinical records. Sandblasted and acid-etched (SLA)-surfaced tissue-level 6 mm (TL6) or 8 mm (TL8) implants or bone-level tapered 8 mm (BLT8) implants were used. Absolute and relative frequency distributions were calculated for qualitative variables and mean values and standard deviations for quantitative variables. A Cox regression model was performed to verify whether type, length and/or width influence the implant survival. The cumulative implant survival rate was assessed by time-to-event analyses (Kaplan-Meier estimator). In all, 513 patients with a mean age of 58.00 ± 12.44 years received 1008 dental implants with a mean follow-up of 21.57 ± 10.77 months. Most implants (78.17%) presented a 4.1 mm diameter, and the most frequent indication was a partially edentulous arch (44.15%). The most frequent locations were the posterior mandible (53.97%) and the posterior maxilla (31.55%). No significant differences were found in survival rates between groups of type, length and width of implant with the cumulative rate being 97.7% ± 0.5%. Within the limitations of this study, the evaluated short implants are a predictable option with high survival rates during the follow-up without statistical differences between the appraised types, lengths and widths.

Objective: The purpose of this systematic review was to assess the influence of population demographic characteristics on the prevalence of a second canal in mandibular anterior teeth., Design: Four electronic databases and five peer-reviewed journals were searched from May 2018 to September 2019 for prevalence studies using cone-beam computed tomographic imaging on second canal morphology in mandibular anterior teeth. The identified studies were subjected to a hand search of bibliographic references followed by contact with the authors. Full text analysis and critical appraisal (JBI) was undertaken on 40 papers by 2 evaluators. Sixteen studies were included into a meta-analysis. Forest plots with proportion and odds ratios with a 95% confidence interval were calculated. Meta-regression was performed in order to identify possible sources of heterogeneity., Results: The 16 selected studies presented an average JBI score of 77.7% and revealed data from 40,784 mandibular anterior teeth (14,278 central incisors, 14,433 lateral incisors, and 12,073 canines). The overall prevalence of a second canal for central incisors, lateral incisors and canines was 20.4% (15.0%-25.7% CI 95%), 25.3% (20.0%-30.7% CI 95%) and 5.9% (4.1%-7.7% CI 95%), respectively. Males showed significantly higher odds of having a second canal for both incisors (p < 0.05). East Asia studies presented lower proportions of a second canal in mandibular anterior teeth (p < 0.05)., Conclusions: The overall prevalence of a second canal in the mandibular central and lateral incisors and canines was 20.4%, 25.3% and 5.9%, respectively. Meta-analysis calculation revealed gender and patient geographic origin as possible confounding factors of the proportion outcomes., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Introduction: The purpose of this study was to perform a quality assessment and provide a scientific-based checklist for prevalence studies on root and root canal anatomy by appraising the methodological quality of in vivo studies using cone-beam computed tomographic (CBCT) imaging as the assessment tool., Methods: A systematic assessment of the literature was conducted, and 211 studies were selected and submitted to a methodological evaluation. Data were grouped into categories such as journal impact factor, open access availability, language, study origin, journal publisher, sample size, and CBCT settings. Interrater agreement was calculated by applying the Holsti method and Cohen kappa. The Kruskal-Wallis test and Pearson correlation coefficient were undertaken to assess the different variables (α = 0.05)., Results: The included studies (N = 211) reported data on 247,616 teeth from 41 countries. The maxillary first molar was the most studied tooth (n = 69) and the second mesiobuccal canal the most investigated anatomic feature. The highest scores were associated with high-impact journals (r = 0.482, P < .05), large sample sizes (r = 0.374, P < .05), non-open access availability (P < .05), and English-based language (P < .05), but geographic region and journal publisher also had an impact on quality scores. The identified methodological gaps were used to formulate a scientific-based checklist for this type of study., Conclusions: Although a small improvement in the global quality of the studies was observed over the years, only less than half of the studies correctly addressed the participant recruitment and frame and had an adequate sample size or provided sufficient CBCT imaging settings. The proposed checklist highlights the most pertinent points to guide researchers throughout the experimental design and the implementation of epidemiological cross-sectional studies of this nature., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to perform a systematic review of prevalence studies to determine the rate of malignant transformation of oral leukoplakia and assess the influence of demographic factors (age, gender, and geographic region) on the overall transformation rate., Study Design: A search was conducted for publications until July 2019 in 4 electronic databases and peer-reviewed journals. A manual search was performed on the bibliographies of the collected articles, and the authors were contacted for additional information. This study was previously registered with the trial number CRD42019126909 and study quality assessed through established methods. The results were expressed by means of proportions or odds ratios with a 95% confidence interval. Meta-regression was undertaken to evaluate possible sources of heterogeneity, and funnel plot visual analysis was performed to assess publication bias., Results: The 34 observational epidemiologic studies included reported data on 26,209 patients with oral leukoplakia from 18 different countries. Meta-analysis of 32 studies (23,489 patients) presented an estimated overall mean proportion of malignant transformation rate of 9.70% (7.80-11.70) (I 2  = 98.66%; τ 2 < 0.001; χ 2  = 23.18; degrees of freedom [df] = 31). When comparing genders, the odds ratio favored males with 0.622 (0.468-0.826) (I 2  = 29.77%; τ 2  = 0.089; χ 2  = 22.78; df = 16)., Conclusions: Within the limitations of the included studies in this systematic review, the results suggest that the malignant transformation rate was dependent on demographic factors and follow-up time. Future studies should include the development of guidelines to standardize the methodology for long-term follow-up assessment, thus reducing the risk of bias., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objective: To assess the influence of cone-beam computed tomographic (CBCT) voxel size and population demographic aspects (age, gender and geographic region) on the prevalence of the second mesiobuccal root canal (MB2) in maxillary first and second molars., Design: Prevalence studies using CBCT technology on MB2 canal were searched between May and September 2019. The protocol was registered in PROSPERO. Four electronic databases and 5 peer-reviewed endodontic journals were screened. Authors were contacted and bibliographic references hand-searched. Eighty three studies were submitted to full text analysis and scientific merit evaluation by 2 evaluators using Joanna Briggs Institute Critical Appraisal tool. Twenty six studies were finally pooled into a meta-analysis. Forest plots with a 95% confidence interval were undertaken. Meta-regression was used to identify possible sources of heterogeneity and funnel plot visual analysis to assess publication bias., Results: The 26 studies reported anatomical data from the mesiobuccal root of 15,285 first molars and 8,641 second molars. Pooled prevalence of MB2 canal was higher in maxillary first molar (69.6%; 64.5%-74.8%) than in second molars (39.0%; 31.1%-46.9%) (p < 0.05). A significantly higher prevalence odds of having MB2 canal was detected in males (p < 0.05). Meta-regression excluded gender, age and voxel size as a source variance, but identified tooth group and geographic region as possible sources of heterogeneity., Conclusion: MB2 canal prevalence was significantly higher in maxillary first molars. Males showed higher odds of having MB2 canal than females. Geographic region seemed to influence MB2 prevalence outcome. Knowing these preoperative factors would help to anticipate MB2 morphologies in clinics., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Management of severe worn dentition in patients with bruxism is challenging as a result of the loss of tooth structure and occlusal vertical dimension, temporomandibular implications, tooth hypersensitivity, and masticatory or aesthetic impairment. This case describes the 4-year follow-up clinical evaluation of a full mouth tooth-supported rehabilitation made on a 66-year-old man with bruxism and tooth wear, with aesthetic complaints and compromised masticatory function. The prosthetic treatment was planned with a digital smile design and a mock-up technique for an aesthetic and minimally invasive approach using lithium disilicate pressed and layered veneers on anterior teeth, posterior CAD/CAM lithium disilicate overlays with facial coverage, and CAD/CAM monolithic zirconia crowns with facial feldspathic ceramic on maxillary and mandibular canines and first molars in order to ensure the occlusal stability at the increased occlusal vertical dimension. After 4 years of function, no complications were registered. The choice of an appropriate material for the rehabilitation of these patients is essential to improve treatment prognosis and should be guided by mechanical and aesthetical properties. The use of four-point occlusal stabilization with CAD/CAM high strength monolithic zirconia crowns combined with ceramic veneers and overlays appears to be a reliable treatment option that enhances aesthetics and minimizes the occurrence of ceramic fractures, ensuring the treatment prognosis and predictability., Competing Interests: The authors declare that they have no conflicts of interest.

This report describes a clinical and laboratory protocol used in the fabrication of a removable partial dental prosthesis with a digital workflow in a 73-year-old patient. The metal framework was produced with a selective laser melting technique. For quality assurance and discrepancy analysis, the framework was superimposed and compared to the respective digital design file, and the printed model was also compared to the digital impression and rendered as a 3D colour map. Differences were detected in the framework on the clasp of tooth 17 (upper right second molar) and on the printed model on the interproximal surfaces of the abutments, particularly on tooth 17 and palatine area. The use of this digital workflow allowed for the achievement of an removable partial dental prosthesis with a good fit and occlusion with minimal adjustments, with the reduction of both clinical and laboratory time. Further studies are needed to gain a better understanding of these techniques., Competing Interests: Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Introduction: In the literature, several prevalence studies on root canal anatomy using cone-beam computed tomographic technology are currently available although their results remain disperse. This systematic review aimed to appraise and combine, under strict criteria conditions, selected prevalence studies in order to comprehend the distribution of root canal configuration types among different populations., Methods: This systematic review was registered in PROSPERO. Six electronic databases were accessed, and the studies were selected according to a predefined inclusion/exclusion criteria. References of the collected studies and 3 peer-reviewed endodontic journals were hand searched. The authors of the selected studies were contacted for additional information. All eligible studies were submitted to a scientific merit evaluation by 2 evaluators independently, who also reached a final consensus for each study score using the Joanna Briggs Institute Critical Appraisal tool for prevalence studies., Results: Fifty-two studies from 28 different countries including 102,610 teeth and presenting a Joanna Briggs Institute Critical Appraisal tool average score of 80.5% were included in this review. Overall, results showed a wide prevalence range of the second mesiobuccal canal in maxillary first and second molars but also a high prevalence of single-rooted configuration in maxillary first premolars and mandibular second molars and 3-rooted morphology in the mandibular first molar of Asian populations., Conclusions: The included studies showed a global tendency for a particular morphology in some groups of teeth, whereas others showed diversity in specific anatomic types among different populations., (Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

The aim of this study was to evaluate and compare the quality of systematic reviews of vertical bone regeneration techniques, using two quality-assessment tools (AMSTAR and ROBIS). An electronic literature search was conducted to identify systematic reviews or meta-analyses that would evaluate at least one of the following outcomes: implant survival, success rates, complications or bone gain after vertical ridge augmentation. Methodological quality assessment was performed by two independent evaluators. Results were compared between reviewers, and reliability measures were calculated using the Holsti's method ® and Cohen's kappa. Seventeen systematic reviews were included, of which seven presented meta-analysis. Mean ±95% confidence interval AMSTAR score was 6.35 [4.74;7.97], with higher scores being correlated with a smaller risk of bias (Pearson's correlation coefficient=-0.84; P<0.01). Cohen's inter-examiner kappa showed substantial agreement for both checklists. From the available evidence, we ascertained that, regardless of the technique used, it is possible to obtain vertical bone gains. Implant success in regenerated areas was similar to implants placed in pristine bone with results equating between 61.5% and 100% with guided bone regeneration being considered the most predictable technique regarding bone stability, while distraction osteogenesis achieved the biggest bone gains with the highest risk of possible complications., (Copyright © 2018 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Objectives: To evaluate the performance of two types of zirconia frameworks., Material and Methods: From 2014 to 2016, in a prospective clinical trial, 150 patients were rehabilitated with 83 and 110 implant-supported, screw-retained, full-arch ceramic-veneered zirconia (PVZ) rehabilitations and monolithic zirconia with porcelain veneering limited to buccal (MZ) rehabilitations, respectively. Patients were consecutively enlisted according to pre-defined inclusion criteria and evaluated on 4 months intervals. A Kaplan-Meier estimator was adopted, and the log-rank test and Wilcoxon test used to test differences in survival and successful function in the two different groups., Results: The average follow-up time (±SD) and implant success rate was 608.80 ± 172.52 days with 99.53% implant success for the PVZ group and 552.63 ± 197.57 days with 99.83% success for the MZ group. According to the Kaplan-Meier estimator, the mean cumulative survival rate at the 2-year follow-up for framework fracture, major chipping, minor chipping, or any of the former combined to occur was 0.99, 0.95, 0.93 and 0.85 for the PVZ group (n = 18) and 0.99, 0.95, 0.95 and 0.89 for the MZ group (n = 15). No significant differences were found between the two groups., Conclusions: Results suggest zirconia as a suitable material for frameworks in full-arch implant-supported rehabilitations. Both groups presented a low incidence of technical complications. When comparing the two different designs, the MZ group presented a lower technical complication rate, thus presenting itself as a viable alternative for full-arch implant-supported rehabilitations. Further clinical studies with longer follow-ups (5 years) should be performed to evaluate the long-term stability of such rehabilitations., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: This prospective clinical study evaluated the success rate of indirect composite resin cuspal coverage on endodontically treated molars and premolars and the survival rate of the restored teeth., Materials and Methods: One hundred fifty endodontically treated teeth were restored with total resin cuspal coverage and randomly selected for the study. Patients were recalled after 2 to 5 years for clinical evaluation. Data were subjected to standard tests of statistical correlations using Spearman test., Results: Out of the 150 teeth, 84 were molars and 66 were premolars. Of these teeth, 58.7% had mesio-occlusal-distal (MOD) cavities, 20.7% had mesio-occlusal (MO), and 20.7% had occlusal-distal (OD). A build-up procedure was performed in 51.3% of the teeth, and buccal veneer composite resins were placed at the margins of 96.7% of the teeth. Out of the 150 teeth, 30 (20%) presented margin discoloration, 3 teeth (2%) had restoration reparable fractures, 2 teeth (1.3%) had restoration irreparable fractures, and 1 tooth (0.7%) exhibited secondary recurrent caries. The opposing arch that occluded with the treated teeth presented 58% natural teeth (no restoration material), 26.7% ceramic crowns, and 15.3% implant-supported ceramic crowns. Statistically significant differences (p = 0.018) between irreparable restoration fractures and the type of support material present in the opposing arch were found., Conclusions: In a period of up to 5 years, the resin cuspal coverage of endodontic treated teeth had a success rate of 96%, while the tooth survival rate was 100%. The type of support material on the opposing arch may influence the longevity of the restoration of endodontically treated teeth., (© 2016 by the American College of Prosthodontists.)

Objective: Titanium is the most commonly used material to manufacture dental implants and abutments. Recently, zirconia abutments have been manufactured with better aesthetic properties. However, zirconia abutments are harder than titanium implants; therefore, they could wear the implant surface. Therefore, this article aims to describe a sphere-plane system that can be used to assess the wear that different abutment materials cause in the titanium of dental implants when submitted to cyclic loading. This method can be used to simulate the oral cavity, where the abutment (sphere) applies loads onto the implant (titanium plane). The spheres were made of different materials (titanium and zirconia), and the specimens were loaded for 4,000,000 cycles. The scar size and area on titanium planes were measured with stereoscopic images and analysed through profilometry., Results: The wear of titanium planes was similar when tested against zirconia or titanium spheres. The sphere-plane system is a method that can be used to evaluate and quantify the wear of the titanium of dental implants, and compared with methods that use real implants, this system is simpler and less expensive. This method could facilitate further research to evaluate the wear of titanium against different materials and under different testing conditions.

The aim of this study was to analyze the osteogenic cell behavior on the surface of novel functionally graded titanium-based composites containing bioactive ceramics. Titanium grade V discs (8 × 3 mm) embedding gradual content of hydroxyapatite (TiAlV-HA) or beta-tricalcium phosphate (TiAlV-βTCP) were produced by hot-pressing technique. Titanium-ceramic composite discs and Ti grade V (control group) were placed in contact with human osteoblast culture assays. The morphology and adhesion of osteoblasts were inspected by field emission guns scanning electron microscopy (FEGSEM) while cell viability was assessed by fluorometric method. Alkaline phosphatase (ALP) activity and fluorescent microscopic analyses were used to evaluate mineralization on the test and control discs. FEGSEM images showed cells adhered to Ti6Al4V-ceramic and Ti6Al4V surfaces over a period of 24 h, and therefore, an intense proliferation of osteoblasts and spreading cells was noticed for 7 days. Cell viability increased with time on all the surfaces although TiAlV-βTCP revealed significant higher percentage of cell viability than that recorded for TiAlV-HA (p < 0.01). TiAlV-βTCP also showed the highest hydrophilic character. ALP levels increased on the Ti6Al4V-ceramic surfaces when compared to the control group. Also, a qualitative analysis of mineralization evidenced an increase in mineral content on TiAlV-HA or TiAlV-βTCP groups. Novel functionally graded composites based on Ti grade V and hydroxyapatite or βTCP showed a higher bioactivity in presence of osteoblasts than that recorded on Ti grade V. Also, such functionally graded materials can prevent risks of failures by detachment of bioactive ceramic materials during implant placement. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1923-1931, 2018., (© 2018 Wiley Periodicals, Inc.)