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Aim: To investigate whether silibinin impacts diabetic periodontitis (DP) via mitochondrial regulation. Materials and Methods: In vivo, rats were divided into control, diabetes, DP and DP combined with silibinin groups. Diabetes and periodontitis were induced by streptozocin and silk ligation, respectively. Bone turnover was evaluated by microcomputed tomography, histology and immunohistochemistry. In vitro, human periodontal ligament cells (hPDLCs) were exposed to hydrogen peroxide (H2O2) with or without silibinin. Osteogenic function was analysed by Alizarin Red and alkaline phosphatase staining. Mitochondrial function and biogenesis were investigated by mitochondrial imaging assays and quantitative polymerase chain reaction. Activator and lentivirus-mediated knockdown of peroxisome proliferator-activated receptor gamma-coactivator 1-alpha (PGC-1α), a critical regulator of mitochondria biogenesis, was used to explore the mitochondrial mechanisms. Results: Silibinin attenuated periodontal destruction and mitochondrial dysfunction and enhanced mitochondrial biogenesis and PGC-1α expression in rats with DP. Meanwhile, silibinin promoted cell proliferation, osteogenesis and mitochondrial biogenesis and increased the PGC-1α level in hPDLCs exposed to H2O2. Silibinin also protected PGC-1α from proteolysis in hPDLCs. Furthermore, both silibinin and activator of PGC-1α ameliorated cellular injury and mitochondrial abnormalities in hPDLCs, while knockdown of PGC-1α abolished the beneficial effect of silibinin. Conclusions: Silibinin attenuated DP through the promotion of PGC-1α-dependent mitochondrial biogenesis.

In this case report, we describe the treatment of a patient referred to our clinic with a hopeless tooth 21 with an attached pontic. The aim of this case report was to, first, describe the advantages and disadvantages of gaining soft tissue with a self-inflating soft tissue expander before performing a bone augmentation procedure in implant dentistry in the esthetic zone. Second, we describe how an amalgam tattoo, caused by a previously performed apicoectomy that made the extension of the raised flap to cover the augmented site esthetically undesirable, was removed. Two silicone enveloped Osmed hydrogel self-inflating soft tissue expanders were placed submucosally on the right- and left-hand side of the amalgam tattoo. One of these two perforated the overlaying mucosa after 24 days. Both tissue expanders were removed, the amalgam tattoo was excided, the site augmented, and an implant with a crown and a pontic was placed.

Purpose: To compare the fit and clinical performance of screw-retained monolithic zirconia implant fixed dental prostheses (FDPs) fabricated based on either intraoral optical scanning (IOS) or conventional impressions. Materials and Methods: Patients with two posterior tissue-level implants (Regular Neck, Straumann) replacing two or three adjacent teeth were recruited. Impressions were taken with both IOS (True Definition Scanner, 3M Espe) and a conventional (polyether) pick-up impression. Double-blind randomization was performed after impression-taking, and patients were to receive an FDP based on either the digital or the conventional impression. The fit was evaluated, and the time required for adjustments was recorded. Additionally, survival and technical complication rates with a follow-up of 1 year were documented. Results: A total of 38 patients requiring 45 FDPs were included: 24 FDPs in the test (IOS) and 21 in the control (conventional) group. The average adjustment time was 6.92 minutes (SD: ± 10.84; range: 0 to 49) for digital vs 12.38 minutes (SD: ± 14.52, range: 0 to 54) for conventional impressions (P= .090). A proper fit (no adjustments) was achieved in 33.3% of the digital and 28.6% of the conventional group. Forty-two FDPs could be placed within the two planned appointments, and 3 FDPs exhibited an unacceptable fit and required an extra appointment. Eight technical complications occurred during the first year of function. The overall restoration survival rate was 100%. Conclusion: The clinical fit of CAD/CAM FDPs based on digital impressions is comparable to conventional impressions. Screw-retained monolithic zirconia FDPs on Ti-base abutments show low major complication and 100% survival rates in the short term. Int J Prosthodont 2021;34:733–743. doi: 10.11607/ijp.7074

Aim To study the time and costs involved with computer-assisted versus non-computer-assisted implant planning and placement. Material and methods Based on the PICO question, "In patients receiving dental implants, is computer-assisted implant planning and surgery (CAIPS) compared to non-computer-assisted implant planning and surgery (non-CAIPS) beneficial in terms of treatment related costs and time involved?", a search path was created to perform an electronic search in the databases PubMed, PubMed Central, EMBASE, and Cochrane. The publication period of eligible publications extended from 01.01.2005 to 04.05.2020. Four independent reviewers reviewed the literature to identify studies that met the eligibility inclusion criteria. A further manual search of articles was performed, and gray literature was excluded. Corresponding authors of potentially eligible manuscripts were contacted for further information. Results Of the 1354 retrieved titles after the search were screened. Thirty-one articles have been identified to read the full text, resulting in four articles to be analyzed for the present review all of which were RCTs. In total, 182 partially and completely edentulous patients were treated with 416 implants following either non-computer-assisted or computer-assisted implant planning and surgery to determine the duration of the single working steps and the financial aspects of the different procedures. Conclusions When evaluating the time and costs involved with the diagnostic and planning procedures in computer-assisted implant planning and surgery workflow protocols, one can summarize that these are higher than in the non-computer-assisted workflow protocols. The time involved with the procedures appears to be the driving factor when it comes to economic considerations. On the basis of the conclusions, also the time for the prosthetic restoration should be taken into account.

6. EAO Consensus Conference 2021, online, 11 Feb 2021 - 12 Feb 2021; Clinical oral implants research 32(S21), 336-341 (2021). doi:10.1111/clr.13797 special issue: "Special Issue: The 6th EAO Consensus Conference 2021 / edited by: Irena Sailer, Björn Klinge, Henning Schliephake", Published by Wiley-Blackwell, Oxford

To report on the follow-up of two earlier published RCTs on the performance of screw-retained monolithic zirconia restorations on Ti-base abutments based on intraoral optical scanning or conventional impressions.A total of 54 patients receiving 89 restorations (44 single crowns [SC]), 21 splinted crowns [2-FDP], and 24 three-unit fixed partial dentures (3-FDP)] were included in the 1- to 3-year follow-up period. The restoration survival and technical complications were documented.A total of 50 patients with 84 restorations completed the 3-year follow-up. One 3-FDP from the IOS group was lost. This resulted in survival rates of 97.9% for the test and 100% for the control restorations and an overall survival rate of screw-retained monolithic zirconia restorations on implants of 98.8% after 3 years. There was no statistically significant survival difference between the test and control groups (P = .362). When evaluated separately, a 100% survival rate for SCs and 97.7% rate for 2-FDPs was reported. One decementation and three occurrences of screw loosening occurred over the 1- to 3-year follow-up. The multiple-implant restorations showed higher (23.3%) complication rates at the restoration level than the SCs (4.9%) after 3 years of function (P = .026).Screw-retained monolithic zirconia restorations on Ti-base abutments show promising survival rates after 3 years of function. Restorative complications of screw-retained monolithic zirconia restorations on Ti-base abutments are more likely to happen in the first year of function and are more common in multiple-implant restorations than solitary crowns. The impression (IOS or conventional) does not seem to influence these results.

OBJECTIVES To report a summary of published patient-reported esthetic outcome measures (PROMs) of implant-supported single crowns (SCs) compared with those of tooth-supported SCs. MATERIALS AND METHODS Cochrane, Medline (PubMed), and EMBASE database search was performed by three reviewers on reports with patient-reported esthetic outcomes of tooth- and implant-supported SCs. Clinical studies with at least 12 months of mean follow-up period and a minimum of 10 patients, and English, French, or German reports were included. To compare the subgroups, for aggregate-level data, random-effects meta-regression was used. RESULTS Two thousand fifteen titles were identified (initial search) and screened independently concluding 53 full-text articles to include in data extraction. Twenty-two studies with 29 study cohorts were included. Patients were satisfied with the esthetics of implant- and tooth- supported crowns Mean visual analogue scale (VAS) value from the PROMs data of 1270 implant-supported SCs evaluated by 1051 patients was 89.6% (80.0%-94.1%). The mean VAS value of patients (n = 201), who evaluated the esthetic outcome of 486 tooth-supported SCs was 94.4% (92.3%-96.0%). VAS scores of patients regarding their perception of esthetics did not show any difference among different crown materials or type of implant used. The patients' perception of esthetics focusing on SC had a tendency to be higher when the crowns were supported by teeth, however, no statistical difference was found when compared with implant-supported crowns (p = 0.067). CONCLUSIONS Patient perception of esthetics in SCs was not affected by the type of support, crown material, implant, and presence of provisional crown for both implant- and tooth-supported SCs. CLINICAL SIGNIFICANCE Despite that patient's expectations are increasing overall Patients are satisfied with with esthetic outcome of implant- and tooth-supported crowns.

© 2021 by Quintessence Publishing Co IncPurpose: There is a substantial need to perform studies to evaluate crestal bone loss (CBL) and implant success when using a newly introduced low-speed drilling protocol. Therefore, this study aimed to evaluate the mean CBL and implant success rate by placing implants utilizing two drilling protocols, ie, standard and low-speed drilling protocols. Materials and Methods: A randomized controlled clinical trial was carried out in patients who required dental implants to restore their esthetics and function. The patients were recruited from a university hospital (Academic Centre for Dentistry Amsterdam [ACTA], the Netherlands). Based on the inclusion criteria, patients were randomized to two study groups: (1) control group, standard drilling protocol; and (2) test group, low-speed drilling protocol without saline irrigation. The mean CBL and the implant success rate were evaluated after 12 months of implant placement. Results: Twenty-three patients (15 men and 8 women with a mean age of 57.5 ± 10.7 years) contributed to the study. Forty Camlog screw-line implants were placed (20 implants per study group). After 12 months of implant placement, the mean CBL of implants placed with the standard protocol and the low-speed protocol was 0.206 ± 0.251 mm and 0.196 ± 0.178 mm, respectively. No statistically significant difference could be recorded among both groups (P =.885). Concerning implants placed in the maxilla, the standard drilling group and low-speed drilling group showed a mean CBL of 0.252 ± 0.175 mm and 0.251 ± 0.175 mm, respectively, compared with 0.173 ± 0.210 mm and 0.141 ± 0.172 mm in the mandible, with no significant difference. The success rate of dental implants at 12 months was 95% in the control group and 90% in the test group. Conclusion: Within the limitations of this study, it can be concluded that implants placed with the low-speed drilling protocol without saline irrigation exhibited a similar CBL compared with implants placed with the standard drilling protocol. However, a higher success rate was recorded especially in type 1–quality bone for the control group compared with the test group. Further randomized clinical trials with greater sample sizes and extended follow-up times should be performed to obtain stronger evidence and a better understanding of the influence of drilling speed on mean CBL and long-term implant success

© 2020 Editorial Council for the Journal of Prosthetic DentistryStatement of problem: Vertical eruption of teeth adjacent to an implant has been reported clinically and might affect the esthetic outcome over time. The prevalence of the problem is unclear. Purpose: The purpose of this prospective clinical trial was to evaluate the vertical eruption of anterior maxillary teeth adjacent to single-implant crowns after a 3-year follow-up period. Material and methods: Thirty single dental implants were inserted in maxillary anterior sites including the first premolar. The mean age of the participants at implant-supported crown insertion was 48.4 years (range 23 to 79 years). Each implant was restored with a 1-piece screw-retained ceramic single crown. The vertical changes of 60 adjacent anterior maxillary teeth were evaluated from periapical radiographs and casts at baseline, 6, 12, and 36 months. Results: A global ANOVA test showed statistically significant differences for the outcomes of the distance-implant platform and cement-enamel junction (DPC) (P

Este artículo se encuentra disponible en la siguiente URL: https://www.sciencedirect.com/science/article/pii/S0300571222001518 En este artículo de investigación también participan: Mutlu Özcan, Frauke Müller y Daniel Wismeijer. Objective: The study aimed to quantitatively evaluate the elution of methylmethacrylate from CAD-CAM manufactured removable complete dentures (RCDs) using high performance liquid chromatography (HPLC). Methods: Thirty-two RCDs were manufactured following either the CNC-milling (Milled: n=8) or the 3D-printing (n=24) protocols. The 3D-printed dentures were further categorized into three groups based on their postproduction rinsing cycles [Extended wash cycle (EWC), Standard wash cycle (SWC), and SWC with an additional Dur´econ coating (SWC2)]. HPLC was used to evaluate the methylmethacrylate concentrations (MMCs) eluted from the dentures in each group for different time periods (1, 2, 4, 8, and 24 hours). Mean and standard deviations were calculated for the MMCs; data was verified for normal distribution, ANOVA and post hoc tests were applied for statistical analyses (⍺=0.05). Results: The HPLC revealed that all the denture groups recorded some amounts of MMCs, with significant differences [F (3, 31) = 23.646, p

Objective: The aim of this randomized multicenter clinical trial was to evaluate and compare the performance of anterior all-ceramic implant crowns based either on prefabricated zirconia abutments veneered with pressed ceramics or on CAD/CAM zirconia abutments veneered with the hand build-up technique. The null hypothesis was that there is no statistically significant difference between the two study groups. Material and methods: Forty implants were inserted in sites 14–24 (World Dental Federation [FDI]) in two centers, the Universities of Bern and Geneva, Switzerland. Twenty patients each were randomized into either Group A and restored with one-piece single crown made of a prefabricated zirconia abutment with pressed ceramic, or Group B using an individualized CAD/CAM zirconia abutment with the hand-layered technique. After 3 years, clinical, esthetic, and radiographic parameters were assessed. Results: Group A exhibited one dropout patient and one failure resulting in a survival rate of 89% after 3 years and two failures for Group B (90%). Clinical parameters presented healthy peri-implant soft tissues. Overall, no crestal bone level changes were observed (mean DIB of 0.13 mm [Group A] and 0.24 mm [Group B]). There were no significant differences at baseline, 6 months, and 1 and 3 years for DIB values between the two groups. PES and WES values evaluated at all three time points indicated stability over time for both groups and pleasing esthetic outcomes. Conclusions: Both implant-supported prosthetic pathways represent a valuable treatment option for the restoration of implant crowns in the anterior maxilla.

Purpose: Autogenous bone grafts are considered a "gold standard. " The success of autografts mainly depends on their ability to promote an osteogenic response. The aim of this study was to collect autogenous bone during implant osteotomy preparation using two different drilling protocols and to evaluate and compare the proliferation and differentiation ability of the collected bone particles. Materials and Methods: Autogenous bone particles were harvested from 20 patients during implant osteotomy preparation using two different drilling protocols: (1) standard drilling protocol with saline irrigation (according to the manufacturer's recommendation) and (2) low-speed drilling protocol without saline irrigation (speed < 200 rpm). Collected bone samples were cultured in growth medium, and after 2 to 3 weeks, cells that grew out from bone grafts were cultured in the normal medium as well as in osteogenic medium for days 0, 4, 7, and 20. Scanning electron microscopy, alizarin red/toluidine blue staining, DNA, ALP, and calcium content measurements were performed. Repeated measures analysis of variance (ANOVA) with Bonferroni's test was employed to analyze the data of this study. Results: The total DNA content was significantly higher for the low-speed drilling samples compared with the standard drilling on day 4 (P

Objectives: To assess the adjunctive effect of systemic amoxicillin (AMX) and metronidazole (MTZ) in patients receiving non-surgical treatment (NST) for peri-implantitis (PI). Materials and methods: Thirty-seven patients were randomized into an experimental group treated with NST plus AMX + MTZ (N = 18) and a control group treated with NST alone (N = 19). Clinical parameters were evaluated at 12 weeks post-treatment. The primary outcome was the change in peri-implant pocket depth (PIPD) from baseline to 12 weeks, while secondary outcomes included bleeding on probing (BoP), suppuration on probing (SoP), and plaque. Data analysis was performed at patient level (one target site per patient). Results: All 37 patients completed the study. Both groups showed a significant PIPD reduction after NST. The antibiotics group showed a higher mean reduction in PIPD at 12 weeks, compared with the control group (2.28 ± 1.49 mm vs. 1.47 ± 1.95 mm), however, this difference did not reach statistical significance. There was no significant effect of various potential confounders on PIPD reduction. Neither treatment resulted in significant improvements in BoP at follow-up; 30 of 37 (81%) target sites still had BoP after treatment. Only two implants, one in each group, exhibited a successful outcome defined as PIPD

In order to evaluate loading methods and the dose dependency of bone morphogenetic protein 2 (BMP-2) in ectopic bone formation, an osteoinductive material consisting of commercially available coralline hydroxyapatite (CHA) was coated with a layer of biomimetic calcium phosphate (BioCaP) containing BMP-2 in different ways. Eight groups—each containing samples of 0.25 g CHA—were formed and coated with, respectively, BioCaP with internally incorporated BMP-2 in concentrations of 1, 5, 10, 20, 40 and 60 µg per sample, and the two control groups with BioCaP only and BioCaP with 20 µg of adsorbed BMP-2 per sample. The samples were implanted subcutaneously in 27 male Wistar rats. The histological results show that there is no bone formation in the group in which no BMP-2 was included. All samples with BioCaP containing BMP-2 show bone formation. The group with 20 µg of adsorbed BMP-2 per sample shows the least bone formation. Coating-incorporated BMP-2 is more efficient in inducing bone formation than adsorbed BMP-2. The group with 5 µg of coating-incorporated BMP-2 per sample shows the most bone formation. Increasing the amount of coating-incorporated BMP-2 up to 60 µg does not improve ectopic bone formation.

© 2021 The Authors. Journal of Clinical Periodontology published by John Wiley & Sons Ltd.Aim: To study the peri-implant submucosal microbiome in relation to implant disease status, dentition status, smoking habit, gender, implant location, implant system, time of functional loading, probing pocket depth (PPD), and presence of bleeding on probing. Materials and Methods: Biofilm samples were collected from the deepest peri-implant site of 41 patients with paper points, and analysed using 16S rRNA gene pyrosequencing. Results: We observed differences in microbial profiles by PPD, implant disease status, and dentition status. Microbiota in deep pockets included higher proportions of the genera Fusobacterium, Prevotella, and Anaeroglobus compared with shallow pockets that harboured more Rothia, Neisseria, Haemophilus, and Streptococcus. Peri-implantitis (PI) sites were dominated by Fusobacterium and Treponema compared with healthy implants and peri-implant mucositis, which were mostly colonized by Rothia and Streptococcus. Partially edentulous (PE) individuals presented more Fusobacterium, Prevotella, and Rothia, whereas fully edentulous individuals presented more Veillonella and Streptococcus. Conclusions: PPD, implant disease status, and dentition status may affect the submucosal ecology leading to variation in composition of the microbiome. Deep pockets, PI, and PE individuals were dominated by Gram-negative anaerobic taxa.

Objectives: The purpose of this randomized clinical trial was to compare the required time of potential clinical adjustments of posterior screw-retained monolithic zirconia implant retained crowns based on intraoral optical scanning (IOS) or conventional impressions. Materials and methods: Patients with posterior tissue level implants (Straumann RN) replacing solitary teeth were recruited. Of all patients, impressions were taken with both an IOS (3M™ TDS) and a conventional (polyether) pick-up impression. Randomization was performed after impression taking and patients were to receive either a crown based on the digital or the conventional impression. The time required for adjustments at placement was recorded. Additionally, restoration survival and mechanical complications with a follow-up of one year were documented. Results: Thirty two patients with 45 implants were included: 23 restorations in the test (IOS) and 22 in the control (conventional) group. The average adjustment time was 3.35 min (SD ± 3.38, range: 0–11 min) for the digital versus 6.09 min (SD ± 4.63, range: 0–18 min) for the conventional impressions (p =.039). A proper fit (no adjustments required) was achieved 39,1% in the digital and 18,2% conventional group respectively. All 45 restorations could be placed within the two planned appointments and only two minor mechanical complications occurred during the first year of function. Conclusions: The use of IOS resulted in shorter adjustment times at try-in than conventional impressions for solitary CAD/CAM implant restorations. Screw-retained solitary monolithic zirconia restorations on ti-base abutments show low complication- and survival rates in the short term.

Objectives: The aim of this investigation was to evaluate whether the use of a provisional implant‐supported crown improves the final esthetic outcome of implant crowns that are placed within esthetic sites.Materials and Methods: Twenty endosseous implants were inserted in sites 13 to 23 (FDI) in 20 patients. Following the reopening procedure, a randomization process assigned them to either cohort group 1: a provisional phase with soft tissue conditioning using the “dynamic compression technique” or cohort group 2: without a provisional phase. Screw‐retained all ceramic crowns were inserted. Clinical follow‐up appointments were completed at 36 months evaluating clinical, radiographic outcomes, and implant success and survival.Results: After 3 years, all implants survived; one implant‐supported crown was excluded from the study due to adjacent tooth failure replaced with a further implant supported crown. Modified pink esthetic score (ModPES) scores were significantly different between groups 1 and 2 (P = .018); white esthetic scores (WES) were not statistically different between both groups (P = .194). Mean values of combined modPES and WES were 15.6 for group 1, with a SD of 3.20. Group 2 had a mean combined modPES and WES of 12.2, with a SD of 3.86. Mean bone loss after 3 year was −0.05 and −0.04 mm for groups 1 and 2 respectively, without being statistically significant.Conclusion: Fixed implant‐supported provisionals improve the final esthetic outcome of the peri‐implant mucosa.

Infected bone defect healing is hindered by infection and compromised bone regenerative capacity. In this study, we designed a dual functional bone‐defect‐filling material with a sequential release system, that is, a burst release of a potent antibacterial agent, hydroxypropyltrimethyl ammonium chloride chitosan (HACC), followed by a controlled release of osteoinductive bone morphogenic protein (BMP2) to repair the infected bone defect. Minimum bactericidal concentration (MBC) of HACC against methicillin‐resistant Staphylococcus aureus was 40 μg/mL. HACC at 40 μg/mL did not affect preosteoblast proliferation and did not influence the BMP2‐induced alkaline phosphatase activity, osteocalcin expression, and matrix mineralization. in vitro release profile revealed burst release of HACC followed by a slow release of BMP2. in vivo bone formation was observed only in the BMP2‐containing groups. HACC did not influence of biomimetic calcium phosphate (BioCaP) resorption and BMP2‐induced bone formation. In conclusion, the optimized HACC/BMP2‐incorporated BioCaP complex showed strong antibacterial effect and robustly enhanced osteoinduction both in vitro and in vivo.

Background The aim of this systematic review was to provide an update on the contemporary knowledge and scientific development of augmented reality (AR) and virtual reality (VR) in dental medicine, and to identify future research needs to accomplish its clinical translation. Method A modified PICO-strategy was performed using an electronic (MEDLINE, EMBASE, CENTRAL) plus manual search up to 12/2018 exploring AR/VR in dentistry in the last 5 years. Inclusion criteria were limited to human studies focusing on the clinical application of AR/VR and associated field of interest in dental medicine. Results The systematic search identified 315 titles, whereas 87 abstracts and successively 32 full-texts were selected for review, resulting in 16 studies for final inclusion. AR/VR-technologies were predominantly used for educational motor skill training (n = 9 studies), clinical testing of maxillofacial surgical protocols (n = 5), investigation of human anatomy (n = 1), and the treatment of patients with dental phobia (n = 1). Due to the heterogeneity of the included studies, meta-analyses could not be performed. Conclusions The overall number of includable studies was low; and scientifically proven recommendations for clinical protocols could not be given at this time. However, AR/VR-applications are of increasing interest and importance in dental under- and postgraduate education offering interactive learning concepts with 24/7-access and objective evaluation. In maxillofacial surgery, AR/VR-technology is a promising tool for complex procedures and can help to deliver predictable and safe therapy outcomes. Future research should focus on establishing technological standards with high data quality and developing approved applications for dental AR/VR-devices for clinical routine.

Pathological stimuli, such as bacterial activity, dental bleaching, and nonpolymerized resin monomers, can cause death of dental pulp cells (DPCs) through oxidative stress- (OS-) induced mitochondrial dysfunction. However, the crucial molecular mechanisms that mediate such a phenomenon remain largely unknown. OS is characterized by the overproduction of reactive oxygen species (ROS), e.g., H2O2, O2−, and ⋅OH. Mitochondria are a major source of ROS and the principal attack target of ROS. Cyclophilin D (CypD), as the only crucial protein for mitochondrial permeability transition pore (mPTP) induction, facilitates the opening of mPTP and causes mitochondrial dysfunction, leading to cell death. In the present study, we hypothesized that CypD-mediated mitochondrial molecular pathways were closely involved in the process of OS-induced death of human DPCs (HDPCs). We tested the phenotypic and molecular changes of HDPCs in a well-established OS model—H2O2 treatment. We showed that H2O2 dramatically reduced the viability and increased the death of HDPCs in a time- and dose-dependent manner by performing MTT, flow cytometry, and TUNEL assays and quantifying the expression changes of Bax and Bcl-2 proteins. H2O2 also induced mitochondrial dysfunction, as reflected by the increased mitochondrial ROS, reduced ATP production, and activation of mPTP (decreased mitochondrial membrane potential and enhanced intracellular Ca2+ level). An antioxidant (N-acetyl-L-cysteine) effectively preserved mitochondrial function and significantly attenuated H2O2-induced cytotoxicity and death. Moreover, H2O2 treatment markedly upregulated the CypD protein level in HDPCs. Notably, genetic or pharmacological blockade of CypD significantly attenuated H2O2-induced mitochondrial dysfunction and cell death. These findings provided novel insights into the role of a CypD-dependent mitochondrial pathway in the H2O2-induced death in HDPCs, indicating that CypD may be a potential therapeutic target to prevent OS-mediated injury in dental pulp.

To compare the fit and clinical performance of screw-retained monolithic zirconia implant fixed dental prostheses (FDPs) based on either intraoral optical scanning (IOS) or conventional impressions.Patients with two posterior tissue-level implants (Straumann Regular Neck) replacing two or three adjacent teeth were recruited. Impressions were taken with both IOS (True Definition Scanner, 3M ESPE) and a conventional (polyether) pick-up impression. Double-blind randomization was performed after impression-taking, and patients were to receive an FDP based on either the digital or the conventional impression. The fit was evaluated, and the time required for adjustments was recorded. Additionally, survival and technical complication rates with a follow-up of 1 year were documented.A total of 38 patients requiring 45 FDPs were included: 24 FDPs in the test (IOS) and 21 in the control (conventional) group. The average adjustment time was 6.92 minutes (SD: ± 10.84, range: 0 to 49 minutes) for digital vs 12.38 minutes (SD: ± 14.52, range: 0 to 54 minutes) for conventional impressions (P = .090). A proper fit (no adjustments) was achieved in 33.3% of the digital and 28.6% of the conventional group. Forty-two FDPs could be placed within the two planned appointments, and 3 FDPs exhibited an unacceptable fit and required an extra appointment. Eight technical complications occurred during the first year of function. The overall restoration survival rate was 100%.The clinical fit of CAD/CAM FDPs based on digital impressions is comparable to conventional impressions. Screw-retained monolithic zirconia FDPs on Ti-base abutments show low major complication and survival rates in the short term.

Objectives: To present a workflow of virtual implant planning and guided implant surgery with magnetic resonance imaging (MRI) and virtual dental models without the use of ionizing radiation. Methods: Five patients scheduled for implant placement underwent an MR examination at three Tesla using individualized 2D and 3D turbo spin-echo (TSE) sequences and dedicated head coils. The MRI data and virtual dental models derived from either optical model scans or intraoral scans were imported to a virtual implant planning software (coDiagnostiX, Dental Wings, Montreal, Canada). Virtual prosthetic planning and implant planning were performed regarding the hard and soft tissue anatomy. A drill guide was designed on the virtual dental model using computer-aided design (CAD) and manufactured in-house, using a 3D printer (Eden 260V, Stratasys, Eden Prairie, MN, USA). Results: The MRI displayed all relevant anatomical structures for dental implant planning such as cortical and cancellous bone, floor of the nasal and maxillary sinus, inferior alveolar nerve and neighboring teeth. The manual alignment of virtual dental models with the MRI was possible using anatomical landmarks. Dental implant planning, CAD/CAM of a drill guide and fully guided implant placement were successfully performed. Conclusions: Guided implant surgery is feasible with MRI without ionizing radiation. Further studies will have to be conducted to study the accuracy of the presented protocol and compare it to the current workflow of guided surgery using CBCT.

Objective To report and discuss the lessons learned from the conduct of a clinical study on the associations between sleep bruxism and (peri-)implant complications, the protocol of which has been pre-published. Materials and methods A single-center, double-blind, prospective cohort study with a 2 year follow-up was performed in the Academic Centre for Dentistry Amsterdam (ACTA), The Netherlands. Eleven adult participants were included, where an inclusion of 98 was planned. Sleep bruxism was assessed by multiple single-channel electromyographic (EMG) recordings. Main outcomes were biological and technical complications. Results of the study are presented alongside with comments on encountered difficulties. Results Insufficient participant recruitment and failed EMG recordings were encountered. The small sample size did not allow answering the study’s main aim, and was mainly attributed to the study’s protocol complexity. EMG recording failures were attributed to insufficient quality of the EMG signal and detachments of the electrode. Discussion The lessons learned from the conduct of this study can be used to design successful future clinical studies. Conclusions Adequate participant recruitment, effective EMG recordings, and a careful selection of predictor variables are important ingredients for the successful conduct of a longitudinal clinical study on the association between sleep bruxism and (peri-)implant complications.

OBJECTIVES: The aim of Working Group 3 was to focus on three topics that were assessed using patient-reported outcome measures (PROMs). These topics included the following: (a) the aesthetics of tooth and implant-supported fixed dental prostheses focusing on partially edentulous patients, (b) a comparison of fixed and removable implant-retained prostheses for edentulous populations, and (c) immediate versus early/conventional loading of immediately placed implants in partially edentate patients. PROMs include ratings of satisfaction and oral health-related quality of life (QHRQoL), as well as other indicators, that is, pain, general health-related quality of life (e.g., SF-36). MATERIALS AND METHODS: The Consensus Conference Group 3 participants discussed the findings of the three systematic review manuscripts. Following comprehensive discussions, participants developed consensus statements and recommendations that were then discussed in larger plenary sessions. Following this, any necessary modifications were made and approved. RESULTS: Patients were very satisfied with the aesthetics of implant-supported fixed dental prostheses and the surrounding mucosa. Implant neck design, restorative material, or use of a provisional restoration did not influence patients' ratings. Edentulous patients highly rate both removable and fixed implant-supported prostheses. However, they rate their ability to maintain their oral hygiene significantly higher with the removable prosthesis. Both immediate provisionalization and conventional loading receive positive patient-reported outcomes. CONCLUSIONS: Patient-reported outcome measures should be gathered in every clinical study in which the outcomes of oral rehabilitation with dental implants are investigated. PROMs, such as patients' satisfaction and QHRQoL, should supplement other clinical parameters in our clinical definition of success. ispartof: CLINICAL ORAL IMPLANTS RESEARCH vol:29 pages:270-275 ispartof: location:Denmark status: published

Aim: This systematic review and meta-analysis were conducted to assess and compare the accuracy of conventional and digital implant impressions. The review was registered on the PROSPERO register (registration number: CRD42016050730). Material and Methods: A systematic literature search was conducted adhering to PRISMA guidelines to identify studies on implant impressions published between 2012 and 2017. Experimental and clinical studies at all levels of evidence published in peer-reviewed journals were included, excluding expert opinions. Data extraction was performed along defined parameters for studied specimens, digital and conventional impression specifications and outcome assessment. Results: Seventy-nine studies were included for the systematic review, thereof 77 experimental studies, one RCT and one retrospective study. The study setting was in vitro for most of the included studies (75 studies) and in vivo for four studies. Accuracy of conventional impressions was examined in 59 studies, whereas digital impressions were examined in 11 studies. Nine studies compared the accuracy of conventional and digital implant impressions. Reported measurements for the accuracy include the following: (a) linear and angular deviations between reference models and test models fabricated with each impression technique; (b) three-dimensional deviations between impression posts and scan bodies respectively; and (c) fit of implant-supported frameworks, assessed by measuring marginal discrepancy along implant abutments.) Meta-analysis was performed of 62 studies. The results of conventional and digital implant impressions exhibited high values for heterogeneity. Conclusions: The available data for accuracy of digital and conventional implant impressions have a low evidence level and do not include sufficient data on in vivo application to derive clinical recommendations.

Objectives: To assess the literature on the accuracy of static computer-assisted implant surgery in implant dentistry. Materials and Methods: Electronic and manual literature searches were conducted to collect information about the accuracy of static computer-assisted implant systems. Meta-regression analysis was performed to summarise the accuracy studies. Results: From a total of 372 articles. 20 studies, one randomised controlled trial (RCT), eight uncontrolled retrospective studies and 11 uncontrolled prospective studies were selected for inclusion for qualitative synthesis. A total of 2,238 implants in 471 patients that had been placed using static guides were available for review. The meta-analysis of the accuracy (20 clinical) revealed a total mean error of 1.2 mm (1.04 mm to 1.44 mm) at the entry point, 1.4 mm (1.28 mm to 1.58 mm) at the apical point and deviation of 3.5°(3.0° to 3.96°). There was a significant difference in accuracy in favour of partial edentulous comparing to full edentulous cases. Conclusion: Different levels of quantity and quality of evidence were available for static computer-aided implant surgery (s-CAIS). Based on the present systematic review and its limitations, it can be concluded that the accuracy of static computer-aided implant surgery is within the clinically acceptable range in the majority of clinical situations. However, a safety marge of at least 2 mm should be respected. A lack of homogeneity was found in techniques adopted between the different authors and the general study designs.

Purpose: To evaluate the feasibility of a commercially available immediate root analog implant system Replicate (Natural Dental Implants). Materials and Methods: Five consecutive patients in need of an implant in the premolar region were recruited for this pilot study. Following clinical examination, a cone beam computed tomography scan was made and the dental impressions digitized. On the basis of the superimposition of these datasets, a three-dimensional (3D) envelope was created for the selected tooth. Subsequently, the tooth root at the prospective implant site was segmented to create a 3D surface, and the obtained mesh data were used as the basis for designing a single-piece root analog implant within the 3D envelope. The designed root analog implant was fabricated using a five-axis computer-aided manufacturing machine. The root analog implants were inserted following flapless minimally invasive root extraction. Following 3 months of uninterrupted healing, definitive restorations were fabricated. Peri-implant clinical and radiographic measurements were obtained up to 12 months follow-up. Results: All patients functioned well following 12 months of functional loading. Within one patient, one of the two root analog implants failed early. Peri-implant clinical and radiographic measurements demonstrated a stable situation after 12 months of functional loading. Conclusion: A novel digital approach for immediately restoring single teeth using root analog implants was introduced. In the future, long-term evaluation of the root analog implant technique is necessary to evaluate the success and survival of implants that were inserted using this technique.

The aim of this study is to test the cleaning effect and surface modification of a new implant surface treatment on explanted dental implants and titanium discs. It is a modified air powder abrasive (APA) treatment applied using osteoconductive powders. Twenty‐eight in vitro Ca‐precipitated organic film‐coated titanium discs and 13 explanted dental implants were treated. In a 2‐step approach, 3 powders were used: hydroxylapatite (HA) and biomimetic calcium phosphate (BioCaP), which are osteoconductive, and erythritol, which is not. APA treatment was applied. (Air pressure: 2.4 bar; water flow for cleaning: 41.5 ml/min, for Coating 1: 2.1 ml/min, and for Coating 2: 15.2 ml/min.) The test groups were as follows: Group 1: HA cleaning + BioCaP Coating 1; Group 2: HA cleaning + BioCaP Coating 2; Group 3: erythritol cleaning + BioCaP Coating 1; Group 4: erythritol cleaning + BioCaP Coating 2; Group 5: HA cleaning; Group 6: erythritol cleaning; and control: no powder. Cleaned areas were calculated by point counting method. Surface changes and chemical content were evaluated using light microscopy, scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy. Cleaning effect between groups was compared by a pairwise Student's t test. The significance level was fixed at p

Purpose: To evaluate the influence of fabrication method and finish line design on marginal and internal fit of full-coverage interim restorations. Methods: Four typodont models of maxillary central-incisor were prepared for full-coverage restorations. Four groups were defined; knife-edge (KE), chamfer (C), rounded-shoulder (RS), rounded-shoulder with bevel (RSB). All preparations were digitally scanned. A total of 80 restorations were fabricated; 20 per group (SLA/3D-printed n = 10, milled n = 10). All restorations were positioned on the master die and scanned using micro-computed tomography. The mean gaps were measured digitally (ImageJ). The results were compared using MANOVA (α =.05). Results: Internal and marginal gaps were significantly influenced by fabrication method (P =.000) and finish-line design (P =.000). 3D-Printed restorations showed statistically significant lower mean gap compared to milled restorations at all points (P =.000). The mean internal gap for 3D-printed restorations were 66, 149, 130, 95 μm and for milled restorations were 89, 177, 185, 154 μm for KE, C, RS, RSB respectively. The mean absolute marginal discrepancy in 3D-printed restorations were (30, 41, 30, 28 μm) and in milled restorations were (56, 54, 52, 38 μm) for KE, C, RS, RSB respectively. Conclusions: The fabrication methods showed more of an influence on the fit compared to the effect of the finish-line design in both milled and printed restorations. SLA-printed interim restorations exhibit lower marginal and internal gap than milled restorations. Nonetheless, for both techniques, all values were within the reported values for CAD/CAM restorations. Significance: 3D-printing can offer an alternative fabrication method comparable to those of milled restorations.

Objectives: To investigate which opinions among dentists are associated with level of technology use, when characteristics of the dentist and dental practice, as well as motivating work aspects are taken into account. Methods: A total of 1000 general dental practitioners in the Netherlands received a questionnaire on digital technologies they use, opinions on using technologies and related motivating work aspects. Questions were derived from expert interviews, the Dentists’ Experienced Job Resources Scale and literature on technology implementation. Technology use was measured as the number of technologies used, and divided into three technology user groups: low (using 0-4 technologies, mostly administrative and radiographic technologies), intermediate (using 5-7, more varied technologies) and high technology users (using 8-12, including more innovative diagnostic technologies). Opinions on technology use and motivating work aspects were analysed using principal components analysis (PCA) and exploratory factor analysis. Scores on all components and factors were calculated for each respondent by computing the mean of all valid responses on the underlying items. Differences in these scale scores on opinions among the technology user groups were assessed using one-way analysis of variance and Kruskal–Wallis tests. A multiple linear regression analysis assessed the association of scale scores about opinions on technology use with the sum of technologies used, taking into account motivating work aspects and characteristics of the dentist and dental practice. Results: The response rate was 31%. Dentists who were high technology users perceived technologies as yielding more improvements in quality of care, adding more value to the dental practice and being easier to use, than low technology users. High technology users thought technologies added more value to their work and they reported higher skills and resources. They also focused more on technologies and thought these are more ready to use than low technology users. High technology users derived more motivation from “Immediate results” and “Craftsmanship” than low technology users. Personal and practice characteristics, motivating work aspects, and the opinion scales “Focus” and “Added value to dentist” explained 50% of the variance in the number of technologies a dentist uses. Conclusion: Opinions on digital technologies among dentists and motivating work aspects vary with level of technology use. Being more focused on technologies and perceiving a higher added value from using them are associated with using more digital dental technologies, when taking into account motivating work aspects and characteristics of the dentist and dental practice.

This systematic review provides an overview of studies on autotransplantation techniques using rapid prototyping for preoperative fabrication of donor tooth replicas for preparation of the neo-alveolus. Different three-dimensional autotransplantation techniques and their treatment outcomes are discussed. The systematic literature search yielded 19 articles that satisfied the criteria for inclusion. These papers described one case–control study, four clinical observational studies, one study with a clinical and in vitro part, four in vitro studies, and nine case reports. The in vitro studies reported high accuracy for the printing and planning processes. The case reports all reported successful transplantation without any pathological signs. The clinical studies reported a short extraoral time of the donor tooth, with subsequent success and survival rates of 80.0–91.1% and 95.5–100%, respectively. The case–control study reported a significant decrease in extraoral time and high success rates with the use of donor tooth replicas. In conclusion, the use of a preoperatively designed surgical guide for autotransplantation enables accurate positional planning, increases the ease of surgery, and decreases the extraoral time. However, the quality of the existing body of evidence is low. Further research is therefore required to investigate the clinical advantages of this innovative autotransplantation technique.

Purpose The aim of this study was to evaluate the dimensional accuracy, surface topography of a custom designed, 3D-printed zirconia dental implant and the mechanical properties of printed zirconia discs. Materials and methods A custom designed implant was 3D-printed in zirconia using digital light processing technique (DLP). The dimensional accuracy was assessed using the digital-subtraction technique. The mechanical properties were evaluated using biaxial flexure strength test. Three different build angles were adopted to print the specimens for the mechanical test; 0°( V ertical), 45° ( O blique) and 90°(Horizontal) angles. The surface topography, crystallographic phase structure and surface roughness were evaluated using scanning electron microscopy analysis (SEM), X-ray diffractometer and confocal microscopy respectively. Results The printed implant was dimensionally accurate with a root mean square (RMSE) value of 0.1 mm. The Weibull analysis revealed a statistically significant higher characteristic strength (1006.6 MPa) of 0° printed specimens compared to the other two groups and no significant difference between 45° (892.2 MPa) and 90° (866.7 MPa) build angles. SEM analysis revealed cracks, micro-porosities and interconnected pores ranging in size from 196 nm to 3.3 µm. The mean Ra (arithmetic mean roughness) value of 1.59 µm (±0.41) and Rq (root mean squared roughness) value of 1.94 µm (±0.47) was found. A crystallographic phase of primarily tetragonal zirconia typical of sintered Yttria tetragonal stabilized zirconia (Y-TZP) was detected. Conclusions DLP prove to be efficient for printing customized zirconia dental implants with sufficient dimensional accuracy. The mechanical properties showed flexure strength close to those of conventionally produced ceramics. Optimization of the 3D-printing process parameters is still needed to improve the microstructure of the printed objects.