Artifact Properties of Dental Ceramic and Titanium Implants in MRI

Aim Assessment of the visualization of titanium and ceramic dental implants using various isotropic three-dimensional magnetic resonance imaging (MRI) methods. Materials and Methods 21 dental implants (7 ceramic, 14 titanium) were scanned in vitro with a spatially isotropically resolved three-dimensional gradient echo (FFE), a turbo spin echo (SE) and an ultra-short-echo time (UTE) imaging technique. The resulting absolute volumes of the implants were quantified and the relative error to the theoretical volume was calculated. Results Ceramic implants and their periphery could be displayed well in all cases. The observed mean relative error results were 5.4 ± 2.3 % (UTE) to 6.5 ± 4.3 % (FFE). No significant difference was observed between the investigated MRI methods. The transition between implant and surrounding agarose could be shown in all cases without artifacts. Titanium implants resulted in mean relative errors between 1314 ± 350 % (FFE) and 2157 ± 810 % (SE). Here, significant differences were observed between the FFE and the SE and between the UTE and the SE sequence. The periphery of the implants could not be displayed in any case. Conclusion Use of the MRI technique for the diagnosis of peri-implantitis, the assessment of anatomical structures and planning of dental implantation is currently very limited but could be used more frequently, provided there are no disturbing or imaging-disturbing materials in the region of interest. MRI technology is not suitable in case of titanium implants. When using ceramic implants, MRI technology is an option. Key points Citation Format

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Effect of Titanium Implants Coated with Radiation-Crosslinked Collagen on Stability and Osseointegration in Rat Tibia

Materials ◽

10.3390/ma11122520 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2520 ◽

Cited By ~ 4

Author(s):

Eun-Bin Bae ◽

Ji-Hyun Yoo ◽

Sung-In Jeong ◽

Min-Su Kim ◽

Youn-Mook Lim ◽

...

Keyword(s):

Gamma Radiation ◽

Human Mesenchymal Stem Cells ◽

Region Of Interest ◽

Bone Volume ◽

Titanium Implants ◽

Control Group ◽

Gene Expressions ◽

Significant Difference

This study aimed to evaluate the titanium (Ti) implants coated with collagen type Ⅰ crosslinked using gamma-irrigation or glutaraldehyde (GA). The in vitro surface observations, quantification assay, and cell studies using human mesenchymal stem cells (hMSCs) were conducted. For in vivo experiments, the implants were divided into three groups and inserted into the rat tibias: control group (non-treated Ti implant), GA group (Ti implants coated with GA-crosslinked collagen) and 25 kGy group (Ti implants coated with gamma-radiation-crosslinked collagen at dose of 25 kGy). The animals were sacrificed at 4 weeks after implantation and the tissue sections were obtained. New bone volume (mm3) and bone-to-implant contact (BIC, %) within the region of interest (ROI) was measured. The in vitro results showed the highest osteogenic differentiation and levels of osteogenesis-related gene expressions in the 25 kGy group without cytotoxicity. The new bone volume of GA group was significantly higher than the control (p < 0.05). In the result of the BIC, the 25 kGy group was significantly higher than the control (p < 0.05). However, there was no significant difference between the experimental groups. Within the limitations of this study, Ti implant coated with gamma-radiation-crosslinked collagen has potential utility without side effects from chemical agents.

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Direct Metal Laser Sintering Titanium Dental Implants: A Review of the Current Literature

International Journal of Biomaterials ◽

10.1155/2014/461534 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 47

Author(s):

F. Mangano ◽

L. Chambrone ◽

R. van Noort ◽

C. Miller ◽

P. Hatton ◽

...

Keyword(s):

Dental Implants ◽

Methodological Quality ◽

Meta Analysis ◽

Three Dimensional ◽

Laser Sintering ◽

Titanium Implants ◽

Human Studies ◽

Direct Metal Laser Sintering ◽

Titanium Dental Implants

Statement of Problem. Direct metal laser sintering (DMLS) is a technology that allows fabrication of complex-shaped objects from powder-based materials, according to a three-dimensional (3D) computer model. With DMLS, it is possible to fabricate titanium dental implants with an inherently porous surface, a key property required of implantation devices.Objective. The aim of this review was to evaluate the evidence for the reliability of DMLS titanium dental implants and their clinical and histologic/histomorphometric outcomes, as well as their mechanical properties.Materials and Methods. Electronic database searches were performed. Inclusion criteria were clinical and radiographic studies, histologic/histomorphometric studies in humans and animals, mechanical evaluations, andin vitrocell culture studies on DMLS titanium implants. Meta-analysis could be performed only for randomized controlled trials (RCTs); to evaluate the methodological quality of observational human studies, the Newcastle-Ottawa scale (NOS) was used.Results. Twenty-seven studies were included in this review. No RCTs were found, and meta-analysis could not be performed. The outcomes of observational human studies were assessed using the NOS: these studies showed medium methodological quality.Conclusions. Several studies have demonstrated the potential for the use of DMLS titanium implants. However, further studies that demonstrate the benefits of DMLS implants over conventional implants are needed.

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Comparison of 3D-Printed Dental Implants with Threaded Implants for Osseointegration: An Experimental Pilot Study

Materials ◽

10.3390/ma13214815 ◽

2020 ◽

Vol 13 (21) ◽

pp. 4815

Author(s):

Ling Li ◽

Jungwon Lee ◽

Heithem Ben Amara ◽

Jun-Beom Lee ◽

Ki-Sun Lee ◽

...

Keyword(s):

Dental Implants ◽

Three Dimensional ◽

Primary Stability ◽

Titanium Implants ◽

Implant Stability ◽

Implant Surgery ◽

Post Surgery ◽

Significant Difference ◽

3D Printed ◽

Stability Measurements

This study aimed to compare bone healing and implant stability for three types of dental implants: a threaded implant, a three-dimensional (3D)-printed implant without spikes, and a 3D-printed implant with spikes. In four beagle dogs, left and right mandibular premolars (2nd, 3rd, and 4th) and 1st molars were removed. Twelve weeks later, three types of titanium implants (threaded implant, 3D-printed implant without spikes, and 3D-printed implant with spikes) were randomly inserted into the edentulous ridges of each dog. Implant stability measurements and radiographic recordings were taken every two weeks following implant placement. Twelve weeks after implant surgery, the dogs were sacrificed and bone-to-implant contact (BIC) and bone area fraction occupied (BAFO) were compared between groups. At implant surgery, the primary stability was lower for the 3D-printed implant with spikes (74.05 ± 5.61) than for the threaded implant (83.71 ± 2.90) (p = 0.005). Afterwards, no significant difference in implants’ stability was observed between groups up to post-surgery week 12. Histomorphometrical analysis did not reveal a significant difference between the three implants for BIC (p = 0.101) or BAFO (p = 0.288). Within the limits of this study, 3D-printed implants without spikes and threaded implants showed comparable implant stability measurements, BIC, and BAFO.

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Macrophagic Inflammatory Response Next to Dental Implants with Different Macro- and Micro-Structure: An In Vitro Study

Applied Sciences ◽

10.3390/app11125324 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5324

Author(s):

Maria Menini ◽

Francesca Delucchi ◽

Domenico Baldi ◽

Francesco Pera ◽

Francesco Bagnasco ◽

...

Keyword(s):

Inflammatory Response ◽

Dental Implants ◽

In Vitro Study ◽

Titanium Implants ◽

Implant Surface ◽

Bone Implant ◽

Optimal Outcomes ◽

Negative Controls ◽

Inflammatory Effect

(1) Background: Intrinsic characteristics of the implant surface and the possible presence of endotoxins may affect the bone–implant interface and cause an inflammatory response. This study aims to evaluate the possible inflammatory response induced in vitro in macrophages in contact with five different commercially available dental implants. (2) Methods: one zirconia implant NobelPearl® (Nobel Biocare) and four titanium implants, Syra® (Sweden & Martina), Prama® (Sweden & Martina), 3iT3® (Biomet 3i) and Shard® (Mech & Human), were evaluated. After 4 h of contact of murine macrophage cells J774a.1 with the implants, the total RNA was extracted, transcribed to cDNA and the gene expression of the macrophages was evaluated by quantitative PCR (qPCR) in relation to the following genes: GAPDH, YWHAZ, IL1β, IL6, TNFα, NOS2, MMP-9, MMP-8 and TIMP3. The results were statistically analyzed and compared with negative controls. (3) Results: No implant triggered a significant inflammatory response in macrophages, although 3iT3 exhibited a slight pro-inflammatory effect compared to other samples. (4) Conclusions: All the samples showed optimal outcomes without any inflammatory stimulus on the examined macrophagic cells.

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Influence of the Thermal Treatment to Address a Better Osseointegration of Ti6Al4V Dental Implants: Histological and Histomorphometrical Study in a Rabbit Model

BioMed Research International ◽

10.1155/2018/2349698 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 12

Author(s):

Antonio Scarano ◽

Ezio Crocetta ◽

Alessandro Quaranta ◽

Felice Lorusso

Keyword(s):

Thermal Treatment ◽

Dental Implants ◽

Bone Healing ◽

Rabbit Model ◽

Titanium Implants ◽

Control Group ◽

Left Femur ◽

Bone Response ◽

First Choice ◽

Significant Difference

Background. Pure titanium continues to be the first choice for dental implants and represents the gold standard for their biocompatibility and physical and mechanical characteristics, while the titanium alloy (Ti6Al4V) has good mechanical properties. The surface structure of the titanium oxide layer formation on the surface influences and improves the bone response around dental implants. Purpose. The purpose of this study is to evaluate the influence of a thermal treatment of Ti6Al4V implant surfaces and the bone healing response in a rabbit model. Methods. Altogether sixteen implants with same design were inserted into the distal femoral metaphysis. A screw (13 mm long, 4 mm in diameter) was inserted in an implant bed. Each rabbit received two implants, one in the left femur and one in the right femur. The samples were histologically and histomorphometrically evaluated at 8 weeks. Results. A statistically significant difference (p = 0.000034) was present histologically in the percentages of bone-implant contact (BIC) between the test group (BIC = 69.25±4.49%.) and control group (BIC = 56.25 ± 4.8%) by one-way analysis of variance (ANOVA). Significance was set at p ≤ 0.05. Conclusions. The outcome of the present study indicates a novel approach to improving bone healing around titanium implants.

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Size-controlled human adipose-derived stem cell spheroids hybridized with single-segmented nanofibers and their effect on viability and stem cell differentiation

Biomaterials Research ◽

10.1186/s40824-021-00215-9 ◽

2021 ◽

Vol 25 (1) ◽

Author(s):

Jinkyu Lee ◽

Sangmin Lee ◽

Sung Min Kim ◽

Heungsoo Shin

Keyword(s):

Stem Cell ◽

Cell Function ◽

Average Length ◽

Three Dimensional ◽

Stem Cell Differentiation ◽

Cell Spheroids ◽

Significant Difference ◽

Vitro Analysis ◽

Physical And Chemical

Abstract Background Fabrication of three-dimensional stem cell spheroids have been studied to improve stem cell function, but the hypoxic core and limited penetration of nutrients and signaling cues to the interior of the spheroid were challenges. The incorporation of polymers such as silica and gelatin in spheroids resulted in relatively relaxed assembly of composite spheroids, and enhancing transport of nutrient and biological gas. However, because of the low surface area between cells and since the polymers were heterogeneously distributed throughout the spheroid, these polymers cannot increase the cell to extracellular matrix interactions needed to support differentiation. Methods We developed the stem cell spheroids that incorporate poly(ι-lactic acid) single-segmented fibers synthesized by electrospinning and physical and chemical fragmentation. The proper mixing ratio was 2000 cells/μg fibers (average length of the fibers was 50 μm - 100 μm). The SFs were coated with polydopamine to increase cell binding affinity and to synthesize various-sized spheroids. The function of spheroids was investigated by in vitro analysis depending on their sizes. For statistical analysis, Graphpad Prism 5 software (San Diego, CA, USA) was used to perform one-way analysis of variance ANOVA with Tukey’s honest significant difference test and a Student’s t-test (for two variables) (P < 0.05). Results Spheroids of different sizes were created by modulating the amount of cells and fibers (0.063 mm2–0.322 mm2). The fibers in the spheroid were homogenously distributed and increased cell viability, while cell-only spheroids showed a loss of DNA contents, internal degradation, and many apoptotic signals. Furthermore, we investigated stemness and various functions of various-sized fiber-incorporated spheroids. In conclusion, the spheroid with the largest size showed the greatest release of angiogenic factors (released VEGF: 0.111 ± 0.004 pg/ng DNA), while the smallest size showed greater effects of osteogenic differentiation (mineralized calcium: 18.099 ± 0.271 ng/ng DNA). Conclusion The spheroids incorporating polydopamine coated single-segmented fibers showed enhanced viability regardless of sizes and increased their functionality by regulating the size of spheroids which may be used for various tissue reconstruction and therapeutic applications.

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The biological seal of the implant–soft tissue interface evaluated in a tissue-engineered oral mucosal model

Journal of The Royal Society Interface ◽

10.1098/rsif.2012.0507 ◽

2012 ◽

Vol 9 (77) ◽

pp. 3528-3538 ◽

Cited By ~ 22

Author(s):

Wen L. Chai ◽

Ian M. Brook ◽

Anders Palmquist ◽

Richard van Noort ◽

Keyvan Moharamzadeh

Keyword(s):

Soft Tissue ◽

Cell Attachment ◽

Tritiated Water ◽

Three Dimensional ◽

Permeability Test ◽

Significant Difference ◽

Surface Topographies ◽

Tissue Interface

For dental implants, it is vital that an initial soft tissue seal is achieved as this helps to stabilize and preserve the peri-implant tissues during the restorative stages following placement. The study of the implant–soft tissue interface is usually undertaken in animal models. We have developed an in vitro three-dimensional tissue-engineered oral mucosal model (3D OMM), which lends itself to the study of the implant–soft tissue interface as it has been shown that cells from the three-dimensional OMM attach onto titanium (Ti) surfaces forming a biological seal (BS). This study compares the quality of the BS achieved using the three-dimensional OMM for four types of Ti surfaces: polished, machined, sandblasted and anodized (TiUnite). The BS was evaluated quantitatively by permeability and cell attachment tests. Tritiated water (HTO) was used as the tracing agent for the permeability test. At the end of the permeability test, the Ti discs were removed from the three-dimensional OMM and an Alamar Blue assay was used for the measurement of residual cells attached to the Ti discs. The penetration of the HTO through the BS for the four types of Ti surfaces was not significantly different, and there was no significant difference in the viability of residual cells that attached to the Ti surfaces. The BS of the tissue-engineered oral mucosa around the four types of Ti surface topographies was not significantly different.

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Feasibility of 3-Dimensional Visual Guides for Preparing Pediatric Zirconia Crowns: An In Vitro Study

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17165732 ◽

2020 ◽

Vol 17 (16) ◽

pp. 5732

Author(s):

Ho Yeon Kang ◽

Hyeonjong Lee ◽

Yong Kwon Chae ◽

Seoung-Jin Hong ◽

Yun Yeong Jeong ◽

...

Keyword(s):

Three Dimensional ◽

In Vitro Study ◽

Mixed Dentition ◽

Preparation Time ◽

Second Molar ◽

Significant Difference ◽

Distal Surface ◽

Zirconia Crowns ◽

Tooth Preparation

This study evaluated the feasibility of a tooth preparation guide for prefabricated zirconia crowns (PZCs). Three-dimensional surface data for PZCs of the left maxillary primary first molar and left mandibular primary second molar were obtained using a model scanner. The tooth preparation data were digitally designed to harmonize with the adjacent teeth on the mixed dentition model and visualized using a color-coded map, which presents the required amount of tooth reduction. Twenty participants were recruited for preparing teeth with and without using the tooth preparation guide. The following three parameters were evaluated: tooth preparation time, harmony score, and amount of tooth reduction. The preparation time when using the guide was significantly reduced (p < 0.05), and a significant difference was observed in the harmony scores for the maxillary primary first molar preparation. Furthermore, the amount of tooth reduction was significantly different for both maxillary and mandibular primary molars (p < 0.05) in terms of the occlusal distal surface and buccal line angle in the maxillary primary first molars, and the smooth surfaces, proximal surfaces, and mesial line angles in the mandibular primary second molars. Thus, the results suggest that a tooth preparation guide could facilitate better tooth preparation for PZCs.

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Dental Implants Surface in vitro Decontamination Protocols

European Journal of Dentistry ◽

10.1055/s-0040-1721550 ◽

2020 ◽

Author(s):

Vanessa Coelho Batalha ◽

Raquel Abreu Bueno ◽

Edemar Fronchetti Junior ◽

José Ricardo Mariano ◽

Gabriela Cristina Santin ◽

...

Keyword(s):

Photodynamic Therapy ◽

Sodium Bicarbonate ◽

Dental Implants ◽

Negative Control ◽

Titanium Implants ◽

Antimicrobial Photodynamic Therapy ◽

Significance Level ◽

Sterile Saline ◽

Number Of Patients

Abstract Objective The number of patients rehabilitated with dental implants has contributed to increased incidence of peri-implant diseases. Due to complex and difficult treatment, peri-implantitis is a challenge and an efficient clinical protocol is not yet established. Aim of this study was to evaluate the efficacy of two protocols for in vitro decontamination of dental implants surface. Material and Methods Twenty titanium implants (BioHE-Bioconect) were used. Implants were divided into five groups (n = 4). NC group (negative control): sterile implants; PC group (positive control): biofilm contaminated implants; S group: biofilm contaminated implants, brushed with sterile saline; SB group: biofilm contaminated implants, brushed with sterile saline and treated with air-powder abrasive system with sodium bicarbonate (1 minute); and antimicrobial photodynamic therapy (aPDT) group: biofilm contaminated implants, brushed with sterile saline and treated with antimicrobial photodynamic therapy (red laser + toluidine blue O). The implants were contaminated in vitro with subgingival biofilm and distributed in groups PC, S, SB, and aPDT. Each group received the respective decontamination treatment, except groups NC and PC. Then, all implants were placed in tubes containing culture medium for later sowing and counting of colony-forming units (CFUs). Statistical Analysis One-way analysis of variance and Tukey tests were performed, at 5% significance level. Results Significantly fewer CFUs were observed in the aPDT group (19.38 × 105) when compared with groups SB (26.88 × 105), S (47.75 × 105), and PC (59.88 × 105) (p < 0.01). Both the aPDT and SB groups were statistically different from the NC group (p < 0.01). Conclusion Proposed protocols, using air-powder abrasive system with sodium bicarbonate and aPDT, showed to be efficacious in the decontamination of dental implants surface in vitro.

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