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Elsayed A, Chaar MS, Kern M, Libecki W, Yazigi C. Wear resistance of CAD/CAM one-piece screw-retained hybrid-abutment-crowns made from different restorative materials. Clin Implant Dent Relat Res 2024; 26:281-288. [PMID: 37408517 DOI: 10.1111/cid.13245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/09/2023] [Accepted: 06/22/2023] [Indexed: 07/07/2023]
Abstract
INTRODUCTION The aim of this study was to measure the wear progress of three high performance polymers (HPP) materials as well as that of zirconia after artificial aging (simulated 2.5- and 5-year of clinical service with thermo-mechanical loading) and compare it with the well-documented wear of lithium disilicate. METHODS Forty implants were used to restore a maxillary first premolar, where the abutment and the crown were manufactured as hybrid-abutment-crown and connected to the implant using a titanium insert. The implants were randomly divided, according to the restorative materials used, into five groups: 3Y-TZP zirconia (Z), lithium disilicate (L), ceramic-reinforced polyetheretherketon (P), nano-hybrid composite resin (C) and polymer-infiltrated ceramic-network (E). All hybrid-abutment-crowns were produced using CAD/CAM technology. A design of a maxillary first premolar was created with an angle of 120° between the buccal and palatal cusps, which were designed as planes. The restorations were adhesively luted onto the titanium inserts, according to the manufacturers' recommendations for each material individually, by means of dual-curing luting resin with the exception of group P, where the blocks were pre-fitted (heat-pressed) with an integrated titanium insert. The suprastructures were assembled onto the implants through titanium screws. The screw channels were sealed with Teflon tape and composite resin filling material that was polished to high-gloss. All specimens underwent 1 200 000 thermo-dynamic loading cycles with 49 N in a dual-axis chewing simulator. Elastomeric impressions were made for all specimens after 600 000 and after 1 200 000 cycles. The corresponding impressions were imaged using a laser scanning microscope and then 3D-analyzed using the software (Geomagic Wrap) to measure the volume loss of the wear area for all specimens. Statistical analysis was performed using Wilcoxon-Test regarding the two different time measurements for each material. For the analysis of the material variable, Kruskal-Wallis test was conducted followed by Mann-Whitney test. RESULTS Group Z showed statistically the lowest volume loss compared to the other test materials, both after 600 000 and 1 200 000 cycles of artificial aging, with a median value of 0.002 mm3 volume loss after 1 200 000 cycles. In contrast, group E showed the highest volume loss with median values of 0.18 and 0.3 mm3 after 600 000 and 1 200 000 cycles, respectively. Artificial aging had significantly negative effect on the volume loss for all test materials. In addition, the choice of material had statistical influence on the outcome. CONCLUSION Monolithic zirconia ceramic demonstrated lower wear than that reported for enamel after simulated 5-year of clinical service, whereas all other test materials showed higher volume loss after artificial aging.
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Affiliation(s)
- Adham Elsayed
- Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University at Kiel, Kiel, Germany
| | - Mohamed Sad Chaar
- Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University at Kiel, Kiel, Germany
| | - Matthias Kern
- Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University at Kiel, Kiel, Germany
| | - Wojtek Libecki
- Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University at Kiel, Kiel, Germany
| | - Christine Yazigi
- Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University at Kiel, Kiel, Germany
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Poovarodom P, Rungsiyakull C, Suriyawanakul J, Li Q, Sasaki K, Yoda N, Rungsiyakull P. Effect of customized abutment taper configuration on bone remodeling and peri-implant tissue around implant-supported single crown: A 3D nonlinear finite element study. J Prosthodont 2023. [PMID: 37767904 DOI: 10.1111/jopr.13776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 08/24/2023] [Accepted: 09/23/2023] [Indexed: 09/29/2023] Open
Abstract
PURPOSE The optimal configuration of a customized implant abutment plays a crucial role in promoting bone remodeling and maintaining the peri-implant gingival contour. However, the biomechanical effects of abutment configuration on bone remodeling and peri-implant tissue remain unclear. This study aimed to evaluate the influence of abutment taper configurations on bone remodeling and peri-implant tissue. MATERIALS AND METHODS Five models with different abutment taper configurations (10°, 20°, 30°, 40°, and 50°) were analyzed using finite element analysis (FEA) to evaluate the biomechanical responses in peri-implant bone and the hydrostatic pressure in peri-implant tissue. RESULTS The results demonstrated that the rate of increase in bone density was similar in all models. On the other hand, the hydrostatic pressure in peri-implant gingiva revealed significantly different results. Model 10° showed the highest maximum and volume-averaged hydrostatic pressures (69.31 and 4.5 mmHg), whereas Model 30° demonstrated the lowest values (57.83 and 3.88 mmHg) with the lowest excessive pressure area. The area of excessive hydrostatic pressure decreased in all models as the degree of abutment taper increased from 10° to 30°. In contrast, Models 40° and 50° exhibited greater hydrostatic pressure concentration at the cervical region. CONCLUSION In conclusion, the abutment taper configuration had a slight effect on bone remodeling but exerted a significant effect on the peri-implant gingiva above the implant platform via hydrostatic pressure. Significant decreases in greatest and average hydrostatic pressures were observed in the peri-implant tissues of Model 30°. However, the results indicate that implant abutment tapering wider than 40° could result in a larger area of excessive hydrostatic pressure in peri-implant tissue, which could induce gingival recession.
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Affiliation(s)
- Pongsakorn Poovarodom
- Department of Prosthodontics, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Chaiy Rungsiyakull
- Department of Mechanical Engineering, Faculty of Engineering, Chiang Mai University, Muang, Chiang Mai, Thailand
| | - Jarupol Suriyawanakul
- Faculty of Engineering, Department of Mechanical Engineering, Khon Kaen University, Nai Mueang, Thailand
| | - Qing Li
- Faculty of Engineering, School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, Australia
| | - Keiichi Sasaki
- Miyagi University, Taiwa, Japan
- Graduate School of Dentistry, Division of Prosthetic Dentistry, Tohoku University, Sendai, Japan
| | - Nobuhiro Yoda
- Graduate School of Dentistry, Division of Prosthetic Dentistry, Tohoku University, Sendai, Japan
| | - Pimduen Rungsiyakull
- Department of Prosthodontics, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
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Matsumura-Matsuo M, To M, Okudera T, Matsuo M. Regeneration processes of alveolar bone and microvascular changes after the application of platelet-rich fibrin. J Oral Biosci 2023; 65:218-225. [PMID: 37277026 DOI: 10.1016/j.job.2023.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/28/2023] [Accepted: 05/29/2023] [Indexed: 06/07/2023]
Abstract
OBJECTIVES Platelet-rich fibrin (PRF) is a promising agent for bone regeneration (BR). Platelets contain several growth factors that promote angiogenesis and BR. In this study, we observed the morphology of alveolar BR. METHODS PRF (Advanced PRF: A-PRF) was prepared by extracting 10 mL of blood from each dog in a collection tube before tooth extraction. The samples were centrifuged at 200 × g for 8 min and incubated for 10 min to allow clotting. The alveolar socket on the dentition's right side was densely filled with PRF. The opposite side, which did not receive PRF, served as the control group. Different methods were used for specimen preparation and observation. Sections stained with hematoxylin and eosin were observed under a light microscope. Bone specimens were observed using stereoscopic microscopy. The resin cast models were examined using a scanning electron microscope. Moreover, bone formation ratio and height were measured. RESULTS Fourteen days postoperatively, angiogenesis and bone deposition were more advanced in the PRF group than in the control group. Thirty days postoperatively, both groups developed porous bone. In the PRF group, new bone trabeculae (BT) and a network of blood vessels were formed in the bone marrow. Ninety days postoperatively, the resin cast showed a normal bone structure with BT and bone marrow. Thick BT were observed in the PRF group. CONCLUSIONS Growth factors in PRF stimulate microcirculation and promote angiogenesis and bone deposition. The benefits of PRF include safety and increased bone formation.
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Affiliation(s)
- Maria Matsumura-Matsuo
- Department of Environmental Pathology, Kanagawa Dental University, 82 Inaoka, Yokosuka, Kanagawa, 238-8580, Japan
| | - Masahiro To
- Department of Clinical Oral Anatomy, Kanagawa Dental University, 82 Inaoka, Yokosuka, Kanagawa, 238-8580, Japan
| | - Toshimitsu Okudera
- Department of Clinical Oral Anatomy, Kanagawa Dental University, 82 Inaoka, Yokosuka, Kanagawa, 238-8580, Japan
| | - Masato Matsuo
- Department of Clinical Oral Anatomy, Kanagawa Dental University, 82 Inaoka, Yokosuka, Kanagawa, 238-8580, Japan.
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Wu C, Liu X, Zhang H, Zhang Q, Ding S, Jin S, Zheng X, Fu C, Han Q, Shen J, Xu J, Ye N, Jiang F, Wu T. Response of human periodontal ligament to orthodontic force using superb microvascular imaging. Am J Orthod Dentofacial Orthop 2022; 162:e257-e266. [PMID: 36089442 DOI: 10.1016/j.ajodo.2022.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 08/01/2022] [Accepted: 08/01/2022] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Remodeling of the periodontal ligament (PDL) during orthodontic tooth movement is closely related to the vascularity of the PDL, which has not been thoroughly investigated in humans. This study aimed to measure the width and vascular parameters of human PDL using superb microvascular imaging for the first time. METHODS Patients aged 18-25 years were selected for participation. The intervention was randomly allocated from the maxillary canines to the first molars on both sides using 50 g or 150 g of force. The width and vascular parameters of the PDL were measured using superb microvascular imaging at different time intervals (baseline, 30 minutes, and 1, 3, 7, and 14 days). RESULTS Before the intervention, the width of the PDL ranged from 0.14 to 0.25 mm, and the vascular index ranged from 9.40% to 13.54%. After applying orthodontic forces, the cervical and middle PDL widths increased. The vascular index decreased slightly in 30 minutes, decreased to a minimum value after 1 day, increased to the maximum in 3-7 days, and returned to baseline values in 14 days. The values of other vascular parameters showed similar trends. CONCLUSIONS The width and vascular parameters of the PDL changed slightly after force application, underwent changes in the period of reconstruction for 3-7 days, and eventually returned to baseline in 14 days.
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Affiliation(s)
- Chuan Wu
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | - Xiaoyu Liu
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | - Huan Zhang
- Department of Medical Ultrasound, the Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Qunyan Zhang
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | - Siqi Ding
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | - Shiyu Jin
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | - Xiuyun Zheng
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | - Chunfeng Fu
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | - Quancheng Han
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | - Jun Shen
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | - Jianguang Xu
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China
| | | | - Fan Jiang
- Department of Medical Ultrasound, the Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
| | - Tingting Wu
- Department of Orthodontics, School and Hospital of Stomatology, Anhui Medical University, Anhui Provincial Key Laboratory of Oral Diseases, Hefei, Anhui, China.
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Komaki S, Ozaki H, Takahashi SS, Wada-Takahashi S, Fushima K. Gingival blood flow before, during, and after clenching, measured by laser Doppler blood flowmeter: A pilot study. Am J Orthod Dentofacial Orthop 2021; 161:46-52. [PMID: 34509331 DOI: 10.1016/j.ajodo.2020.06.045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 06/01/2020] [Accepted: 06/01/2020] [Indexed: 11/01/2022]
Abstract
INTRODUCTION This study aimed to investigate the effects of the strong occlusal force on the hemodynamics of gingival microcirculation. METHODS Eleven adult volunteers with healthy periodontium and normal occlusion participated in this study. Using a noncontact laser Doppler flowmeter placed at the attached gingiva and the interdental papilla of the maxillary first premolar, changes in gingival blood flow (GBF) were examined during and after clenching. RESULTS When the strong occlusal pressure was applied on the maxillary first premolar by clenching, GBF in the attached gingiva on the buccal side decreased significantly compared with the resting GBF, with medians of 2.3 mL/min/100 g and 5.4 mL/min/100 g, respectively (P <0.05). After the release of the maximum clenching, GBF recovered immediately and transiently increased to a median of 2.4 mL/min/100 g, showing a significant difference to the resting GBF (P <0.05). In contrast, in the interdental papilla, no significant change in GBF was found by clenching. CONCLUSIONS Ischemia of the buccal attached gingiva associated with strong clenching may be due to compression of the vascular network of the periodontal membrane. Through reactive hyperemia resulting from the release of clenching, it is possible not only that blood flow will be restored to the tissue but that the tissue itself may be damaged by the reperfusion. During active orthodontic treatment, it is suggested that occlusal management to prevent occlusal trauma is important to avoid detrimental effects on periodontal tissues.
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Affiliation(s)
- Sayaka Komaki
- Division of Orthodontics, Department of Highly Advanced Stomatology, Graduate School of Dentistry, Kanagawa Dental University, Yokosuka, Japan
| | - Hiroya Ozaki
- Division of Orthodontics, Department of Highly Advanced Stomatology, Graduate School of Dentistry, Kanagawa Dental University, Yokosuka, Japan
| | - Shun-Suke Takahashi
- Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, Yokosuka, Japan
| | - Satoko Wada-Takahashi
- Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, Yokosuka, Japan
| | - Kenji Fushima
- Division of Orthodontics, Department of Highly Advanced Stomatology, Graduate School of Dentistry, Kanagawa Dental University, Yokosuka, Japan.
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Zhong J, Pierantoni M, Weinkamer R, Brumfeld V, Zheng K, Chen J, Swain MV, Weiner S, Li Q. Microstructural heterogeneity of the collagenous network in the loaded and unloaded periodontal ligament and its biomechanical implications. J Struct Biol 2021; 213:107772. [PMID: 34311076 DOI: 10.1016/j.jsb.2021.107772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 07/02/2021] [Accepted: 07/19/2021] [Indexed: 01/17/2023]
Abstract
The periodontal ligament (PDL) is a highly heterogeneous fibrous connective tissue and plays a critical role in distributing occlusal forces and regulating tissue remodeling. Its mechanical properties are largely determined by the extracellular matrix, comprising a collagenous fiber network interacting with the capillary system as well as interstitial fluid containing proteoglycans. While the phase-contrast micro-CT technique has portrayed the 3D microscopic heterogeneity of PDL, the topological parameters of its network, which is crucial to understanding the multiscale constitutive behavior of this tissue, has not been characterized quantitatively. This study aimed to provide new understanding of such microscopic heterogeneity of the PDL with quantifications at both tissue and collagen network levels in a spatial manner, by combining phase-contrast micro-CT imaging and a purpose-built image processing algorithm for fiber analysis. Both variations within a PDL and among the PDL with different shapes, i.e. round-shaped and kidney-shaped PDLs, are described in terms of tissue thickness, fiber distribution, local fiber densities, and fiber orientation (namely azimuthal and elevation angles). Furthermore, the tissue and collagen fiber network responses to mechanical loading were evaluated in a similar manner. A 3D helical alignment pattern was observed in the fiber network, which appears to regulate and adapt a screw-like tooth motion under occlusion. The microstructural heterogeneity quantified here allows development of sample-specific constitutive models to characterize the PDL's functional and pathological loading responses, thereby providing a new multiscale framework for advancing our knowledge of this complex limited mobility soft-hard tissue interface.
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Affiliation(s)
- Jingxiao Zhong
- School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Sydney, Australia
| | - Maria Pierantoni
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel; Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - Richard Weinkamer
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Vlad Brumfeld
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Keke Zheng
- School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Sydney, Australia; College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, UK
| | - Junning Chen
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, UK
| | - Michael V Swain
- School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Sydney, Australia
| | - Steve Weiner
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Qing Li
- School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Sydney, Australia.
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Yamamoto R, Amano K, Takahashi SW, To M, Takahashi S, Matsuo M. Changes in the microcirculation in periodontal tissue due to experimental peri-implantitis. J Oral Biosci 2021; 63:153-160. [PMID: 33746071 DOI: 10.1016/j.job.2021.03.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 03/04/2021] [Accepted: 02/20/2021] [Indexed: 01/24/2023]
Abstract
OBJECTIVES Peri-implantitis causes dislodgement of dental implants due to inflammation in the peri-implant tissue. The microcirculation in the periodontal tissue undergoes morphological and physiological changes due to inflammation. The immune mechanism of peri-implantitis differs from that of periodontitis. In this study, we examined the changes in the microcirculation in the peri-implant tissue with experimentally induced inflammation, using morphological and physiological techniques. METHODS Six beagle dogs were used in the experiment. After extracting both mandibular premolars, three titanium screw implants were inserted on each side of the mandibular jaw. Dental floss was placed on the right side for 90 days in the study group but not in the control group. Microvascular resin cast models were created, and morphological changes were observed using scanning electron microscopy. Periodontal blood flow was measured using laser Doppler flowmetry. RESULTS Ninety days after induction of inflammation, bone resorption was observed around the implant body. Osseointegration was impaired, and a gap at the implant-bone interface was observed. The resin cast models showed that inflamed gingival blood vessels had invaded the bone marrow through the resorbed apical margin of the alveolar bone. Analysis of the physiological data obtained using laser Doppler flowmetry showed a significant increase in blood flow around the implants with experimentally induced inflammation. CONCLUSIONS Significant morphological and physiological changes occur in the gingival microcirculation of peri-implant tissue due to inflammation. Evaluating the vasculature and blood flow in the tissue surrounding the site of peri-implantitis may be helpful for pathologic analysis in clinical settings.
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Affiliation(s)
- Reiko Yamamoto
- Department of Oral Science, Kanagawa Dental University, Graduate School of Dentistry, Japan
| | - Kaori Amano
- Department of Oral Science, Kanagawa Dental University, Graduate School of Dentistry, Japan
| | - Satoko-Wada Takahashi
- Department of Oral Science, Kanagawa Dental University, Graduate School of Dentistry, Japan
| | - Masahiro To
- Department of Oral Science, Kanagawa Dental University, Graduate School of Dentistry, Japan
| | - Shunsuke Takahashi
- Department of Oral Science, Kanagawa Dental University, Graduate School of Dentistry, Japan
| | - Masato Matsuo
- Department of Oral Science, Kanagawa Dental University, Graduate School of Dentistry, Japan.
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To M, Matsuo M, Wada-Takahashi S, Sugiyama S, Tamaki K, Takahashi SS. Microcirculation changes in gingival tissue after ultrasonic tooth preparation in beagle dogs. J Appl Oral Sci 2020; 28:e20190145. [PMID: 32049132 PMCID: PMC6999118 DOI: 10.1590/1678-7757-2019-0145] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 08/22/2019] [Indexed: 12/26/2022] Open
Abstract
OBJECTIVE Ultrasonic wave technology is widely used during dental treatments. We previously demonstrated that this method protects the gingival tissue. However, the physiological change on the gingival microvasculature caused by this method remains unclear. The aim of this study was to investigate the relationship between the morphological and physiological effects on gingival microcirculation when preparing teeth, using the conventional dental turbine or ultrasonic method. METHODOLOGY The lower premolar teeth of beagle dogs were prepared along the gingival margin by using a dental turbine or ultrasonic wave instrument. Gingival vasculature changes were investigated using scanning electron microscopy for corrosion resin casts. Gingival blood flow at the preparation site was determined simultaneously by laser Doppler flowmetry. These assessments were performed immediately (Day 0), at 7 days and 30 days after tooth preparation. RESULTS At day 0, in the turbine group, blood vessels were destroyed and some resin leaked. Furthermore, gingival blood flow at the site was significantly increased. In contrast, the ultrasonic group demonstrated nearly normal vasculature and gingival blood flow similar to the non-prepared group for 30 days after preparation. No significant alterations occurred in gingival circulation 30 days after either preparation; however, the turbine group revealed obvious morphological changes. CONCLUSIONS Based on multiple approach analyses, this study demonstrated that ultrasonic waves are useful for microvascular protection in tooth preparation. Compared with a dental turbine, ultrasonic wave instruments caused minimal damage to gingival microcirculation. Tooth preparation using ultrasonic wave instruments could be valuable for protecting periodontal tissue.
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Affiliation(s)
- Masahiro To
- Kanagawa Dental University, Graduate School of Dentistry, Department of Oral Science, Kanagawa, Japan
| | - Masato Matsuo
- Kanagawa Dental University, Graduate School of Dentistry, Department of Oral Science, Kanagawa, Japan
| | - Satoko Wada-Takahashi
- Kanagawa Dental University, Graduate School of Dentistry, Department of Oral Science, Kanagawa, Japan
| | - Shuta Sugiyama
- Kanagawa Dental University, Graduate School of Dentistry, Department of Oral Science, Kanagawa, Japan
| | - Katsushi Tamaki
- Kanagawa Dental University, Graduate School of Dentistry, Department of Critical Care Medicine and Dentistry, Kanagawa, Japan
| | - Shun-Suke Takahashi
- Kanagawa Dental University, Graduate School of Dentistry, Department of Oral Science, Kanagawa, Japan
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Abstract
Teeth are exposed to hundreds of oral bacteria and also challenged by the mastication forces; because teeth are situated in oral cavity, the entrance of the digestive tract, and penetrates through the oral epithelium. The periodontal ligament is a noncalcified tissue that possesses abundant blood vessels, which exist between tooth root and alveolar bone. The ligament is thought to play an important role in absorbing the impact of mastication, in the maintenance of periodontal homeostasis, and in periodontal wound healing. We succeeded in isolating mesenchymal stem cells (MSCs), so-called periodontal stem cells (PDLSCs), with self-renewability and multipotency from the periodontal ligament. We also demonstrated that PDLSCs share some cell surface markers with pericytes and that PDLSCs distribute themselves to stay with the endothelial cell networks and that PDLSCs maintain the endothelial cell networks when added to endothelial cell network formation systems. Pericytes are located in the proximity of microvascular endothelial cells and thought to stabilize and supply nutrients to blood vessels. Recently, it was also reported that pericytes possess multipotency and can be the source of tissue stem cells and/or progenitor cells. This review explores the distinctive features of the periodontal ligament tissue and PDLSCs as well as the puzzling similarities between PDLSCs and pericytes.
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Azaripour A, Lagerweij T, Scharfbillig C, Jadczak AE, Swaan BVD, Molenaar M, Waal RVD, Kielbassa K, Tigchelaar W, Picavet DI, Jonker A, Hendrikx EML, Hira VVV, Khurshed M, Noorden CJFV. Three-dimensional histochemistry and imaging of human gingiva. Sci Rep 2018; 8:1647. [PMID: 29374186 PMCID: PMC5785975 DOI: 10.1038/s41598-018-19685-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 01/08/2018] [Indexed: 11/09/2022] Open
Abstract
In the present study, 3D histochemistry and imaging methodology is described for human gingiva to analyze its vascular network. Fifteen human gingiva samples without signs of inflammation were cleared using a mixture of 2-parts benzyl benzoate and 1-part benzyl alcohol (BABB), after being immunofluorescently stained for CD31, marker of endothelial cells to visualize blood vessels in combination with fluorescent DNA dyes. Samples were imaged in 3D with the use of confocal microscopy and light-sheet microscopy and image processing. BABB clearing caused limited tissue shrinkage 13 ± 7% as surface area and 24 ± 1% as volume. Fluorescence remained intact in BABB-cleared gingiva samples and light-sheet microscopy was an excellent tool to image gingivae whereas confocal microscopy was not. Histochemistry on cryostat sections of gingiva samples after 3D imaging validated structures visualized in 3D. Three-dimensional images showed the vascular network in the stroma of gingiva with one capillary loop in each stromal papilla invading into the epithelium. The capillary loops were tortuous with structural irregularities that were not apparent in 2D images. It is concluded that 3D histochemistry and imaging methodology described here is a promising novel approach to study structural aspects of human gingiva in health and disease.
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Affiliation(s)
- Adriano Azaripour
- Department of Operative Dentistry, University Medical Center of the Johannes Gutenberg University Mainz, Augustusplatz 2, Mainz, 55131, Germany. .,Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands.
| | - Tonny Lagerweij
- Department of Neurosurgery, Neuro-oncology Research Group, VU University Medical Center, Cancer Center Amsterdam, Room 3.36, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands
| | - Christina Scharfbillig
- Department of Operative Dentistry, University Medical Center of the Johannes Gutenberg University Mainz, Augustusplatz 2, Mainz, 55131, Germany
| | - Anna Elisabeth Jadczak
- Department of Operative Dentistry, University Medical Center of the Johannes Gutenberg University Mainz, Augustusplatz 2, Mainz, 55131, Germany
| | - Britt van der Swaan
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Manon Molenaar
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Rens van der Waal
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Karoline Kielbassa
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Wikky Tigchelaar
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Daisy I Picavet
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Ard Jonker
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Esther M L Hendrikx
- Molecular Cell Biology and Immunology, VU University Medical Center, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands
| | - Vashendriya V V Hira
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Mohammed Khurshed
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Cornelis J F Van Noorden
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
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11
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Matsuo M, Okudera T, Takahashi SS, Wada-Takahashi S, Maeda S, Iimura A. Microcirculation alterations in experimentally induced gingivitis in dogs. Anat Sci Int 2016; 92:112-117. [PMID: 26830431 DOI: 10.1007/s12565-015-0324-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 12/18/2015] [Indexed: 11/24/2022]
Abstract
The present study aimed to morphologically examine the gingival microvascular network using a microvascular resin cast (MRC) technique, and to investigate how inflammatory disease functionally affects gingival microcirculation using laser Doppler flowmetry (LDF). We used four beagle dogs with healthy periodontal tissue as experimental animals. To cause periodontal inflammation, dental floss was placed around the cervical neck portions of the right premolars. The unmanipulated left premolars served as controls, and received plaque control every 7 days. After 90 days, gingivitis was induced in the experimental side, while the control side maintained healthy gingiva. To perform morphological examinations, we used an MRC method involving the injection of low-viscosity synthetic resin into the blood vessels, leading to peripheral soft-tissue dissolution and permitting observation of the bone, teeth, and vascular cast. Gingival blood flow was estimated using an LDF meter. The control gingival vasculature showed hairpin-loop-like networks along the tooth surface. The blood vessels had diameters of 20-40 μm and were regularly arranged around the cervical portion. On the other hand, the vasculature in the experimental group was twisted and gathered into spiral forms, with blood vessels that had uneven surfaces and smaller diameters of 8-10 μm. LDF revealed reduced gingival blood flow in the group with experimentally induced gingivitis compared to controls. The actual measurements of gingival blood flow by LDF were in agreement with the alterations that would be expected based on the gingivitis-induced morphological alterations observed with the MRC technique.
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Affiliation(s)
- Masato Matsuo
- Division of Dental Anatomy, Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan.
| | - Toshimitsu Okudera
- Division of Dental Anatomy, Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan
| | - Shun-Suke Takahashi
- Division of Circulation Control for Dentistry, Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan
| | - Satoko Wada-Takahashi
- Division of Circulation Control for Dentistry, Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan
| | - Shingo Maeda
- Division of Dental Anatomy, Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan
| | - Akira Iimura
- Division of Dental Anatomy, Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan
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12
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Kaku M, Rosales Rocabado JM, Kitami M, Ida T, Akiba Y, Yamauchi M, Uoshima K. Mechanical Loading Stimulates Expression of Collagen Cross-Linking Associated Enzymes in Periodontal Ligament. J Cell Physiol 2015; 231:926-33. [DOI: 10.1002/jcp.25184] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 09/03/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Masaru Kaku
- Division of Bioprosthodontics; Niigata University Graduate School of Medical and Dental Sciences; Niigata Japan
| | | | - Megumi Kitami
- Division of Bioprosthodontics; Niigata University Graduate School of Medical and Dental Sciences; Niigata Japan
| | - Takako Ida
- Division of Bioprosthodontics; Niigata University Graduate School of Medical and Dental Sciences; Niigata Japan
| | - Yosuke Akiba
- Division of Bioprosthodontics; Niigata University Graduate School of Medical and Dental Sciences; Niigata Japan
| | - Mitsuo Yamauchi
- North Carolina Oral Health Institute; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Katsumi Uoshima
- Division of Bioprosthodontics; Niigata University Graduate School of Medical and Dental Sciences; Niigata Japan
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13
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Townsend D, D'Aiuto F, Deanfield J. Preliminary study of video imaging of blood vessels in tissues lining the gingival sulcus in periodontally healthy individuals. J Periodontal Res 2013; 49:670-9. [DOI: 10.1111/jre.12150] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2013] [Indexed: 12/23/2022]
Affiliation(s)
- D. Townsend
- Vascular Physiology Unit; University College London Institute of Cardiovascular Science; London UK
| | - F. D'Aiuto
- Periodontology Unit, Department of Clinical Research; UCL Eastman Dental Institute; London UK
| | - J. Deanfield
- Vascular Physiology Unit; University College London Institute of Cardiovascular Science; London UK
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14
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Yoshida S, Noguchi K, Imura K, Miwa Y, Sunohara M, Sato I. A morphological study of the blood vessels associated with periodontal probing depth in human gingival tissue. Okajimas Folia Anat Jpn 2012; 88:103-9. [PMID: 22519069 DOI: 10.2535/ofaj.88.103] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Gingival tissues in human cadavers were examined the blood vessel diameter in the depths of the gingival pockets such as three groups: gingiva adjacent to a sulcus of 2 mm (Group 1); gingiva adjacent to a 2-4-mm sulcus (Group 2); and gingiva adjacent to a sulcus of > 4 mm (Group 3). A meaningful significant difference was seen observed in gingival pocket side, intermediate and outer layer side regions of the gingiva. A meaningful significant difference was seen found in intermediate part and the outer layer of the gingiva in Group 3. Other gingival biopsies were performed on a human body donation specimen to examine CD-31 positive endothelial cells of blood vessels by an immnohistochemical method. Our results suggest that the periodontal probing depth reflect the blood vessel organization of human gingival tissue.
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Affiliation(s)
- Shunji Yoshida
- Department of Anatomy, School of Life Dentistry at Tokyo, Nippon Dental University 1-9-20 Fujimi, Chiyoda-ku, Tokyo 102-8159, Japan
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15
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Implications of cultured periodontal ligament cells for the clinical and experimental setting: a review. Arch Oral Biol 2011; 56:933-43. [PMID: 21470594 DOI: 10.1016/j.archoralbio.2011.03.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2010] [Revised: 02/08/2011] [Accepted: 03/06/2011] [Indexed: 01/17/2023]
Abstract
The periodontal ligament (PDL) is a key contributor to the process of regeneration of the periodontium. The heterogeneous nature of the PDL tissue, its development during early adulthood, and the different conditions to which the PDL tissue is exposed to in vivo impart on the PDL unique characteristics that may be of consequence during its cultivation in vitro. Several factors affecting the in vivo setting influence the behaviour of PDL fibroblasts in culture. The purpose of this review is to address distinct factors that influence the behaviour of PDL fibroblasts in culture -in vivo-in vitro transitions, cell identification/isolation markers, primary PDL cultures and cell lines, tooth-specific factors, and donor-specific factors. Based on the reviewed studies, the authors recommendations include the use of several identification markers to confirm cell identity, use of primary cultures at early passage to maintain unique PDL heterogeneic characteristics, and noting donor conditions such as age, systemic health status, and tooth health status. Continued efforts will expand our understanding of the in vitro and in vivo behaviour of cells, with the goal of orchestrating optimal periodontal regeneration. This understanding will lead to improved evidence-based rationales for more individualized and predictable periodontal regenerative therapies.
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16
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Bergomi M, Cugnoni J, Wiskott HWA, Schneider P, Stampanoni M, Botsis J, Belser UC. Three-dimensional morphometry of strained bovine periodontal ligament using synchrotron radiation-based tomography. J Anat 2010; 217:126-34. [PMID: 20557399 DOI: 10.1111/j.1469-7580.2010.01250.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The periodontal ligament (PDL) is a highly vascularized soft connective tissue. Previous studies suggest that the viscous component of the mechanical response may be explained by the deformation-induced collapse and expansion of internal voids (i.e. chiefly blood vessels) interacting with liquids (i.e. blood and interstitial fluids) flowing through the pores. In the present work we propose a methodology by means of which the morphology of the PDL vascular plexus can be monitored at different levels of compressive and tensile strains. To this end, 4-mm-diameter cylindrical specimens, comprising layers of bone, PDL and dentin covered by cementum, were strained at stretch ratios ranging from lambda = 0.6 to lambda = 1.4 and scanned using synchrotron radiation-based computer tomography. It was concluded that: (1) the PDL vascular network is layered in two distinct planes of blood vessels (BVs): an inner layer (close to the tooth), in which the BVs run in apico-coronal direction, and an outer layer (close to the alveolar bone), in which the BVs distribution is more diffuse; (2) during tension and compression, the porosity tissue is kept fairly constant; (3) mechanical straining induces important changes in BV diameters, possibly modifying the permeability of the PDL and thus contributing to the viscous component of the viscoelastic response observed under compressive forces.
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Affiliation(s)
- Marzio Bergomi
- Laboratoire de mécanique appliquée et d'analyse de fiabilité, Ecole polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
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17
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Masset A, Staszyk C, Gasse H. The blood vessel system in the periodontal ligament of the equine cheek teeth--part I: The spatial arrangement in layers. Ann Anat 2007; 188:529-33. [PMID: 17140145 DOI: 10.1016/j.aanat.2006.06.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Corrosion casts of blood vessels in the periodontium of cheek teeth from eight horses were observed three-dimensionally with a dissection microscope. Selected specimens were examined in a scanning electron microscope. Periodontal blood vessels communicated with those from the gingiva, the alveolar bone, and the apical region. In the upper jaw, there were anastomoses with the blood vessels of the mucosa of the maxillary sinus. The periodontal vascular system was organized in two or three layers. The peripheral layer was mainly composed of large venules, the inner one consisted of capillaries. In the intermediate layer, blood vessels were post-capillary venules. This layer was developed only in horses under 10 years of age. In all layers the vascular orientation was mainly occluso-apical, this was defined as the standard pattern. There were many variations displayed in different courses of certain blood vessels. The vascular organization is discussed with regard to the specialized functions of the periodontal ligament (PDL). The wide vessels of the outer layer are thought to play a mechanical role as part of a shock absorbing system. The capillaries of the inner layer meet nutritional requirements. The disappearance of the intermediate layer in horses older than 10 years is taken as an adaptation to the remodelling of the PDL. Modifications in the standard pattern of vascular arrangements are also interpreted as adaptations to life-long changes in the periodontal space. Anastomoses between the periodontal vasculature and the blood vessels of the maxillary sinus indicate that periodontal disease may be transferred into the sinus.
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Affiliation(s)
- Alexandra Masset
- Institute of Anatomy, University of Veterinary Medicine Hannover, Bischofsholer Damm 15, D-30173 Hannover, Germany
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18
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Traini T, Assenza B, San Roman F, Thams U, Caputi S, Piattelli A. Bone microvascular pattern around loaded dental implants in a canine model. Clin Oral Investig 2006; 10:151-6. [PMID: 16607541 DOI: 10.1007/s00784-006-0043-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2005] [Accepted: 03/01/2006] [Indexed: 12/19/2022]
Abstract
The vascularity of the implant bed is a very important parameter in both bone formation and maintenance after dental implants insertion. The relationship between bone and vessels network organization is still unknown. The aim of this study was to investigate the three-dimensional bone vascular canals of the peri-implant bone after loading. A total of ten implants with sandblasted and acid-etched surface were placed in the mandible of a beagle dog. Three months later, the implants were connected and loaded. The dog was killed after 12 months. The specimens were embedded and processed for scanning electron microscopy (SEM) analysis. After a 1-year loading period, a very intricate vessel network could be seen around the implants. The vessels, with neighbouring soft tissues, were round in shape and showed a lot of anastomoses with a mesh-like appearance. They ran circularly around the dental implant. In the bone, the majority of the vessels appeared to ran parallel to the mandibular canal. After a 1-year loading period, the peri-implant bone vasculature looked like a mesh that surrounded the implants. Nevertheless, the presence of many thick vessels inside the peri-implant crestal bone indicates a high metabolic need and also a different bone organization, as no osteons were noted. The crater-like bone loss around the marginal part of the implant could be related to the microvasculature "strain". A high strain level could continuously activate the osteocyte-vessel syncytium, producing a net bone loss.
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Affiliation(s)
- Tonino Traini
- Department of Applied Sciences of Oral and Dental Diseases, School of Dentistry, University G.d'Annunzio, via dei Vestini 31, 66100 Chieti, Italy
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19
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Jing X, Shuling G, Ying L. Environmental scanning electron microscopy observation of the ultrastructure of Demodex. Microsc Res Tech 2005; 68:284-9. [PMID: 16315233 DOI: 10.1002/jemt.20253] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In this study, numbers of Demodex of hair follicles and sebaceous glands were prepared and the ultrastructure (especially the mouthparts) of Demodex was observed firstly with environmental scanning electron microscopy (ESEM). The most suitable treatment methods and optimal environmental condition for observing the genus samples were found. The samples were washed with detergent and rinsed with distilled water, and then were taken to the specimen stage, on which there was carbon adhesive tape, using special tools. When the temperature was at 5 degrees C and chamber pressure at 5 mbar respectively, the surface of the samples could be fully imaged without covering water or dehydration. The sample surfaces were plump and clear without postmortem changes and charging artifacts. Detailed information about each part of Demodex was observed by ESEM, and clear three-dimensional images were recorded. The mouthparts of D. folliculorum were composed of a complex set of structures, which included a round oral opening, a sharp oral needle, and a special hypostome that looked like a longitudinal spindle in the central position. On the end segment of palpus, there were seven strong palpal claws located on each side of the mouthparts. D. folliculorum had special piercing mouthparts, while the mouthparts of D. brevis were a simpler structure. We could not observe the oral needle of D. brevis, and there were only five pairs of palpal claws on the end segment of palpus. The offensive organs of Demodex resulted in its pathogenic effects. After studying hundreds of Demodex, we identified both female and male species of D. folliculorum, but only females of D. brevis in our sample.
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Affiliation(s)
- Xu Jing
- Instrumental Analysis Center, Shandong Institute of Light Industry, Jinan 250100, People's Republic of China.
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