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Ren J, Li Z, Liu W, Fan Y, Qi L, Li S, Kong C, Zou H, Liu Z. Demineralized bone matrix for repair and regeneration of maxillofacial defects: A narrative review. J Dent 2024; 143:104899. [PMID: 38428719 DOI: 10.1016/j.jdent.2024.104899] [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: 01/08/2024] [Revised: 02/14/2024] [Accepted: 02/23/2024] [Indexed: 03/03/2024] Open
Abstract
OBJECTIVES Demineralized bone matrix (DBM) is a well-established bone graft material widely accepted by dentists and the public for its favorable osteoconductivity and osteoinductive potential. This article aimed to provide a narrative review of the current therapeutic applications and limitations of DBM in maxillofacial bone defects. STUDY SELECTION, DATA, AND SOURCES Randomized controlled trials, prospective or retrospective clinical studies, case series and reports, and systematic reviews. MEDLINE, PubMed, and Google Scholar were searched using keywords. CONCLUSIONS Some evidence supported the therapeutic application of DBM in periodontal intrabony defects, maxillary sinus lifts, ridge preservation, ridge augmentation, alveolar cleft repair, orthognathic surgery, and other regional maxillofacial bone defects. However, the limitations of DBM should be considered when using it, including potential low immunogenicity, instability of osteoinductive potential, handling of the graft material, and patient acceptance. CLINICAL SIGNIFICANCE With the increasing demand for the treatment of maxillofacial bone defects, DBM is likely to play a greater role as a promising bone graft material. Safe and effective combination treatment strategies and how to maintain a stable osteoinductive potential will be the future challenges of DBM research.
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Affiliation(s)
- Jiwei Ren
- Hospital of Stomatology, Jilin University, China
| | - Zhiwei Li
- Hospital of Stomatology, Jilin University, China
| | - Wantong Liu
- Hospital of Stomatology, Jilin University, China
| | - Yixin Fan
- Hospital of Stomatology, Jilin University, China
| | - Le Qi
- Hospital of Stomatology, Jilin University, China
| | - Sining Li
- Hospital of Stomatology, Jilin University, China
| | - Chen Kong
- Hospital of Stomatology, Jilin University, China
| | - He Zou
- Hospital of Stomatology, Jilin University, China
| | - Zhihui Liu
- Hospital of Stomatology, Jilin University, China.
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Al Deeb M, Aldosari AA, Anil S. Osseointegration of Tantalum Trabecular Metal in Titanium Dental Implants: Histological and Micro-CT Study. J Funct Biomater 2023; 14:355. [PMID: 37504850 PMCID: PMC10382015 DOI: 10.3390/jfb14070355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 06/26/2023] [Accepted: 07/02/2023] [Indexed: 07/29/2023] Open
Abstract
This study aimed to investigate the impact of the Tantalum Trabecular Metal dental implant design on implant stability and the process of osseointegration following its placement in the rabbit femoral condyle. The subjects for the experiment consisted of 10 New Zealand white rabbits. Twenty implants, comprising 10 Trabecular Metal (TM) and 10 Traditional Screw Vent (TSV) implants, were placed into the femoral condyles of these rabbits. The implant type was alternated based on a random sequence. Following a healing period of 8 weeks, the implants were retrieved for further analysis using micro-computed tomography (micro-CT), histological studies, and histomorphometry evaluations. The Bone-to-Implant Contact (BIC) ratio and the Bone Volume (BV) percentage in the region of interest were subsequently assessed. The BIC and BV values between TM and TSV implants were compared using the Student t-test. The TM implants exhibited significantly greater BIC and BV scores. In particular, the BIC percentage was recorded as 57.9 ± 6.5 for the TM implants, as opposed to 47.6 ± 8 for the TSV implants. Correspondingly, the BV percentage was 57 ± 7.3 for the TM implants and 46.4 ± 7.4 for the TSV implants. The bone volume percentage measured using micro-CT evaluation was 89.1 ± 8.7 for the TM implants and 79.1 ± 8.6 for the TSV implants. Given the observed results, it is plausible to suggest that the bone growth surrounding the tantalum mesh could have improved the integration of the bone and facilitated its ingrowth into the TM implant.
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Affiliation(s)
- Modhi Al Deeb
- Department of Prosthetic Dental Science, College of Dentistry, King Saud University, P.O. Box 60169, Riyadh 11545, Saudi Arabia
| | - Abdullah AlFarraj Aldosari
- Department of Prosthetic Dental Science, College of Dentistry, King Saud University, P.O. Box 60169, Riyadh 11545, Saudi Arabia
| | - Sukumaran Anil
- Department of Dentistry, Oral Health Institute, Hamad Medical Corporation, Doha P.O. Box 3050, Qatar
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Huang G, Pan ST, Qiu JX. The Clinical Application of Porous Tantalum and Its New Development for Bone Tissue Engineering. MATERIALS (BASEL, SWITZERLAND) 2021; 14:2647. [PMID: 34070153 PMCID: PMC8158527 DOI: 10.3390/ma14102647] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 05/06/2021] [Accepted: 05/13/2021] [Indexed: 12/13/2022]
Abstract
Porous tantalum (Ta) is a promising biomaterial and has been applied in orthopedics and dentistry for nearly two decades. The high porosity and interconnected pore structure of porous Ta promise fine bone ingrowth and new bone formation within the inner space, which further guarantee rapid osteointegration and bone-implant stability in the long term. Porous Ta has high wettability and surface energy that can facilitate adherence, proliferation and mineralization of osteoblasts. Meanwhile, the low elastic modulus and high friction coefficient of porous Ta allow it to effectively avoid the stress shield effect, minimize marginal bone loss and ensure primary stability. Accordingly, the satisfactory clinical application of porous Ta-based implants or prostheses is mainly derived from its excellent biological and mechanical properties. With the advent of additive manufacturing, personalized porous Ta-based implants or prostheses have shown their clinical value in the treatment of individual patients who need specially designed implants or prosthesis. In addition, many modification methods have been introduced to enhance the bioactivity and antibacterial property of porous Ta with promising in vitro and in vivo research results. In any case, choosing suitable patients is of great importance to guarantee surgical success after porous Ta insertion.
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Affiliation(s)
| | | | - Jia-Xuan Qiu
- Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Nanchang University, Nanchang 330006, China; (G.H.); (S.-T.P.)
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The progress on physicochemical properties and biocompatibility of tantalum-based metal bone implants. SN APPLIED SCIENCES 2020. [DOI: 10.1007/s42452-020-2480-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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Talmazov G, Veilleux N, Abdulmajeed A, Bencharit S. Finite element analysis of a one-piece zirconia implant in anterior single tooth implant applications. PLoS One 2020; 15:e0229360. [PMID: 32092128 PMCID: PMC7039452 DOI: 10.1371/journal.pone.0229360] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 02/04/2020] [Indexed: 11/19/2022] Open
Abstract
This study evaluated the von Mises stress (MPa) and equivalent strain occurring around monolithic yttria-zirconia (Zir) implant using three clinically simulated finite element analysis (FEA) models for a missing maxillary central incisor. Two unidentified patients' cone-beam computed tomography (CBCT) datasets with and without right maxillary central incisor were used to create the FEA models. Three different FEA models were made with bone structures that represent a healed socket (HS), reduced bone width edentulous site (RB), and immediate extraction socket with graft (EG). A one-piece abutment-implant fixture mimicking Straumann Standard Plus tissue level RN 4.1 X 11.8mm, for titanium alloy (Ti) and Zir were modeled. 178 N oblique load and 200 N vertical load were used to simulate occlusal loading. Von Mises stress and equivalent strain values for around each implant model were measured. Within the HS and RB models the labial-cervical region in the cortical bone exhibited highest stress, with Zir having statistically significant lower stress-strain means than Ti in both labial and palatal aspects. For the EG model the labial-cervical area had no statistically significant difference between Ti and Zir; however, Zir performed better than Ti against the graft. FEA models suggest that Ti, a more elastic material than Zir, contributes to the transduction of more overall forces to the socket compared to Zir. Thus, compared to Ti implants, Zir implants may be less prone to peri-implant bone overloading and subsequent bone loss in high stress areas especially in the labial-cervical region of the cortical bone. Zir implants respond to occlusal loading differently than Ti implants. Zir implants may be more favorable in non-grafted edentulous or immediate extraction with grafting.
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Affiliation(s)
- Georgi Talmazov
- Department of General Practice, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Nathan Veilleux
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Aous Abdulmajeed
- Department of General Practice, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Sompop Bencharit
- Department of General Practice, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, Virginia, United States of America
- Department of Oral & Maxillofacial Surgery, School of Dentistry Commonwealth University, Richmond, Virginia, United States of America
- * E-mail:
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Li J, Jansen JA, Walboomers XF, van den Beucken JJ. Mechanical aspects of dental implants and osseointegration: A narrative review. J Mech Behav Biomed Mater 2019; 103:103574. [PMID: 32090904 DOI: 10.1016/j.jmbbm.2019.103574] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 09/23/2019] [Accepted: 11/29/2019] [Indexed: 12/28/2022]
Abstract
With the need of rapid healing and long-term stability of dental implants, the existing Ti-based implant materials do not meet completely the current expectation of patients. Low elastic modulus Ti-alloys have shown superior biocompatibility and can achieve comparable or even faster bone formation in vivo at the interface of bone and the implant. Porous structured Ti alloys have shown to allow rapid bone ingrowth through their open structure and to achieve anchorage with bone tissue by increasing the bone-implant interface area. In addition to the mechanical properties of implant materials, the design of the implant body can be used to optimize load transfer and affect the ultimate results of osseointegration. The aim of this narrative review is to define the mechanical properties of dental implants, summarize the relationship between implant stability and osseointegration, discuss the effect of metallic implant mechanical properties (e.g. stiffness and porosity) on the bone response based on existing in vitro and in vivo information, and analyze load transfer through mechanical properties of the implant body. This narrative review concluded that although several studies have presented the advantages of low elastic modulus or high porosity alloys and their effect on osseointegration, further in vivo studies, especially long-term observational studies are needed to justify these novel materials as a replacement for current Ti-based implant materials.
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Affiliation(s)
- Jinmeng Li
- Department of Biomaterials, Radboudumc, P.O. Box 9101, 6500, Nijmegen, HB, the Netherlands
| | - John A Jansen
- Department of Biomaterials, Radboudumc, P.O. Box 9101, 6500, Nijmegen, HB, the Netherlands
| | - X Frank Walboomers
- Department of Biomaterials, Radboudumc, P.O. Box 9101, 6500, Nijmegen, HB, the Netherlands
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Using Er:YAG laser to remove lithium disilicate crowns from zirconia implant abutments: An in vitro study. PLoS One 2019; 14:e0223924. [PMID: 31689289 PMCID: PMC6830778 DOI: 10.1371/journal.pone.0223924] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 10/01/2019] [Indexed: 01/04/2023] Open
Abstract
Background When implants are restored with cement-retained restorations, prosthetic retrievability can be difficult and often requires sectioning using rotary instruments. Sometimes repeated removals of a cement-retained implant crown are needed such as for treatment of peri-implantitis or immediate implant provisionalization. The purpose of this study was to evaluate the effect of erbium-doped yttrium aluminum garnet (Er:YAG) laser as a non-invasive treatment modality to remove lithium disilicate crowns from zirconia implant abutments following long-term cementation, repetitive debonding and re-cementation, and short-term retrieval. Material and methods Twenty identical lithium disilicate crowns were cemented onto zirconia prefabricated abutments using composite resin cement. Ten cemented crowns were removed at 48 hours after cementation as a short-term group (ST), while another 10 were removed 6 months after cementation as a long-term group (LT). To mimicking repetitive recementation and retrieval, the LT crowns were then recemented and removed after 48 hours as a long-term recemention (LTR) group. The LTR crowns were then again recemented and removed after 48 hours as a long-term repeated recemention (LTRR) group. Er:YAG laser was used to facilitate the retrieval of these crowns. recorded and analyzed using ANOVA and t-test. The surfaces of the crown and the abutment were further examined using light microscopy and scanning electron microscopy (SEM). Temperature changes of the abutment and crown upto 10 minutes were also measured and statistically analyzed (paired t-test). Results The average times of crown removal from zirconia abutments were 4 minutes (min) and 42 second (sec) in LT to 3 min 24 sec in LTR, and 3 min 12 sec in LTRR and ST groups. LTR took the longest time to remove, statistically (ANOVA and t-test, p < .001). No statistical differences were observed among the removal times of LTR, LTRR, and ST groups (t-test, p = .246, .246 and 1). SEM examination of the material surface showed no visual surface damaging from treatment with Er:YAG laser. The temperatures during irradiation ranged from 18.4°C to 20°C and 22.2°C to 24.5°C (Paired t-test, p < .0001) for the abutment and the crown during irradiation from 1 min to 10 mins. Conclusions Long-term cementation can increase time in lithium disilicate crown removal from zirconia abutment using Er:YAG. Er:YAG laser is a non-invasive tool to remove cement-retained implant prostheses and should be considered as a viable alternative to rotary instruments.
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Yeung M, Abdulmajeed A, Carrico CK, Deeb GR, Bencharit S. Accuracy and precision of 3D-printed implant surgical guides with different implant systems: An in vitro study. J Prosthet Dent 2019; 123:821-828. [PMID: 31653399 DOI: 10.1016/j.prosdent.2019.05.027] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 04/23/2019] [Accepted: 05/21/2019] [Indexed: 11/15/2022]
Abstract
STATEMENT OF PROBLEM Implant guided surgery systems promise implant placement accuracy and precision beyond straightforward nonguided surgery. Recently introduced in-office stereolithography systems allow clinicians to produce implant surgical guides themselves. However, different implant designs and osteotomy preparation protocols may produce accuracy and precision differences among the different implant systems. PURPOSE The purpose of this in vitro study was to measure the accuracy and precision of 3 implant systems, Tapered Internal implant system (BioHorizons) (BH), NobelReplace Conical (Nobel Biocare) (NB), and Tapered Screw-Vent (Zimmer Biomet) (ZB) when in-office fabricated surgical guides were used. MATERIAL AND METHODS A cone beam computed tomography (CBCT) data set of an unidentified patient missing a maxillary right central incisor and intraoral scans of the same patient were used as a model. A software program (3Shape Implant Studio) was used to plan the implant treatment with the 3 implant systems. Three implant surgical guides were fabricated by using a 3D printer (Form 2), and 30 casts were printed. A total of 10 implants for each system were placed in the dental casts by using the manufacturer's recommended guided surgery protocols. After implant placement, postoperative CBCT images were made. The CBCT cast and implant images were superimposed onto the treatment-planning image. The implant positions, mesiodistal, labiopalatal, and vertical, as well as implant angulations were measured in the labiolingual and mesiodistal planes. The displacements from the planning in each dimension were recorded. ANOVA with the Tukey adjusted post hoc pairwise comparisons were used to examine the accuracy and precision of the 3 implant systems (α=.05). RESULTS The overall implant displacements were -0.02 ±0.13 mm mesially (M), 0.07 ±0.14 mm distally (D), 0.43 ±0.57 mm labially (L), and 1.26 ±0.80 mm palatally (P); 1.20 ±3.01 mm vertically in the mesiodistal dimension (VMD); 0.69 ±2.03 mm vertically in the labiopalatal dimension (VLP); 1.69 ±1.02 degrees in mesiodistal angulation (AMD); and 1.56 ±0.92 degrees in labiopalatal angulation (ALP). Statistically significant differences (ANOVA) were found in M (P=.026), P (P=.001), VMD (P=.009), AMD (P=.001), and ALP (P=.001). ZB showed the most displacements in the M and vertical dimensions and the least displacements in the P angulation (P<.05), suggesting statistically significant differences among the M, VMD, VLP, AMD, and ALP. NB had the most M variation. ZB had the least P deviation. NB had the fewest vertical dimension variations but the most angulation variations. CONCLUSIONS Dimensional and angulation displacements of guided implant systems by in-office 3D-printed fabrication were within clinically acceptable limits: <0.1 mm in M-D, 0.5 to 1 mm in L-P, and 1 to 2 degrees in angulation. However, the vertical displacement can be as much as 2 to 3 mm. Different implant guided surgery systems have strengths and weaknesses as revealed in the dimensional and angulation implant displacements.
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Affiliation(s)
- Matthew Yeung
- Former doctoral student, Department of General Practice, School of Dentistry, Virginia Commonwealth University, Richmond, Va
| | - Aous Abdulmajeed
- Assistant Professor and Director of Biomaterials, Department of General Practice, School of Dentistry, Virginia Commonwealth University, Richmond, Va
| | - Caroline K Carrico
- Assistant Professor, Department of Oral Health Promotion and Community Outreach, School of Dentistry, Virginia Commonwealth University, Richmond, Va; Assistant Professor, Department of Biostatistics, School of Medicine, Virginia Commonwealth University, Richmond, Va
| | - George R Deeb
- Professor, Department of Oral and Maxillofacial Surgery, School of Dentistry, Virginia Commonwealth University, Richmond, Va
| | - Sompop Bencharit
- Associate Professor and Director of Digital Dentistry Technologies, Department of General Practice and Department of Oral & Maxillofacial Surgery, School of Dentistry, Virginia Commonwealth University, Richmond, Va; Associate Professor, Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, Va.
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Bandyopadhyay A, Mitra I, Shivaram A, Dasgupta N, Bose S. Direct comparison of additively manufactured porous titanium and tantalum implants towards in vivo osseointegration. ADDITIVE MANUFACTURING 2019; 28:259-266. [PMID: 31406683 PMCID: PMC6690615 DOI: 10.1016/j.addma.2019.04.025] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Material properties of implants such as volume porosity and nanoscale surface modification have been shown to enhance cell-material interactions in vitro and osseointegration in vivo. Porous tantalum (Ta) and titanium (Ti) coatings are widely used for non-cemented implants, which are fabricated using different processing routes. In recent years, some of those implants are being manufactured using additive manufacturing. However, limited knowledge is available on direct comparison of additively manufactured porous Ta and Ti structures towards early stage osseointegration. In this study, we have fabricated porous Ta and Ti6Al4V (Ti64) implants using laser engineered net shaping (LENS™) with similar volume fraction porosity to compare the influence of surface characteristics and material chemistry on in vivo response using a rat distal femur model for 5 and 12 weeks. We have also assessed whether surface modification on Ti64 can elicit similar in vivo response as porous Ta in a rat distal femur model for 5 and 12 weeks. The harvested implants were histologically analyzed for osteoid surface per bone surface. Field emission scanning electron microscopy (FESEM) was done to assess the bone-implant interface. The results presented here indicate comparable performance of porous Ta and surface modified porous Ti64 implants towards early stage osseointegration at 5 weeks post implantation through seamless bone-material interlocking. However, a continued and extended efficacy of porous Ta is found in terms of higher osteoid formation at 12 weeks post-surgery.
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Affiliation(s)
- Amit Bandyopadhyay
- W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA, 99164, USA
| | - Indranath Mitra
- W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA, 99164, USA
| | - Anish Shivaram
- W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA, 99164, USA
| | - Nairanjana Dasgupta
- Department of Mathematics and Statistics, Washington State University, Pullman, WA, 99164, USA
| | - Susmita Bose
- W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA, 99164, USA
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Bencharit S, Morelli T, Barros S, Seagroves JT, Kim S, Yu N, Byrd K, Brenes C, Offenbacher S. Comparing Initial Wound Healing and Osteogenesis of Porous Tantalum Trabecular Metal and Titanium Alloy Materials. J ORAL IMPLANTOL 2019; 45:173-180. [PMID: 30663941 DOI: 10.1563/aaid-joi-d-17-00258] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Porous tantalum trabecular metal (PTTM) has long been used in orthopedics to enhance neovascularization, wound healing, and osteogenesis; recently, it has been incorporated into titanium alloy dental implants. However, little is known about the biological responses to PTTM in the human oral cavity. We have hypothesized that, compared with conventional titanium alloy, PTTM has a greater expression of genes specific to neovascularization, wound healing, and osteogenesis during the initial healing period. Twelve subjects requiring at least 4 implants in the mandible were enrolled. Four 3 × 5mm devices, including 2 titanium alloy tapered screws and 2 PTTM cylinders, were placed in the edentulous mandibular areas using a split-mouth design. One device in each group was trephined for analysis at 2 and 4 weeks after placement. RNA microarray analysis and ingenuity pathway analysis were used to analyze osteogenesis gene expression and relevant signaling pathways. Compared to titanium alloy, PTTM samples exhibited significantly higher expressions of genes specific to cell neovascularization, wound healing, and osteogenesis. Several genes-including bone morphogenic proteins, collagens, and growth factors-were upregulated in the PTTM group compared to the titanium alloy control. PTTM materials may enhance the initial healing of dental implants by modifying gene expression profiles.
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Affiliation(s)
- Sompop Bencharit
- 1 Departments of General Practice and Oral and Maxillofacial Surgery, School of Dentistry and Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, Va
| | - Thiago Morelli
- 2 Department of Periodontology, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Silvana Barros
- 2 Department of Periodontology, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Jackson T Seagroves
- 3 Department of Prosthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Steven Kim
- 4 Curriculum in Oral Biology, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Ning Yu
- 4 Curriculum in Oral Biology, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Kevin Byrd
- 4 Curriculum in Oral Biology, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Christian Brenes
- 5 Department of General Dentistry, Dental College of Georgia, Augusta University, Augusta, Ga
| | - Steven Offenbacher
- 2 Department of Periodontology, School of Dentistry, University of North Carolina, Chapel Hill, NC
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Suriyan N, Sarinnaphakorn L, Deeb GR, Bencharit S. Trephination-based, guided surgical implant placement: A clinical study. J Prosthet Dent 2018; 121:411-416. [PMID: 30503150 DOI: 10.1016/j.prosdent.2018.06.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 06/01/2018] [Accepted: 06/01/2018] [Indexed: 10/27/2022]
Abstract
STATEMENT OF PROBLEM Conventional guided implant surgery promises clinical success through implant placement accuracy; however, it requires multiple drills along with surgical sleeves and sleeve adapters for the horizontal and vertical control of osteotomy drills. This results in cumbersome surgery, problems with patients having limited mouth opening, and restriction to specific drill or implant manufacturers. A protocol for using trephination drills to simplify guided surgery and accommodate multiple implant systems is introduced. PURPOSE The purpose of this clinical study was to evaluate the accuracy of implant placement using this novel guided trephine drill protocol with and without a surgical sleeve. MATERIAL AND METHODS Intraoral scanning and preoperative cone beam computed tomography (CBCT) scans were used for implant treatment planning. Surgical guides were fabricated using stereolithography. Implant surgery was performed using the guided trephination protocol with and without a surgical sleeve. Postoperative CBCT scans were used to measure the implant placement deviations rather than the implant planning position. Surgical placement time and patient satisfaction were also documented. One-tailed t test and F-test (P=.01) were used to determine statistical significance. RESULTS Thirty-five implants in 17 participants were included in this study. With a surgical sleeve, implant positional deviations were 0.51 ±0.13 mm vertically, 0.32 ±0.10 mm facially, 0.11 ±0.11 mm lingually, and 0.38 ±0.13 mm mesially. Without a surgical sleeve, implant positional deviations were 0.58 ±0.27 mm vertically, 0.3 ±0.14 mm facially, 0.39 ±0.16 mm lingually, and 0.41 ±0.12 mm mesially. No statistically significant difference was found between the 2 protocols (P>.01), except that the sleeve group had greater vertical control precision (F-test, P=.006), reduced placement time, and the time variation was reduced (t test, P=.003; F-test, P<.001). CONCLUSIONS This trephination-based, guided implant surgery protocol produces accurate surgical guides that permit guided surgery in limited vertical access and with the same guided surgery protocol for multiple implant systems. Guided sleeves, although not always necessary, improve depth control and reduce surgical time in implant placement.
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Affiliation(s)
- Nawakamon Suriyan
- Clinical Instructor, Department of Dentistry, Prachatipat Hospital, Bangkok, Thailand
| | | | - George R Deeb
- Associate Professor and Director of Predoctoral and Postdoctoral Implantology, Department of Oral and Maxillofacial Surgery, School of Dentistry, Virginia Commonwealth University, Richmond, Va
| | - Sompop Bencharit
- Associate Professor and Director of Digital Dentistry Technologies, Department of General Practice and Department of Oral and Maxillofacial Surgery, School of Dentistry, Virginia Commonwealth University, Richmond, Va; Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, Va.
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12
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Edelmann AR, Patel D, Allen RK, Gibson CJ, Best AM, Bencharit S. Retrospective analysis of porous tantalum trabecular metal-enhanced titanium dental implants. J Prosthet Dent 2018; 121:404-410. [PMID: 30396711 DOI: 10.1016/j.prosdent.2018.04.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 04/26/2018] [Accepted: 04/26/2018] [Indexed: 11/16/2022]
Abstract
STATEMENT OF PROBLEM The design of porous tantalum trabecular metal-enhanced titanium (TM) dental implants promises improved osseointegration, especially when grafting materials such as demineralized bone matrix are used; however, studies are lacking. PURPOSE The purpose of this retrospective study was to compare TM implants with conventional titanium alloy (Ti) implants with and without demineralized bone matrix in terms of peri-implant bone remodeling in the first year after implant loading. MATERIAL AND METHODS A chart review was used for all patients receiving Tapered Screw-Vent Ti and TM implants. Implants were placed and restored by a single provider between 2011 and 2015. Peri-implant bone remodeling was compared by using a paired t test (α=.05). RESULTS A total of 82 patients received 205 implants, 44 TM and 161 Ti implants (control). No implants failed in the TM group (survival rate of 100%), and 3 implants in total, 1 immediate, failed in the Ti groups (survival rate of 98.1%). TM implants exhibited a 0.28-mm bone gain on average, whereas the control group demonstrated 0.20 mm of marginal bone loss after the first year of implant loading. Multivariate logistic regression analysis demonstrated that the odds of having bone loss was 64% less (odds ratio: 0.36; 95% confidence interval: 0.14-0.94) in the TM group than in the Ti group after controlling for bone grafting, implant location, immediate placement, bone type, and pretreatment bone level. CONCLUSIONS TM implants exhibited less peri-implant bone loss than the control Ti implants.
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Affiliation(s)
- Alexander R Edelmann
- Resident, Department of Orthodontics, School of Dentistry, University of Texas Health Science Center, Houston, Texas
| | - Devang Patel
- Former doctoral student, Department of Prosthodontics, School of Dentistry, Virginia Commonwealth University, Richmond, Va
| | - Riley K Allen
- Research Assistant, Department of Prosthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Chad J Gibson
- Undergraduate Research Assistant, Department of Prosthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Al M Best
- Professor and Director of Faculty Research Development, Department of Periodontics, School of Dentistry, Virginia Commonwealth University, Richmond, Va
| | - Sompop Bencharit
- Associate Professor and Director of Digital Dentistry Technologies, Department of General Practice and Department of Oral and Maxillofacial Surgery, School of Dentistry; and Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, Va.
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13
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Bencharit S, Staffen A, Yeung M, Whitley D, Laskin DM, Deeb GR. In Vivo Tooth-Supported Implant Surgical Guides Fabricated With Desktop Stereolithographic Printers: Fully Guided Surgery Is More Accurate Than Partially Guided Surgery. J Oral Maxillofac Surg 2018; 76:1431-1439. [DOI: 10.1016/j.joms.2018.02.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 02/13/2018] [Accepted: 02/13/2018] [Indexed: 02/08/2023]
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14
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Deeb G, Koerich L, Whitley D, Bencharit S. Computer-guided implant removal: A clinical report. J Prosthet Dent 2018; 120:796-800. [PMID: 29807745 DOI: 10.1016/j.prosdent.2017.10.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 10/20/2017] [Accepted: 10/21/2017] [Indexed: 12/17/2022]
Abstract
Occasionally, osseointegrated dental implants must be removed because of complications such as malpositioning or screw fracture. This is most often accomplished with a surgical handpiece and trephine. However, a flap is often required to access and visualize the implants. This paper presents a treatment in which computer planning and a 3-dimensional-printed, custom fabricated, surgical guide was used to assist in implant removal. This technique simplified the procedure, allowed conservative removal of peri-implant bone, and permitted subsequent immediate implant replacement.
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Affiliation(s)
- George Deeb
- Associate Professor, Department of Oral and Maxillofacial Surgery, School of Dentistry, Virginia Commonwealth University, Richmond, Va
| | - Leonard Koerich
- Former predoctoral student, School of Dentistry, Virginia Commonwealth University, Richmond, Va
| | | | - Sompop Bencharit
- Associate Professor, Department of General Practice, School of Dentistry, and Director of Digital Dentistry Technologies, Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, Va.
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15
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Immediate Loading of Tantalum-Based Implants in Fresh Extraction Sockets in Patient With Sjogren Syndrome. IMPLANT DENT 2017; 26:634-638. [DOI: 10.1097/id.0000000000000594] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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Whitley D, Eidson RS, Rudek I, Bencharit S. In-office fabrication of dental implant surgical guides using desktop stereolithographic printing and implant treatment planning software: A clinical report. J Prosthet Dent 2017; 118:256-263. [PMID: 28222882 DOI: 10.1016/j.prosdent.2016.10.017] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 10/13/2016] [Accepted: 10/13/2016] [Indexed: 12/27/2022]
Abstract
Guided surgery is accepted as the most accurate way to place an implant and predictably relate the implant to its definitive prosthesis, although few clinicians use it. However, recent developments in high-quality desktop 3-dimensional stereolithographic printers have led to the in-office fabrication of stereolithographic surgical guides at reduced cost. This clinical report demonstrates a protocol for using a cost-effective, in-office rapid prototyping technique to fabricate a surgical guide for dental implant placement.
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Affiliation(s)
| | - R Scott Eidson
- Clinical Associate Professor, Department of Operative Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, N.C
| | - Ivan Rudek
- Research Assistant Professor, General and Oral Health Center, Department of Periodontics, University of North Carolina at Chapel Hill, Chapel Hill, N.C
| | - Sompop Bencharit
- Associate Professor and Director, Digital Dentistry Technologies, Department of General Practice and Department of Oral and Maxillofacial Surgery, School of Dentistry, and Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, Va.
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17
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Kang C, Wei L, Song B, Chen L, Liu J, Deng B, Pan X, Shao L. Involvement of autophagy in tantalum nanoparticle-induced osteoblast proliferation. Int J Nanomedicine 2017; 12:4323-4333. [PMID: 28652735 PMCID: PMC5473603 DOI: 10.2147/ijn.s136281] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Porous tantalum (Ta) implants are highly corrosion resistant and biocompatible, and they possess significantly better initial stability than that of conventional titanium (Ti) implants. During loading wear, Ta nanoparticles (Ta-NPs) that were deposited on the surface of a porous Ta implant are inevitably released and come into direct contact with peri-implant osteoblasts. The wear debris may influence cell behavior and implant stabilization. However, the interaction of Ta-NPs with osteoblasts has not been clearly investigated. This study aimed to investigate the effect of Ta-NPs on cell proliferation and their underlying mechanism. The Cell Counting Kit-8 (CCK-8) assay was used to measure the cell viability of MC3T3-E1 mouse osteoblasts and showed that Ta-NP treatment could increase cell viability. Then, confocal microscopy, Western blotting, and transmission electron microscopy were used to confirm the autophagy induced by Ta-NPs, and evidence of autophagy induction was observed as positive LC3 puncta, high-LC3-II expression, and autophagic vesicle ultrastructures. The CCK-8 assay revealed that the cell viability was further increased and decreased by the application of an autophagy inducer and inhibitor, respectively. In addition, pre-treatment with autophagy inhibitor 3-methyladenine (3-MA) inhibited the Ta-NP-induced autophagy. These results indicate that the Ta-NPs can promote cell proliferation, that an autophagy inducer can further strengthen this effect and that an autophagy inhibitor can weaken this effect. In conclusion, autophagy was involved in Ta-NP-induced cell proliferation and had a promoting effect.
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Affiliation(s)
- Chengrong Kang
- Department of Stomatology, Nanfang Hospital, Southern Medical University
- Department of Stomatology, The First Affiliated Hospital of Guangdong Pharmaceutical University
| | - Limin Wei
- Department of Stomatology, Nanfang Hospital, Southern Medical University
| | - Bin Song
- Department of Stomatology, Nanfang Hospital, Southern Medical University
| | - Liangjiao Chen
- Department of Orthodontics, Key Laboratory of Oral Medicine, Guangzhou Institute of Oral Disease, Stomatology Hospital of Guangzhou Medical University, Guangzhou
| | - Jia Liu
- Department of Stomatology, Nanfang Hospital, Southern Medical University
| | - Bin Deng
- Department of Stomatology, The General Hospital of People’s Liberation Army, Beijing, China
| | - Xuan Pan
- Department of Stomatology, The First Affiliated Hospital of Guangdong Pharmaceutical University
- Xuan Pan, Department of Stomatology, The First Affiliated Hospital of Guangdong Pharmaceutical University, 19 Nonglinxialu, Guangzhou 510080, China, Tel/fax +86 20 6132 5457, Email
| | - Longquan Shao
- Department of Stomatology, Nanfang Hospital, Southern Medical University
- Correspondence: Longquan Shao, Department of Stomatology, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Road, Guangzhou 510515, China, Tel +86 20 6278 7153, Fax +86 20 6164 1101, Email
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18
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Fu Q, Bellare A, Cui Y, Cheng B, Xu S, Kong L. The Effect of Hierarchical Micro/Nanotextured Titanium Implants on Osseointegration Immediately After Tooth Extraction in Beagle Dogs. Clin Implant Dent Relat Res 2016; 19:486-495. [PMID: 28008710 DOI: 10.1111/cid.12464] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Owing to simplify the operation and shorten the overall duration of treatment, immediate implantation earned much satisfactory from patients and dentists. The results of immediate implantation determined by osseointegration, we fabricated a micro/nanotextured titanium implants to improve osseointegration immediately after tooth extraction. PURPOSE The aim of this study was to investigate the effect of hierarchical micro/nanotextured titanium implant on osseointegration immediately after tooth extraction. MATERIAL AND METHODS The micro/nanotextured titanium implants were fabricated by etching with 0.5 wt% hydrofluoric (HF) acid followed by anodization in HF electrolytes. Implants with a machined surface as well as implants a microtextured surface prepared by 0.5 wt% HF etching served as control groups. The machined, microtextured, and micro/nanotextured implants were inserted into fresh sockets immediately after tooth extraction in beagle dogs. Twelve weeks after implantation, the animals were sacrificed for micro-CT scanning, histological analysis and biomechanical test. RESULTS The micro-CT imaging revealed that the bone volume/total volume (BV/TV) and trabecular thickness (Tb.Th) in the micro/nanotextured group was significantly higher than that in the machined group and microtextured group, and the trabecular separation (Tb.Sp) in the micro/nanotextured group was significantly lower than that in the other groups. For the histological analysis, the bone-to-implant contact in the machined, micro and micro/nanotextured groups were 47.13 ± 6.2%, 54.29 ± 4.18%, and 63.38 ± 7.63%, respectively, and the differences significant. The maximum pull-out force in the machined, micro, and micro/nanotextured groups were 216.58 ± 38.71 N, 259.42 ± 28.93 N, and 284.73 ± 47.09 N, respectively. CONCLUSIONS The results indicated that implants with a hierarchical micro/nanotextured can promote osseointegration immediately after tooth extraction.
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Affiliation(s)
- Qian Fu
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Oral and Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China
| | - Anuj Bellare
- Department of Orthopedic Surgery, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St, Boston, MA, USA
| | - Yajun Cui
- Orthopedic Research Laboratories, Department of Orthopedic Surgery, Children's Hospital, Boston, Massachusetts, USA
| | - Bingkun Cheng
- Department of Oral and Maxillofacial Surgery, School of Stomatology, The Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China
| | - Shanshan Xu
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Oral and Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China
| | - Liang Kong
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Oral and Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China
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19
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El Chaar E, Castaño A. A Retrospective Survival Study of Trabecular Tantalum Implants Immediately Placed in Posterior Extraction Sockets Using a Flapless Technique. J ORAL IMPLANTOL 2016; 43:114-124. [PMID: 27967312 DOI: 10.1563/aaid-joi-d-16-00071] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A retrospective review of patient records was conducted in a single private practice to evaluate the efficacy of immediately placing a novel implant design in posterior jaw locations using a flapless technique. Forty-two patients (22 males, 20 females) with a mean (SD) age of 60.2 (7.6) years (range = 31-68) presented with 1-2 nonrestorable molar (maxillary = 14; mandibular = 8) or premolar (maxillary = 20; mandibular = 1) teeth compromised by periodontal disease, endodontic failure, root resorption, root fracture, or severe caries. Most patients (78.6%) had moderate (66.7%) or severe (11.9%) periodontitis. Other comorbidities included smoking (14.3%) and controlled diabetes mellitus (11.9%). After atraumatic extraction, teeth were immediately replaced with a total of 44 trabecular tantalum implants (Trabecular Metal Implants, Zimmer Biomet Dental) (diameter = 3.7-4.7 mm; length = 10-13 mm). Sites requiring augmentation were treated with 3 types of small-particle (250-1000 μm), mineralized, solvent-dehydrated, allografts (Puros) based on location: cortical for crestal sinus grafts, cancellous for peri-implant voids in thick tissue biotypes, or cortical-cancellous (70:30) mix for peri-implant voids in thin tissue biotypes. Cortical particulate was used when slower resorption would help maintain graft volume for esthetics or implant support. Grafts were covered with resorbable bovine pericardium membranes (CopiOs, Zimmer Biomet). Cumulative implant survival and success rates were 97.7%, respectively, with a mean (±SD) follow-up time of 25.0 ± 12.1 months (range = 4-48). One asymptomatic implant failed to osseointegrate. Within the limitations of this study, implants achieved outcomes comparable to conventionally placed and restored single-tooth implants in anterior jaw locations.
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Affiliation(s)
- Edgard El Chaar
- 1 Private practice, New York, NY.,2 College of Dentistry, New York University, NY
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20
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Bencharit S, Allen RK, Whitley D. Utilization of Demineralized Bone Matrix to Restore Missing Buccal Bone During Single Implant Placement: Clinical Report. J ORAL IMPLANTOL 2016; 42:490-497. [DOI: 10.1563/aaid-joi-d-16-00054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Sompop Bencharit
- Department of Prosthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Riley K. Allen
- Department of Prosthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Daniel Whitley
- Department of Prosthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC
- Department of General Practice, School of Dentistry; and Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, Va
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21
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Edelmann AR, Hosseini B, Byrd WC, Preisser JS, Tyndall DA, Nguyen T, Bencharit S. Exploring Effectiveness of Computer-Aided Planning in Implant Positioning for a Single Immediate Implant Placement. J ORAL IMPLANTOL 2016; 42:233-9. [DOI: 10.1563/aaid-joi-d-15-00056] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The value of computer-aided implant planning using cone-beam computerized tomography (CBCT) for single immediate implants was explored. Eighteen patients requiring extraction of a tooth followed by a single immediate implant were enrolled. Small volume preoperative CBCT scans were used to plan the position of the implant. A taper screwed–type implant was immediately placed into a fresh socket using only the final 1 or 2 drills for osteotomy. Postoperative CBCTs were used for the analysis of actual implant placement positioning. Measurements of the planned and the actual implant position were made with respect to their position relative to the adjacent teeth. Mesio-distal displacements and the facial-lingual deviation of the implant from the planned position were determined. Changes in the angulation of the planned and actual implant position in relation to the clinical crown were also measured. To statistically summarize the results, box plots and 95% CIs for means of paired differences were used. The analysis showed no statistical difference between the planned position and final implant placement position in any measurement. The CBCT scans coupled with the computer-aided implant planning program along with a final 1-to-2 drill protocol may improve the accuracy of single immediate implant placement for taper screwed–type implants.
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Affiliation(s)
| | - Bashir Hosseini
- Department of Endodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Warren C. Byrd
- School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - John S. Preisser
- Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC
| | - Donald A. Tyndall
- Department of Diagnostic Sciences, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Tung Nguyen
- Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Sompop Bencharit
- Department of Prosthodontics, School of Dentistry; and Department of Pharmacology, School of Medicine, University of North Carolina, Chapel Hill, NC
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