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Fan DY, Zhai HY, Zhao Y, Qiao X, Zhu DC, Liu HJ, Liu C. The role of cannabinoid receptor 2 in bone remodeling during orthodontic tooth movement. BMC Oral Health 2024; 24:23. [PMID: 38178129 PMCID: PMC10768142 DOI: 10.1186/s12903-023-03810-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 12/19/2023] [Indexed: 01/06/2024] Open
Abstract
BACKGROUND The purpose of this study is to explore the effects of CB2 on bone regulation during orthodontic tooth movement. METHODS Thirty male mice were allocated into 2 groups (n = 15 in each group): wild type (WT) group and CB2 knockout (CB2-/-) group. Orthodontic tooth movement (OTM) was induced by applying a nickel-titanium coil spring between the maxillary first molar and the central incisors. There are three subgroups within the WT groups (0, 7 and 14 days) and the CB2-/- groups (0, 7 and 14 days). 0-day groups without force application. Tooth displacement, alveolar bone mass and alveolar bone volume were assessed by micro-CT on 0, 7 and 14 days, and the number of osteoclasts was quantified by tartrate-resistant acid phosphatase (TRAP) staining. Moreover, the expression levels of RANKL and OPG in the compression area were measured histomorphometrically. RESULTS The WT group exhibited the typical pattern of OTM, characterized by narrowed periodontal space and bone resorption on the compression area. In contrast, the accelerated tooth displacement, increased osteoclast number (P < 0.0001) and bone resorption on the compression area in CB2-/- group. Additionally, the expression of RANKL was significantly upregulated, while OPG showed low levels in the compression area of the CB2 - / - group (P < 0.0001). CONCLUSIONS CB2 modulated OTM and bone remodeling through regulating osteoclast activity and RANKL/OPG balance.
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Affiliation(s)
- Deng-Ying Fan
- Department of Orthodontics, School and Hospital of Stomatology, Hebei Medical University & Hebei Key Laboratory of Stomatology & Hebei Clinical Research Center for Oral Diseases, East 383 Zhongshan Road, Shijiazhuang, Hebei Province, 050017, China
| | - Hao-Yan Zhai
- Department of Orthodontics, School and Hospital of Stomatology, Hebei Medical University & Hebei Key Laboratory of Stomatology & Hebei Clinical Research Center for Oral Diseases, East 383 Zhongshan Road, Shijiazhuang, Hebei Province, 050017, China
| | - Yuan Zhao
- Department of Orthodontics, School and Hospital of Stomatology, Hebei Medical University & Hebei Key Laboratory of Stomatology & Hebei Clinical Research Center for Oral Diseases, East 383 Zhongshan Road, Shijiazhuang, Hebei Province, 050017, China
| | - Xing Qiao
- Department of Orthodontics, School and Hospital of Stomatology, Hebei Medical University & Hebei Key Laboratory of Stomatology & Hebei Clinical Research Center for Oral Diseases, East 383 Zhongshan Road, Shijiazhuang, Hebei Province, 050017, China
| | - De-Chao Zhu
- Department of Orthodontics, School and Hospital of Stomatology, Hebei Medical University & Hebei Key Laboratory of Stomatology & Hebei Clinical Research Center for Oral Diseases, East 383 Zhongshan Road, Shijiazhuang, Hebei Province, 050017, China
| | - Hui-Juan Liu
- The Key Laboratory of Stomatology, School and Hospital of Stomatology, Hebei Medical University & Hebei Key Laboratory of Stomatology, Clinical Research Center for Oral Diseases, East 383 Zhongshan Road, Shijiazhuang, Hebei Province, 050017, China.
| | - Chunyan Liu
- Department of Orthodontics, School and Hospital of Stomatology, Hebei Medical University & Hebei Key Laboratory of Stomatology & Hebei Clinical Research Center for Oral Diseases, East 383 Zhongshan Road, Shijiazhuang, Hebei Province, 050017, China.
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Wang M, Wang J, Jin X, Liu D, Bian H, Zhao Y, Li Y. Impact of occlusal contact pattern on dental stability and oromandibular system after orthodontic tooth movement in rats. Sci Rep 2023; 13:22276. [PMID: 38097596 PMCID: PMC10721791 DOI: 10.1038/s41598-023-46668-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 11/03/2023] [Indexed: 12/17/2023] Open
Abstract
How to ensure dental stability in new positions and reduce the likelihood of relapse is a major clinical concern in the orthodontic field. Occlusal contacts between arches may affect the transmission of masticatory forces, thereby influencing the biological response of the periodontal and the oromandibular system. Occlusion factors that may influence the stability after orthodontic tooth movement (OTM) remain largely unknown. Hence, this research was conducted in order to investigate the influence of different occlusal contact patterns on tooth stability and oromandibular system including the masseter muscle and the temporomandibular joint following OTM. By modifying the occlusal surfaces, in vivo animal study models with distinct occlusal patterns corresponding to clinical circumstances were established. The relapse distance of teeth and the level of inflammatory factors in the gingival cervical fluid were analyzed. We also closely observed the histological remodeling of periodontal tissue, masseter tissue, and joint tissue after one week of relapse. Moreover, genes expression in the alveolar bone was analyzed to illustrate the potential biological mechanisms of relapse under the influence of different occlusal contact patterns following OTM. Different occlusal contact patterns after OTM in rats were established. The intercuspation contact between cusp and fossa group exhibited the lowest level of relapse movement, inflammatory factors and osteoclast activity (P < 0.05). On the other hand, groups with interferences or inadequate contacts exhibited more relapse movement, and tend to promote inflammation of periodontal tissue and activate bone resorption (P < 0.05). Adequate occlusal contacts without interference may enhance tooth stability and reduce the likelihood of relapse. After active orthodontic treatment, necessary occlusal adjustment should be made to achieve the desired intercuspation contact relationship and ensure adequate contact between the arches. The elimination of occlusal interferences is crucial to achieving optimal stability and promoting overall healthy condition of the oromandibular system.
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Affiliation(s)
- Menglin Wang
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, No. 51 Fucheng Road, Haidian District, Beijing, 100048, China
- Department of Stomatology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, 100043, China
| | - Jing Wang
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, No. 51 Fucheng Road, Haidian District, Beijing, 100048, China
| | - Xiang Jin
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, No. 51 Fucheng Road, Haidian District, Beijing, 100048, China
| | - Dedi Liu
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, No. 51 Fucheng Road, Haidian District, Beijing, 100048, China
| | - Huan Bian
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, No. 51 Fucheng Road, Haidian District, Beijing, 100048, China.
| | - Yantao Zhao
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, No. 51 Fucheng Road, Haidian District, Beijing, 100048, China.
- Department of Orthopedics, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, 100048, China.
- Beijing Engineering Research Center of Orthopedics Implants, Beijing, 100048, China.
- State Key Laboratory of Military Stomatology, Xi'an, 710032, China.
| | - Yanfeng Li
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, No. 51 Fucheng Road, Haidian District, Beijing, 100048, China.
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Yan M, Zhang Y, Niu W, Liu K, Xue L, Zhou K. Reactive oxygen species-mediated endoplasmic reticulum stress contributes to osteocyte death induced by orthodontic compressive force. Microsc Res Tech 2023; 86:1529-1541. [PMID: 37382312 DOI: 10.1002/jemt.24382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 05/22/2023] [Accepted: 06/18/2023] [Indexed: 06/30/2023]
Abstract
During orthodontic tooth movement (OTM), osteocytes, the most mechanosensitive cells in alveolar bone, suffer the heavy orthodontic force and initiate alveolar bone resorption on the compression side. However, the inherent mechanisms of compressive force-induced osteocyte death are not fully understood. In this study, we established an OTM model on Sprague-Dawley rats by inserting coil springs to investigate osteocyte damage on the compression side of alveolar bone. We then applied compressive force on the MLO-Y4 osteocyte-like cell line in vitro to explore whether the reactive oxygen species (ROS)-mediated endoplasmic reticulum stress (ERS) pathway is involved in compressive force-induced osteocyte death. We found that the orthodontic force caused apparent alveolar bone loss, osteocyte death, and elevated serum sclerostin and receptor activator of NF-κB ligand (RANKL) levels in rats. In vitro, compressive force inhibited cell viability but increased the LDH leakage and loss of mitochondrial membrane potential in MLO-Y4 cells. Simultaneously, it activated protein kinase RNA-like endoplasmic reticulum kinase (PERK), eukaryotic translation initiation factor 2 (eIF2α), and their downstream pro-apoptotic ERS signaling proteins and caused significant osteocyte apoptosis, which can be blocked by ERS inhibitor salubrinal. Moreover, the compressive force elevated intracellular ROS levels, while the ROS scavenger N-acetyl-L-cysteine (NAC) alleviated ERS and apoptosis in loaded osteocytes. These results suggest that the orthodontic compressive force induced osteocyte apoptosis via the ROS-mediated ERS pathway. This study first proposes the ERS pathway as a new potential pathway for regulating the rate of OTM based on osteocyte death. RESEARCH HIGHLIGHTS: The orthodontic force increases osteocyte death in rat alveolar bone. The compressive force causes osteocyte apoptosis by the endoplasmic reticulum stress (ERS) pathway in vitro. The ROS scavenger NAC blocked compressive force-induced ERS and osteocyte apoptosis.
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Affiliation(s)
- Ming Yan
- School of Automation, Hangzhou Dianzi University, Hangzhou, People's Republic of China
| | - Yun Zhang
- College of Medicine, Shaoxing University, Shaoxing, People's Republic of China
| | - Wanting Niu
- Department of STEM, Regis College, Weston, Massachusetts, USA
| | - Kezhou Liu
- School of Automation, Hangzhou Dianzi University, Hangzhou, People's Republic of China
| | - Lingyun Xue
- School of Automation, Hangzhou Dianzi University, Hangzhou, People's Republic of China
| | - Kexin Zhou
- West China School of Medicine, Sichuan University, Chengdu, People's Republic of China
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Wang M, Fan J, Wang A, Jin X, Zhang Z, Hu X, Liu L, Zhao Y, Li Y. Effect of local application of bone morphogenetic protein -2 on experimental tooth movement and biological remodeling in rats. Front Physiol 2023; 14:1111857. [PMID: 37143931 PMCID: PMC10151543 DOI: 10.3389/fphys.2023.1111857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 03/27/2023] [Indexed: 05/06/2023] Open
Abstract
Background: This study attempts to detect the potential effects of local bone morphogenetic protein -2 (BMP-2) on orthodontic tooth movement and periodontal tissue remodeling. Methods: Forty adult SD rats were randomly divided into four groups: blank control group, unilateral injection of BMP-2 on the pressure side or tension side of orthodontic teeth and bilateral injection of BMP-2. Their maxillary first molar was moved by a 30 g constant force closed coil spring. 60 μL of BMP-2 with a concentration of 0.5 μg/mL was injected into each part at a time. In addition, three rats were selected as healthy control rats without any intervention. Fluorescent labeled BMP-2 was used to observe the distribution of exogenous BMP-2 in tissues. Micro-CT was used to measure the microscopic parameters of tooth displacement, trabecular bone and root absorption volume. Three different histological methods were used to observe the changes of tissue remodeling, and then the number of osteoclasts and the content of collagen fibers were calculated. Results: Compared with the blank control group, BMP-2 injection reduced the movement distance and increased the collagen fiber content and bone mass (p < 0.01). There was no significant difference in tooth movement distance, BV/TV ratio and BMD between injection sites in unilateral injection group (p > 0.05). In the case of bilateral injection of BMP-2, the osteogenesis is enhanced. Unilateral injection of BMP-2 did not promote root resorption, but double injection showed root resorption (p < 0.01). Conclusion: Our study does show that the osteogenesis of BMP-2 is dose-dependent rather than site-dependent when a certain amount of BMP-2 is applied around orthodontic teeth. Local application of BMP-2 around orthodontic teeth in an appropriate way can enhance bone mass and tooth anchorage without increasing the risk of root absorption volume. However, high levels of BMP-2 may cause aggressive root resorption. These findings are of great significance, that is, BMP-2 is an effective target for regulating orthodontic tooth movement.
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Affiliation(s)
- Menglin Wang
- Medical School of Chinese PLA, Beijing, China
- Department of Stomatology, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Jiadong Fan
- Department of Stomatology, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Aoao Wang
- Senior Department of Orthopedics, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Xiang Jin
- Department of Stomatology, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Zhenbao Zhang
- Department of Stomatology, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Xiantong Hu
- Senior Department of Orthopedics, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Le Liu
- Department of Stomatology, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
- *Correspondence: Le Liu, ; Yantao Zhao, ; Yanfeng Li,
| | - Yantao Zhao
- Department of Stomatology, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
- Senior Department of Orthopedics, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
- Beijing Engineering Research Center of Orthopedics Implants, Beijing, China
- State Key Laboratory of Military Stomatology, Xi’an, China
- *Correspondence: Le Liu, ; Yantao Zhao, ; Yanfeng Li,
| | - Yanfeng Li
- Medical School of Chinese PLA, Beijing, China
- Department of Stomatology, The Fourth Medical Centre, Chinese PLA General Hospital, Beijing, China
- *Correspondence: Le Liu, ; Yantao Zhao, ; Yanfeng Li,
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Dynamic changes in tooth displacement and bone morphometry induced by orthodontic force. Sci Rep 2022; 12:13672. [PMID: 35953700 PMCID: PMC9372182 DOI: 10.1038/s41598-022-17412-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 07/25/2022] [Indexed: 11/08/2022] Open
Abstract
This study used a novel 3D analysis to longitudinally evaluate orthodontic tooth movement (OTM) and bone morphometry. Twelve-week-old male Wistar rats were subjected to OTM by applying a constant orthodontic force (OF) of 25cN between one of the upper first molars and a mini-screw. In vivo micro-CTs were taken before and after 10, 17, 24 and 31 days of force application, and superimposed by a novel and rigid voxel-based registration method. Then the tooth and alveolar bone segment at different time points became comparable in the same coordinate system, which facilitated the analysis of their dynamic changes in 3D. By comparison between time points and between OF and no OF sides, this study showed that the OTM rate was not constant through time, but conformed to a ‘V’ shape changing pattern. Besides, OF induced displacement of both loaded and unloaded teeth, and the latter mirrored the former in a delayed manner. In addition, bone morphometric changes synchronized with OTM rate changes, implying that a higher OTM rate was concomitant with more alveolar bone loss. The pressure and tension areas might not be in two opposite sides, but actually adjacent and connected. These findings might provide instructive evidence for both clinical, translational and basic research in orthodontics.
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Satomi K, Nishimura K, Igarashi K. Semaphorin 3A protects against alveolar bone loss during orthodontic tooth movement in mice with periodontitis. J Periodontal Res 2022; 57:991-1002. [PMID: 35899793 DOI: 10.1111/jre.13038] [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: 11/26/2021] [Revised: 07/04/2022] [Accepted: 07/12/2022] [Indexed: 10/16/2022]
Abstract
OBJECTIVE This study investigated the effect of local semaphorin 3A (Sema3A) administration on alveolar bone loss during OTM in a mouse model of periodontitis. BACKGROUND Orthodontic tooth movement (OTM) for patients with periodontal disease is known to increase the risk of exacerbating alveolar bone loss due to inflammation of the periodontal tissue. However, its mechanism of action and prevention remains unclear. METHODS Mice (male 7-8 weeks old, C57BL/6J, n = 12) were divided into six groups: untreated group (control), without OTM and recovered from induced periodontitis (RP), with OTM and administered PBS or Sema3A to the gingiva after induced periodontitis (VehPO, SemaPO), with OTM and administered PBS or Sema3A to the gingiva without periodontitis induction (VehNO, SemaNO). Samples were collected on 14 days, and bone loss, histological analysis, cytokine production level, and tooth movement were assessed. Cultured human periodontal ligament (hPDL) cells were stimulated with lipopolysaccharide (LPS) and compressive force (CF), and mRNA expression levels of Sema3A and its receptors were analyzed. RESULTS The bone loss was significantly lower in the SemaPO group than in the VehPO group. The number of TRAP-positive cells in the SemaPO group was significantly lower than that in the VehPO group and was at the same level as that in the control group. The receptor activator of nuclear factor (NF)-kB-ligand/osteoprotegerin (RANKL/OPG) ratio and the levels of proinflammatory cytokines, including interleukin (IL)-1β, IL-6, IL-17, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ, in the gingival tissues were significantly lower in the SemaPO group than in the VehPO group. Additionally, Sema3A mRNA expression in hPDL cells was significantly decreased by co-stimulation with LPS and CF compared with that in the control group. Finally, the distance moved (dist.) and the mesial tipping angle (θ) was significantly smaller in the SemaPO group than in the VehPO group and was not significantly different from that of VehNO. CONCLUSION Pathological alveolar bone loss exacerbated by OTM in periodontitis might be prevented by local administration of Sema3A without inhibiting OTM.
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Affiliation(s)
- Kazuki Satomi
- Division of Craniofacial Anomalies, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Kazuaki Nishimura
- Division of Craniofacial Anomalies, Tohoku University Graduate School of Dentistry, Sendai, Japan.,Department of Orthodontics and Speech Therapy for Craniofacial Anomalies, Tohoku University Hospital, Sendai, Japan
| | - Kaoru Igarashi
- Division of Craniofacial Anomalies, Tohoku University Graduate School of Dentistry, Sendai, Japan.,Department of Orthodontics and Speech Therapy for Craniofacial Anomalies, Tohoku University Hospital, Sendai, Japan
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Marcantonio CC, Lopes MES, Mofatto LS, Salmon CR, Deschner J, Nociti-Junior FH, Cirelli JA, Nogueira AVB. Obesity affects the proteome profile of periodontal ligament submitted to mechanical forces induced by orthodontic tooth movement in rats. J Proteomics 2022; 263:104616. [PMID: 35595054 DOI: 10.1016/j.jprot.2022.104616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 05/05/2022] [Accepted: 05/09/2022] [Indexed: 12/20/2022]
Abstract
The prevalence of obesity has increased significantly worldwide. Therefore, this study aimed to evaluate the influence of obesity on the proteomic profile of periodontal ligament (PDL) tissues of rat first maxillary molars (1 M) submitted to orthodontic tooth movement (OTM). Ten Holtzman rats were distributed into two groups (n = 5): the M group (OTM), and the OM group (obesity induction plus OTM). Obesity was induced by a high-fat diet for the entire experimental periods After that period, the animals were euthanized and the hemimaxillae removed and processed for laser capture microdissection of the PDL tissues of the 1 M. Peptide extracts were obtained and analyzed by LC-MS/MS. Data are available via ProteomeXchange with identifier PXD033647. Out of the 109 proteins with differential abundance, 49 were identified in the OM group, including Vinculin, Cathepsin D, and Osteopontin, which were selected for in situ localization by immunohistochemistry analysis (IHC). Overall, Gene Ontology (GO) analysis indicated that enriched proteins were related to the GO component cellular category. IHC validated the trends for selected proteins. Our study highlights the differences in the PDL proteome profiling of healthy and obese subjects undergoing OTM. These findings may provide valuable information needed to better understand the mechanisms involved in tissue remodeling in obese patients submitted to orthodontic treatment. SIGNIFICANCE: The prevalence of obesity is increasing worldwide. Emerging findings in the field of dentistry suggest that obesity influences the tissues around the teeth, especially those in the periodontal ligament. Therefore, evaluation of the effect of obesity on periodontal tissues remodeling during orthodontic tooth movement is a relevant research topic. To our knowledge, this is the first study to evaluate proteomic changes in periodontal ligament tissue in response to the association between orthodontic tooth movement and obesity. Our study identified a novel protein profile associated with obesity by using laser microdissection and proteomic analysis, providing new information to increase understanding of the mechanisms involved in obese patients undergoing orthodontic treatment which can lead to a more personalized orthodontic treatment approach.
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Affiliation(s)
- Camila Chierici Marcantonio
- Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Sao Paulo State University - UNESP, Araraquara, São Paulo, Brazil.
| | - Maria Eduarda Scordamaia Lopes
- Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Sao Paulo State University - UNESP, Araraquara, São Paulo, Brazil.
| | - Luciana Souto Mofatto
- Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
| | - Cristiane Ribeiro Salmon
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, São Paulo, Brazil
| | - James Deschner
- Department of Periodontology and Operative Dentistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany.
| | - Francisco Humberto Nociti-Junior
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, São Paulo, Brazil; São Leopoldo Mandic Research Center, Campinas, São Paulo, Brazil.
| | - Joni Augusto Cirelli
- Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Sao Paulo State University - UNESP, Araraquara, São Paulo, Brazil.
| | - Andressa Vilas Boas Nogueira
- Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Sao Paulo State University - UNESP, Araraquara, São Paulo, Brazil; Department of Periodontology and Operative Dentistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany.
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