File Download
  Links for fulltext
     (May Require Subscription)
Supplementary

postgraduate thesis: Role of periodontal diseases in bisphosphonate-related osteonecrosis of the jaws

TitleRole of periodontal diseases in bisphosphonate-related osteonecrosis of the jaws
Authors
Issue Date2014
PublisherThe University of Hong Kong (Pokfulam, Hong Kong)
Citation
Li, C. [李春蕾]. (2014). Role of periodontal diseases in bisphosphonate-related osteonecrosis of the jaws. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5387954
AbstractDespite the acknowledged benefit of bisphosphonates (BPs) in controlling bone disorders characterized by over-activity of osteoclasts-mediated bone resorption, a severe complication known as BPs-related osteonecrosis of the jaws (BRONJ) has been a major concern for both patients and clinicians. The study aimed to: 1) Investigate if ovariectomy(OVX) in rats could simulate intracortical remodeling process of the human skeleton; 2)Study the effect of zoledronic acid (ZA)on bone remodeling in the OVX rat model;3) Assess the role of periodontal diseases induced by ligature placement in the development of BRONJ on the OVX rat model;4) Evaluate the impact of Actinomyces naeslundii (An)and Fusobacterium nucleraide(Fn)inoculation on the progression of BRONJ in OVX rat model with periodontal diseases. In the preliminary study, Sprague-Dawly (SD) female rats received OVX surgery or sham operation and were treated with ZA or saline vehicle. After 12 weeks, rats were sacrificed and the mandibles were subjected to micro-computed tomography (micro-CT) and histomorphometric examinations. Intracortical remodeling in the mandible was significantlystimulated by OVX surgery, especially in the alveolar region (6-time higher than control), and remarkably inhibited by ZA treatment. The study for the first time demonstrated that OVX could stimulate intracortical remodeling in jawbones of rats. It provides hard evidence that ovariectomized rats may serve as an appropriate animal model to investigate BRONJ. Based on these findings, the role of progressive periodontal diseases in inducing BRONJ was investigated in this novel animal model. Progressive periodontitis was induced by ligature placement at the lower molar. Micro-CT analysis demonstrated that periodontitis significantly increased alveolar bone resorption at the ligatedsites, and the resorption was greatly attenuated by ZA treatment. Histological examination disclosed necrotic bone tissue with extensive empty lacunae. The results suggested that periodontal disease was a risk factor of BRONJ. ZA treatment may benefit the management of periodontitis, but increase the risk of developing BRONJ. To further understand the role of oral bacteria in the progression of BRONJ, An and ,two periodontopathic organisms frequently isolated from BRONJ lesions, were inoculated into the oral cavity of OVX rats with progressive periodontitis. Real-time polymerase chain reaction assay demonstrated that An and Fn were not routinely found in the oral cavity of rats, and ZA treatment did not promote the accumulation of these organisms. Micro-CT analysis disclosed that bacterial inoculation aggravated alveolar bone resorption and ZA treatment inhibited this change. Histological examination showed that ZA treatment greatly increased the risk of BRONJ, but bacterial inoculation had no further significant effect on this condition. In conclusion, the OVX rat model mimicking the remodeling process of human skeleton may serve as an appropriate animal model to investigate BRONJ. Periodontal disease is a risk factor for BRONJ. ZA treatment benefits the management of periodontitis; however, it increases the risk of developing BRONJ. Within the limitations of this model, progression of BRONJ did not worsen due to oral An and Fn inoculation in this experimental model.
DegreeDoctor of Philosophy
SubjectDiphosphonates
Periodontal disease
Jaws - Necrosis
Dept/ProgramDentistry
Persistent Identifierhttp://hdl.handle.net/10722/222198

 

DC FieldValueLanguage
dc.contributor.authorLi, Chunlei-
dc.contributor.author李春蕾-
dc.date.accessioned2016-01-02T23:29:58Z-
dc.date.available2016-01-02T23:29:58Z-
dc.date.issued2014-
dc.identifier.citationLi, C. [李春蕾]. (2014). Role of periodontal diseases in bisphosphonate-related osteonecrosis of the jaws. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5387954-
dc.identifier.urihttp://hdl.handle.net/10722/222198-
dc.description.abstractDespite the acknowledged benefit of bisphosphonates (BPs) in controlling bone disorders characterized by over-activity of osteoclasts-mediated bone resorption, a severe complication known as BPs-related osteonecrosis of the jaws (BRONJ) has been a major concern for both patients and clinicians. The study aimed to: 1) Investigate if ovariectomy(OVX) in rats could simulate intracortical remodeling process of the human skeleton; 2)Study the effect of zoledronic acid (ZA)on bone remodeling in the OVX rat model;3) Assess the role of periodontal diseases induced by ligature placement in the development of BRONJ on the OVX rat model;4) Evaluate the impact of Actinomyces naeslundii (An)and Fusobacterium nucleraide(Fn)inoculation on the progression of BRONJ in OVX rat model with periodontal diseases. In the preliminary study, Sprague-Dawly (SD) female rats received OVX surgery or sham operation and were treated with ZA or saline vehicle. After 12 weeks, rats were sacrificed and the mandibles were subjected to micro-computed tomography (micro-CT) and histomorphometric examinations. Intracortical remodeling in the mandible was significantlystimulated by OVX surgery, especially in the alveolar region (6-time higher than control), and remarkably inhibited by ZA treatment. The study for the first time demonstrated that OVX could stimulate intracortical remodeling in jawbones of rats. It provides hard evidence that ovariectomized rats may serve as an appropriate animal model to investigate BRONJ. Based on these findings, the role of progressive periodontal diseases in inducing BRONJ was investigated in this novel animal model. Progressive periodontitis was induced by ligature placement at the lower molar. Micro-CT analysis demonstrated that periodontitis significantly increased alveolar bone resorption at the ligatedsites, and the resorption was greatly attenuated by ZA treatment. Histological examination disclosed necrotic bone tissue with extensive empty lacunae. The results suggested that periodontal disease was a risk factor of BRONJ. ZA treatment may benefit the management of periodontitis, but increase the risk of developing BRONJ. To further understand the role of oral bacteria in the progression of BRONJ, An and ,two periodontopathic organisms frequently isolated from BRONJ lesions, were inoculated into the oral cavity of OVX rats with progressive periodontitis. Real-time polymerase chain reaction assay demonstrated that An and Fn were not routinely found in the oral cavity of rats, and ZA treatment did not promote the accumulation of these organisms. Micro-CT analysis disclosed that bacterial inoculation aggravated alveolar bone resorption and ZA treatment inhibited this change. Histological examination showed that ZA treatment greatly increased the risk of BRONJ, but bacterial inoculation had no further significant effect on this condition. In conclusion, the OVX rat model mimicking the remodeling process of human skeleton may serve as an appropriate animal model to investigate BRONJ. Periodontal disease is a risk factor for BRONJ. ZA treatment benefits the management of periodontitis; however, it increases the risk of developing BRONJ. Within the limitations of this model, progression of BRONJ did not worsen due to oral An and Fn inoculation in this experimental model.-
dc.languageeng-
dc.publisherThe University of Hong Kong (Pokfulam, Hong Kong)-
dc.relation.ispartofHKU Theses Online (HKUTO)-
dc.rightsThe author retains all proprietary rights, (such as patent rights) and the right to use in future works.-
dc.rightsCreative Commons: Attribution 3.0 Hong Kong License-
dc.subject.lcshDiphosphonates-
dc.subject.lcshPeriodontal disease-
dc.subject.lcshJaws - Necrosis-
dc.titleRole of periodontal diseases in bisphosphonate-related osteonecrosis of the jaws-
dc.typePG_Thesis-
dc.identifier.hkulb5387954-
dc.description.thesisnameDoctor of Philosophy-
dc.description.thesislevelDoctoral-
dc.description.thesisdisciplineDentistry-
dc.description.naturepublished_or_final_version-
dc.identifier.doi10.5353/th_b5387954-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats