College of Dentistry - M.Dent. Projects
Permanent URI for this collection
Browse
Recent Submissions
- ItemOpen AccessAssessing the Biomechanical Impact of Dentition Types and Craniofacial Forms on Intact and Fractured Mandibles(2024-08-26) Zakeri, Mahdi; Elgazzar, Reda (Dept. Oral and Maxillofacial Surgery); Bhullar, Rajinder (Dept. of Oral Biology); Todescan, Reynold (Dept of Prosthodontics); Rickey, Daniel (Dept of Radiology); Shah, AdnanCurrency, Oral and maxillofacial surgeon globally dealing with some challenges in Management of Mandibular fracture. It is imperative for clinician to have in depth understanding of biomechanic of the intact and fractured mandible to be able to improve the quality care and prevent further complications associated with the effectiveness of the open reduction and internal fixation of mandibular fracture. It is also important for clinician to have a thorough understanding of bone biology and the healing process, and how it is directly affected by mechanical and biological factors.
- ItemOpen AccessThe role of the oral microbiota and intrinsic host factors in peri-implant diseases: peri-implant mucositis versus peri-implantitis(2024-08-11) Rozenblit, Amit; Kelekis-Cholakis, Anastasia (Dentistry); Chelikani, Prashen (Oral Biology); Bhullar, Raj (Dentistry); Stavropoulou, ChrysiAim: To characterize and compare the role of the oral microbiota and host biomarkers in patients with peri-implant mucositis and peri-implantitis. Methods: Patients diagnosed with either peri-implant mucositis (N=13) or peri-implantitis (N=20) were recruited from the Dr. Sam Borden Graduate Periodontics Clinic at the University of Manitoba. Subgingival plaque samples and crevicular fluid samples were collected from diseased implant sites and healthy natural teeth to study the local microbiome and host biomarker profiles, respectively. 16 rRNA and ITS rRNA amplicon sequencing were performed to detect bacterial and fungal species. Eight different cytokines were isolated and analyzed: IL-1β, IL-2, IL-4, IL-6, IL8, IL-10, IFN-γ, TNF-α. Results: Bacterial differential abundance analysis indicated statistically significant differences in the abundance of 17 different bacterial taxa and species between sites with peri-implant mucositis and peri-implantitis, most notably Tannerella forsythia was significantly more abundant at sites with peri-implantitis compared to sites with peri-implant mucositis. Fungal differential abundance analysis indicated that Malassezia species were significantly reduced in sites with peri-implant mucositis compared to sites with peri-implantitis. Cytokine analysis indicated no statistically significant differences in the crevicular concentrations of any cytokines analyzed between the peri-implant mucositis and peri-implantitis groups. Conclusion: Peri-implant mucositis and peri-implantitis have similar microbial communities and cytokine profiles; however, the presence of certain bacterial and fungal species may play a role in the transition between peri-implant diseases.
- ItemOpen AccessRole of oral microbiota and intrinsic host factors in peri-implantitis – a pilot study(2022-04-26) Enghiad, Setareh; Stavropoulou, Chrysi (Dr. Gerald Niznick College of Dentistry); Cholakis, Anastasia (Dr. Gerald Niznick College of Dentistry); Chelikani, Prashen (Dr. Gerald Niznick College of Dentistry); Bhullar, RajIntroduction: Although many studies have evaluated microbial composition of peri-implant pockets, the role of mycobiome on peri-implantitis is not well established. Objectives: The aim of this study is to characterize the role of oral microbiota in peri-implant health and disease by determining the composition of the oral bacteriome and mycobiome from subgingival dental plaque, cytokine profile in the crevicular fluid, and to determine if there are any relationships between the oral microbiota, cytokine profile and peri-implant health and disease. Methods: Gingival crevicular fluid and subgingival plaque samples were collected from 20 periodontally healthy patients with healthy implants [Group H] and 9 periodontally healthy patients with peri-implantitis [Group P]. Eight IL-1β, IFN-γ, IL-2, IL-4, IL-6, IL-8, IL-10, and TNF-α were analyzed in crevicular fluid samples isolated from both groups. 16S rRNA and ITS rRNA amplicon sequencing was performed to detect bacterial and fungal species. Results: No statistically significant difference was found in concentrations of IL-2, IL-8, IL-10, and TNF-α. However, statistically significant differences were observed for IL-4 and IL-6. Alpha diversity analysis showed a significant difference between the groups H - Implant vs. P - Tooth and P - Implant vs. P - Tooth. Significant differences in species abundances were also observed between Group H and Group P. Candida parapsilosis and Aspergillus restrictus were significantly enriched in the Group P. Conclusions: To the best of our knowledge, this is the first time Aspergillus restrictus is related to peri-implantitis. Moreover, we found that the relative abundance of Candida parapsilosis is significantly higher in peri-implantitis sites. Our findings further challenge the concept that peri- implantitis is a bacterial disease with specific bacterial pathogens and strengthens the idea that bacterial invasion happens secondary to bone loss because of not very well understood processes such as foreign body reaction.
- ItemOpen AccessPrevalence of neurovascular structures in the anterior mandible and differences based on dentition, age and sex; a retrospective cone-beam computed tomography study(2023-07-13) Demers, Xavier; Huen, Galvin; Sunil, Mutalik (Dentistry); Kelekis-Cholakis, Anastasia (Dentistry); Hryniuk, Alexa (Human Anatomy and Cell Science); Bhuller, Raj (Dentistry); Stavropoulou, ChrysiObjective: To assess the prevalence of lingual and incisive vascular structures in the anterior aspect of the mandible and to see the effect sex, age and dentition status may have. Methods: A total of 191 anonymized cone-beam computed tomography (CBCT) scans were assessed by a single calibrated operator. Incisive canals and lingual canals present between the mental foramina were counted, with location, size, dentition status in the lower anterior mandibular sextant, as well as the distance between the alveolar crest for the most coronal centered lingual canal being noted. Results: Lingual canals were present in the midline area in 96% and in the lateral areas in about 25% of cases. Incisive canals had a prevalence under 10% for a given area in the mandible. Most canals observed were below 1 mm in diameter. The most coronal lingual canal in the center was 2 mm closer to the alveolar crest in females and in patients showing a degree of edentulism in the anterior mandible, with dentate patients also showing an increased number of lingual canals below 1 mm in size at the midline. Furthermore, aging appeared to impact the presence of lateral lingual canals. Although unclear, the dentition status could also affect the presence of larger incisive canals. Conclusions: The anterior mandible features several structures visible on CBCT scans. The present findings suggest that sex, age and dentition status could have an effect on their presence. As such, the previous variables should be considered when planning surgical interventions in the area.
- ItemOpen AccessA prospective evaluation of peri-operative glucocorticoid use in the management of cervicofacial infections of odontogenic origin(2023-07-12) McCoy, Ryan; Shah, Adnan (Dentistry); Elgazzar, Reda (Dentistry); Mutalik, Sunil (Dentistry); Bhullar, Raj (Dentistry); Shah, Adnan; Elgazzar, RedaOdontogenic cervicofacial infections requiring inpatient management are treated in a routine manner by oral and maxillofacial surgeons in Manitoba. After a standardized pre-operative workup, patients undergo surgical intervention including extraction of necessary teeth and incision and drainage of associated abscess(es). Patients are treated post-operatively with antibiotics, steroids, and medications for supportive care until appropriate for discharge. Benefits of intravenous corticosteroids in patients undergoing dentoalveolar and maxillofacial surgery include improved comfort, reduced post-operative edema, and shortened time to recovery. Corticosteroids also aid in reducing the risk of morbidity by limiting mass effect from edema and associated airway obstruction. In addition, their anti-inflammatory effect limits further swelling from manipulation of soft tissues during surgical procedures. Current literature supports the use of corticosteroids in the management of primary and deep space neck infections. However, corticosteroid dosing regimens are currently determined by the clinical judgment of the attending surgeon and are not standardized. The purpose of this study was to provide guidance for optimal dosing of methylprednisolone in the management of odontogenic cervicofacial infections. This prospective study followed the inpatient course of 28 patients with various cervicofacial infections of odontogenic origin. All patients were treated with a standardized surgical protocol, antibiotics, and steroids. Patients were randomized to receive one of two methylprednisolone dosing regimens. 14 patients were assigned to receive one dose of methylprednisolone 125mg IV at the time of surgery. The remaining 14 patients received one dose of methylprednisolone 125mg IV at the time of surgery and three consecutive doses of methylprednisolone 125mg IV every six hours post-operatively. Patients were evaluated at the time of hospital presentation and daily throughout admission. Outcomes evaluated included C-reactive protein (CRP) levels, white blood cell (WBC) count, length of hospital admission, and trismus. By examining differences in outcome success variables, the goal of this study was to support future evidence-based dosing decisions in the peri-operative treatment of inpatients in Manitoba. Data analysis showed a greater reduction in CRP throughout admission in the four-dose methylprednisolone group that was statistically significant. No significant difference in daily WBC count or trismus was found.