Finite Element Analysis and Its Applications in Dentistry

Finite Element Analysis or Finite Element Method is based on the principle of dividing a structure into a finite number of small elements. It is a sophisticated engineering tool, which has been used extensively in design optimization and structural analysis first originated in the aerospace industry to study stress in complex airframe structures. This method is a way of getting a numerical solution to a specific problem, used to analyze stresses and strains in complex mechanical systems. It enables the mathematical conversion and analysis of mechanical properties of a geometric object with wide range of applications in dental and oral health science. It is useful for specifying predominantly the mechanical aspects of biomaterials and human tissues that cannot be measured in vivo. It has various advantages, can be compared with studies on real models, and the tests are repeatable, with accuracy and without ethical concerns

Alteration in Serum Lipid Profile Pattern in Oral Squamous Cell Carcinoma and Potentially Malignant Disorders

Objective: To evaluate and compare lipid profile level in oral submucous fibrosis (OSMF), oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC) patients. Material and Methods: Thirty histopathologically diagnosed subjects each of OL, OSMF, OSCC were recruited along with 30 healthy controls. 5ml of venous blood is collected and estimated using standard diagnostic kits. Results: The mean of Total cholesterol level in controls was 219.03 mg%, in OSCC, OL and OSMF was 142.89 ± 10.21mg%, 155.44 ± 17.63 mg% and 180.60 ± 13.25 mg%, respectively. The mean low-density lipid level in controls was 137.24 mg and in OSCC, OL and OSMF groups were 109.28 ± 2.16 mg%, 126.63 ± 0.85 mg% and 119.15 ± 0.93 mg%, respectively. The mean of high-density lipid level in controls, OSCC, OL and OSMF was 42.87 ± 0.42 mg%, 36.50 ± 2.31 mg%, 21.13 ± 0.77 mg% and 28.37 ± 1.11mg%, respectively. The mean of very low density lipids level in controls, OSCC, OL and OSMF was 30.12 ± 1.51 mg%, 17.24 ± 0.80 mg%, 22.25 ± 0.93 mg% and 25.89 ± 0.43 mg%, respectively. The mean triglyceride level in controls, OSCC, OL and OSMF was 118.80 ± 9.47 mg%, 91.2 ± 3.03 mg%, 105.05 ± 2.96 mg% and 106.19 ± 3.09 mg%, respectively. Conclusion: Lipid profile levels could be early indicators of precancer and cancer

Assessment of Bite Forces in Restored Teeth with Different Commonly Used Restorative Materials: A Comparative Study

Objective: To evaluate and compare bite force (BF) in permanent first molars restored with glass ionomer cement (GIC), composite and amalgam, and normal contralateral permanent first molars. Material and Methods: BF was recorded in decayed permanent first molars, which were filled with GIC (n=30), composite (n=30), and amalgam (n=30), and in healthy contralateral first molars (n=90) with Force Transducer Occlusal Force Meter and compared. Results: BF was significantly higher in normal teeth on the contralateral side compared to teeth restored with GIC and composite. However, in patients with amalgam restoration, though it was less compared to that on the contralateral side, it was not statistically significant (p>0.05). Conclusion: Restoring teeth with various filling materials may improve bite force. In the present study, it was found that the teeth restored with amalgam had higher bite forces in comparison to the other restorative materials used. However, it was not comparable to that observed in the normal tooth (control) on the contralateral side

Knowledge, Attitude and Practices Regarding Consumption of Carbonated Soft Drinks Among the Dental Students: A Cross-Sectional Study

Objective: To assess and evaluate the knowledge, attitude, and practices regarding the consumption of carbonated drinks among dental students. Carbonated drinks are pervaded by carbon dioxide and have more adverse effects since they are acidic in nature. Nowadays, these are consumed more widely globally, causing many systemic diseases; diabetes and obesity are common. Material and Methods: This study includes 204 individuals belonging to the age group of 18-26 years. A self-structured objective type cross-sectional questionnaire survey was conducted to assess the knowledge, attitude, and practice of dental students regarding carbonated drinks. The participants were instructed to mark the most appropriate correct answer from the given list of close-ended type questions. Results: Of 204 dental students, the study population includes 125 female and 79 male students. 98.5% of the students knew about carbonated drinks, while 1.5% were unaware. Conclusion:  Most participants preferred to have carbonated drinks even with their awareness about the ill effects of these drinks. Possible implications by the government authorities may probably increase awareness among the population

Periodontal Clinical Parameters as a Predictor of Bite Force: A Cross-Sectional Study

Objective. To investigate the correlation of periodontal parameters and bite force in different stages of periodontitis after phase I periodontal therapy. Methods. Periodontal clinical parameters such as mobility, attachment loss, gingival recession, and percentage of bone remaining were recorded at the mandibular first molar region after phase I therapy in subjects categorized according to the stage of periodontitis. Corresponding bite force was recorded at the first mandibular molar region using a bite force device after phase I therapy. ANOVA test was used to assess the significant difference among different groups. Pearson correlation coefficient was used to assess the correlation between measured variables. Results. The ANOVA test represents that there is no statistical significant difference between the bite force in stage I, stage II, and stage III type of periodontitis. A strong positive correlation was found (r=0.537) between bite force and percentage of remaining alveolar bone support whereas negative correlation was observed in measured parameters such as mobility (r=−0.0181), attachment loss (r=−0.608), and gingival recession (r=−0.435). Conclusion. Among all periodontal clinical parameters, the percentage of remaining alveolar bone is the strong predictor of bite force and mobility; attachment loss and gingival recession cannot predict the bite force in the first molar region. Bite force is variable in different stages of periodontitis

Evaluation of Stress Distribution and Force in External Hexagonal Implant: A 3-D Finite Element Analysis

Purpose: To analyze the stress distribution and the direction of force in external hexagonal implant with crown in three different angulations. Materials and Methods: A total of 60 samples of geometric models were used to analyze von Mises stress and direction of force with 0-, 5-, and 10-degree lingual tilt. Von Mises stress and force distribution were evaluated at nodes of hard bone, and finite element analysis was performed using ANSYS 12.1 software. For calculating stress distribution and force, we categorized and labeled the groups as Implant A1, Implant A2, and Implant A3, and Implant B1, Implant B2, and Implant B3 with 0-, 5-, and 10-degree lingual inclinations, respectively. Inter- and intra-group comparisons were performed using ANOVA test. A p-value of ≤0.05 was considered statistically significant. Results: In all the three models, overall maximum stress was found in implant model A3 on the implant surface (86.61), and minimum was found on model A1 in hard bone (26.21). In all the three models, the direction of force along three planes was maximum in DX (0.01025) and minimum along DZ (0.002) direction with model B1. Conclusion: Maximum von Mises stress and the direction of force in axial direction was found at the maximum with the implant of 10 degrees angulation. Thus, it was evident that tilting of an implant influences the stress concentration and force in external hex implants