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.

One of the commonest treatment options for replacing missing teeth is a root-form implant. Clinically, the key mechanical factor in achieving success is primary stability. This ex vivo study aims to evaluate whether osseodensification method will achieve good primary stability or the conventional drilling protocol. MethodsFresh iliac bone of the sheep was selected similar to D3 and D4 bone densities. A total of 22 osteotomy sites were prepared in the bone sample, of which 11 were prepared by osseodensification method (test group) and other 11 by conventional undersized drilling (control group). Primary stability was measured using insertion torque (IT), resonance frequency analysis (RFA), and reverse torque values (RTVs) by measuring implant stability quotient (ISQ). The recorded data were statistically analyzed using Statistical Package for the Social Sciences (SPSS) Version 22.0. The differences between groups were compared using the Mann-Whitney U test and independent t-test. The Pearson correlation coefficient test was performed to measure the linear relationship between two variables. The statistical significance level was established at p<0.05. ResultsWhen the correlation among IT, RTV, and ISQ was measured, a statistically significant correlation between IT and RTV (p=0.001) and between IT and ISQ (p=0.0001) was observed. A statistically significant (p=0.014) correlation between RTV and ISQ was also found. ConclusionOsteotomy prepared by osseodensification method showed higher IT, RTV, and ISQ values than the conventional undersized group.

To evaluate the better method of implant insertion into the osteotomy site in compromised quality bone for attaining optimal primary stability and thereby achieving the osseointegration for the ultimate success of implant. A total of 32 specimens (wood blocks) simulating D4 bone, were categorized into two groups. The osteotomy site was prepared as per the protocol and implants were placed till the level of the block. The insertion torque was quantified using digital Kratos torque meter. While the implants were inserted and abutments placed by hand ratcheting in the first group; they were motor-driven in the second group. Later pullout test was carried out in universal testing machine and results were analyzed using IBM SPSS Statistics for Windows Software, version 22 (IBM Corp., Armonk, NY, USA). The mean pull out force values obtained in implants placed by hand driven method were 624.375 N while the force values for implants inserted by motor-driven was 692.625 N. There was a statistically significant difference between hand and motor driven implant into the osteotomy site (p<0.05) between the groups. Of the different methods of implant insertion evaluated in this study, motor-driven imply to have a better primary stability indicating better integration with the bone to become a successful implant.

A BSTRACT Objective: The purpose of the study is to assess the method of implant insertion in D3 and D4 bones and influence of insertion torque for achieving better primary implant stability. Materials and Methods: A total of 32 specimens (wood blocks) simulating D4 and D3 bone were grouped into 1, 2, 3, and 4. In groups 1 and 3, the implant and abutment were placed by manual method while in groups 2 and 4 by motor-driven method. The osteotomy site was prepared as per the protocol for soft bone, and implants were placed till the implant platform was in flush with the surface of the block. After achieving a standard insertion torque of 40 N.cm, pullout test was carried out with a universal testing machine and results were analyzed by one-way analysis of variance. Results: An intergroup comparison of peak loads revealed an overall statistically significant difference ( P < 0.0001) with a mean of 442.638 N, maximum in group 4 and least (202.963 N) in group 1. The mean elongation break was found to be maximum in group 3 samples (81.67600%) and less in group 4 (37.15113%). Intergroup comparison of Young’s modulus was statistically significant ( P < 0.0001) with a mean value found to be minimum among group 1 samples (597.54750 MPa) and maximum in group 2 (1056.76463 MPa). An intergroup comparison of yield points was found to be maximum among group 4 samples (16.17238MPa) and least in group 1 (5.77438MPa). Conclusion: The D3 bone sample provided greater primary stability of implant than D4 bone samples, and the motor-driven implant seemed to have improved stability than that placed manually.

To determine the Oral Health-Related Quality of Life (OHRQoL) for post-treated fixed dental prostheses in selected sample of patients. Material and Methods: 120 patients treated with fixed dental prostheses, either single crowns or fixed partial dentures in maxillary or mandibular arches were asked to express their views about their quality of life. Patients' files were randomly selected from the archives of

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.

In today's restorative dentistry, replacement of missing tooth/teeth with implants has evolved as the most reliable and challenging eld through spectacular innovations with proven success. With the advent of tissue engineering, the outlook of implant dentistry has transformed especially with periodontal tissues. 'Ligaplants' unlike traditional implants have recently been introduced to address the shortcomings of conventional implants. Though there are pitfalls, future seems to be more promising with ligaplants that could revolutionize implant dentistry to a greater extent

Purpose: The purpose of this study was to evaluate the influence of water bath polymerization cycles on the color stability of unfilled polymethyl methacrylate (PMMA) teeth. Materials and methods: A total of 72 samples of unfilled PMMA were divided into two groups. Group 1 was subjected to a short curing cycle and group 2 to a long thermal curing cycle. Color measurements were done using a spectrophotometer and evaluated by the Commission Internationale de l’Eclairage (CIE) L*a*b* color system. Color difference (∆E) was calculated before and after thermal curing cycles and the data were statistically analyzed. Results: Group 2 teeth exhibited the highest ΔE values and color change to long curing cycle with significant difference between them. Conclusion: All the ΔE values were below 3.3, indicating that the color changes are not clinically perceptible.