Background : It is difficult to achieve good primary stability of dental implants in soft bone, such as that in the posterior maxillae. Osseodensification (OD) burs, working in a non-subtractive fashion, condense the implant osteotomy bone in lateral direction and increase in the bone implant contact. Also, dental implants with deeper threads, and decreased thread pitch can increase initial bone implant anchorage. Methods: This study utilized 48 custom-made machined surface dental implants that were 13 mm long, with a major diameter of 4.5 mm and a minor diameter of 3.5 mm, a thread pitch of 1 mm, a thread depth of 0.5 mm, and a 4 mm long cutting flute at the apex. The implants were divided into 4 groups, each group was made of 12 implants with a different thread design; V-shaped, trapezoid, buttress, and reverse buttress. The implants were inserted in 4-mm thick cancellous bone slices obtained from the head of Cow femur bone. The ostoetomies were prepared by conventional drilling and by OD drilling. Each inserted implant was then tested for primary stability using the Periotest. The Periotest values (PTVs) for the implant stability were tabulated and analyzed using a chi square test at significance level p< 0.05. Results : The results of this this study revealed no statistically significant difference between the Periotest readings for the implants in each category placed in either the OD or the regular osteotomies. However, it has been found that the implants placed in regular drilling ostoetomies had a significantly better primary stability than the implants placed in OD osteotomies. Conclusions : It was concluded that OD is not necessary in situations where there is bone of good quality and quantity.

A new approach for segmenting different anatomical regions in dental Computed Tomography (CT) studies is presented in this paper. It is expected that the proposed approach will help automate different tissues regions by providing initial boundary points for deformable models or seed points for split and merge segmentation algorithms. Preliminary results obtained for dental CT studies of dentate and edentulous human-mandible are presented with finite element models divided by tetrahedral elements, which built based on actual CT data combined with triangulation equations. Identification of different anatomical regions set for mandible cortical and cancellous bones by generated 3D models by marching cubes technique.

Introduction: Laser micromachining of titanium and its alloys can create micro-grooves with sizes similar to cell diameter of about 10 μm. Its coating with arginine-glycine-aspartic acid (RGD) may enhance cellular spreading and adhesion. This study aimed to evaluate the effect of laser micro-grooving and laser micro-grooving combined with RGD coating on the strength of the dental implants/bone interface using destructive mechanical pullout testing in experimental animals. Materials and methods In this study, the test groups consisted of 1.5-mm diameter, 5-mm long laser-grooved and laser-grooved/RGD coated titanium alloy (Ti–6Al–4 V) rods, and the control group included plain titanium alloy (Ti–6Al–4 V) rods. These rods were implanted in the mandibles of New Zealand white rabbits for 2, 4, and 6 weeks. After sacrifice, the test and control specimens were retrieved for mechanical pullout testing. The DMA 7-e was used to pull the titanium rods out of the bone, the probe position was plotted versus time graph to monitor the test progression, and the static modulus versus time graph was viewed; such graphs was then transformed into tables. The results were analyzed using the Mann-Whitney test. Results: The laser-grooved/RGD coated rods had significantly higher pull-out strength than the laser-grooved and control rods. Additionally, the laser-grooved rods had significantly higher pull-out strength than control rods. Conclusion: Two novel surface treatments were used: laser micro-grooving and tri peptide RGD coating, both of which had different effects on the dental implant interface. Laser grooving improved peri-implant bone healing , whereas RGD coating facilitated earlier bone–implant adhesion and better mineralization.

Introduction: Competency‐based education (CBE) is thought to improve the quality of dental graduates than traditional education (TE). This study compared the students' final scores in clinical training of prosthodontics using CBE versus TE.Materials and Methods: This study enrolled 459 fourth‐ and fifth‐year undergraduate students. Of the participants, 231 students (143 males and 88 females) attended TE and 228 (128 males and 100 females) attended CBE. This study considered the final scores that the students achieved for their competency cases and compared it with the scores achieved during the TE process. Statistical analysis of results used the Mann–Whitney U test for nonparametric numbers.Results: The mean score of the clinical examination for all students in clinical prosthodontics courses was 81.4 (maximum and minimum scores: 95.0 and 41.3, respectively). The mean scores in the traditional and competency‐based education groups were 79.9 ± 6.48 and 82.9 ± 6.87, respectively. Scores in the competency education group (mean rank = 265.08) were statistically significantly higher than in the conventional education group (mean rank = 195.38) with U = 18,336, z = −5.631, and p < .001.Conclusions: The application of CBE allowed the students to achieve higher scores in prosthodontics than the TE.

Introduction Dental implants and extracoronal attachments were used with Kennedy class II implant assisted removable partial dentures (IARPD) without a major connector. strain gauges were used to detect the microstrains generated around the abutments and dental implants. Materials and Methods Thirty acrylic resin models of a mandibular class II Kennedy received 3 RPD designs; a clasp retained RPD in group I, a unilateral clasp retained RPD without a major connector supported by a dental implant placed once at the first molar and once at the second molar position in group II, and in group III, a clasp free RPD, with extracoronal attachments, supported by a dental implants placed in similar positions to group II. Strain gauges were used to determine which design generated more significant loads, and recorded microstrains were statistically analyzed using the Kruskal-Wallis and Mann-Whitney tests. Results Significantly greater loads around abutment teeth were reported in group II and group III than in group I. The distal placement of the implants resulted in significantly greater microstrains more than the mesial placement in groups II and III, and both placements were of more intensity in group II than in group III. Conclusions A Kennedy class II IARPD can be effectively altered to a bounded space prosthesis by placement of a dental implant in the first rather than the second molar position, and together with an extracoronal attachment, the clasp and major connector can be omitted once the edentulous span is short, and the clinical situation is favorable.