The Experts below are selected from a list of 2190 Experts worldwide ranked by ideXlab platform
Mohd Faizal Ali Akhbar - One of the best experts on this subject based on the ideXlab platform.
-
Numerical and experimental investigations on temperature and thermal damage in cortical bone Drilling
2020Co-Authors: Mohd Faizal Ali AkhbarAbstract:Bone Drilling is a typical operation in the myriad of surgeries in the orthopedics, oral and maxillofacial, neurological, and otolaryngology. Friction and shear deformation energy during the Drilling surgery generates extreme heat in the Drilling hole, which increases the bone temperature. Furthermore, the low thermal conductivity of bone escalates the bone temperature and causes the irreversible death of the bone cells (thermal osteonecrosis). Thermal osteonecrosis loosens fracture fixations (orthopedic), tooth implants (oral and maxillofacial), and cochlear implants (otolaryngology), which could cause revision surgeries. These surgeries necessitate additional costs and healing time. Moreover, to add insult to injury, thermal osteonecrosis could even cause permanent disability to the patients when it involves nerve injuries. Drilling parameters (rotational speed, feed, Drilling hole depth, and Drill bit diameter) and Drill bit geometries (point angle, helix angle, and web thickness) have been identified as two main factors that can be manipulated to reduce the bone temperature. Therefore, this thesis aims at reducing the thermal damage in bone Drilling by using optimal Drilling parameters (ODP) and improved Drill bit geometries (IDG). In order to determine the ODP and IDG, approaches including numerical, experimental, and statistical were adopted. Human cortical bone and Surgical Drill bit models were developed using commercially available finite element method (FEM) software, DEFORM-3D. In terms of Drilling parameters, the rotational speed of 50 rev/min to 400,000 rev/min, feed of 0.0100 mm/rev to 0.1875 mm/rev, Drilling hole depth of 0.5 mm to 5.0 mm, and Drill bit diameter of 0.5 mm to 6.0 mm were investigated. Whereas, for Drill bit geometries, the point angle of 60-160°, helix angle of 10-36°, and web thickness of 5-50 % were investigated. The simulation results were validated then with the experimental bone Drilling using a conventional milling machine. A new method called sum of weightage was introduced to determine the suitable ranges for optimization study. From the sum of weightage results, the ranges for Drilling parameters (rotational speed = 50-500 rev/min and feed = 0.1600-0.1875 mm/rev) and Drill bit geometries (point angle = 118°-140°, helix angle = 30°-36°, and web thickness of 10 %-18 %.) for optimization study were selected. Then, the response surface methodology (RSM) and multi-objective optimization studies were performed to determine the ODP and IDG. Results revealed that the ODP could be obtained with a rotational speed of 50 rev/min and feed of 0.1750 mm/rev. Whereas, the optimal Surgical Drill bit (stainless steel 316L) can be constructed with a point angle of 131.8°, helix angle of 36°, and a web thickness of 11.8 %. The proposed ODP can significantly reduce the thermal damage compared with the recommendations from the previous studies (maximum bone temperature elevation (Tmax) = 8.9–85.8 °C, osteonecrosis diameter (OD) = 5.16 mm-10.07 mm, and osteonecrosis depth (OH) = 3.35-5.50 mm). Furthermore, the IDG can reduce thermal damage more than the existing Surgical Drill bit (Tmax = 2.3 °C, OD = 1.16 mm, and OH = 1.96 mm). When ODP and IDG are combined, the thermal damage can further be reduced up to 1.2 °C to 9.3 °C for Tmax, 4.45 mm for OD, and 2.22 mm for OH compared with when using ODP and IDG individually. The significant original contributions from this thesis come from several areas. This work has determined the suitable bone model as the replacement for human bone in bone Drilling (in terms of temperature elevation). Next, new ODP and IDG were recommended to reduce significant thermal damage. This research extends our knowledge of thermal osteonecrosis prevention and will serve as a base for future studies in the automation of bone Drilling surgery
-
Multi-objective optimization of Surgical Drill bit to minimize thermal damage in bone-Drilling
Applied Thermal Engineering, 2019Co-Authors: Mohd Faizal Ali Akhbar, Ahmad Razlan YusoffAbstract:Abstract The existing Surgical Drill bit is not fully optimized to protect against thermal damage during the bone-Drilling surgeries. In this study, the optimal Drill bit design that induces minimum thermal damage is attained through rigorous Drilling simulations and statistical analysis approaches. For thermal damage analysis, maximum bone temperature and osteonecrosis diameter are designated as responses, whereas Drill bit point angle, helix angle and web thickness are selected as the designing parameters. These parameters and responses are evaluated and optimized using response surface methodology (RSM) coupled with desirability analysis. The optimized Drill bit then is compared with the typical Surgical Drill bit in Drilling simulation of human cortical bone. Simulation results reveal that the proposed Drill bit design effectively reduces the maximum bone temperature (15.2%) and osteonecrosis diameter (10.5%). These results are validated with experimental bone-Drilling and data from previous literature. This work demonstrates the feasibility of applying finite element method (FEM) to study the clinical issues in bone-Drilling research and find the optimal solutions prior to clinical trial. Furthermore, this work provides an important opportunity to revise and redesign the existing Surgical Drill bit for a minimum thermal damage in bone surgeries.
-
Drilling of bone: Effect of Drill bit geometries on thermal osteonecrosis risk regions
SAGE Publications Ltd, 2019Co-Authors: Mohd Faizal Ali Akhbar, R. A. YusoffAbstract:Bone-Drilling operation necessitates an accurate and efficient Surgical Drill bit to minimize thermal damage to the bone. This article provides a methodology for predicting the bone temperature elevation during Surgical bone Drilling and to gain a better understanding on the influences of the point angle, helix angle and web thickness of the Drill bit. The pro- posed approach utilized the normalized Cockroft–Latham damage criterion to predict material cracking in the Drilling process. Drilling simulation software DEFORM-3D is used to approximate the bone temperature elevation correspond- ing to different Drill bit geometries. To validate the simulation results, bone temperature elevations were evaluated by comparison with ex vivo bone-Drilling process using bovine femurs. The computational results fit well with the ex vivo experiments with respect to different Drill geometries. All the investigated Drill bit geometries significantly affect bone temperature rise. It is discovered that the thermal osteonecrosis risk regions could be reduced with a point angle of 110 to 140, a helix angle of 5 to 30 and a web thickness of 5% to 40%. The Drilling simulation could accurately estimate the maximum bone temperature elevation for various Surgical Drill bit point angles, web thickness and helix angles. Looking into the future, this work will lead to the research and redesign of the optimum Surgical Drill bit to minimize thermal insult during bone-Drilling surgeries
E J Dixo - One of the best experts on this subject based on the ideXlab platform.
-
evaluation of intraoperative cone beam computed tomography and optical Drill tracking in temporal bone surgery
Laryngoscope, 2013Co-Authors: Oba M Erovic, Michael J Daly, Harley H L Cha, Adria L James, Lake C Papsi, David D Pothie, E J DixoAbstract:OBJECTIVES/HYPOTHESIS: A prototype system for intraoperative cone beam computed tomography (CBCT) imaging has been developed and augmented with real time optical tracking of a Surgical Drill. We hypothesize that this system provides sufficient accuracy for guidance of temporal bone surgery. STUDY DESIGN: Basic research. METHODS: Measurements of Drill localization accuracy using CBCT imaging were obtained with a custom three-dimensional calibration object. Integrated CBCT imaging and Drill tracking were prospectively evaluated on 12 cadaver temporal bones. Six inexperienced and six experienced surgeons conducted four Surgical tasks: cortical mastoidectomy, posterior tympanotomy, cochleostomy, and a translabyrinthine approach to the internal auditory canal. Questionnaires provided expert feedback on tracking accuracy and system usability. RESULTS: Target registration error measurements of Drill tracking accuracy and precision yielded a mean of 0.76 mm, a maximum of 1.30 mm, and a standard deviation of 0.21 mm. Anatomical landmark identification tasks (e.g., facial nerve, incus, semicircular canals, cochlea) provided additional validation of system accuracy. The usability and utility of the guidance system were positively rated by both groups of surgeons, with further modifications underway to improve tracking line of sight and registration workflow. Experienced but in particular inexperienced surgeons indicated significant benefits in cases involving extensive disease, abnormal anatomy, and loss of anatomical landmarks. CONCLUSIONS: The integration of intraoperative CBCT imaging with optical tracking provides sufficient accuracy to localize anatomical structures within the temporal bone using an otological Drill. Future studies will explore the role of this technology in complex oncological resections, in surgery for congenital anomalies, and as a tool for teaching.
Ahmad Razlan Yusoff - One of the best experts on this subject based on the ideXlab platform.
-
Multi-objective optimization of Surgical Drill bit to minimize thermal damage in bone-Drilling
Applied Thermal Engineering, 2019Co-Authors: Mohd Faizal Ali Akhbar, Ahmad Razlan YusoffAbstract:Abstract The existing Surgical Drill bit is not fully optimized to protect against thermal damage during the bone-Drilling surgeries. In this study, the optimal Drill bit design that induces minimum thermal damage is attained through rigorous Drilling simulations and statistical analysis approaches. For thermal damage analysis, maximum bone temperature and osteonecrosis diameter are designated as responses, whereas Drill bit point angle, helix angle and web thickness are selected as the designing parameters. These parameters and responses are evaluated and optimized using response surface methodology (RSM) coupled with desirability analysis. The optimized Drill bit then is compared with the typical Surgical Drill bit in Drilling simulation of human cortical bone. Simulation results reveal that the proposed Drill bit design effectively reduces the maximum bone temperature (15.2%) and osteonecrosis diameter (10.5%). These results are validated with experimental bone-Drilling and data from previous literature. This work demonstrates the feasibility of applying finite element method (FEM) to study the clinical issues in bone-Drilling research and find the optimal solutions prior to clinical trial. Furthermore, this work provides an important opportunity to revise and redesign the existing Surgical Drill bit for a minimum thermal damage in bone surgeries.
Verica Pavlic - One of the best experts on this subject based on the ideXlab platform.
-
thermal evaluation by infrared thermography measurement of osteotomies performed with er yag laser piezosurgery and Surgical Drill an animal study
Materials, 2021Co-Authors: Dragana Gabric, Damir Aumiler, Marko Vuletic, Elizabeta Gjorgievska, Marko Blaskovic, Mitko Mladenov, Verica PavlicAbstract:The bone healing process following osteotomy may vary according to the type of Surgical instrumentation. The aim of the present in vivo study was to determine thermal changes of the bone tissue following osteotomies performed by Er:YAG laser ablation in contact and non-contact modes, piezoelectric surgery, and Surgical Drill using an infrared thermographic camera. For each measurement, the temperature before the osteotomy-baseline (Tbase) and the maximal temperature measured during osteotomy (Tmax) were determined. Mean temperature (ΔT) values were calculated for each osteotomy technique. The significance of the difference of the registered temperature between groups was assessed by the ANOVA test for repeated measures. Mean baseline temperature (Tbase) was 27.9 ± 0.3 °C for contact Er:YAG laser, 29.9 ± 0.3 °C for non-contact Er:YAG laser, 29.4 ± 0.3 °C for piezosurgery, and 28.3 ± 0.3 °C for Surgical Drill. Mean maximum temperature (Tmax) was 29.9 ± 0.5 °C (ΔT = 1.9 ± 0.3 °C) for contact Er:YAG laser, 79.1 ± 4.6 °C (ΔT = 49.1 ± 4.4 °C) for non-contact Er:YAG laser, 29.1 ± 0.2 °C (ΔT = −0.2 ± 0.3 °C) for piezosurgery, and 27.3 ± 0.4 °C (ΔT = −0.9 ± 0.4 °C) for Surgical Drill. Statistically significant temperature changes were observed for the non-contact laser. The results of the study showed beneficial effects of the osteotomy performed by the Er:YAG laser used in the contact mode of working as well as for piezosurgery, reducing the potential overheating of the bone tissue as determined by means of infrared thermography.
Katleen Vandamme - One of the best experts on this subject based on the ideXlab platform.
-
effect of insertion torque on titanium implant osseointegration an animal experimental study
Clinical Oral Implants Research, 2015Co-Authors: Joke Duyck, Rutger Roesems, Marcio Vivan Cardoso, Toru Ogawa, Germana De Villa Camargos, Katleen VandammeAbstract:Objective To evaluate the effect of implant insertion torque on the peri-implant bone healing and implant osseointegration. Material and methods Bilaterally in the tibia of five adult New Zealand white rabbits, 20 implants were installed, subdivided into four groups, corresponding to two insertion torque conditions (low, 50 Ncm) and 2 experimental periods (2 weeks vs. 4 weeks of healing). The implant insertion torque was determined by the Surgical Drill diameter relative to the implant diameter. Implant osseointegration was evaluated by quantitative histology (bone-to-implant contact with host bone [BIC-host], with neoformed bone [BIC-de novo], with both bone types [BIC-total], and peri-implant bone [BA/TA]). Every response was modelled over time using GEE (general estimation equation) with an unstructured variance–covariance matrix to correct for dependency between the measurements from one animal. The statistical significance level of α = 0.05 was applied. Results Significantly, more BIC-host and BIC-total were recorded for H implants compared with L implants after 2 week of healing (P = 0.010 and P = 0.0001, respectively). However, this result was no longer found for the extended healing period. Furthermore, BIC-total significantly increased over time for L implants (P < 0.00001). In contrast, the significant increase in BA/TA over time was found for H implants (P < 0.01). Finally, H insertion torque led to an increased BA/TA after 4 week of healing (P < 0.02) compared with the L insertion protocol. Conclusion L insertion torque implants installed in the rabbit tibial bone osseointegrate with considerable de novo bone formation. This bone neoformation enables L implants to catch up, already during the early osseointegration stage, the initial inferior amount BIC contact compared with that of H implants. A negative impact of the created strain environment accompanying H insertion torque implant installation on the biological process of osseointegration could not be observed, at least not at tissue level.