Standard Drill Research Articles

Kirschner wire creates more microdamage than standard or acrylic drill bits in the rabbit (Oryctolagus cuniculi) femur.

Histologically evaluate damage to rabbit femur after the creation of bicortical 1.5-mm-diameter holes using a standard surgical drill bit, an acrylic drill bit, and a Kirschner wire (K-wire). 10 femora (5 pairs) from skeletally mature female intact New Zealand white rabbits were used. The bone diaphyses were divided into 4 locations, systematically undergoing each test (surgical drill bit, acrylic drill bit, K-wire, and intact control). Four pairs were drilled using a mechanical testing machine, and 1 pair was drilled by hand. Cross-sections of the bone were stained en bloc with basic fuchsin for undecalcified histological evaluation. Damaged bone was reported as a percentage of a standardized area and categorized by location (cis- or transcortex), drill contact (entrance or exit of the cortex), and total damage (both cortices). The drilling method (hand vs mechanical testing machine) had no effect on histologic damage, so results were analyzed by combining all data. The K-wire demonstrated the greatest area of cracks/damage compared to both standard surgical and acrylic drill bits, whereas no difference in damage was noted between the 2 drill bits for all variables. The K-wire and drill bits caused microdamage; K-wire drilling created more microdamage than drill bits. The rabbit bone cortex is thin and brittle relative to dogs and cats, leading to failure during and after fracture fixation. The clinical failure of rabbit bone is at least partially caused by drill bits or K-wires causing microcracks.

Studies on surface roughness and axial thrust force of drilled holes in Mg-Zn-Ca bio-medical alloy

Mg-Zn-Ca alloy is a promising candidate for orthopaedic implants such as bone plates and screws, as it has a similar mechanical strength and elastic modulus to bone, and it degrades in the body without causing toxicity or inflammation. Drilling studies are necessary to optimize the drilling process parameters, to evaluate the machinability and surface integrity of Mg-Zn-Ca alloy, and to ensure the effective and efficient drilling for various applications in the medical and engineering fields. The present experimental study emphasizes the influence of Ca content, biofriendly coolants and their combined effect with standard drill bits on the surface quality and axial thrust force in the drilling operation of Mg-Zn-Ca alloy. The drilling parameters such as cutting speed, feed rate, standard tools, bio-compatible coolants were optimized with respect to the amount of Ca in the Mg-Zn alloy. The axial thrust force and average surface roughness of drilled holes were considered as response of the experiments. The drilled surfaces were measured for average surface roughness in the transverse direction along the centre path of the drilled hole and a qualitative analysis was also carried out using advanced confocal microscope. The results revealed that the cutting speed among continuous factors significantly influenced the axial thrust force and average surface roughness. The effect of categorical factors was assessed using a regression based ranking method. The results of statistical analysis revealed that high speed steel, and vegetable oil offered improved surface quality, whereas the coconut oil showed low axial thrust force. The liquid nitrogen showed high value of axial thrust force and average surface roughness due to the brittleness induced by cryogenic coolant before drilling operation.

External Mechanical Work Versus Energy Expenditure During on-Court Tennis Drills in Elite Adolescent Tennis Players

Abstract Purpose Tennis demands exceptional technical skills, speed, strength and endurance. Previous studies have highlighted the high energy expenditure during tennis drills due to constant directional changes. While metabolic monitoring and player tracking have been used to quantify exercise intensity and movements, mechanical efficiency (ME) in tennis remains poorly understood. This study aimed to investigate ME in tennis by combining metabolic and mechanical measurements during on-court drills. Methods Ten elite adolescent tennis players (males n = 5, females n = 5) performed a VO2max test on a treadmill and participated in three standard tennis drills, Spanish cross, lateral and inside out. During the tennis drill, full-body kinematics were captured, and energy expenditure was measured using a portable breath-by-breath gas analysis. ME was calculated for each drill, and individual differences were examined. Results Results revealed significant differences in energy expenditure and mechanical work between drills. ME was not associated with VO2max or running speed. highlighting the need to focus on other factors like strength, footwork technique, and neuromuscular training to enhance ME. Conclusion This study underscores the complexity of ME in tennis, with individual variations and where factors like footwork technique, muscular strength and motor abilities might influence ME.

Soft material drilling: A thermo-mechanical analysis of polyurethane foam for biomimetic bone scaffolds and optimization of process parameters using Taguchi method

Drilling is a widely employed technique in machining processes, crucial for efficient material removal. However, when applied to living tissues, its invasiveness must be carefully considered. This study investigates drilling processes on polyurethane foam blocks mimicking human bone mechanical properties. Various drill bit types (118° twist, 135° twist, spherical, and conical), drilling speeds (1000–1600 rpm), and feed rates (20–80 mm/min) were examined to assess temperature elevation during drilling. The Taguchi method facilitated systematic experiment design and optimization. Signal-to-noise (S/N) ratio and analysis of variance (ANOVA) identified significant drilling parameters affecting temperature rise. Validation was conducted through confirmation testing. Results indicate that standard twist drill bits with smaller point angles, lower drilling speeds, and higher feed rates effectively minimize temperature elevation during drilling.

Comparative evaluation of osseodensification drilling versus conventional drilling technique on dental implant stability: A systematic review.

The present systematic review compares the stability, crestal bone levels and efficacy of osseodensification (OD) drilling techniques for dental implant placement to traditional drilling methods. The Cochrane online library, PubMed, Scopus, and other well-known online resources are used in the research. Using a systematic review design, the current study examines published qualitative studies with an emphasis on analysis. Using precise keywords, a thorough search of pertinent databases was carried out in accordance with PRISMA standards. Studies testing dental implant stability, crestal bone levels and clinical results using both OD and traditional procedures were covered by the inclusion criteria. The risk of bias and quality of included studies was assessed using the Newcastle-Ottawa Scale for observational studies and the Cochrane Risk of Bias tool for randomized controlled trials. A total of 170 patients and 334 implants from Egypt, India, and Brazil were included in eight papers that made up the systematic review. In several clinical situations, osseodensification outperformed standard drilling in terms of implant durability, bone development, and torque data. Statistical analysis presented the lowest risks, while blinded outcome assessment, allocation concealment, random sequence generation, incomplete outcome data and experimental technique revealed higher risks. Bias assessment found various risks across different components. The thorough examination of eight papers demonstrates that osseodensification is a technique with great promise in the field of dental implants. It exhibits superior torque values, bone development, and stability when compared to traditional drilling. The overall results highlight the potential of osseodensification to improve clinical outcomes and advance the science of dental implantology, even in the face of variances in bias concerns.

Numerical Study of Coolant Flow Phenomena and Heat Transfer at the Cutting-Edge of Twist Drill

Cutting tool coolant channels play a pivotal role in machining processes, facilitating the efficient supply of cooling agents to high-stress areas and effective heat dissipation. Achieving optimal cooling at the tool’s cutting-edge is essential for enhancing production processes. Experimental investigations into tribological stress analysis can be limited in accessing complex tool–workpiece contact zones, prompting the use of numerical modelling to explore fluid dynamics and tribology. In this study, the coolant flow dynamics and heat dissipation in drilling operations were comprehensively investigated through computational fluid dynamics (CFD) modelling. Four twist drill models with varying coolant channel arrangements were studied: standard model drill, standard model drill with notch, profile model drill, and profile model drill with notch. Two distinct approaches are applied to the coolant inlet to assess the impact of operating conditions on fluid flow and heat dissipation at the cutting-edge. The findings emphasize that cutting-edge zones have insufficient coolant supply, particularly in modified drill models such as the standard model drill with notch and profile model drills with and without notch. Moreover, enhanced coolant supply at the cutting-edge is achieved under high-pressure inlet conditions. The standard model drill with a notch exhibited exceptional performance in reducing thermal load, facilitating efficient coolant escape to the flute for improved heat dissipation at the cutting-edge. Despite challenges like dead zones in profile models, the standard-with-notch model yielded the most promising results. Further analyses under constant pressure conditions at 40 and 60 bar exhibited enhanced fluid flow rates, particularly at the cutting-edge, leading to improved heat dissipation. The temperature distribution along the cutting-edge and outer corner demonstrated a decrease as the pressure increased. This study underscores the critical role of both coolant channel design and inlet pressure in optimizing coolant flow dynamics and heat transfer during drilling operations. The findings provide valuable insights for designing and enhancing coolant systems in machining processes, emphasizing the significance of not only coolant channel geometry but also inlet pressure for effective heat dissipation and enhanced tool performance.

Comparative Analysis of the Effects of Two Different Drill Designs on Insertion Torque and Primary Stability during Osteotomy - An In Vivo Animal Study.

This study aims to evaluate the effects of two drill designs on insertion torque (IT) and implant stability quotient (ISQ) during osteotomy. This in vivo animal study involved eight female New Zealand white rabbits divided into two groups: Group A underwent osteotomy using standard drills from the Zimmer surgical kit, and Group B used Densah drills. IT values and ISQ were taken during and after implant placement. Rabbits received premedication, and postoperative care was provided. Significant differences in peak IT were observed between the two groups, with Group B demonstrating a statistically significant advantage. However, no significant differences were found in ISQ between the groups. This study highlights the potential benefits of osseodensification in enhancing primary stability during osteotomy.

Primary Stability and Fracture Resistance of Zirconia and Titanium Implants: A Paired Comparative In Vitro Study.

Compare Neodent Zi® zirconia implants' insertion torque (IT) and removal torque (RT) with Neodent Alvim® titanium. Measure the maximum torque supported by the zirconia implant until its fracture (MT) and the maximum torque sustained by the assembler of this implant (MTA) until its fracture. In this in-vitro study twenty four implants were used. Two groups of implants with the same macrogeometry and from the same manufacturer were compared, Zirconia (n=12) and Titanium (n=12). Implant bed preparations were completed in bovine ribs following a standardized drilling protocol. Then, the insertion torque (IT), removal torque (RT), maximum torque to fracture (MT) and maximum torque to fracture of the assembler (MTA) were completed using a calibrated torque meter. Data was presented using descriptive statistics including means, standard deviations (SD), medians, and quartiles. The Shapiro-Wilk test was used to verify data normality and the Wilcoxon test was used to evaluate differences between groups. Statistical significance was established as p < 0.05. Zirconia implants showed: IT 89.33 ± 31.18 Ncm and RT 84.89 ± 32.92 Ncm. Titanium implants showed: IT 77.58 ± 28.96 Ncm and RT 76.75 ± 31.29 Ncm without significant differences (p>0.05). In relation to fracture under rotational force, the zirconia implants fractured at 106.17 ± 22.54 Ncm, and the implant assembly fractured at 84.00 ±13.14 Ncm. Neodent Zi® implants showed stability but lower fracture torque than Alvim® titanium. As the fracture values of the assembler were significantly lower than the fracture values of the zirconia implants, it can be stated that, as recommended by the manufacturer, they act as a safety measure during installation.

Ramsay 1 and Ramsay 2, learnings from the first natural hydrogen exploration wells in Australia

In October and November 2023, Gold Hydrogen, an ASX listed natural hydrogen explorer, drilled Ramsay 1 and Ramsay 2, the first natural hydrogen exploration wells in Australia. Twinning an historic well, the Ramsay Oil Bore 1 well in PEL687 in South Australia, the objective of the Ramsay 1 and Ramsay 2 wells was to find movable naturally generated hydrogen in the subsurface and establish the presence of a commercially attractive natural hydrogen resource base. This paper highlights some of the learnings from the process of designing and executing these natural hydrogen exploration wells and how the initial hurdles of demonstrating the presence of a hydrogen resource were overcome during the drilling phase. Using modified standard drilling technology and dedicated hydrogen detection tools (calibrated real time mud gas analysis), Gold Hydrogen has shown that exploration for natural hydrogen resources can be done safely and cost effectively. The main learnings included the application of a calibrated hydrogen detection methodology to derive a pseudo hydrogen saturation log and the successful selection of drilling mud and casing compliant with long term hydrogen exposure. As global drilling for natural hydrogen is still in its infancy, these modifications to the exploration well design and execution could have a significant impact on future drilling for this highly attractive carbon free energy source. With a program of seismic data acquisition and follow-up wells planned for 2024, Gold Hydrogen is leading a group of Australian natural hydrogen explorers, who are trying to unlock commercial natural hydrogen resources in the world.

K-wire is more damaging than standard or acrylic drill bits when evaluating torsional properties of rabbit (Oryctolagus cuniculi) femurs.

The objective of this study is to compare drilling variables and torsional mechanical properties of rabbit femora after bicortical drilling with a 1.5-mm standard surgical drill bit, acrylic drill bit, and K-wire. 24 pairs of rabbit femora. After drilling under controlled axial displacement rate, each bone was biaxially loaded in compression followed by rapid external torsion to failure. Maximum axial thrust force, maximum drill torque, integral of force and displacement, change in temperature, maximum power spectral density of the torque signal, torque vibration, and torque and angle at the yield and failure points were collected. Pre- and postyield stiffness, yield and failure energies, and postyield energy were calculated. The work required to drill through the cis- and transcortices (integral of force and displacement) was greater for the K-wire, followed by the acrylic and then standard drill bits, respectively. The K-wire demonstrated higher maximum torque than the drill bits at the ciscortex, and the force of drilling was significantly greater. The vibration data was greater with the acrylic and standard drill bits than the K-wire. There was no difference in torsional strength between drilling types. Mechanical differences exist between different drill bits and K-wire and demonstrate that the K-wire is overall more damaging than the surgical drill bit.

Conventional Versus Osseodensification Drilling in the Narrow Alveolar Ridge: A Prospective Randomized Controlled Trial.

Background Conventionally, undersized osteotomies were used to increase initial bone-to-implant contact to achieve primary stability in implantology. This is particularly evident in regions with low bone density. The potential for severe bone compression and ischemia poses a challenge to secondary stability. Instead, lateral bone compaction is caused by the idea of osseodensification. Research on the potential benefits of this method for narrow ridges is lacking. This study aimed to determine if the osseodensification drilling technique affects primary stability and how much the alveolar ridge expands following implant site preparation. Methodology A total of 30 participants aged 20 to 80 years were included in this randomized controlled clinical investigation. Each participant was randomly assigned to one of the following two groups: one that received standard drill preparation, and another that received osseodensification drill preparation. Implant stability using implant stability quotient values, crest width, apical width (5 mm from crest), and bone density were assessed both before and after six months using cone-beam computed tomography. Results Osseodensification impacted the width at the apex (5 mm from the crest) and radiographic bone density, adding to the quality, but did not affect implant stability and crestal width after osseointegration. The mean difference in conventional and osseodensification groups was 0.46 and 0.68 mm, respectively, concerning the crestal width. Moreover, the mean difference was 0.74 and 0.58 mm for conventional and osseodensification groups, respectively, concerning the width at the apex (5 mm from the crest). Conclusions This study demonstratesthat the osseodensification process increased both the radiographic bone density and the width at the apex, demonstrating that osseodensification drilling techniques allow for the placement of implants with larger diameters innarrow alveolar ridges.

Standard and experimental drilling fluids’ effect on the response of the larvae of bivalve Hiatella sp.

Behavior of the larvae of common genus of marine bivalve mollusk Hiatella sp. was tested at the presence of the standard drilling fluid and the water-based drilling fluid containing brown alga Saccharina latissima as biodegradable component. Standard drilling fluid (based on polyanionic cellulose and xanthan gum) is currently used at Prirazlomnaya offshore ice-resistant oil platform. A series of experiments have been performed with live larvae (young and elder stages, ~250 µm and ~350 µm, respectively) at 6.7 and 20 mL/L concentrations of the drilling fluids and in control. Larvae tended to spend more time with closed valves when exposed to standard drilling fluid. Larvae exposed to drilling fluid with Saccharina latissima extract were characterized by significantly higher activity comparing both to control group and to standard drilling fluid solution. Elder larvae were more sensitive to standard drilling fluid, being under stress from the very beginning of the experiment (3 hours of exposure) to the end (48 hours of exposure + 24 hours in native sea water). Young larvae tend to be more resistant both to standard drilling fluid and drilling fluid with Saccharina latissima extract; this may promote their better survival. Possible biological consequences of using natural and environmentally friendly extract of brown algae on pelagic larvae of benthic species is discussed.

Correlation between the size of released titanium particles and changes in the surface of dental implants during insertion into bone blocks: an in vitro study.

This study investigated the size and amount of titanium particles immediately released following dental implant insertion into bovine bone blocks and aimed to correlate them with the surface roughness of the implants. Twelve bone blocks were prepared from bovine mandibles. Six tapered (group A) and 6 cylindrical (group B) dental implants were inserted into the bone blocks under water irrigation, following the standard drilling protocol. After insertion, the implants were immediately removed from the bone. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and atomic force microscopy were performed to investigate the released titanium particles and implant surface roughness, respectively. The amount of titanium ions in the irrigation water was measured using inductively coupled plasma mass spectrometry. Dynamic light scattering (DLS) was used to determine the size range of the released titanium particles. The percentages of titanium content on the surface of implants decreased in both groups after implantation into bone blocks. SEM-EDX analysis confirmed the presence of titanium particles embedded in the implanted bone bed. Group B implants showed significantly higher concentrations of titanium ions in the collected water than group A implants (0.868 and 0.565 µg/L, respectively). Group A implants demonstrated high pre-implantation surface roughness, which led to a much greater decrease in post-implantation surface roughness than was observed for group B implants. DLS analysis showed that the titanium particles released from group A implants were within the nano-size range, whereas those released from group B implants were within the micro-size range. Dental implant placement leads to a decrease in implant surface roughness and the immediate release of titanium particles into the peri-implant bone. Variations in the size range and amount of released particles were correlated with implant surface roughness. This finding has clinical implications and warrants additional in vivo studies.

A novel pneumatic drill for bone biopsy under MRI imaging.

Bone biopsies are currently conducted under computed tomography (CT) guidance using a battery-powered drill to obtain tissue samples for diagnosis of suspicious bone lesions. However, this procedure is suboptimal as images produced under CT lack soft tissue discrimination and involve ionizing radiation. Therefore, our team developed an MRI-safe pneumatic drill to translate this clinical workflow into the MR environment, which can improve target visualization and eliminate radiation exposure. We compare drill times and quality of samples between the 2 drills using animal bones. Five porcine spare rib bones were obtained from a butcher shop. Each bone was drilled twice using the Arrow OnControl battery-powered drill and twice using our pneumatically actuated drill. For this study, we used an 11-gauge bone biopsy needle set with an internal core capturing thread. A stopwatch recorded the overall time of drilling for each specimen obtained. All 20 samples collected contained a high-quality inner core and cortex. The total average time for drilling with the pneumatic drill was 8.5s (+ / - 2.5s) and 7.1s (+ / - 1.4s) with the standard battery-powered drill. Both drills worked well and were able to obtain comparable specimens. The pneumatic drill took slightly longer, 1.39s on average, but this extra time would not be significant in clinical practice. We plan to use the pneumatic drill to enable MRI-safe bone biopsy for musculoskeletal lesions. Biopsy under MRI would provide excellent lesion visualization with no ionizing radiation.

Modified orbitozygomatic craniotomy with a single burr hole in the alternative sphenoid ridge keyhole

BackgroundOne-piece modified orbitozygomatic approach (OZA) is an extended version of the pterional approach that also includes orbital walls and frontal process of the zygomatic bone. For this craniotomy one burr hole must be placed in MacCarty keyhole and another - in the temporal region. ObjectiveTo develop a technique of the one-piece modified OZA with single a burr hole in the alternative sphenoid ridge keyhole that allows access to orbit, anterior cranial fossa and middle cranial fossa and apply it intraoperatively. MethodsA single human head specimen was used. The dissection was performed using standard surgical instruments high-speed Stryker drill. Every stage of the approach was photographed. We also report a surgical case of a patient with orbital cavernous hemangioma that was resected using the described technique. ResultsThe technique of the one-piece modified OZA with a single burr hole in the alternative sphenoid ridge keyhole is described, and its advantages and limitations are analyzed. The technique is used to totally resect an orbital cavernous hemangioma with good functional and cosmetic result. ConclusionModified OZA with a single burr hole in the sphenoid ridge keyhole is possible and may be an alternative to the classic technique. The advantages of this variation are the placement of just one burr hole and the preservation of a larger portion of the orbital roof. The latter facilitates better bone reconstruction and better cosmetic outcome. Disadvantages are the difficulty of identifying the location of the sphenoid ridge keyhole and risk of damaging the dura.

The Influence of Internally Cooled Drill Bits on Cutting Dynamics and Workpiece Hardness Monitoring in Stone Machining

Drill bits with internal cooling capabilities are still not employed in stone machining practices within shop floor environments. Therefore, a conventional industrial drill bit used in stone machining was subject to a redesign wherein an axial cooling channel was machined throughout its body. A comparison was drawn between the standard drill bit without cooling capabilities and the redesigned drill bit, which used compressed air as a cooling medium. The experiment was performed by drilling three types of stone samples varying in hardness with nine combinations of cutting speed and feed rate. During the machining process, two types of process signals were continuously measured—namely, cutting forces and vibrations. Additionally, the cutting edges of the drill bits were inspected after a specific number of drilling cycles using a vision system. The primary objective of this study was to compare the cutting forces and tool wear dynamics achieved by those two drill bits. Furthermore, the usage of vibration signals in the classification of stone hardness during machining with an internally cooled drill bit was additionally analyzed. The results of this study unveiled improvement in minimizing cutting forces, vibrations, and the intensity of tool wear when utilizing an internally cooled drill bit. Even though the machining system generally exhibited lower vibrations, vibration signals again demonstrated commendable efficacy in classifying stone hardness.

Оценка точности метода измерения сопротивления сверлению древесины в дендрохронологических исследованиях

One of the promising methods for determining physical and mechanical properties and structure of wood is the method based on the measurement of drilling resistance. Limitations of application of the method of measuring drilling resistance in dendrochronological studies are related to a number of factors that have a significant impact on the accuracy of determining the variation of physical and mechanical properties of wood within annual layers: the depth of drilling, its direction relative to the fibers, and the speed parameters of the drilling process. In order to assess the accuracy of measuring the radial growth of pine wood (Pinus sylvestris L.) with moisture content of 6–8 %, the ResistYX device and standard thin drill bits were used. On the basis of comparative analysis of radial wood growth determined by the optical method and the method of measuring resistance to drilling, it was found that in order to obtain accurate data on growth with a correlation coefficient greater than 0.7, it is recommended to measure no more than 17 annual layers on one sample, which corresponds to an average total width of annual layers of 36.6 mm. The influence of the main reasons for the decrease in the accuracy of radial growth determination by the drilling resistance measurement method was studied: geometrical parameters of the cutting part of a thin drill bit, deviation of the drilling direction from the specified one, impossibility of precise determination of the strictly radial drilling direction, wood flaws, as well as friction of the drill shank when the drilling depth increases. To increase the accuracy of the method of measuring drilling resistance in dendrochronological studies it is proposed to develop a method including the use of a special or newly developed tool for more accurate determination of the core and radial drilling of wood or round timber; to increase the rigidity of the thin drill bit; to provide the required fixation of the thin drill bit during its initial contact with wood and inside the device. Further studies in this direction will be associated with the assessment of measuring accuracy for the radial growth of coniferous wood by the feeding force for drill bit penetration. For citation: Chernov V.Yu., Sharapov E.S., Gaisin I.G. Evaluation of the Accuracy of Wood Drilling Resistance Measurement Method in Dendrochronological Studies. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 5, pp. 135–150. (In Russ.). https://doi.org/10.37482/0536-1036-2023-5-135-150

Clinical Comparison of Vascular Bleeding Time Creep Between Osseodensification and Conventional Drilling of Implant Osteotomy Sites.

This study compared the onset of vascular bleeding between osseodensification and conventional drilling of implant osteotomy sites. Patients with type III trabecular bone requiring a single missing tooth replacement were included and allocated to either Group A (test) or Group B (control). In Group A, the osseodensification group (OD), an implant osteotomy was carried out using Densah Burs (Versah) in the counterclockwise direction; in Group B, the standard drilling group (SD), Densah Burs were run in the clockwise direction. An endoscope was introduced into the osteotomy to visualize and measure the time taken for initiation of bleeding (BI) and for blood to fill the osteotomy site (BF). A total of 40 osteotomy sites (23 in the maxilla and 17 in the mandible) were included in this cross-sectional study. The mean age of study participants was 50.1 ± 8.28 years. The mean BI time for Groups A and B was 18.54 ± 2.48 seconds and 16.89 ± 1.92 seconds, respectively (P = .02); the mean BF time for Groups A and B was 41.92 ± 3.19 seconds and 37.95 ± 2.73 seconds, respectively (P < .001). Osseodensification does not seem to negatively affect or induce loss of bone vascularity. Clinicians should note that osseodensified sites might take slightly longer to fill with blood following an osteotomy.

The Effect of Temperature on Filtration Loss and Mud Cake on The Concentration of Corn Starch Using the KCl-Polymer Sludge System

Drilling mud is a type of fluid that can help smoothing a drilling. The function of the drilling mud in the drilling process is to lift the drilling cutting. In this laboratory research, corn starch was used as a substitute for starch to reduce filtration loss. Corn starch is made by cleaning, drying, grinding, and sieving. The purpose of this research is to make mud with the addition of corn starch. its effect on filtration loss and mud cake at two temperature conditions. In this study the use of corn starch to be mixed into the mud with concentrations of 3 grams, 5 grams, 7 grams, 9 grams, and 11 grams. Accordingly, it can be seen which mud composition complies with the standard drilling mud specifications. Laboratory test results showed that the addition of corn starch additives caused a decrease in filtration loss for each difference in concentration and temperature. With the addition of 11 grams of corn starch, filtration loss decreased from 6.2 ml to 4.4 ml at 80°F, and it decreased from 5.2 ml to 3.9 ml at 200°F. In addition, corn starch additives cause the thickness of the mud cake formed to decrease. At a temperature of 80 oF the thickness of the mud cake decreased from 0.76 mm to 0.46 mm, while at a temperature of 200 oF it decreased from 0.62 to 0.42 mm. Based on the research results, corn starch additives and temperature influence changes in filtration loss and mud cake.

Influence of Implant Macro-Design, -Length, and -Diameter on Primary Implant Stability Depending on Different Bone Qualities Using Standard Drilling Protocols-An In Vitro Analysis.

(1) Background: Primary implant stability is vital for successful implant therapy. This study explores the influence of implant shape, length, and diameter on primary stability in different bone qualities. (2) Methods: Three implant systems (two parallel-walled and one tapered) with various lengths and diameters were inserted into polyurethane foam blocks of different densities (35, 25, 15, and 10 PCF) using standard drilling protocols. Primary stability was assessed through insertion torque (IT) and resonance frequency analysis (RFA). Optimal ranges were defined for IT (25 to 50 Ncm) and RFA (ISQ 60 to 80). A comparison of implant groups was conducted to determine adherence to the optimal ranges. (3) Results: Implant macro-design, -length, and -diameter and bone block density significantly influenced IT and RFA. Optimal IT was observed in 8/40 and 9/40 groups for the parallel-walled implants, while the tapered implant achieved optimal IT in 13/40 groups (within a 25-50 Ncm range). Implant diameter strongly impacted primary stability, with sufficient stability achieved in only one-third of cases despite the tapered implant's superiority. (4) Conclusions: The findings highlight the need to adapt the drilling protocol based on diverse bone qualities in clinical practice. Further investigations should explore the impact of these adapted protocols on implant outcomes.