Diamond Points Research Articles

Volumetric analysis after caries excavation with caries detecting dyes and chemomechanical caries removal agents using 3D scanner-a randomised clinical trial

AimThis research aimed to use an extra-oral 3D scanner for conducting volumetric analysis after caries excavation using caries-detecting dyes and chemomechanical caries removal agents in individuals with occlusal and proximal carious lesions.MethodsPatients with occlusal (A1, A2, A3) and proximal carious lesions (B1, B2, B3) were treated with the conventional rotary technique, caries detecting dyes (CDD) and chemomechanical caries removal (CMCR) method on 90 teeth (n = 45 for each). Group A1, B1: Excavation was performed using diamond points. Group A2, B2: CDD (Sable Seek™ caries indicator, Ultradent) was applied and left for 10 s, and then the cavity was rinsed and dried. For caries removal, diamond points or excavators were used. Group A3 and B3: BRIX3000 papain gel was applied with a micro-brush for 20 s and was activated for 2 min, and then the carious tissue was removed with a sharp spoon excavator. Post-excavation cavity volume analysis was performed using a 3D scanner. The time required and the verbal pain score (VPS) for pain were scored during excavation. Post-restoration evaluation was performed at 1, 3, and 6 months FDI (Federation Dentaire Internationale) criteria.ResultsComparison of age, time and volume with study groups were made using Independent Sample’ t’ test and one-way analysis of variance (ANOVA) for two and more than two groups, respectively. Using Cohen’s Kappa Statistics, evaluators 1 and 2 agreed on caries removal status aesthetic, functional and biological properties at different follow-ups. The chi-square test revealed that the rotary groups [A1(2.5 ± 0.4 min) B1(4.0 ± 0.4 min)] had significantly less (p = 0.000) mean procedural time than CDD [A2(4.5 ± 0.4 min) B2(5.7 ± 0.4 min)] and CMCR [A3(5.4 ± 0.7 min) B3(6.2 ± 0.6 min)] groups. The CMCR group showed better patient acceptance and less pain during caries excavation than the rotary and CDD groups. CMCR group showed significantly less mean caries excavated volume(p = 0.000). Evaluation of restoration after 1-, 3-, and 6-month intervals was acceptable for all the groups.ConclusionBrix3000 helps effectively remove denatured teeth with less pain or sensitivity. The time required for caries removal was lowest in the rotary method and highest in the brix3000 group, while the volume of caries removed was the lowest for brix3000 and highest for the rotary group.

Comparative Efficacy of Smart Burs vs Conventional Burs in Removing Infected Dentin and Preserving Affected Dentin in Primary Teeth: A Randomised Control Study

Introduction: With the advent of time, the removal of caries has shifted from hand instruments to rotary instruments. A disadvantage of conventional burs is that they non selectively lead to over-preparation. A new polymer bur can be substituted to eliminate these undesirable effects. Aim: To compare and evaluate the efficacy of smart burs and conventional burs in removing infected dentine while preserving affected dentin in carious lesions in primary teeth. Materials and Methods: This was a double-blinded randomised controlled trial conducted in the Department of Paediatric and Preventive Dentistry at Swargiya Dadasaheb Kalmegh Smruti Dental College and Hospital, Nagpur, Maharashtra, India over a period of three months, from August 2023 to October 2023. A total of 40 children aged 6-12 years were selected and evaluated for caries removal efficacy using visual and tactile criteria, which were further confirmed by dye application and numerically scored. Group 1 included 20 children who underwent caries excavation with smart burs, while Group 2 included 20 children who underwent the procedure with diamond points. Statistical analysis was conducted using descriptive and inferential statistics, specifically the Chi-square test. Results: A total of 40 children aged 6-12 years were divided into two groups: Group 1 comprised 11 boys and 9 girls, whereas Group 2 included 10 boys and 10 girls. Of these, 12 cases (60%) showed complete caries removal after the first application of dye, regardless of which burs was used. However, 4 cases (20%) showed some residual caries when using smart burs, while 6 cases (30%) exhibited residual caries with diamond points at the base of the cavity preparation. Additionally, there were 4 cases (20%) with caries present at the base and/or in one wall of the cavity preparation when using smart burs, compared to 2 cases (10%) with conventional burs. Nonetheless, there was no statistically significant difference between the smart burs and the conventional diamond points regarding caries removal. Conclusion: It can be concluded that smart burs are equally effective in removing soft caries compared to conventional methods. Although the results were statistically insignificant, polymer burs were found to be more convenient and can be considered a viable alternative to conventional caries removal techniques.

In Vitro Comparative of the Cutting Efficiency and Smear Layer of Ceramic Burs, Conventional Tungsten Carbide Burs and Diamond Stone

Purpose: To compare the cutting efficiency and the smear layer of three different types of burs ceramic, tungsten carbide and diamond stone. Materials and Methods:135 mica-based glass ceramics (Vita blocs Mark II) blocks were used to valuate cutting efficiency by weight loss method. Five points from each type of burs: Cera Bur (komet, Brasseler, Germany): K59, Tungsten Carbide tapered Bur (komet, Brasseler, Germany): H2 010 and diamond points (komet, Brasseler, Germany): 957AM 314 010, were used for cutting procedures. Each bur had made 30 seconds duration cut, each bur was used three times. Cutting was performed under standardized protocol using a specially designed machine for this purpose. Twelve unerupted human third molars were used to obtain Dentin slabs. Cutting was performed using the same protocol and the smear layer created was observed by means of scanning electron microscope. Results: The values of weight loss were: 0.18 ± 0.08 gm, 0.40 ± 0.07 and 0.50 ± 0.07 gm for each bur respectively. Less dense smear layer was observed with the Cera Bur when compared to the tungsten carbide and diamond burs. Conclusion: The new tapered fissure ceramic bur can be considered a promising tool for minimally dentistry, while providing a minimal reduction of the sound, hard tooth substance.

Diagnosis and Assessment of Dental Caries Using Novel Bioactive Caries Detecting Dye Solution.

The goal of materials should be early caries detection, removal of carious lesions, and reduction of dentin hypersensitivity. Thus, the study aims to determine the efficacy of a bioactive caries detecting dye (BCD) for the diagnosing and mechanical removal of occlusal and proximal dental caries. Patients with occlusal (A1, A2) and proximal carious lesions (B1, B2) were treated with the rotary technique and BCD solution on 120 teeth (n = 60 for each). Group 1: Excavation was performed using diamond points. Group 2: 0.5 mL of BCD solution was scrubbed for 20 sec and excavation was performed with a sharp spoon excavator. Post-excavation cavity volume analysis was performed using a 3D scanner. The time required, VAS for pain, VAS for facial expression, and sound eye motor scoring were scored during excavation. Post-restoration evaluation was performed at 3, 6, and 12 months (FDI criteria). The chi-square test revealed that the A1 (197.90 30.97 s) and B1 (273.06 69.95 s) had significantly less mean procedural time than the A2 (292.13 44.87 s) and B2 (411.86 88.34 s). BCD (A2, B2) group showed good patient acceptance, less pain during caries excavation VAS (p = 0.001, FACE (p = 0.001), and SEM (p < 0.001) analysis than the rotary group. There was a statistically insignificant difference between groups immediately (p = 0.235), (p = 0.475) and after 24 h (p = 0.561), (p = 0.688). Color score, hardness of excavated surface, and caries removal score for occlusal and proximal groups showed insignificant differences between the groups. BCD group showed significantly less mean caries excavated volume for the occlusal group (p = 0.003) as compared to the proximal group (p = 0.417) evaluated by 3D scanner. Evaluation of restoration after 3-, 6-, and 12 months intervals (Occlusal caries group (p = 0.247), (p = 0.330), and (0.489) and Proximal caries group (p = 0.299), (p = 0.594), and (0.494)) was acceptable for both the groups. BCD helps in identification of dental caries clinically, radiographically, and in effective removal of denatured teeth with less pain or sensitivity.

Comparative evaluation of two different cold Sterilization techniques on carbide burs and diamond points

Background: Infection control is a major issue in medicine and dentistry because of concern over communicable diseases transmitted in health care settings. The present study was conducted for comparatively evaluating various Cold Sterilization Techniques on Carbide Burs and Diamond Points. Materials &amp; methods: The present study was conducted for comparatively evaluating various Cold Sterilization Techniques on Carbide Burs and Diamond Points. Two disinfectant solutions were used: 2% glutaraldehyde and 5.2% sodium hypochlorite. Carbide group formed Group A while diamond burs formed the group B. Collection of total 40 tooth samples was done .i.e. 20 samples in each group ; further both the study groups consisted of two subgroups each as per the type of disinfectant solution. The bacterial count was evaluated for both before and after disinfection. All the results were recorded and analysed by SPSS software. Results: Sodium hypochlorite sterilization technique was slightly better in comparison to Glutaraldehyde technique. Also carbide burs were associated with less microbial growth. Conclusion: Sodium hypochlorite sterilization technique and carbide burs were slightly better for clinical usage.

EVALUATION OF THE MARGINAL ACCURACY IN PORCELAIN FUSED TO METAL COPINGS FABRICATED IN TWO DIFFERENT FINISH LINES USING THREE DIFFERENT DIE MATERIALS -A STEREOMICROSCOPIC ANALYSIS AS A COMPARATIVE STUDY

Introduction: In the 20th century itself innovative techniques and materials were introduced for the fabrication of restorations that accurately fit over the prepared surface of the tooth. To fabricate these restorations, various materials like metals, alloys, resins, and ceramics were used. Regarding the different materials, metals and alloys have the advantage of superior strength, but for color, it is esthetically not acceptable. Due to a lack of esthetic value metals are replaced by ceramics.&#x0D; Objective: To compare the effect of two different marginal geometries shoulder and deep chamfer on metal-ceramic copings fabricated with the use of three different die materials Conventional Type IV Gypsum, epoxy resin, resin-modified Gypsum (Synthetic Gypsum).&#x0D; Methods: Two ivorine mandibular first molars were prepared using diamond points for receiving Full veneer porcelain fused to metal restorations. The two designs of circumferential finish evaluated in this study were shoulder and deep chamfer.&#x0D; Results: Tests specimen fabricated on 3 groups of die material each having shoulder and deep chamfer finish line were analyzed under a stereomicroscope at four points, following results of vertical marginal gaps in μm were recorded.&#x0D; Conclusion: It is thus concluded from the above study that dies fabricated using three different materials in two different finish lines i.e shoulder and deep chamfer did not exhibit a statistically significant difference in terms of marginal accuracy and either of these finish lines can opt for fabrication of metal-ceramic restorations.

Comparative evaluation of marginal adaptation of two root end filling materials in root end preparation done with diamond points and ultrasonics - An in vitro SEM study

The aim of the present study was to evaluate the marginal adaptation of two bioceramic root end filling materials in root end preparation done with diamond points and ultrasonics under scanning electron microscope.: 56 single rooted extracted human teeth were collected and decoronated to create a standardized length of 14mm and were then endodontically treated. The treated tooth were resected 3mm from the apex at 90 degree angle to long axis of the tooth.The samples were then randomly divided into two groups, group I and group II of 28 samples each. Group I and group II were further divided into subgroup A and subgroup B of 14 samples each. Root end preparations in subgroup A of both the groups were done using ultrasonic tips and in subgroup B of both the groups root end preparations were done using diamond points and In Group I all the root end preparation were filled with MTA(Angelus) and in group II with Biodentine.The apical portions of the roots were then sectioned to obtain 1mm thick transversal sections, scanning electron microscopy was used to determine the adaptations of the root end filling materials with the dentin. Two way Anova and Tukeys Multiple Posthoc test was used for statistical data analysis.: Lowest mean marginal gap of 0.46 micron meter seen with Group II (a) and highest marginal gap of 0.83micron meter seen with Group I (b), which were statistically significant (P&amp;#60;0.05).: Biodentine group, root end preparation done using ultrasonics showed best marginal adaptation than all the other tested groups.

Origin, Use and Meaning of the Innovation Diamond

This document seeks to present the instrument known as the DIAMOND OF INNOVATION and its “green version”, reveals the genesis from the results shown with the generation of the collection of books called: ASIAN FIRMS. Using these eight books makes it possible to discover the business model of the central countries (PR China, Republic of India) and Southeast Asia (Japan, South Korea, R. China-Taiwan, Singapore, Vietnam), focusing on continuous Innovation. This process, which tested and perfected the instrument, is accompanied by companies from the industrial and Colombian primary sectors. The tool shows its ability to establish a diagnosis in a city, country, company in terms of Innovation and establish a strategy based on the eight points of the Diamond and accompany it with a hierarchy or strategic priority. To this end, the use of secondary tools is established, such as the STRATEGIC MOTHER MATRIX. It detects the behavior of the leading countries for each of the Diamond points, becoming “good practices”, and determines the backwardness or practices to improve, prioritizing each strategy to be developed, seeking to advance on the subject of Innovation. With the advancement of research, sponsored from the beginning by the Universidad Piloto de Colombia and its Business Administration program and research partners such as Grupo SASA and some farms in the Ubaté valley (Department of Cundinamarca), dedicated to the main production focused on In dairy, the “green” version of the Innovation Diamond is tested and launched, its reason for being: to prevent Innovation in a country, city, company, from being accepted simply for being Innovation, without considering its impact in the environment.

Use of extra-fine crosscut bur to produce horizontal texture in composite resin restorations

Reproducing the developmental lobes and perikymata of the anterior teeth of young patients with composite resin restorations is a clinical challenge.1-3 Different finishing and polishing systems and techniques are available, although a standard protocol is lacking. The selection of the correct instruments will depend on the position of the tooth and the type of surface to be reproduced. Multibladed and diamond rotary instruments and abrasive rubber points are commonly used for this procedure.4

Comparative evaluation of the efficiency of caries removal using various minimally invasive techniques with conventional rotary instruments using cone beam computed tomography: An in vitro study

Aim: The aim of this in vitro investigation was to assess the most efficient minimally invasive technique (MIT) by comparing the change in volume after caries removal using cone beam computed tomography (CBCT) and the time taken for each technique. Materials and Methods: Forty human extracted molars, stored in 0.1% thymol solution, with carious lesions extending into the dentin were used in the study. The caries status of dentin was judged initially by visual inspection and probing and confirmed by caries detector dye. A pre-scan CBCT was performed before assessing the volume of the carious lesion. Teeth were assigned into four groups (n = 10): Group 1 = Carisolv gel, Group 2 = Carie Care, Group 3 = ultrasonic tips, and Group 4 = slow-speed rotary instruments. The caries removal was performed according to the manufacturer’s instructions. Time taken was recorded for each method. A postoperative scan was conducted, and volumetric analysis was carried out. The amount of removal of sound tooth structure was assessed to determine the most MIT. Descriptive and inferential statistics were used to analyze the data. The intergroup volume change of caries was carried out using the Kruskal–Wallis test, whereas comparison within the group was carried out using Wilcoxon signed-rank test. The assessment of time taken during each procedure was analyzed with one-way analysis of variance and Tukey honest significant difference test. The results were tabulated accordingly. Significance was set at P value ≤ 0.05. Results: The chemomechanical agents (Carisolv and Carie Care) showed minimal change in volume when compared to conventional diamond points. The time taken with conventional diamond point was minimum, and it was maximum for ultrasonic tips. Conclusion: Chemomechanical caries removal is the most minimalistic approach when compared to the other techniques.

ИССЛЕДОВАНИЕ ВЛИЯНИЯ УЛЬТРАЗВУКОВОЙ ПРАВКИ НА ЭНЕРГО-СИЛОВЫЕ ПОКАЗАТЕЛИ ВРЕЗНОГО КРУГЛОГО ШЛИФОВАНИЯ

The authors carried out the experimental study of the influence of ultrasonic dressing of grinding wheels on the energy-force indicators of the grinding process. The study showed the degree of ultrasonic dressing influence on the cylindrical plunge grinding indicators in the automatic cycle of processing. The authors identified that ultrasonic dressing of grinding wheels with a dressing tool executing vibrations with the frequency of 22 kHz and the amplitude of 10…15 µm allows decreasing the supporting face of a grinding wheel texture 4-5 times through the increase of the abrasive grains quantity with the relatively sharp micro-edges and microcracks. It is shown, that the distinctive features of formation of the grinding wheel working surface texture during ultrasonic dressing ensure the reduction of cutting perpendicular force about by 30 % during the whole period of grinding wheel life as well as allows increasing the wheel life 1.5…2 times. It is noted that during the ultrasonic dressing, the abrasive grains break due to the repetitive impact loading creating numerous cutting edges and microcracks at the less dressing depth than after traditional dressing. In the result of interference of sinusoidal trajectories of diamond points of a dressing tool, on a grinding wheel, a certain cammed texture forms, what decreases the wheel bearing surface. The existence of two texture components explains the higher cutting power of a grinding tool compared to the traditional dressing.

The effect of abrading and cutting instruments on machinability of dental ceramics.

The aim was to investigate the effect of machining instruments on machinability of dental ceramics. Four dental ceramics, including two zirconia ceramics were machined by three types (SiC, diamond vitrified, and diamond sintered) of wheels with a hand-piece engine and two types (diamond and carbide) of burs with a high-speed air turbine. The machining conditions used were abrading speeds of 10,000 and 15,000 r.p.m. with abrading force of 100 gf for the hand-piece engine, and a pressure of 200 kPa and a cutting force of 80 gf for the air-turbine hand-piece. The machinability efficiency was evaluated by volume losses after machining the ceramics. A high-abrading speed had high-abrading efficiency (high-volume loss) compared to low-abrading speed in all abrading instruments used. The diamond vitrified wheels demonstrated higher volume loss for two zirconia ceramics than those of SiC and diamond sintered wheels. When the high-speed air-turbine instruments were used, the diamond points showed higher volume losses compared to the carbide burs for one ceramic and two zirconia ceramics with high-mechanical properties. The results of this study indicated that the machinability of dental ceramics depends on the mechanical and physical properties of dental ceramics and machining instruments. The abrading wheels show autogenous action of abrasive grains, in which ground abrasive grains drop out from the binder during abrasion, then the binder follow to wear out, subsequently new abrasive grains come out onto the instrument surface (autogenous action) and increase the grinding amount (volume loss) of grinding materials.

Comparison of Various Cold Sterilization Techniques on Routinely used Carbide Burs and Diamond Points

ABSTRACT Aim The aim of this study is to compare the various cold sterilization techniques for sterilizing dental burs and diamond points by assessing the microbial growth in culture media on them before and after sterilization. Materials and methods The following four disinfectants were used: 2% glutaraldehyde, 5.2% sodium hypochlorite, hydrogen peroxide, and 70% ethanol. There were two main groups taken as group I-carbide burs and group II-diamond burs. A total of 48 samples were collected, 12 samples per disinfectant. Each sample has two burs collected from same patient. One acts as control group which means only microbial count was deter- mined without disinfection. The other one would be determined as microbial count before and after disinfection. The microbial assessment was done using brain heart infusion (BHI) broth and counted by plating in chocolate blood agar and MacConkey agar. Results The obtained results were statistically analyzed by one-way analysis of variance (ANOVA) test and post hoc test. The results revealed that there was statistically significant difference between sodium hypochlorite and surgical spirit, sodium hypochlo- rite and hydrogen peroxide. There was no statistically significant difference between sodium hypochlorite and glutaraldehyde. Conclusion The results of this study revealed that sodium hypochlorite and glutaraldehyde are most effective than hydro- gen peroxide, and surgical spirit is the least effective disinfectant. However, there was clinical significance in level of disinfection of all four disinfectants. How to cite this article Ranganathan S, Manvi S, Gopalakrishna S, Renukanath CK. Comparison of Various Cold Sterilization Tech- niques on Routinely used Carbide Burs and Diamond Points. Int J Prosthodont Restor Dent 2017;7(3):97-102.

Molecular dynamics simulation of nanoscale contact and sliding processes for probes with different tip radius of curvature

Three-dimensional molecular dynamics (MD) simulations were carried out to study the contact and sliding processes between diamond points with different tip radius of curvature and surfaces of single crystal copper. The material deformation, abrasion mechanism, lattice defects, the force of contact process, and the sliding friction process were investigated. The simulation results show that the contact force, dislocations, and stacking fault defects, increase during the contact process with increasing contact depth or tip radius of curvature. The dislocations emit along the $$ \left[ {10\bar{1}} \right] $$ and $$ \left[ {\bar{1}0\bar{1}} \right] $$ direction and then a glide band is formed. It was also found that a greater tip radius of curvature results in a larger groove and more material deformation. The normal force and friction increase with increasing tip radius of curvature, but the coefficient of friction decreases. The stacking faults spread along the sliding direction and increase with increasing tip radius of curvature. In addition, the number of upheaval atoms increases as the radius of tip curvature or sliding distance increases.

CONDUTA CLÍNICA PROFISSIONAL QUANTO AO USO E DESCARTE DE PONTAS DIAMANTADAS

Purpose.The purpose of this study was to check dentists´opinions about reasons of wear and the criteria used for disposal of diamond burs. Methods.114 dentists answered a self-explanatory questionnaire,whichwas subsequently submitted to a descriptive analysis of results. Results.According to the data gathered, it was noted that most of participants considers that amalgam and enamel are the primary cause of diamond burs’wear (60% and 29%, respectively). Furthermore, most individuals have indicated that sterilization processes accelerated the aging(78%). The primary causes of diamond burs disposal: darkening (79%),increase in timeand strength necessary to wear structures (79%),decrease in the concentration of diamonds on the tip of the bur (78%), and presence of residues (49%).Conclusion.Moreknowledgein sterilization processes and quantity of diamond points uses is need due to its prevalence in clinical practice.

Profilometric study to compare the effectiveness of various finishing and polishing techniques on different restorative glass ionomer cements

Objective: The aim of the present study was to evaluate the effect of various finishing and polishing techniques on the surface roughness of different types of glass ionomer (GI) restorative cements. Materials and Methods: Surface roughness of conventional, resin modified and nano-ionomer cements was evaluated after different polishing regimens. Totally 20 specimens of 12 mm thick and 10 mm diameter were prepared using Teflon mold. Prepared specimens were subjected to polishing (n = 5) by Sof-Lex discs, diamond finishing points and 30-fluted carbide burs. Control specimens did not receive any polishing treatment, but mylar trip was used as matrix. Average surface roughness (Ra) in micrometers was measured using Surtronic 3 + profilometer. Results were analyzed using Kruskal-Wallis and Mann-Whitney test. Results: Control specimens (mylar strip) showed least Ra values followed by Sof-Lex disc, carbide finishing burs and diamond finishing points with all types of glass ionomer cements used in the study. Among the GIs tested, Nano-ionomer showed least Ra followed by resin-modified GI and conventional GI. Conclusion: Mylar strip produced the smoothest surface on all the GIs tested. Nano-Ionomer showed the best polish ability with least Ra values.Clinical Relevance to Interdisciplinary DentistryGlass ionomer cements (GIC) is one of the most commonly used direct restorative material used in non-stress bearing areas especially to restore cervical lesion at tooth gingival interfacePolished GIC surface reduces plaque accumulation and thus decreases the incidence of gingival inflammation and thereby prevents periodontal problemsFinishing and polishing of the GIC enhances the longevity and color stability of the restoration.

Comparative Evaluation of Fracture Resistance of Structurally Compromised Canals Restored with Different Dowel Methods

The objective of this in vitro study was to evaluate and compare the fracture resistance and fracture mode of endodontically treated teeth with wide root canals restored with various dowel methods. Fifty human uniradicular mandibular premolar teeth were decoronated and endodontically treated. The canals were widened with diamond points. The specimens were divided into five groups on the basis of type of dowel method used: conventional custom-made cast metal dowel; single glass fiber-reinforced resin dowel; glass fiber-reinforced resin dowel with accessory fiber dowels; relined glass fiber-reinforced resin dowel; and dowels formed with the help of polyethylene fiber ribbon-reinforced resin composite. Specimens were restored with indirect composite crowns, and 150,000 cycles of cyclic loading were applied. The specimens were loaded to test the fracture resistance and fracture mode (repairable and nonrepairable). The cast metal dowel groups had the highest fracture resistance but showed nonrepairable fracture in 90% of specimens. Cast metal dowels had the highest fracture resistance but led to nonrepairable fracture while restoring the wide root canals under cyclic loading. Specimens restored with fiber dowels, accessory dowels, relined dowels, and ribbon-reinforced resin provided adequate fracture resistance with increased incidence of repairable fractures.

A comparative evaluation of dentin caries removal with polymer bur and conventional burs—An &amp;lt;i&amp;gt;in vitro&amp;lt;/i&amp;gt; study

Aim: To evaluate the comparative efficacy of Polymer bur (Smartprep) and Conventional burs (Carbide bur & Diamond Points) in selective Dentin caries removal. Materials and method: 15 freshly extracted carious human premolars and molars were selected for this study. These teeth were split in the center of carious lesion, in order to obtain two corresponding half. Thus 30 samples were prepared in this way. These were randomly divided in to 3 groups of 10 samples each. Group 1: The carious portion of these samples was excavated with the help of polymer bur Smartprep (SS White). Group 3: Prepared with Tungsten carbide round bur (No. 018). Group 3: Prepared with the help of Diamond points (No. 018). The period of time involved in this process is measured. After excavation of all carious lesions, a longitudinal section from mid most part of lesion was obtain with the help of diamond disc at slow speed. After staining with caries detector dye “Seek”, the sections were subjected to histological evaluation under stereomicro-scope. The thickness of remaining caries is measured in more or less than 1 mm. Results: The difference in grading of remaining carious dentin between Polymer bur and Conventional burs were statistically non- significant, but Polymer bur taken more time in comparison to Conventional burs. Conclusion: Smartprep bur is more conservative in selectively dentin caries removal than Conventional burs but same time it is more time consuming than Conventional burs.

Grinding performance and workpiece integrity when superabrasive edge routing carbon fibre reinforced plastic (CFRP) composites

Data is presented for wheel wear, cutting forces and workpiece integrity when high speed routing 10mm thick CFRP laminates using single layer electroplated diamond and CBN grinding points as opposed to standard end milling tools. A 60,000rpm retrofit spindle was utilised to accommodate the 10mm diameter wheels having grit sizes of 76, 151 and 252μm employed under either roughing or finishing parameters. Wear of CBN points exhibited a near two-fold increase over diamond with a similar ratio for cutting forces. Despite use of flood cooling, point geometry when roughing compromised life and integrity due to excessive clogging.

The grinding efficiency by diamond points developed for yttria partially stabilized zirconia

Recently, the use of all-ceramic restorations has increased and been applied for many types of clinical treatment such as bridges which can be made with high strength ceramic material: yttria partially stabilized zirconia (Y-PSZ) employing the CAD/CAM system. Consequently, points that can grind high strength ceramic material effectively are necessary for modifying the shape of restorations or removing them. So in our research, we fabricated new diamond points used to grind Y-PSZ. These points were made by electrodeposition of diamond grains. The diameter of the diamond grains are larger (200 µm) than that of traditional points (100 µm). High strength ceramic material was ground to assess the grinding weight and grinding depth various types of points. As a result, Y-PSZ could be ground efficiently with the diamond point which has a larger diameter and employs lager grains (200 µm).