• Journal of Periodontal and Implant Science
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• v.29 no.1
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• pp.65-80
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• 1999

The purpose of this study was to evaluate the effects of periodontal curet and various rotating instruments on the root surfaces. Thirty-five extracted teeth with advanced periodontal disease were used. They was root planed with periodontal curet, periodontal Perio-Clean bur, periodontal Roto-Perio bur, resin polishing ET bur, and resin polishing diamond fissure bur. To find dentinal tubule orifices on the root surface, tetracycline HCI solution was applied to the one tooth of treated each group. Then, root surfaces were investigated using scanning electron microscope. Amount of loss of cementum was evaluated by loss of tooth substance index. The results were as follows. 1. Groups treated with periodontal curet and Perio-Clean bur showed irregular surface and concavities. Concavities seemed to be lacunae of cementocyte. Other groups treated with Roto-Perio bur, resin polishing ET bur, and resin polishing diamond fissure bur showed partially opened dentinal tubule orifice. 2. Groups treated with periodontal curet and Perio-Clean bur and tetracycline HCl showed irregular surface. No dentinal tubule orifice was seen. Other groups treated with Roto-Perio bur, resin polishing ET bur, and resin polishing diamond fissure bur and tetracycline HCl showed dentinal tubule orifice with various shape and size. 3. Loss of tooth substance indices were compared between groups. There was no statistically difference between periodontal curet and Perio-Clean bur groups. There were statistically differences between periodontal curet and Roto-Perio bur, ET bur, and diamond fissure bur groups. As a result of this study, groups treated with Roto-Perio bur, resin polishing ET bur, and resin polishing diamond fissure bur showed more cementum removed than groups treated with periodontal curet and Perio-Clean bur. Therefore, in a conventional treatment for periodontal disease, it was recommended that periodontal curet or Perio-Clean bur should be used. In a treatment for regeneration of periodontal tissue, it was recommended that Roto-Perio bur, resin polishing ET bur, or resin polishing diamond fissure bur should be used

• The Journal of Advanced Prosthodontics
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• v.11 no.1
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• pp.41-47
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• 2019

PURPOSE. Surface finishing of a zirconia restoration is essential after clinical adjustment. Herein, we investigated the effects of a surface finishing protocol for monolithic zirconia on final roughness and bacterial adherence. MATERIALS AND METHODS. Forty-eight disk-shaped monolithic zirconia specimens were fabricated and divided into four groups (n = 12) based on initial surface treatment, finishing, and polishing protocols: diamond bur+polishing bur (DP group), diamond bur+stone grinding bur+polishing bur (DSP group), no diamond bur+polishing bur (NP group), and no diamond bur+stone grinding bur+polishing bur (NSP group). Initial and final surface roughness was measured with a profilometer, and shown using scanning electron microscope. Bacterial adhesion was evaluated by quantifying Streptococcus mutans in the biofilm. Kruskal-Wallis and Mann-Whitney U tests were used to compare results among groups, and two-way analysis of variance was used to evaluate the effects of grinding burs on final roughness (${\alpha}=.05$). RESULTS. The DP group had the highest final Ra value, followed by the DSP, NP, and NSP groups. Use of the stone grinding bur as a coarse-finishing step significantly decreased final Ra values when a diamond bur was used (P<.001). Omission of the stone grinding bur increased biofilm formation on specimen surfaces. Combining a stone grinding bur with silicone polishing burs produced the smallest final biofilm values, regardless of the use of a diamond bur in initial surface treatment. CONCLUSION. Coarse finishing of monolithic zirconia with a stone grinding bur significantly decreased final Ra values and bacterial biofilm formation when surfaces had been roughened by a diamond bur.

• Restorative Dentistry and Endodontics
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• v.36 no.6
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• pp.477-482
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• 2011

Objectives: The purpose of this study was to compare the microshear bond strength (uSBS) to enamel prepared with different burs and to determine what type of bur were chosen when a self-etching primer adhesive was used. Materials and Methods: Enamel of forty-two human molars were used. They were divided into one of six groups (n = 7), Group 1, coarse (125 - 150 ${\mu}m$) diamond bur; Group 2, standard (106 - 125 ${\mu}m$) diamond bur; Group 3, fine (53 - 63 ${\mu}m$) diamond bur; Group 4, extrafine (20 - 30 ${\mu}m$) diamond bur; Group 5, plaincut carbide bur (no. 245); Group 6, cross-cut carbide bur (no. 557). Clearfil SE Bond and Clearfil AP-X (Kuraray Medical Inc.) was bonded to enamel surface. The bonded specimens were subjected to uSBS testing. Results: The uSBS of Group 4 was the highest among groups and it was significantly higher than that of Groups 1, 2, 3, and 6 (p < 0.05), but it was not significantly different from that of Group 5. Conclusions: Different burs used on enamel surface affected the microshear bond strengths of a self-etching primer adhesive to the enamel surface. In the case of Clearfil SE Bond, extrafine diamond and plain-cut carbide bur are recommended for bonding to enamel.

• The Journal of Advanced Prosthodontics
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• v.11 no.1
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• pp.1-6
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• 2019

PURPOSE. The purpose of this in vitro study was to evaluate the effect of surface grinding and polishing procedures using high speed zirconia diamond burs with different grit sizes on the phase transformation and flexural strength of zirconia. MATERIALS AND METHODS. Forty disc shape specimens ($15{\times}1.25mm$) with a cylindrical projection in the center of each disc ($1{\times}3mm$) were fabricated with 3Y-TZP (Prettau, Zirkonzahn, Italy). The specimens were divided into 4 groups (n=10) according to the grinding and polishing procedures: Control group - grinding (coarse-grit diamond bur), Group 1 - grinding (coarse-grit diamond bur) + polishing, Group 2 - grinding (fine-grit diamond bur) + polishing, and Group 3 - grinding (fine grit diamond bur). Each specimen was analyzed by 3D-OM, XRD analysis, and biaxial flexural strength test. RESULTS. Based on the surface morphology by 3D-OM images, polished specimens showed smoother surface and lower roughness value (Ra). In the result of XRD analysis, partial phase transformation from tetragonal to monoclinic zirconia occurred in all groups. Control group, ground with a coarse grit diamond bur, showed more $t{\rightarrow}m$ phase transformation and lower flexural strength than Groups 1 and 2 significantly. CONCLUSION. The flexural strength in all specimens after grinding and polishing showed over 500 MPa, and those were clinically acceptable. However, grinding with a coarse grit diamond bur without polishing induced the phase transformation and low strength. Therefore, surface polishing is required for the occlusal adjustment using a high speed zirconia diamond bur to reduce the phase transformation and to prevent the decrease of flexural strength of zirconia.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.4 s.97
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• pp.148-154
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• 1999

This study was carried out to verify grinding performance of dental diamond bur and investigate the possibility of AE application in dentistry field. Workpieces were made of acryl and bovine respectively for the experiments in this study. Grinding test was conducted to get the data of grinding resistance and specific grinding energy of four different types of diamond bur by using tool dynamometer. AE signal was acquired to verify grinding process in the AE measuring system. Tool wear was observed to find parameters about grinding characteristics of diamond bur by means of SEM picture. It was found that the wear of dental diamond bur could be detected with polishing of grinding material, removal of adhesive parts, wear of particles neighboring cutting nose, loss of material and elevation of temperature. The wear of B, C, D type diamond bur is due to wear and fracture of grain size. Abnormal state can be found through the behavior of AE signal in the grinding working. As a result, it is expected that forecast of abnormal state is possible using AE equipments under real time process.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.3
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• pp.76-82
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• 1999

This study was carried out to verify finding performance of dental diamond bur and investigate the possibility of AE application in density field. Work pieces were made of acryl and bovine respectively for the experiments in this study. Grinding test was conducted to get the data of grinding resistance and specific finding energy of low different types of diamond bur by using tool dynamometer. AE signal was acquired to verify grinding process in the AE measuring system. AErms value was increased as the grinding velocity and depth were increasing, but it decreased as the feed rate was increasing. The case of the small value of AE signal is due to abnormal grinding in D type diamond bur. By analyzing AErms start and finish time of grinding working, abnormal grinding state can be confined. Abnormal state can be found through the behavior of AE signal in the finding working. As a result, it is expected that forecast of abnormal state is possible using AE equipments under real time process.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.80-84
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• 1996

This paper aims at reviewing the Possibility application over normal or abnormal, detection used by AE and the wear characteristics of grinding process. In this study, when diamond bur in dentistry with chosen grinding conditions were tuned at grinding. The variation of grinding resistance and hE signal is detected by the use of AE measuring system. The tests are carried out in accordance with diamond burs and workpiece; arcyl and bovine. According to the experiment results, the following can be expected; AE has the possibility to detect the state normality and abnormality. However, the grinding resistance measuring can find it difficult to detect it. It can be accurately excerpted from AE occurrence pattern in contact start point of diamond bur and bovine, grinding condition and derailment point. It is known that AE$\_$rms/ is well compatible with grinding resistance. According to the increase of the material removal rate, the specific energy of the diamond bur is inclined to decrease and the grinding resistance has a tendency to increase.

• The Journal of Advanced Prosthodontics
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• v.10 no.2
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• pp.93-100
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• 2018

PURPOSE. The purpose of this study was to determine the changing frequency of a diamond bur after multiple usages on 3 different surfaces. MATERIALS AND METHODS. Human premolar teeth (N = 26), disc shaped direct metal laser sintered CoCr (N = 3) and zirconia specimens (N = 3) were used in this study. Groups named basically as Group T for teeth, Group M for CoCr, and Group Z for zirconia. Round tapered black-band diamond bur was used. The specimens were randomly divided into three groups and placed with a special assembly onto the surveyor. 1, 5, and 10 preparation protocols were performed to the first, second, and third sub-groups, respectively. The subgroups were named according to preparation numbers (1, 5, 10). The mentioned bur of each group was then used at another horizontal preparation on a new tooth sample. The same procedure was used for CoCr and zirconia disc specimens. All of the bur surfaces were evaluated using roughness analysis. Then, horizontal tooth preparation surfaces were examined under both stereomicroscope and SEM. The depth maps of tooth surfaces were also obtained from digital stereomicroscopic images. The results were statistically analyzed using One-Way ANOVA, and the Tukey HSD post-hoc tests (${\alpha}=.05$). RESULTS. All of the groups were significantly different from the control group (P<.001). There was no significant difference between groups Z5 and Z10 (P=.928). Significant differences were found among groups T5, M5, and Z5 (P<.001). CONCLUSION. Diamond burs wear after multiple use and they should be changed after 5 teeth preparations at most. A diamond bur should not be used for teeth preparation after try-in procedures of metal or zirconia substructures.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.117-127
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• 1991

The purpose of this study was to evaluate the effect of surface treatment of fractured metal-ceramic crown on bond strength of porcelain repair resin. The specimens were divided into two groups for metal specimens add five groups for porcelain specimens by surface treatment methods. the metal specimens were treated by 2 methods. : micro-sandblasting with $50{\mu}m$ aluminum oxide and grinding with diamond bur. The porcelain specimens were treated by 5 methods : micro-sandblasting with $50{\mu}m$ aluminum oxide, grinding with diamond bur, etching with porcelain etching agent, combination of micro-sandblasting and etching procedure, and combination of grinding and etching procedure. After surface treatment, each specimen was bonded with composite resin and the bond strength was measured and the surface texture was observed by scanning electromicroscope(SEM). The results were as follows : 1. There was significant difference in shear bond strength between metal specimen and prorcelain specimen. 2. Bood strength of metal specimens treated with diamond bur was higher than that treated with $50{\mu}m$ aluminum oxide sandblasting. 3. Bond strength of porcelain specimen treated with diamond bur was higher than that treated with $50{\mu}m$ aluminum oxide sandblasting and porcelain etching agent. 4. There was no significant difference in shear bond strength between the group treated with diamond bur and combined treatment groups respectively. 5. The large undercuts were observed in group treated with diamond bur by SEM.

• Journal of Periodontal and Implant Science
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• v.46 no.2
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• pp.107-115
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• 2016

Purpose: The aim of this study was to evaluate and compare tooth surface characteristics in extracted human molars after cervical enamel projections (CEPs) were removed with the use of three rotating instruments. Methods: We classified 60 extracted molars due to periodontal lesion with CEPs into grade I, II, or III, according to the Masters and Hoskins' criteria. Each group contained 20 specimens. Three rotating instruments were used to remove the CEPs: a piezoelectric ultrasonic scaler, a periodontal bur, and a diamond bur. Tooth surface characteristics before and after removal of the projections were then evaluated with scanning electron microscopy (SEM). We analyzed the characteristics of the tooth surfaces with respect to roughness and whether the enamel projections had been completely removed. Results: In SEM images, surfaces treated with the diamond bur were smoothest, but this instrument caused considerable harm to tooth structures near the CEPs. The piezoelectric ultrasonic scaler group produced the roughest surface but caused less harm to the tooth structure near the furcation. In general, the surfaces treated with the periodontal bur were smoother than those treated with the ultrasonic scaler, and the periodontal bur did not invade adjacent tooth structures. Conclusions: For removal of grade II CEPs, the most effective instrument was the diamond bur. However, in removing grade III projections, the diamond bur can destroy both adjacent tooth structures and the periodontal apparatus. In such cases, careful use of the periodontal bur may be an appropriate substitute.