Jong Hoon Lee

Prof. Jong Hoon Lee

Institute of Advanced Convergence Technology(IACT), Kyungpook National University, Daegu, Republic of Korea
orcid

Research Focus & Metrics

Academic Career Length

27Years (2000-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 September 2023 in Journal of Functional Biomaterials
Verified
Journal Article
Open access
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SBSoo Kyum Bihn
Soo Kyum Bihn
KeunBaDa SonKeunBaDa Son
KeunBaDa Son
YSYoung-Tak Son
Young-Tak Son
Ram Hari DahalRam Hari Dahal
Ram Hari Dahal
SKShukho Kim
Shukho Kim
Kyu-Bok LeeKyu-Bok Lee
Kyu-Bok Lee
(1) Background: The purpose of this study was to evaluate how a zirconia implant surface treated with laser technology affects the degree of biofilm formation. (2) Methods: Experimental titanium (Ti) disks were produced that were sandblasted with large grit and acid-etched (T), and they were compared with zirconia (ZrO2) discs with a machined (M) surface topography; a hydrophilic surface topography with a femtosecond laser (HF); and a hydrophobic surface topography with a nanosecond laser (HN) (N = 12 per surface group). An in vitro three-species biofilm sample (Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi)) was applied to each disc type, and bacterial adhesion was assessed after 48 and 72 h of incubation using an anaerobic flow chamber model. Statistical significance was determined using the Kruskal–Wallis H test, with Bonferroni correction used for the post-hoc test (α = 0.05). (3) Results: Compared to the T group, the M group exhibited more than twice as many viable bacterial counts in the three-species biofilm samples (p < 0.05). In comparison to the T group, the HF group had significantly higher viable bacterial counts in certain biofilm samples at 48 h (Aa and Pi) and 72 h (Pi) (p < 0.05). The HN group had higher viable bacterial counts in Pi at 48 h (5400 CFU/mL, p < 0.05) than the T group (4500 CFU/mL), while showing significantly lower viable bacterial counts in Pg at both 48 (3010 CFU/mL) and 72 h (3190 CFU/mL) (p < 0.05). (4) Conclusions: The surface treatment method for zirconia discs greatly influences biofilm formation. Notably, hydrophobic surface treatment using a nanosecond laser was particularly effective at inhibiting Pg growth.

26 October 2023 in Bioengineering
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Journal Article
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JLJinseok Lee
Jinseok Lee
KeunBaDa SonKeunBaDa Son
KeunBaDa Son
SHSung-Min Hwang
Sung-Min Hwang
YSYoung-Tak Son
Young-Tak Son
YKYong-Gun Kim
Yong-Gun Kim
JLJae Mok Lee
Jae Mok Lee
The purpose of this study was to investigate the effects of different peri-implantitis treatment methods (Er,Cr:YSGG laser, diode laser, and electrocautery) on various titanium implant surfaces: machined; sandblasted, large-grit, and acid-etched; and femtosecond laser-treated surfaces. Grade 4 titanium (Ti) disks, with a diameter of 10 mm and a thickness of 1 mm, were fabricated and treated using the aforementioned techniques. Subsequently, each treated group of disks underwent different peri-implantitis treatment methods: Er,Cr:YSGG laser (Biolase, Inc., Foothill Ranch, CA, USA), diode laser (Biolase, Inc., Foothill Ranch, CA, USA), and electrocautery (Ellman, Hicksville, NY, USA). Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and wettability were used to characterize the chemical compositions and surfaces of the treated titanium surfaces. Significant changes in surface roughness were observed in both the electrocautery (Sa value of machined surface = 0.469, SLA surface = 1.569, femtosecond laser surface = 1.741, and p = 0.025) and Er,Cr:YSGG laser (Ra value of machined surface = 1.034, SLA surface = 1.380, femtosecond laser surface = 1.437, and p = 0.025) groups. On femtosecond laser-treated titanium implant surfaces, all three treatment methods significantly reduced the surface contact angle (control = 82.2°, diode laser = 74.3°, Er,Cr:YSGG laser = 73.8°, electrocautery = 76.2°, and p = 0.039). Overall, Er,Cr:YSGG laser and electrocautery treatments significantly altered the surface roughness of titanium implant surfaces. As a result of surface composition after different peri-implantitis treatment methods, relative to the diode laser and electrocautery, the Er,Cr:YSGG laser increased oxygen concentration. The most dramatic change was observed after Er:Cr;YSGG laser treatment, urging caution for clinical applications. Changes in surface composition and wettability were observed but were not statistically significant. Further research is needed to understand the biological implications of these peri-implantitis treatment methods.

Verified
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SESeungMo Eun
SeungMo Eun
KeunBaDa SonKeunBaDa Son
KeunBaDa Son
SHSung-Min Hwang
Sung-Min Hwang
YSYoung-Tak Son
Young-Tak Son
YKYong-Gun Kim
Yong-Gun Kim
JLJae Mok Lee
Jae Mok Lee
This study evaluated the effects of various mechanical debridement methods on the surface roughness (Ra) of dental implants, comparing femtosecond laser-treated surfaces with conventionally machined and sandblasted with large-grit sand and acid-etched (SLA) implant surfaces. The fabrication of grade 4 titanium (Ti) disks (10 mm in diameter and 1 mm thick) and the SLA process were carried out by a dental implant manufacturer (DENTIS; Daegu, Republic of Korea). Subsequently, disk surfaces were treated with various methods: machined, SLA, and femtosecond laser. Disks of each surface-treated group were post-treated with mechanical debridement methods: Ti curettes, ultrasonic scaler, and Ti brushes. Scanning electron microscopy, Ra, and wettability were evaluated. Statistical analysis was performed using the Kruskal–Wallis H test, with post-hoc analyses conducted using the Bonferroni correction (α = 0.05). In the control group, no significant difference in Ra was observed between the machined and SLA groups. However, femtosecond laser-treated surfaces exhibited higher Ra than SLA surfaces (p < 0.05). The application of Ti curette or brushing further accentuated the roughness of the femtosecond laser-treated surfaces, whereas scaling reduced the Ra in SLA surfaces. Femtosecond laser-treated implant surfaces, with their unique roughness and compositional attributes, are promising alternatives in dental implant surface treatments.

30 October 2019 in Journal of Welding and Joining
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Journal Article
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SSSeongSeon Shin
SeongSeon Shin
JLJong Hoon Lee
Jong Hoon Lee
SKSungWook Kim
SungWook Kim
JHJunHo Hwang
JunHo Hwang
HKHyun Deok Kim
Hyun Deok Kim

28 February 2023 in Journal of Welding and Joining
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Journal Article
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YKYongjae Kwon
Yongjae Kwon
SSSeongSeon Shin
SeongSeon Shin
SJSangEun Joo
SangEun Joo
JLJong Hoon Lee
Jong Hoon Lee
JHJunHo Hwang
JunHo Hwang
HKHyun Deok Kim
Hyun Deok Kim
In this study, the directed energy deposition (DED) process was applied to additively manufacture cobalt-chromium alloy materials, which are commonly used in molds, dental/orthopedic medical applications, vehicles, and aircraft. The quality of the deposition obtained by using the DED technology is affected by process parameters. Therefore, the aim of this experiment, was to evaluate the microstructure changes caused by varying parameters such as the laser power, laser header moving speed, and powder feeding rate, with the goal of improving and optimizing the stacking quality. The shape, heat-affected zone, and dilution ratio of the microstructure were analyzed using an optical microscope. Furthermore, the global energy density(GED) was calculated because it affects the quality of the 3D-printed product. The optimal process conditions for the DED method determined by calculating the GED under various process conditions.

2 October 2024 in Applied Sciences
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Journal Article
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JPJUNHYEONG PARK
JUNHYEONG PARK
KeunBaDa SonKeunBaDa Son
KeunBaDa Son
YSYoung-Tak Son
Young-Tak Son
YKYong-Gun Kim
Yong-Gun Kim
SHSung-Min Hwang
Sung-Min Hwang
JLJae Mok Lee
Jae Mok Lee
Background: Optical coherence tomography (OCT) is an emerging, radiation-free diagnostic tool in dentistry, providing high-resolution, real-time imaging of both hard and soft tissues, including periodontal areas, for more accurate postoperative evaluations. This study aims to investigate the efficacy of OCT on periodontal tissues in animals by comparing the healing effects of laser therapy with those of conventional surgical instruments. Methods: Six rabbits underwent periodontal surgery using a laser, scalpel, and punch to perform an apically positioned flap on the mandibular anterior incisors and to create a tongue ulcer on the dorsal surface of the tongue. Visual and OCT evaluations were conducted on days 1, 2, 3, 7, and 14. Results: In periodontal surgery, the laser exhibited slightly faster healing compared to other methods. In tongue ulcer formation, the scalpel and punch groups demonstrated slightly faster healing than that of the laser. However, both methods ultimately showed similar healing outcomes. Conclusions: In the dental field, OCT is emerging as a valuable tool for assessing healing, including early stages of healing, in periodontal therapy.