• Journal of Periodontal and Implant Science
• /
• v.23 no.3
• /
• pp.461-474
• /
• 1993

This study was performed to estimate the effect of plaque control on the progress of the repair pattern of the alveolar bone surface after bone surgery. In this experiment six mongrel dogs were used, four of them were as experimental group and others were as control. In the case of experimental group, dental floss ligature was tied over the neck of crown for permiting of plaque accumulation during one week before surgery and oral hygiene procedures were not performed. In control group, all the surgical intervention was done as same procedure with experimental except oral hygiene program. After surgery plaque was controlled during one week with using the chlorhexidine brushing. Animals were sacrificed at 1,2,4,6 weeks after osseous surgery. The results were as follows : 1. The alveolar bone defects were covered with regenerated epithelium at one week, matrix change of granulation tissue on subcutaneous area was observed, and new bone formation was initiated from the surface of the bone defects. 2. The connective tissue arrangement revealed more dense, new bone formation by osteoblasts was active at 2 weeks and proliferation of gingival epithelium and alveolar bone tissue were evident at 4 weeks, and almostly recovered to normal condition at 6 weeks. 3. In experimental group, inflammatory reaction was persistent in early stage and bone repair was delayed compared to control group. 4. In control group, matrix change of granulation tissue was initiated from one week, regeneration of gingival epithelium and maturation of subcutaneous conective tissue and new bone formation were evident at 2 weeks, so almost normal bone regeneration was observed at 4,6 weeks.

• Journal of Periodontal and Implant Science
• /
• v.38 no.1
• /
• pp.67-74
• /
• 2008

Purpose: The aim of this study was to evaluate the effect of Er:YAG laser on microstructure and roughness of $TiO_2$ blasting implant surface. Materials and Methods: Ten $TiO_2$ blasting implant were used in this experiment. One implant was control group, and nine $TiO_2$ blasting implant surfaces were irradiated with Er:YAG laser under 100 mJ/pulse, 140 mJ/pulse, and 180 mJ/pulse condition for 1 min, 1.5 min, and 2 min respectively. Optical interferometer and scanning electron microscopy was utilized to measure roughness and microstructure of specimens. Results: The surface roughness was decreased after Er:YAG laser irradiation in all groups, but there was no significant difference. 100 mJ/pulse and 140 mJ/pulse group did not alter the $TiO_2$ blasting implant surface in SEM study while 180 mJ/pulse group altered the $TiO_2$ blasting implant surface. Implant surfaces showed melting, microfracture and smooth surface in 180 mJ/pulse group. Conclusion: Detoxification of implant surface using Er:YAG laser must be irradiated with proper energy output and irradiation time to prevent implant surface alteration.

• The Journal of the Korean dental association
• /
• v.55 no.11
• /
• pp.789-799
• /
• 2017

Ultrasound images are noninvasive, can be observed in real time, have no radiation exposure, do not cause pain, and are not restricted in use depending on the patient's prosthetic implant or medical condition. Since the use of ultrasound in the dental field was first applied for tooth preparation in 1957, the use of diagnostic ultrasound for the first time in 1963 has been reported. Currently, it is used in the diagnosis of soft tissue lesions such as malignant tumor or salivary gland disease, fine needle aspiration test, temporomandibular joint disease, lymph node metastasis, measurement of muscle thickness and inflammatory diseases, differentiation of periapical cyst and granulation tissue, measurement of periodontal tissue thickness. The ultrasound image can be visualized in real time. The clinician can explain the structure to the patient while consulting the patient and consult the patient. When injecting the drug into a specific site or aspirating a specific site or substance, So that it can be confirmed and practiced. Recently, ultrasonic equipment specialized in the dental field has been developed and marketed, and it is expected that the use of ultrasonic waves will become active in the dentistry. In the future, development of popular equipment with size and frequency suitable for dental diagnosis and various researches on maxillofacial ultrasonic anatomy. If clinical studies are continuously carried out to demonstrate efficacy, ultrasound is expected to aid in accurate diagnosis and treatment throughout the dentistry.

• Journal of Periodontal and Implant Science
• /
• v.38 no.3
• /
• pp.543-550
• /
• 2008

Purpose: The purpose of this study was to investigate induction of cytokine expression in human gingival fibroblasts (HGFs) by whole cell and the components of T. forsythia. Material and Methods: After HGFs were treated with lipopolysaccharide (LPS), membrane protein isolated from T. forsythia or culture media of T. forsythia, the induction of interleukin (IL)-1, IL-6 and IL-8 was examined with real-time PCR and ELISA. Their induction ability of cytokines was compared with whole bacteria. Result: The expression of IL-6 and IL-8 was significantly induced in HGFs by whole bacteria and membrane protein. The expression of IL-$1{\beta}$ was induced by membrane protein of T. forsythia, not by whole bacteria. LPS and condition media of T. forsythia slightly activated HGFs. Conclusion: The membrane protein of T. forsythia could be one of virulence factors.

• Journal of Periodontal and Implant Science
• /
• v.31 no.2
• /
• pp.357-369
• /
• 2001

In this present study, the healing process and the recurrence of pigmentation were evaluated clinically and histologically in accordance with the extent and the range of pigmentation after phenol was applied to remove melanin pigmentation in gingiva. Six mongrel dogs were used. The melanin pigmentation in canine gingiva were classified into slight, moderate and severe according to the extent of pigmentation and divided into local and diffuse types according to the range. Following general and local anesthesia, 90% phenol was applied to the pigmented gingiva of the subjects with small cotton balls until the surface was etched to be whitish and was neutralized with small cotton balls soaked by 95% alcohol. The contralateral pigmented gingiva to the one treated with phenol, was treated by surgical deepithelialization. At 1, 3 and 8 weeks, the treated gingiva was examined clinically and evaluated histologically following H-E stain, and HMB 45 stain for melanocyte after biopsy. In the phenol treated sites, epithelium and connective tissue healed normally and there was no pigmentation at 1 week. At 3 weeks of healing, melanin repigmentation was observed in the severe local type and moderate to severe diffuse type. In the surgically deepithelialized sites, healing was delayed, compared to phenol treated sites and the infiltration of the inflammatory cells and congestion in connective tissue was shown at 1 week. At 3 weeks, healing was completed and there was a partial melanin repigmentation. At 8 weeks of healing, the extent and the range of repigmentation were increased in both group according to the extent or range priot to depigmentation procedure. These results suggpriorest that the removal of melanin pigmentation with 90% phenol application result in normal healing process of gingiva. However, in the severe local type and moderate to severe diffuse type, sites treated with phenol showed repigmentation at 3 week, which was earlier than surgical deepithelialized sites. Therefore it is required to select appropriate method according to initial condition of pigmentation.

• The Journal of the Korean dental association
• /
• v.57 no.9
• /
• pp.514-522
• /
• 2019

In accordance with Article 33(8) of the Korean Medical Law, it is stated that a medical person cannot open or operate a medical institution by borrowing the name of another medical person. However, the publicity of medical care is threatened by the recent illegal network dental clinics. The purpose of this study is to investigate the actual condition of illegal network dentistry and to analyze the cases and to find out the reason why the prohibition of double opening & operating of medical institution. As a result, the illegal network dental clinics treated less health care insurance treatment such as dental caries and periodontal treatment than general dental hospitals. In contrast, the rate of implementation of illegal network dentistry was high in endodontics treatment and extraction, which could lead to uninsured treatments such as crowns and implants. As a result of Supreme Court precedent analysis, it is concluded that illegal act is not only the opening of a medical institution by borrowing the name of other medical personnel, but also the duplicated operation which has the authority to make decision about management matters of medical institutions. The results of the patient's case survey also showed that excessive dental treatment due to such as dental staff incentive system. In conclusion, the illegal network dental clinics not only threatens the oral health of the public, but also causes leakage of health insurance premiums. In other words, the ban on opening and operating the multiple medical institution should be strictly applied as a strong protection device for protecting the patient in dental case.

• Journal of Industrial Convergence
• /
• v.21 no.2
• /
• pp.73-77
• /
• 2023

This study investigated the level of knowledge about changes in the oral environment according to the presence or absence of smoking in adults in their 20s and 40s. It was conducted to use as basic data for the relationship between periodontal disease and smoking and the importance of concurrent education on smoking cessation during oral health education for adults.In subjective oral condition analysis, 65.4% of non-smokers and 59.0% of smokers thought that it was very good or good. Also, in both the non-smokers and smokers groups, the most common answer was that they thought the cleanliness of non-smokers would be higher. To the question of whether they had ever received anti-smoking education, 63.9% of non-smokers and 76.1% of smokers answered 'yes'. In the education that 'the oral environment changes depending on whether or not there is smoking', the non-smoker group showed 'no' and the smoker group showed 'yes' respectively. As a result, oral health education related to smoking and prevention It is thought that specific and active educational methods should be accompanied for this.

• Journal of Periodontal and Implant Science
• /
• v.53 no.1
• /
• pp.85-95
• /
• 2023

Purpose: In recent years, guided implant surgery has been widely used for the convenience of patients and surgeons. Further streamlining the surgical procedure would make implant surgery more convenient. Low-speed water-free conditions are often used in guided implant surgery. Therefore, in this study, we attempted to confirm once again whether drilling was safe at a low speed without water. The main purpose of this study was to evaluate whether a simplified drilling protocol that omits some intermediate steps in the drilling process was safe from the viewpoint of heat generation. Methods: D1 density artificial bone blocks were drilled under 50 rpm, 10 N·cm water-free conditions, and the surface temperature was measured using a digital infrared camera. First, drilling was performed with the sequential drilling method, which is the most widely used technique. Second, for each drill diameter, the temperature change was measured while performing simplified drilling with omission of the previous 1, 2, or 3 steps. Results: In sequential drilling, the heat generated during drilling at all diameters was less than the critical temperature of osteonecrosis (47℃) except for the ⌀2 drill. Statistical significance was observed in all groups when comparing sequential and simplified drilling in the ⌀3.2, ⌀3.8, and ⌀4.3 drills (P<0.001). However, in the simplified drilling procedures, the temperature was below the osteonecrosis threshold temperature (47℃) except for the ⌀4.3 drill with the omission of the previous 3 steps (⌀3.0, ⌀3.2, and ⌀3.8). Conclusions: In general, drilling under low-speed, water-free conditions has shown stable results in terms of heat generation. Simplified drilling showed statistically significantly greater heat generation than sequential drilling. However, most of the diameters and omitted steps seem to be clinically acceptable, so it will be useful if an appropriate selection is made according to the patient's clinical condition.

• Journal of Periodontal and Implant Science
• /
• v.54 no.2
• /
• pp.65-74
• /
• 2024

Purpose: This longitudinal cohort study aimed to evaluate the relationship between osteonecrosis of the jaw and pulp and periapical disease in patients who were administered bisphosphonates. Methods: Using data from a nationwide cohort, we examined the association among dental caries, pulp and periapical disease, and osteonecrosis of the jaw in women aged >50 years who received bisphosphonates for more than 1 year between 2002 and 2015. Because of ambiguities in the diagnosis of osteonecrosis of the jaw in population-based data, we operationally defined and categorized the condition into established and potential osteonecrosis of the jaw. Results: Pulp and periapical disease significantly increased the development of both established and potential osteonecrosis of the jaw (hazard ratio, 2.21; 95% confidence interval, 1.40-3.48; and hazard ratio, 2.22; 95% confidence interval, 1.65-2.98, respectively). Root canal treatment did not have any influence on the development of osteonecrosis of the jaw. Conclusions: Pulp and periapical disease may be a major risk factor for osteonecrosis of the jaw. The study findings suggest that patients should undergo regular dental examinations to detect pulp and periapical disease before or during the administration of bisphosphonates and that root canal treatment should be considered to decrease the risk of osteonecrosis of the jaw.

• Journal of Periodontal and Implant Science
• /
• v.53 no.5
• /
• pp.376-387
• /
• 2023

Purpose: Peri-implantitis (PI) is an inflammatory condition associated with the destruction of bone tissue around a dental implant, and diode lasers can be used to treat this disease. In this study, we aimed to evaluate the effectiveness of a 940-nm diode laser for the nonsurgical treatment of PI. Methods: Twenty patients (8 women and 12 men) were enrolled in a split-mouth randomized controlled study. In the control group (CG), mechanical debridement with titanium curettes accompanied by airflow was performed around the implants. The test group (TG) was treated similarly, but with the use of a diode laser. Clinical measurements (plaque index, gingival index [GI], probing pocket depth [PPD], bleeding on probing [BOP], clinical attachment level, and interleukin-1β [IL-1β] in the peri-implant crevicular fluid) were evaluated and recorded at baseline and 3 months. IL-1β levels were determined using the enzyme-linked immunosorbent assay method. Results: The symptoms were alleviated in both groups at 3 months as assessed through clinical measurements. GI, BOP, and PPD were significantly lower in the TG than in the CG (P<0.05). The IL-1β level increased post-treatment in both groups, but this increase was only statistically significant (P<0.05) in the CG. Conclusions: The diode laser enabled improvements in clinical parameters in the periimplant tissue. However, it did not reduce IL-1β levels after treatment. Further studies about the use of diode lasers in the treatment of PI will be necessary to evaluate the effects of diode lasers in PI treatment.