• The korean journal of orthodontics
• /
• v.53 no.5
• /
• pp.307-316
• /
• 2023

Objective: To evaluate the effects of an electric toothbrush with vibrational frequencies of 125 Hz and 150 Hz on the orthodontic tooth movement (OTM) rate and the production of prostaglandin E2 (PGE2). Methods: Out of thirty patients (aged 18-25 years; 16 females and 14 males), ten patients each formed Group A and B, who used electric toothbrushes with 125 Hz and 150 Hz vibrations, respectively. The remaining ten patients (Group C) served as the control group and did not use electric toothbrushes. The rate of OTM and levels of PGE2 using microcapillary pipettes were calculated before the start of retraction (T0), on the 30th day (T1), on the 60th day (T2), and on the 90th day (T3) from the start of retraction in all the groups. Results: There was a statistically significant difference in the mean OTM values and PGE2 levels in all three groups at different time intervals, with the maximum difference seen in Group B compared to Group A and least in Group C at T1, T2 and T3. Conclusions: The rate of OTM and levels of PGE2 were highest in patients who used an electric toothbrush with 150 Hz mechanical vibration compared to those who used an electric toothbrush with 125 Hz mechanical vibration and least in patients who did not use an electric toothbrush. Mechanical vibration led to an increase in the PGE2 levels and accelerated the OTM.

• The korean journal of orthodontics
• /
• v.43 no.6
• /
• pp.302-310
• /
• 2013

Orthodontic closure of old, edentulous spaces in the mandibular posterior region is a major challenge. In this report, we describe a method of orthodontic closure of edentulous spaces in the mandibular posterior region accelerated by piezoelectric decortication and alveolar ridge expansion. Combined piezosurgical and orthodontic treatments were used to close 14- and 15-mm-wide spaces in the mandibular left and right posterior areas, respectively, of a female patient, aged 18 years and 9 months, diagnosed with skeletal Class III malocclusion, hypodontia, and polydiastemas. After the piezoelectric decortication, segmental and full-arch mechanics were applied in the orthodontic phase. Despite some extent of root resorption and anchorage loss, the edentulous spaces were closed, and adequate function and esthetics were regained without further restorative treatment. Alveolar ridge expansion-assisted orthodontic space closure seems to be an effective and relatively less-invasive treatment alternative for edentulous spaces in the mandibular posterior region.

• Natural Product Sciences
• /
• v.11 no.1
• /
• pp.45-49
• /
• 2005

Previously, a flavonoid fraction, which consisted mainly of protocatechuic acid, fustin, fisetin, sulfuretin, and butein, here named RCMF [${\underline{R}}hus$ verniciflua Stokes (RVS) ${\underline{c}}hloroform-{\underline{m}}ethanol\;{\underline{f}}raction$], was prepared from a crude acetone extract of RVS which is traditionally used as a food additive and as an herbal medicine. In the present study, we investigated the effects of $TNF-{\alpha}$ on RCMF-induced growth inhibition and apoptosis induction using human osteosarcoma (HOS) cells. The results from tritium uptake and MTT assays showed that $TNF-{\alpha}$ treatment itself (10 ng/ml) did not induce any cytotoxicity, but it actively accelerated RCMF-mediated cytotoxicity of HOS cells. RCMF-induced cytotoxicity and its facilitation by $TNF-{\alpha}$ was verified to be apoptotic, based on the increased DNA fragmentation and low fluorescence intensity in nuclei after propidium iodide (PI) staining of HOS cells. This speculation was further demonstrated by monitoring the Annexin V/PI double staining which could discriminate the difference between apoptotic and necrotic deaths. Collectively, our findings indicate that $TNF-{\alpha}$ accelerates RCMF-induced cytotoxicity in HOS cells.

• The korean journal of orthodontics
• /
• v.48 no.3
• /
• pp.200-211
• /
• 2018

The aim of this systematic review was to evaluate the effectiveness and complications of corticotomy and piezocision in canine retraction. Five electronic databases (PubMed, SCOPUS, Web of Science, Embase, and CENTRAL) were searched for articles published up to July 2017. The databases were searched for randomized control trials (RCTs), with a split-mouth design, using either corticotomy or piezocision. The primary outcome reported for canine retraction was either the amount of tooth movement, rate of tooth movement, or treatment time. The secondary outcome was complications. The selection process was based on the PRISMA guidelines. A risk of bias assessment was also performed. Our search retrieved 530 abstracts. However, only five RCTs were finally included. Corticotomy showed a more significant (i.e., 2 to 4 times faster) increase in the rate of tooth movement than did the conventional method. For piezocision, both accumulative tooth movement and rate of tooth movement were twice faster than those of the conventional method. Corticotomy (with a flap design avoiding marginal bone incision) or flapless piezocision procedures were not detrimental to periodontal health. Nevertheless, piezocision resulted in higher levels of patient satisfaction. The main limitation of this study was the limited number of primary research publications on both techniques. For canine retraction into the immediate premolar extraction site, the rate of canine movement after piezocision was almost comparable to that of corticotomy with only buccal flap elevation.

• Journal of Periodontal and Implant Science
• /
• v.53 no.1
• /
• pp.2-19
• /
• 2023

Purpose: Surgical techniques in orthodontics have received widespread attention in recent years. Meanwhile, biomaterials with high molecular content have been introduced, such as platelet concentrates (PCs), which may accelerate orthodontic tooth movement (OTM) and reduce periodontal damage. The present systematic review aimed to answer the following PICO question: "In patients in whom orthodontic surgical techniques are performed (P), what is the effectiveness of using PCs over the surgical site (I) when compared to not placing PCs (C) to achieve faster tooth movement (O)?" Methods: A search was performed in 6 databases. The criteria employed were those described in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses declaration. The present review included studies with a control group that provided information about the influence of PCs on the rate of OTM. Results: The electronic search identified 10 studies that met the established criteria. Conclusions: The included studies were very diverse, making it difficult to draw convincing conclusions. However, a tendency was observed for OTM to be accelerated when PCs were used as an adjuvant for canine distalization after premolar extraction when distalization was started in the same session. Likewise, studies seem to indicate an association between PC injection and the amount of canine retraction. However, it is not possible to affirm that the use of PCs in corticotomy shortens the overall treatment time, as this question has not been studied adequately.

• The korean journal of orthodontics
• /
• v.49 no.6
• /
• pp.372-380
• /
• 2019

Objective: To determine the effects of a local injection of leukocyte-platelet-rich plasma (L-PRP) on orthodontic tooth movement in rabbits. Methods: Twenty-three male New Zealand white rabbits were included in a split-mouth design. Tooth movement with a 100-g nickel-titanium closed-coil spring was performed on the maxillary first premolars. L-PRP was injected submucosally at the buccal and lingual areas of the first premolar in one random side of the maxilla and the other side served as the control and received normal saline. The amount of tooth movement was assessed on three-dimensional digital models on days 0, 3, 7, 14, 21, and 28. Histological findings and osteoclast numbers were examined on day 0 as the baseline and on days 7, 14, and 28. Results: The L-PRP group showed significantly greater cumulative tooth movement at all observed periods. However, a significantly higher rate of tooth movement was observed only on days 0-7 and 7-14. The osteoclast numbers were significantly increased in the L-PRP group on days 7 and 14. Conclusions: Local injection of L-PRP resulted in a transient increase in the rate of tooth movement and higher osteoclast numbers.

• The korean journal of orthodontics
• /
• v.42 no.4
• /
• pp.207-217
• /
• 2012

Objective: This study aimed to evaluate the effect of an intentionally created socket on bone remodeling with orthodontic tooth movement in rabbits. Methods: Eighteen male rabbits weighing 3.8 - 4.25 kg were used. An 8-mm deep and 2-mm wide socket was drilled in the bone 1 mm mesial to the right mandibular first premolar. The left first premolar was extracted to serve as an extraction socket. A traction force of 100 cN was applied to the right first premolar and left second premolar. Sections were obtained at the middle third of the moving tooth for both the drilled and extraction sockets and evaluated with hematoxylin and eosin staining and immunohistochemical analyses. The amount of tooth movement and tartrate-resistant acid phosphatase (TRAP)-positive cell count were compared between the 2 groups using the Mann-Whitney U test. Results: At week 2, the distance of tooth movement was significantly higher in the intentional socket group (p < 0.05) than in the extraction socket group. The number of TRAP-positive cells decreased in week 2 but increased in week 3 (p < 0.05). However, there were no significant differences between the groups. Furthermore, results of transforming growth factor (TGF)-${\beta}$ staining revealed no significant differences. Conclusions: The intentional socket group showed greater distance of tooth movement than did the extraction socket group at week 2. Osteoclast counts and results of immunohistochemical analyses suggested elevated bone remodeling in both the groups. Thus, osteotomy may be an effective modality for enhancing tooth movement in orthodontic treatment.

• The korean journal of orthodontics
• /
• v.50 no.3
• /
• pp.157-169
• /
• 2020

Objective: The aim of this retrospective study was to evaluate the pre- and postsurgical bone densities at alveolar and extra-alveolar sites following two-jaw orthognathic surgery. Methods: The sample consisted of 10 patients (mean age, 23.2 years; range, 18.0-27.8 years; 8 males, 2 females) who underwent two-jaw orthognathic surgery. A three-dimensional imaging program (Invivo 5) was used with multidetector computed tomography images taken pre- and postoperatively (obtained 32.3 ± 6.0 days before surgery and 5.8 ± 2.6 days after surgery, respectively) for the measurement of bone densities at the following sites: (1) alveolar bone in the maxilla and mandible, (2) extra-alveolar sites, such as the top of the head, menton (Me), condyle, and the fourth cervical vertebrae (C4). Results: When pre- and postsurgical bone densities were compared, an overall tendency of decrease in bone density was noted. Statistically significant reductions were observed in the densities of cancellous bone at several areas of the maxillary alveolar bone; cortical and cancellous bone in most areas of the mandibular alveolar bone; cortical bone in Me; and cancellous bone in C4. There was no statistically significant difference in bone density in relation to the depth of the alveolar bone. In a comparison of the bone densities between groups with and without genioplasty, there was almost no statistically significant difference. Conclusions: Accelerated tooth movement following orthognathic surgery may be confirmed with reduced bone density. In addition, this study could offer insights into bone metabolism changes following orthognathic surgery, providing direction for further investigations in this field.

• The korean journal of orthodontics
• /
• v.47 no.2
• /
• pp.130-141
• /
• 2017

The aim of this case report was to describe an innovative orthodontic treatment method that combined surgical and orthodontic techniques. The novel method was used to achieve a positive result in a case of moderate crowding by employing a computer-guided piezocision procedure followed by the use of clear aligners. A 23-year-old woman had a malocclusion with moderate crowding. Her periodontal indices, oral health-related quality of life (OHRQoL), and treatment time were evaluated. The treatment included interproximal corticotomy cuts extending through the entire thickness of the cortical layer, without a full-thickness flap reflection. This was achieved with a three-dimensionally printed surgical guide using computer-aided design and computer-aided manufacturing. Orthodontic force was applied to the teeth immediately after surgery by using clear appliances for better control of tooth movement. The total treatment time was 8 months. The periodontal indices improved after crowding correction, but the oral health impact profile showed a slight deterioration of OHRQoL during the 3 days following surgery. At the 2-year retention follow-up, the stability of treatment was excellent. The reduction in surgical time and patient discomfort, increased periodontal safety and patient acceptability, and accurate control of orthodontic movement without the risk of losing anchorage may encourage the use of this combined technique in appropriate cases.

• The korean journal of orthodontics
• /
• v.40 no.4
• /
• pp.227-238
• /
• 2010

Objective: The purpose of this study was to analyze the effect of growth hormone treatment (GHT) on craniofacial growth in children of short stature. Methods: Nineteen untreated children of short stature were referred from the Pediatric Department, Yeungnam University Hospital as a subject group. All subjects had lateral cephalograms taken before, after 1 year and after 2 years of growth hormone treatment. As a reference group, we selected 19 normal children with paired sampling who matched the subjects' age and sex, from the Department of Orthodontics, Kyungpook National University Hospital. Results: Before GHT, anterior cranial base length and upper posterior facial height, posterior total facial height, mandibular ramus length, and mandibular corpus length were significantly smaller in the reference group. In angular craniofacial measurements, saddle angle and mandibular plane angle were larger. SNA and SNB were smaller in the reference group. After two years of GHT, growth hormone accelerated growth in several craniofacial components. The posterior total facial height, the anterior, posterior cranial base length, and the mandibular ramus length were increased. And the difference in mandibular plane angle and ANB values compared with the reference group was decreased. Conclusions: GHT over 2 years leads to a craniofacial catch-up growth tendency, which is pronounced in interstitial cartilage and condylar cartilage.