Cementocyte cell death occurs in rat cellular cementum during orthodontic tooth movement

ABSTRACT Objective: To clarify the mechanism of root resorption during orthodontic treatment, we examined cementocyte cell death and root resorption in the cellular cementum on the pressure side during experimental tooth movement. Materials and Methods: Using 8-week-old male Wistar rats, the right first molar was pushed mesiobuccally with a force of 40 g by a Ni-Ti alloy wire while the contralateral first molar was used as a control. Localization and number of cleaved caspase-3-positive and single-stranded DNA (ssDNA) - positive cells were evaluated using dual-label immunohistochemistry with anticleaved caspase-3 and anti-ssDNA antibodies. In addition, tartrate-resistant acid phosphatase (TRAP)-positive cells in the cellular cementum were evaluated using TRAP histochemical staining. Results: Caspase-3- and ssDNA-positive cells appeared at 12 hours, but were restricted to the compressed periodontal ligament (PDL) and not the cellular cementum. Cleaved caspase-3-positive cementocytes were observed in the cellular cementum adjacent to the compressed PDL on day 1. From days 2 to 4, the number of caspase-3- and ssDNA-positive cementocytes increased. TRAP-positive cells appeared on the cellular cementum at the periphery of the hyalinized tissue on day 7, and resorption progressed into the broad surface of the cementum by day 14. Conclusion: Cementocytes adjacent to the hyalinized tissue underwent apoptotic cell death during orthodontic tooth movement, which might have been associated with subsequent root resorption.

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The effect of alveolar decortication on orthodontically induced root resorption

The Angle Orthodontist ◽

10.2319/051819-344.1 ◽

2020 ◽

Vol 90 (4) ◽

pp. 524-531 ◽

Cited By ~ 1

Author(s):

Po-Jung Chen ◽

Joy H. Chang ◽

Eliane H. Dutra ◽

Ahmad Ahmida ◽

Ravindra Nanda ◽

...

Keyword(s):

Tooth Movement ◽

Root Resorption ◽

Orthodontic Tooth Movement ◽

Control Group ◽

Tartrate Resistant Acid Phosphatase ◽

Micro Computed Tomography ◽

Root Volume ◽

Male Wistar Rats ◽

Group 3 ◽

Group 2

ABSTRACT Objective To determine the effect of alveolar decortication on orthodontically induced root resorption. Materials and Methods A total of 24 male Wistar rats (14 week old) were used. The rats were randomly divided into one of the following three groups: group 1 (control group), orthodontic tooth movement (OTM) for 2 weeks; group 2, OTM for 2 weeks + two alveolar decortications (2AD); group 3, OTM for 2 weeks + four alveolar decortications (4AD). The first molar was moved mesially for 2 weeks. Micro computed tomography was used to analyze root volume. In addition, histological sections were stained with Tartrate Resistant Acid Phosphatase (TRAP) to quantify the osteoclast number. Results The buccal root volume in OTM + 4AD group was decreased by 8.92% and 6.11% when compared with the OTM-only group and OTM + 2AD group, respectively. Similarly, the other four root volumes in the OTM + 4AD group was decreased by 8.99% and 5.24% when compared with the OTM-only group and OTM + 2AD group, respectively. There was a decrease in buccal root density in the OTM + 4AD group by 4.66% and 3.56% when compared with the OTM-only group and the OTM + 2AD group, respectively. In addition, there was an increase in the number of osteoclasts by 195.73% and 98.74% in OTM + 4AD group in comparison with the OTM and OTM + 2AD group. Conclusions The amount of orthodontically induced root resorption was positively correlated with the extent of surgical injury used to accelerate orthodontic tooth movement.

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Effect of supplementary zinc on orthodontic tooth movement in a rat model

Dental Press Journal of Orthodontics ◽

10.1590/2177-6709.21.2.045-050.oar ◽

2016 ◽

Vol 21 (2) ◽

pp. 45-50 ◽

Cited By ~ 4

Author(s):

Mohammad Sadegh Ahmad Akhoundi ◽

Rezvaneh Ghazanfari ◽

Shahroo Etemad-Moghadam ◽

Mojgan Alaeddini ◽

Azam Khorshidian ◽

...

Keyword(s):

Rat Model ◽

Tooth Movement ◽

Root Resorption ◽

Orthodontic Tooth Movement ◽

Cumulative Effect ◽

Study Groups ◽

Model Material ◽

Bone Homeostasis ◽

Male Wistar Rats ◽

Hematoxylin Eosin

ABSTRACT Introduction: Osteoclasts and osteoblasts are responsible for regulating bone homeostasis during which the trace element zinc has been shown to exert a cumulative effect on bone mass by stimulating osteoblastic bone formation and inhibiting osteoclastic bone resorption. Objective: The aim of the present study was to investigate the effects of zinc (Zn) on orthodontic tooth movement (OTM) in a rat model. Material and Methods: A total of 44 male Wistar rats were divided into four groups of 11 animals each and received 0, 1.5, 20 and 50 ppm Zn in distilled water for 60 days. In the last 21 days of the study, nickel-titanium closed coil springs were ligated between maxillary right incisors and first molars of all rats, and tooth movement was measured at the end of this period. Histological analysis of hematoxylin/eosin slides was performed to assess root resorption lacunae, osteoclast number and periodontal ligament (PDL) width. Results: Mean OTM was calculated as 51.8, 49.1, 35.5 and 45 µm in the 0, 1.5, 20 and 50 ppm zinc-receiving groups, respectively. There were no significant differences in neither OTM nor histological parameters among the study groups (p > 0.05). Conclusion: According to the results obtained in the current investigation, increase in supplementary zinc up to 50 ppm does not affect the rate of OTM neither bone and root resorption in rats.

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Compressive Force Induces Osteoblast Apoptosis via Caspase-8

Journal of Dental Research ◽

10.1177/154405910608500307 ◽

2006 ◽

Vol 85 (3) ◽

pp. 240-244 ◽

Cited By ~ 41

Author(s):

Y. Goga ◽

M. Chiba ◽

Y. Shimizu ◽

H. Mitani

Keyword(s):

Cell Death ◽

Caspase 3 ◽

Tooth Movement ◽

Orthodontic Tooth Movement ◽

Compressive Force ◽

Caspase 8 ◽

Dependent Manner ◽

Caspase 9 ◽

Osteoblast Apoptosis

Periodontal remodeling during orthodontic tooth movement is a result of mechanical stresses. The application of excessive orthodontic force induces cell death. However, the nature of compressive force-induced cell death is unclear. We examined whether the in vitro application of continuous compressive force would induce apoptosis in human osteoblast-like cells (MG-63 cells), and investigated the mechanism by which apoptosis was initiated. The cells became aligned irregularly, and cell viability decreased, indicating that the compressive force caused cell death. According to the TUNEL analysis, the number of apoptotic cells increased significantly in a time-and force-dependent manner. Caspase-3 activity increased with the magnitude of the compressive force, and this effect was reduced significantly by a caspase-8 inhibitor, whereas a caspase-9 inhibitor had no such effect. We conclude that the in vitro application of compressive force can induce apoptosis in MG-63 cells through the activation of caspase-3 via the caspase-8 signaling cascade.

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The effects of binge-pattern alcohol consumption on orthodontic tooth movement

Dental Press Journal of Orthodontics ◽

10.1590/2176-9451.19.6.093-098.oar ◽

2014 ◽

Vol 19 (6) ◽

pp. 93-98 ◽

Cited By ~ 7

Author(s):

Cristiano Miranda de Araujo ◽

Aline Cristina Batista Rodrigues Johann ◽

Elisa Souza Camargo ◽

Orlando Motohiro Tanaka

Keyword(s):

Bone Resorption ◽

Saline Solution ◽

Tooth Movement ◽

Orthodontic Tooth Movement ◽

Control Group ◽

Tartrate Resistant Acid Phosphatase ◽

Chi Square ◽

Significance Level ◽

Male Wistar Rats ◽

Chi Square Test

OBJECTIVE: This study aimed to assess tissue changes during orthodontic movement after binge-pattern ethanol 20% exposure.METHODS: Male Wistar rats (n = 54) were divided into two groups. The control group (CG) received 0.9% saline solution, while the experimental group (EG) received 20% ethanol in 0.9% saline solution (3 g/kg/day). On the 30th day, a force of 25 cN was applied with a nickel-titanium closed coil spring to move the maxillary right first molar mesially. The groups were further divided into three subgroups (2, 14 and 28 days). Tartrate-resistant acid phosphatase and picrosirius were used to assess bone resorption and neoformation, respectively. Data were compared by two-way ANOVA, Tukey's HSD, Games-Howell and chi-square test. Significance level was set at 5%.RESULTS: There was a decrease in the number of osteoclasts in EG at day 28. The percentage of collagen showed no interaction between group and time.CONCLUSION: Binge-pattern 20% ethanol promoted less bone resorption at the end of tooth movement, thereby suggesting delay in tooth movement.

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Infrared Light-Emitting Diode (LED) Effects on Orthodontic Tooth Movement

Brazilian Dental Journal ◽

10.1590/0103-6440201902416 ◽

2019 ◽

Vol 30 (4) ◽

pp. 410-416 ◽

Cited By ~ 1

Author(s):

Simone Peixe Friedrichsdorf ◽

Victor Elias Arana-Chavez ◽

Vivian Bradaschia-Correa ◽

Paolo Maria Cattaneo ◽

Gladys Cristina Dominguez

Keyword(s):

Tooth Movement ◽

Root Resorption ◽

Light Emitting Diode ◽

Histological Study ◽

Orthodontic Tooth Movement ◽

Infrared Light ◽

Tartrate Resistant Acid Phosphatase ◽

Micro Computed Tomography ◽

Led Phototherapy ◽

Significant Difference

Abstract The present study aimed to analyze the effect of LED phototherapy on the presence of hyalinization and root resorption during orthodontic tooth movement (OTM) in rats and to measure the amount of tooth movement. Eighty rats were allocated into two groups: LED and control (CON), where the LED rats were irradiated with infrared LED (850 nm, 30 mW) for 5 min during the first five days of OTM and where controls were not irradiated. Both groups were subdivided into four subgroups (n=10) according to the date of euthanasia (4, 7, 14 and 21 days). Five out of ten LED21 and five of ten CON21 rats were submitted to micro-computed tomography (μCT); μCT scans were taken on days 0, 7, 14 and 21. For histological study, maxillae were processed to light microscopy using Hematoxylin-Eosin (HE) and Tartrate-Resistant Acid Phosphatase (TRAP) histochemistry. The amount of tooth movement did not differ between LED and CON. Hyalinization was observed at the pressure areas in both groups, and it did not show a statistically significant difference between the groups. Root resorption was also observed in both groups after 7 days and it did not represent any differences between the two groups. LED phototherapy was not able to increase the amount of OTM. Similar characteristics of hyalinization and root resorption were observed in both groups.

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The effect of the extent of surgical insult on orthodontic tooth movement

European Journal of Orthodontics ◽

10.1093/ejo/cjz006 ◽

2019 ◽

Vol 41 (6) ◽

pp. 601-608 ◽

Cited By ~ 6

Author(s):

Joy Chang ◽

Po-Jung Chen ◽

Eliane H Dutra ◽

Ravindra Nanda ◽

Sumit Yadav

Keyword(s):

Wistar Rats ◽

Alveolar Bone ◽

Tooth Movement ◽

Orthodontic Tooth Movement ◽

Primary Objective ◽

Bone Volume ◽

Tartrate Resistant Acid Phosphatase ◽

Trabecular Thickness ◽

Tissue Density ◽

Male Wistar Rats

Abstract Objective The primary objective of this study was to investigate how the extent of surgical insult affects the orthodontic tooth movement (OTM) and the alveolar bone modelling and remodelling in a rodent model. Material and methods 15-week-old male Wistar rats were used in the research and they were randomly divided into three treatment groups: (1) OTM only (N = 8); (2) OTM + 2 alveolar decortication (AD) (less surgical insult) (N = 8); and (3) OTM + 4 AD (more surgical insult) (N = 8). A nickel-titanium spring delivering 5–8 g of force was used to protract the molar mesially using maxillary incisors as an anchorage. AD was done using a hand piece and a round bur, adjacent to the left first maxillary molar on the palatal alveolar bone. After 14 days of OTM Wistar rats were killed and microfocus computed tomography and histological analysis were performed. Results The OTM + 4AD group presented with a significant increase (P < 0.05) in the rate of tooth movement when compared to OTM + 2AD group and OTM only group. In addition, the OTM + 4AD group had a significant decrease in bone volume and tissue density (P < 0.05) and a significant increase (P < 0.05) in the trabecular spacing and trabecular thickness when compared to OTM only. Histological quantification of tartrate-resistant acid phosphatase indicated a significant percent increase (P < 0.05) in OTM + 4AD group, when compared to OTM + 2AD and OTM only group. Results Increased surgical insult increases the rate of OTM. Additionally, increased surgical insult decreases the bone volume and the tissue density.

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Ultrasound enhances the healing of orthodontically induced root resorption in rats

The Angle Orthodontist ◽

10.2319/030711-164.1 ◽

2011 ◽

Vol 82 (1) ◽

pp. 48-55 ◽

Cited By ~ 23

Author(s):

Zhifeng Liu ◽

Juan Xu ◽

Lingling E ◽

Dongsheng Wang

Keyword(s):

Tooth Movement ◽

Root Resorption ◽

Osteoclast Differentiation ◽

Orthodontic Tooth Movement ◽

Cell Number ◽

Positive Control ◽

Negative Control ◽

Tartrate Resistant Acid Phosphatase ◽

Activity Levels ◽

Tissue Slices

Abstract Objective: To examine the effect of low-intensity pulsed ultrasound (LIPUS) on orthodontically induced root resorption in rats. Materials and Methods: Sixty-four male Wistar rats were divided randomly and equally into four groups (n = 16 rats each). The rats were untreated (negative control) or treated with orthodontic tooth movement without (positive control) or with LIPUS at 100 or 150 MW/cm2 (LIPUS-treated groups). An initial force of 100 g was applied to the areas between the upper right central incisors and the first molars of the rats for 10 days. Eight rats were randomly chosen from each group, and the root resorption index (RRI) was determined with scanning electron microscopy (SEM). Upper first molar-centered mesial-distal tissue slices were generated from the upper first molars and peridentium of the remaining eight rats from each group. Specimen slices were analyzed with hematoxylin-eosin and tartrate-resistant acid phosphatase staining, osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) immunohistochemistry, and optical microscopy. Analyses of cell number, densitometry, and one-way analysis of variance were performed. Results: The LIPUS-treated groups displayed decreased RRI values, decreased osteoclast numbers and activity levels, and increased OPG/RANKL expression ratios. High-power SEM revealed reparative cementum in the LIPUS-treated samples. Conclusion: LIPUS regulates osteoclast differentiation via the OPG/RANKL ratio, evoking a reparative effect on orthodontically induced root resorption in rats.

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Correlation of IL-17 level in gingival crevicular fluid of orthodontically induced inflammatory root resorption

10.1101/627059 ◽

2019 ◽

Author(s):

Hua Zhou ◽

Xiao Liang ◽

Aipeng Liu ◽

Dongmei Nong ◽

Yaqing Qin ◽

...

Keyword(s):

Alveolar Bone ◽

Tooth Movement ◽

Root Resorption ◽

Early Stage ◽

Morphological Changes ◽

Orthodontic Tooth Movement ◽

Nickel Titanium ◽

Tartrate Resistant Acid Phosphatase ◽

Periodontal Tissues ◽

Osteoclast Number

ABSTRACTObjectiveTo investigate IL-17 expression in orthodontic tooth movement and orthodontic nickel-titanium spring-induced inflammatory root resorption.MethodsOrthodontic nickel-titanium springs were ligated between the bilateral maxillary first molar and the incisors of the rats to establish a rat model of orthodontic tooth movement (OTM), each rat was subjected to two cycles of near-GCF and peripheral blood serum collection before and after force application, and IL-17 levels in GCF and serum were measured quantitatively by ELISA. Morphological changes in periodontal tissue and root of the experimental dentine were evaluated by hematoxylin and eosin staining. Tartrate-resistant acid phosphatase staining and immunohistochemistry were used to determine the osteoclast number and expression changes in IL-17, receptor activator of nuclear factor kappa-B ligand (RANKL), and osteoprotegerin (OPG) in the periodontal tissues, respectively, on the pressure side of the experimental tooth.ResultsIL-17 was detected in GCF and serum. The pressure area exhibited alveolar bone resorption only at a force of 20g. Additionally, a force of 60g led to root resorption. IL-17, RANKL/OPG and osteoclast number showed similar trend that all expressed increasing high level at early stage, then significantly decreased from days 5 to 14, and revealed 60g group the highest expression level while 0g group the lowest.The change in the IL-17 level in the GCF was strongly correlated with IL-17 and RANKL/OPG expression levels and osteoclast numbers in the periodontal ligament.ConclusionsThe results indicated that measuring IL-17 level in GCF can predict the risk of alveolar bone and root resorption induced by orthodontic treatment.

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Injectable RANKL sustained release formulations to accelerate orthodontic tooth movement

European Journal of Orthodontics ◽

10.1093/ejo/cjz027 ◽

2019 ◽

Vol 42 (3) ◽

pp. 317-325 ◽

Cited By ~ 2

Author(s):

Joy H Chang ◽

Po-Jung Chen ◽

Michael R Arul ◽

Eliane H Dutra ◽

Ravindra Nanda ◽

...

Keyword(s):

Tooth Movement ◽

Root Resorption ◽

Volume Fraction ◽

Treatment Time ◽

Orthodontic Tooth Movement ◽

Hydroxyethyl Cellulose ◽

Poly Lactic Acid ◽

Tartrate Resistant Acid Phosphatase ◽

Coil Spring ◽

Control Groups

Summary Background Accelerating orthodontic tooth movement (OTM) through biologically effective methods, such as increasing osteoclast-mediated alveolar resorption, could effectively shorten treatment time. Objective To evaluate an injectable formulation containing receptor activator of nuclear factor kappa-B ligand (RANKL) on the OTM. Materials and methods We fabricated a RANKL formulation from 100 µl of 100 µg/ml RANKL adsorbed on 10 mg of poly(lactic acid-co-glycolic acid) microspheres embedded in a 10 wt% aqueous hydroxyethyl cellulose carrier gel. We characterized these formulations for the rate of RANKL release, and then tested for bioactivity using in vitro cell culture. In vivo OTM studies were conducted using 15 week old male Wistar rats for 14 days. We injected the RANKL formulations palatal to the left maxillary first molar and accomplished OTM with a nickel–titanium (NiTi) coil spring applying 5–8 g force. Control groups involved the application of NiTi coil spring with and without placebo formulation. The outcome measure included the distance of tooth movement, bone volume fraction, tissue density, and root volume determined with micro-computed tomography. We determined the amount of osteoclast activity using tartrate-resistant acid phosphatase (TRAP) staining. Results These formulations were able to sustain the release of RANKL for more than 30 days, and the released RANKL showed a positive effect on mice osteoclast precursor cells (RAW 264.7). Reported injectable RANKL formulations were effective in accelerating OTM compared with other control groups, with 129.2 per cent more tooth movement than no formulation and 71.8 per cent more than placebo formulation, corresponding with a significant increase in the amount of TRAP activity. We did not observe any significant differences in root resorption between the groups. Conclusion Our study shows a significant increase in OTM with injectable formulations containing RANKL.

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Effects of Short- and Long-Term Celecoxib on Orthodontic Tooth Movement

The Angle Orthodontist ◽

10.2319/100207-474.1 ◽

2008 ◽

Vol 78 (5) ◽

pp. 860-865 ◽

Cited By ~ 17

Author(s):

Gustavo Hauber Gameiro ◽

Darcy Flávio Nouer ◽

João Sarmento Pereira Neto ◽

Vânia Célia Siqueira ◽

Eduardo Dias Andrade ◽

...

Keyword(s):

Alveolar Bone ◽

Tooth Movement ◽

Orthodontic Tooth Movement ◽

Experimental Period ◽

Term Therapy ◽

Tartrate Resistant Acid Phosphatase ◽

Male Wistar Rats ◽

Short And Long Term ◽

Long Term Therapy

Abstract Objective: To test the hypothesis that short- and long-term celecoxib administration has no effect on orthodontic tooth movement. Materials and Methods: Male Wistar rats were submitted to short- (3 days) and long-term (14 days) celecoxib administration, while the respective control groups received equivolumetric saline intraperitoneal injections. The upper left first molars of all rats were moved mesially for 14 days by a fixed orthodontic appliance exerting 50 g force upon insertion. After the experimental period, tooth movement was quantified and tissues around the first molar were processed for tartrate-resistant acid phosphatase (TRAP) histochemistry. The amount of tooth movement and the number of TRAP-positive cells on the alveolar bone surface were evaluated. Results: The amount of tooth movement was significantly reduced in rats submitted to short- and long-term celecoxib administration, while the number of osteoclasts on the alveolar bone did not differ between the four groups studied. Conclusions: The hypothesis is rejected. Although celecoxib administration did not affect the number of osteoclasts, the osteoclast activity might be reduced, which could explain the inhibition of tooth movement observed in the celecoxib-treated animals. These results indicate that orthodontists should be aware of patients under short- and long-term therapy with celecoxib.

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