ARTICLE | doi:10.20944/preprints201902.0169.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: Tooth size; Tooth size discrepancy; Bolton ratios; Meta-analysis; Systematic review
Online: 18 February 2019 (17:17:20 CET)
Introduction: The purposes of this study were to seek for overall ratio (OR) and anterior ratio (AR) patients data in normal occlusion and Angle’s malocclusion studies, and to assess if such results support Bolton’s standards as general references. Methods: Pubmed, Medline, CENTRAL and Scholar databases were searched up to February 2018 (CRD42018088438). Gray literature was explored through OpenGray. Non-randomized clinical studies, published in English and assessing Bolton’s OR and AR in normal occlusion and Angle’s malocclusion groups (Class I, Class II, Class II division 1, Class 2 division 2, Class III) patients were included. OR and AR means and standard deviations (SD) were collected. Potential covariates (study design, publication year, country where the study was conducted, number of cases, gender, mesiodistal measurement method, and calibration method) were also extracted. The National Health Heart Lung, and Blood Institute’s Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies was used to assess each included studies quality. Pairwise Random-Effects and Multilevel Bayesian Network Meta-Analyses were used to synthesize available data. Results: Fifty-two observational studies were included (8872 participants; male/females 2674/3272; 16 studies lacked gender information). For normal occlusion, global pooled estimates for OR and AR means were 91.74% (95% CI: 91.37-92.10) and 78.24% (95% CI: 77.85-78.63), respectively. We could identify on Angle’s Class III patients meaningful OR and AR mean deviations from normal occlusion (0.89, 95% credible interval [CrI], 0.66-1.12, and 0.66, 95% CrI, 0.38-0.94, respectively), while on Class I patients we found a meaningful mean deviation from normal occlusion only for OR (0.25, 95% CrI, 0.03-0.47). Concerning gender impact, male patients presented higher OR (0.30, 95% CI 0.00-0.59) and AR (0.41, 95% CI 0.00-0.83) mean values than females in Class I. Conclusions: The results show that global pooled OR and AR mean values for normal occlusion patients are slightly above Bolton’s original values. Class I, for OR mean values, and Class III, for both OR and AR, are proportionally larger than normal occlusion patients. Gender had almost no impact on teeth mesiodistal proportion.
CASE REPORT | doi:10.20944/preprints201808.0378.v1
Online: 21 August 2018 (13:49:34 CEST)
Aim: In a human pilot case, we used a root formed temporary prosthetical device (Intra-alveolar Device - IAD), to investigate the effect of mechanical stimulation on hard tissue clinically and radiographically. Background: The extraction of a tooth determines the resorption of the alveolar bone. This determines challenge to place an implant and to integrate the prosthesis in soft tissue. Mechanical stimulation is fundamental for bone tropism but is not understood the effect of mechanical stimulation on post-extraction site. Case presentation: A 24 years old woman was enrolled. The IAD’s were used as expected by protocol. Clinical healing was uneventfully. Vertical radiographical bone resorption measured on CBCT was -0,14mm (5,6%) while horizontal bone resorption was -0,21mm (12,36%). Conclusion: This study demonstrated the feasibility of the proposed model. We need clinical prospectical studies enrolling more patients
Online: 28 August 2020 (15:06:48 CEST)
Tooth bud removal called Ibyinyo is the practice of removing the developing tooth buds, usually done on an infant, typically performed by traditional healers who believe that this practice will reduce fever and diarrhea in children. This practice is most prevalent in East-African countries, including Rwanda. These procedures are mostly performed in non-sterile conditions using basic sharp instruments. We will discuss the case of a 10-year-old female patient who was presented at the dental clinic, with two malformed permanent canine teeth. Clinical examination revealed malformed enamel and elongated permanent right maxillary canine tooth left mandibular canine tooth with crown malformation. She was also presented with retained (primary) left maxillary lateral incisor tooth and missing left maxillary canine tooth. In addition, the ectopic eruption of left maxillary central incisor tooth and missing permanent right mandibular canine tooth were noted. All these complications resulted from tooth bud removal that the patient had experienced in her early childhood. Her malformed right maxillary and left lower mandibular canine teeth were reshaped, using composite filling materials, to improve her appearance aesthetically. Ibyinyo is preventable damage, done out of ignorance and superstitious practices that can be stopped by growing social awareness. Therefore, educating parents through community-based campaigns on the detrimental consequences of early childhood tooth bud removal through Ibyinyo practice might be helpful to eradicate this harmful and unnecessary practice.
ARTICLE | doi:10.20944/preprints201804.0075.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: high frequency; acceleration; vibration; orthodontics; tooth movement
Online: 6 April 2018 (10:57:40 CEST)
Evaluation of the effect of a high frequency acceleration device on clear aligner exchange intervals and treatment time required to achieve prescribed tooth movements. Sixteen subjects with similar Class I malocclusions, 5mm or less crowding, and treated with Invisalign were divided into two groups. Group 1 (experimental; N=8) underwent aligner treatment in conjunction with daily use of the high frequency acceleration device and exchanged aligners every 5 days. Group 2 (controls; N=8) underwent aligner treatment without use of the device and exchanged aligners every 14 days according to the manufacturer's recommended interval. All subjects were treated by one investigator, and results were evaluated by both; total number of aligners used, and number of refinements required, prior to final Vivera retention scan. A significant decrease in both treatment time, and number of aligners required to complete treatment was observed by experimental subjects as compared to controls. In addition, no refinements were required by experimental subjects, whereas 6 of 8 of the control subjects required 1 or more refinements. Use of the high frequency acceleration device in conjunction with Invisalign treatment resulted in more predictable tooth movement and a significant decrease in the length of treatment.
REVIEW | doi:10.20944/preprints201705.0159.v1
Online: 22 May 2017 (07:36:30 CEST)
A review of the surface ablation of hominin teeth by attrition, abrasion and erosive wear. The occurrence of these lesions is explored in a sample of South African fossil australopithecine dentitions revealing excessive wear. Interpretation of the nature of the dietary components causing such wear in the absence of carious erosion provides insight into the ecology of the Plio-pleistocene epoch (1-2 million years ago). Fossil teeth inform much of the living past by their retained evidence after death. Tooth wear is the ultimate forensic evidence of lives lived.
ARTICLE | doi:10.20944/preprints201809.0334.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: Adhesive, Dentin, Composite, Adaptation, Tooth, Optical coherence tomography, Gap
Online: 18 September 2018 (08:52:54 CEST)
Objectives: The current study aimed to compare the adaptation of the restored class-I cavities with two self-etch adhesives bonded to two resin composite using cross-polarization optical coherence tomography (CP-OCT). Materials and Methods: Cylindrical class-I cavities were prepared on twenty, extracted human premolars. Two self-etch adhesives; Clearfil SE bond 2 (SE; Kuraray Noritake Dental, Japan) and Bond Force (Palfique Bond) adhesive (PL; Tokuyama Dental, Japan) were used in this study that were bonded to either resin composites materials; Herculite XRV microhybrid dental composite (HRV; Kerr, Italy) or Estelite Alpha composite (ESA; Tokuyama Dental, Japan). The specimens were divided into four groups (n=5); SE-HRV, SE-ESA, PL-HRV and PL-ESA. All specimens were varnished and stored in distilled water for 24h. Then, they were submerged in a contrasting medium. After that, all groups were optically imaged under CP-OCT at every 250 µm interval distance. Later, image binarization and gap quantification were carried out using Image analysis software. Result: There was a significant difference between all the groups except between SE-ESA and PL-ESA (p = 0.51). The highest median gap % was seen in PL-HRV group followed by SE-ESA, PL-ESA and SE-HRV. Conclusion: Other than composite filler loading and adhesive formula, the interactions of the adhesive and composite copolymers have great influence on composite adaptation.
BRIEF REPORT | doi:10.20944/preprints202007.0734.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: cannabinoid; CBD; dental care; dental plaque; tooth polish; polishing powder
Online: 31 July 2020 (06:02:24 CEST)
Introduction: Dental health problems including dental plaque are common health problems affecting people of different age groups globally. Air-polishing is a safe tooth polishing technique used by dental professionals for stain and plaque removal and as preventive procedure for dental health. Here we report the technical improvisation of existing air-polishing technique by supplementing cannabinoid powder into the classic polishing powder for effective removal of supragingival and subgingival plaque and inhibition of plaque forming bacteria. Methods: The cannabidiol (CBD) powder was added to the tooth polishing powder (AIR-N-GO, classic) at 1% (wt/wt) ratio. The study was conducted on 12 patients, of which 6 received regular polishing treatment and 6 received CBD-supplemented polishing treatment. The dental plaque samples were collected before and after each treatment and subjected to in vitro microbiological analysis and the colony forming units (CFU) were analyzed using automated colony counter. Results: Based on in vitro microbiological analysis, the average CFU of interdental space samples collected from post-CBD-supplemented polishing treatment was significantly reduced (linear fold change between 3.9-18.4) compared to that of post-regular polishing (linear fold change between 1.0-2.6) treatment. Conclusions: CBD-supplemented polishing powder can help in effective removal and killing of dental plaque bacteria during the polishing treatment. CBD powder can be added as enhancing supplement to the existing polishing powders.
ARTICLE | doi:10.20944/preprints202212.0332.v1
Subject: Materials Science, Biomaterials Keywords: Biomechanics; Orthodontic force; Torque; Tooth Movement; Removable Thermoplastic Appliance; Aging; Aligners
Online: 19 December 2022 (09:10:51 CET)
The aim of this study is to study the effect of aging in different media (deionized water and artificial saliva) on the force/torque generation by thermoplastic orthodontic aligners. Ten thermoformed aligners made of Essix ACE® thermoplastic sheets were aged in deionized water and in artificial saliva over two weeks at 37 C, five in each medium. The force/torque generated on upper second premolar (Tooth 25) of a resin model was measured at day 0 (before aging), 2, 4, 6, 10, and 14, using a biomechanical test set-up. The results showed that the thermocycling of aligners has no significant impact on their force/torque decay. No significant differences were also found in force/torque between the aligners stored in deionized water nor artificial saliva. The vertical extrusion-intrusion forces were measured in the range of 1.4 to 4.6 N, the horizontal oro-vestibular forces were 1.3 to 2.5 N, while the torques on mesio-distal rotation were 5.4 to 41.7 Nmm. It could be concluded that the influence of saliva on the mechanical properties can be classified as insignificant, and no significant difference between artificial aging in deionized water or artificial saliva was observed.
ARTICLE | doi:10.20944/preprints202011.0455.v1
Subject: Medicine & Pharmacology, Allergology Keywords: NHANES; periodontal diseases; periodontitis; tooth loss; inflammation; diet; nutrition; oral health
Online: 17 November 2020 (14:44:20 CET)
Background: We aimed to assess the association between DII and PD and the mediation effect of DII in the association of PD with systemic inflammation. Using the National Health and Nutrition Examination Survey (NHANES) 2009-2010, 2011-2012 and 2013-2014, participants that received periodontal exam and provided dietary recall data were included. The inflammatory potential of diet was calculated via DII. Periodontitis was defined according to the 2012 case definition. The clinical outcomes of interest were mean periodontal probing (PPD), mean clinical attachment loss (CAL) and thresholds of PPD and CAL. White blood cells (WBC), segmented neutrophils and C-reactive protein (CRP) were used as proxies for systemic inflammation. The periodontal measures were regressed across DII values using adjusted multivariate linear regression. Adjusted mediation analysis appraised the influence of DII in the association of periodontitis and systemic inflammation. 10,178 participants were included. DII was significantly correlated with mean PPD, mean CAL, thresholds of PPD and CAL, WBC, segmented neutrophils and DII (p<0.01). A linear regression logistic adjusted for multiple confounding variables confirmed the association between DII and mean PPD (B = 0.02, Standard Error [SE]: 0.02, p<0.001) and CAL (B = -0.02, SE: 0.01, p<0.001). The association of mean PPD and mean CAL with both white blood cells and segmented neutrophils were mediated by DII (from 2.1 to 3.5%, p<0.001). In the 2009-2010 subset, the association of mean CAL with serum CRP was mediated by DII (52.0%, p<0.01). In conclusion, inflammatory diet and PD may be associated. Also, the inflammatory diet significantly mediated the association of leukocyte counts and systemic inflammation with periodontitis.
REVIEW | doi:10.20944/preprints202011.0227.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Organelle transport; Charcot-Marie-Tooth; Axonal transport deficiency; Neurodegeneration; Cytoskeleton; Mitochondria
Online: 6 November 2020 (08:55:15 CET)
Charcot-Marie-Tooth (CMT) disease is the most commonly inherited neurological disorder, defined by progressive deterioration of the peripheral nerves. Clinical manifestations of CMT mutations are typically limited to peripheral neurons, the longest cells in the body. Currently, mutations in at least 80 different genes are associated with CMT and new mutations are regularly being discovered. A large portion of the proteins mutated in axonal CMT have documented roles in mitochondrial mobility. This suggests that trafficking defects may be a common underlying mechanism in CMT. This review will focus on the potential role of altered mitochondrial mobility in the pathogenesis of axonal CMT, highlighting the challenges and opportunities to this “impaired mobility” model of the disease.
ARTICLE | doi:10.20944/preprints202201.0321.v1
Subject: Life Sciences, Molecular Biology Keywords: Periodontitis; Tooth movement; Obesity; Palmitic Acid; Histone Modification; Inflammation; COX2/PGE2; IL10
Online: 21 January 2022 (12:50:31 CET)
The interrelationship between periodontal disease, obesity-related hyperlipidemia and mechanical forces as well as their modulating effects on the epigenetic profile of periodontal ligament (PdL) cells are assumed to be remarkably complex. The PdL serves as connective tissue between teeth and alveolar bone for pathogen defense and inflammatory response to mechanical stimuli occurring during tooth movement. Altered inflammatory signaling could promote root resorption and tooth loss. Hyperinflammatory COX2/PGE2 signaling was reported for human PdL fibroblasts (HPdLF) concomitantly stressed with P. gingivalis lipopolysaccharides and compressive force after exposure to palmitic acid (PA). The aim of this study was to investigate to what extent this is modulated by global and gene-specific changes in histone modifications. Quantitative expression of epigenetic key players and global H3Kac as well as H3K27me3 levels were evaluated in dual stressed HPdLF exposed to PA revealing a decreased force-related reduction in repressive H3K27me3. UNC1999-induced H3K27me3 inhibition reversed the hyperinflammatory response of dual-stressed PA-cultures characterized by COX2 expression, PGE2 secretion and THP1 adhesion. Reduced expression of the anti-inflammatory cytokine IL10 and increased association of H3K27me3 at its promoter-associated sites were reversed by inhibitor treatment. Thus, the data highlight an important epigenetic interplay between different stimuli to which the PdL is exposed.
ARTICLE | doi:10.20944/preprints202201.0043.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: Photobiomodulation; low level laser therapy; ectopic eye tooth; root resorption; treatment modalities.
Online: 5 January 2022 (13:15:17 CET)
The orthodontic treatment brings numerous benefits and, in most cases, the benefits outweigh the possible disadvantages. Root resorption (RR) is a common adverse phenomenon associated with orthodontic treatment. This study evaluates the role of low-level laser emission / Photobiomodu-lation (LE/P) in quantitative measurements of root resorption (QRR). The application of LE/P was done after each orthodontic activation with 4 types of treatment intervention (TI) on the RR after fixed orthodontic treatment (FOT) of the upper arch with ectopic eye tooth/teeth [EET]. 32 Orthodontic patients scheduled for FOT were selected and assigned to the 4 groups. These were LE/P+Self ligating bracket (SLB), LE/P+Conventional bracket (CB), Non-Photobiomodulation (non-LE/P)+SLB, and non-LE/P+CB. Standard management stages of FOT were followed in the maxilla. Each patient received a single application of LE/P labially/buccally and palatally, a total of 5 different points during each activation or appointment. The main outcome measure was QRR in maxillary anteriors before and after FOT assessed via cone-beam computed tomography (CBCT) using 3D OnDemand software. Insignificant QRR was found between before and after FOT in SLB, CLB, and LE/P, non-LE/P groups (p > 0.05). QRR in the SLB vs CB and LE/P vs non-LE/P group was significantly different in 11, 13, and 23 (p < 0.05). QRR in the LE/P+SLB group (p < 0.05) was significantly different in 11, 13, and 23 than that in the other groups. The most severe QRR was found on the 13 (0.88 ± 0.28mm and 0.87±0.27mm) and 23 (1.19 ± 0.14 mm and 1.16±0.13mm) in the CB and non-LE/P group (p < 0.001). LE/P+SLB showed highly significant superior outcome (p < 0.001) in relation to non-LE/P+CB, the QRR of 23 were 0.813± 0.114mm and 1.156± 0.166mm respectively. Significantly higher amount of QRR found in EET patients after FOT treated with the CB, non-LE/P, and non-LE/P+CB system and warrants further investigation to explore potential specific causes.
ARTICLE | doi:10.20944/preprints202104.0009.v1
Subject: Medicine & Pharmacology, Allergology Keywords: chewing ability; functional tooth unit; masticatory performance; masseter muscle; mixing ability index
Online: 1 April 2021 (10:25:29 CEST)
While appropriate nutrient intake is important for older adults, various oral problems cause de-creased masticatory function. This cross-sectional study aimed to identify the factors associated with decreased masticatory performance in older adults. Oral examinations were performed on 80 participants (mean age: 75.10 ± 5.64 years) to determine the number of functional tooth units (FTUs). Symptoms of periodontal and temporomandibular diseases were evaluated via a ques-tionnaire. The tone, elasticity, and dynamic stiffness of the masseter muscle were measured using the Myoton® PRO device. The mixing ability test was used to assess the masticatory performance and the mixing ability index (MAI) was calculated. The analysis of covariance test was performed to adjust for confounding factors and multiple logistic regression analysis was performed to identify the risk factors affecting MAI. A lower MAI was significantly associated with higher tone (p = 0.006) and lower elasticity (p = 0.013). The number of FTUs (adjusted odds ratio [OR] = 0.724, p = 0.029), tone (adjusted OR = 1.215, p = 0.016), and elasticity (adjusted OR = 4.789, p = 0.038) were independently associated with the MAI. Muscle function training and prosthetic treatments may help increase masticatory performance in older adults, which will improve overall health.
ARTICLE | doi:10.20944/preprints202101.0398.v1
Subject: Materials Science, Biomaterials Keywords: self-assembling peptide; biomineralization; pulp-dentin complex; tooth repair; cell migration; biocompatibility
Online: 20 January 2021 (12:55:47 CET)
Self-assembling peptide P11-4 is amphiphilic and pH-triggered with demonstrated effectivity repairing early carious lesions in enamel. However, P11-4 effects on dentin biomineralization and repair remain unexplored. Thus, cytocompatibility and effectiveness of P11-4 inducing mineralization and migration of odontoblast-like cells (MDPC-23) were investigated. MDPC-23 were seeded in contact with P11-4(0.5µg/ml and 1µg/ml), Dentin Matrix Protein 1 (DMP1 0.5µg/ml and 1 µg/ml) or Calcium hydroxide (Ca(OH)2 100µg/ml) solutions. Cytotoxicity was verified using MTT (n=6/group). Mineralization was tested using Alizarin Red (n=4/group). Cell migration was assessed by light microscopy (n=2/group). MTT and Alizarin Red data were compared using Krus-kal-Wallis and Mann-Whitney (α=0.05). P11-4 (0.5µg/ml and 1µg/ml) and DMP1 (0.5µg/ml and 1µg/ml) presented the highest cytocompatibility; Ca(OH)2 presented the lowest. DMP1 1µg/ml exhibited the highest mineralization ability, with no difference to P11-4 1µg/ml. Ca(OH)2 presented lower values than DMP1 1µg/ml (p<0.05), but similar to P11-4 1µg/ml. P11-4 and DMP1 at 0.5 µg/ml showed induced less mineralization than P11-4 and DMP1 at 1µg/ml (p<0.05), with no difference to Ca(OH)2. All materials stimulated cell migration, however, lower concentrations of DMP1 and P11-4 provided better results. P11-4 is cytocompatible, induces mineralization and MDPC-23 migration like DMP1. P11-4 could be an alternative for dentin mineralization and tooth repair.
ARTICLE | doi:10.20944/preprints201809.0273.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: Low level laser therapy; diode laser; Orthodontic tooth movement; Pain; Split-mouth clinical trial
Online: 15 September 2018 (18:18:29 CEST)
This study evaluated the effect of low-level laser irradiation induces by diode laser on the speed of orthodontic tooth movement of canines submitted to initial retraction. Twenty-four mandibular canines were retracted by using NiTi spring (force of 150 g/side). Thirteen of those were irradiated with a diode laser 980-nm diode laser (Wiser Laser Doctor Smile, Lambda) operating at an 810-nm wavelength (1 W of output power, continuous wave of 66.7 J/cm2) that was equipped with a 0.6-mm optical fiber in continuous-wave mode. The canine retraction was accomplished by using prefabricated coil springs. The right of the mandible was chosen to be irradiated with the laser, whereas the left side was considered the control without laser irradiation. The laser was applied with 0-, 3-, 7-, and 14-day intervals. The amount of canine retraction was measured with a digital electronic caliper while the pain level was prompted by a patient questionnaire. The speed of tooth movement was significantly greater in the laser group than in the control group. The pain intensity was also at a lower level in the laser group. Our findings suggest that diode laser therapy can highly accelerate tooth movement during orthodontic treatment and can also effectively reduce pain level.
ARTICLE | doi:10.20944/preprints202101.0090.v1
Subject: Medicine & Pharmacology, Allergology Keywords: periodontal disease; periodontitis; early tooth loss; predictive model; risk factors; oral health; public health; epidemiology
Online: 5 January 2021 (13:03:13 CET)
The aim of this study was to develop and validate a predictive early tooth loss multivariable model for periodontitis patients before periodontal treatment. A total of 544 patients seeking periodontal care at a university dental hospital were enrolled in the study. Teeth extracted after periodontal diagnosis and due to periodontal reasons were recorded. Clinical and sociodemographic variables were analyzed, considering the risk of short-term tooth loss. This study followed the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines for development and validation, with two cohorts considered as follows: 455 patients in the development phase and 99 in the validation phase. As a result, it was possible to compute a predictive model based on tooth type and clinical attachment loss. The model explained 25.3% of the total variability and correctly ranked 98.9% of the cases. The final reduced model area under the curve (AUC) was 0.809 (95% Confidence Interval (95% CI): 0.629 - 0.989) for the validation sample and 0.920 (95% CI: 0.891 - 0.950) for the development cohort. The established model presented adequate prediction potential of early tooth loss due to periodontitis. This model may have clinical and epidemiologic relevance towards the prediction of tooth loss burden.
ARTICLE | doi:10.20944/preprints202012.0579.v1
Subject: Physical Sciences, Acoustics Keywords: Korteweg-de Vries-Burgers equation; cylindrical and spherical waves; saw-tooth solutions; periodic boundary conditions; head shock wave
Online: 23 December 2020 (09:44:50 CET)
For the KdV-Burgers equations on cylindrical and spherical waves the development of a regular profile starting from an equilibrium under a periodic perturbation at the boundary is studied. The equations describe a medium which is both dissipative and dispersive. Symmetries, invariant solutions and conservation laws are investigated. For an appropriate combination of dispersion and dissipation the asymptotic profile looks like a periodical chain of shock fronts with a decreasing amplitude (sawtooth waves). The development of such a profile is preceded by a head shock of a constant height and equal velocity which depends on spatial dimension as well as on integral characteristics of boundary condition; an explicit asymptotic for this head shock and a median of the oscillating part is found.
ARTICLE | doi:10.20944/preprints201807.0321.v1
Subject: Life Sciences, Molecular Biology Keywords: MicroRNA; osteoprotegerin (OPG); orthodontic tooth movement (OTM); miR-3198; mechanical stresses; periodontal ligament cells (PDL cells); compression; tension
Online: 18 July 2018 (08:58:19 CEST)
Background: Osteoclastic bone resorption in the compression zone of periodontal ligament (PDL) plays a role in orthodontic tooth movement, and is regulated by the balance of RANKL and OPG. Compression downregulates OPG, conversely, tension upregulates OPG in PDL cells. However, the regulatory mechanism of OPG expression in PDL cells under different mechanical stresses remains unclear. Methods: To study microRNA (miRNA) expression profiles, compression (2g/cm2) or tension (15%-elongation) was applied to immortalized human PDL (HPL) cells, and miRNA was extracted. The miRNA expression was analyzed using a human miRNA microarray, and the changes of the miRNA expression were confirmed by real-time RT-PCR. In addition, miR-3198-mimic and -inhibitor were transfected into HPL cells to understand the resulting OPG expression and production. Results: Certain miRNAs were expressed differentially under compression and tension. Some miRNAs including miR-3198 were upregulated only by compression. Real-time RT-PCR confirmed that compression induced miR-3198, but tension reduced it, in HPL cells. miR-3198-inhibitor upregulated and miR-3198-mimic reduced OPG in HPL cells. miR-3198-inhibitor rescued the compression-mediated downregulation of OPG. On the other hand, miR-3198-mimic reduced OPG expression under tension. Conclusion: We conclude that miR-3198 is upregulated by compression and is downregulated by tension, suggesting that miR-3198 downregulates OPG in response to mechanical stress.