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ObjectivesTo compare a novel body mandibular horizontal plane (mental foramen–protuberance menti; Body-MHP) with the conventional border mandibular horizontal plane (gonion–menton [Me]; Border-MHP) to assess mandibular body inclination and dental compensation of skeletal Class III patients with and without facial asymmetry.Materials and MethodsRetrospective data obtained from diagnostic cone-beam computed tomography of 90 skeletal Class III patients (mean age, 21.67 ± 2.93 years; range, 15.0–30.6 years) were divided into symmetry (n = 30) and asymmetry groups (n = 60). The asymmetry group was subdivided into roll (n = 30) and non-roll types (n = 30). The differences in body inclination and dental measurements (distance and angle) according to two mandibular planes (Body-MHP and Border-MHP) were assessed in the groups and subgroups.ResultsMandibular body inclinations relative to the Body-MHP were not different in the roll-type asymmetric mandible between the sides, while those relative to the Border-MHP were different (P < .001). For the mandibular first molar positions relative to the Border-MHP, the differences in vertical distance between the sides were undermeasured and the inclination differences were overmeasured when compared relative to the Body-MHP.ConclusionsThe Body-MHP demonstrated better bilateral similarity in body inclination compared with the Border-MHP in patients with roll-type facial asymmetry. The novel body mandibular plane ensures an accurate diagnosis for tooth movement and jaw surgery, particularly in the roll-type asymmetric mandible.

This study aimed to evaluate maxillary skeletal and dental yaw in patients with skeletal Class III facial asymmetry and investigate its correlation with menton deviation.Initial cone-beam computed tomography data from 60 patients with skeletal Class III malocclusion were used. There were 30 patients in both the symmetrical group (menton deviation 2 mm) and the asymmetrical group (menton deviation 4 mm). After reconstruction of 3-dimensional (3D) cone-beam computed tomography data, maxillary yaw and 3D positions of skeletal and dental landmarks were measured and compared between the groups. After that, correlations between menton deviation and the other variables were assessed.No significant difference was noted in maxillary skeletal and dental yaw between the 2 groups. In the assessment of 3D positions, translation of the maxillary bone and maxillary dentition toward the menton deviation was observed (P 0.01). Maxillary skeletal and dental yaw was not significantly correlated with menton deviation in the asymmetrical group.Maxillary skeletal and dental yaw was not evident in either group. Therefore, when planning maxillary surgery for patients with skeletal Class III facial asymmetry malocclusion, it may be appropriate to shift the focus of decompensation from maxillary yaw to maxillary translation.

Recently, the demand for correcting facial asymmetry has been increasing, even when the extent of asymmetry is small. This case report describes nonsurgical orthodontic treatment for facial asymmetry in a 13-year-old female patient, facilitated by moving the deviant mandible to the nondeviated side after correcting for relevant dental compensation using microimplants. Mandibular repositioning was attempted using intermaxillary elastics between the microimplants placed into each jaw and guided by resin that was bonded on the maxillary first molar of the deviated side. To enhance mandibular movement, correction of the transverse occlusal cant and buccolingual inclination of the teeth were also performed. After 65 months of gradual treatment, facial symmetry, with favorable occlusion and jaw function, was achieved. These satisfactory results, including a well-balanced face and good occlusal interdigitation, were well maintained at the 53-month follow-up. Direct and functional forces applied against deviant functional forces can reduce facial asymmetry by differential growth or modeling of the condyle.

Idiopathic condylar resorption (ICR) is a rare, destructive temporomandibular joint disease characterised by progressive resorption of the condyles. This case report presents a record of an orthodontically treated patient with ICR with favourable posttreatment remodelling of the condyles. An 18-year-old woman sought treatment for ICR. A severe Class II high-angle facial pattern with resorption of bilateral condyles was evident. The treatment plan was determined after careful examination of condylar radiographs and comprised forward rotation of the mandible through full-arch intrusion with microimplants after extraction of the four premolars. The treatment was completed in 35 months, and the patient was noted to have a straight profile, good interdigitation and slightly increased condylar volume. Two years after retention, the condyles were stable, and the patient’s profile and occlusion remained acceptable despite a mild relapse of the mandibular position. ICR was successfully corrected with orthodontic treatment. Counter-clockwise mechanics applied during the ICR remission period not only improved facial aesthetics but were also suitable for condylar unloading.

The piezochromic fluorescence (FL) of a distyrylpyrazine derivative, 2,3-diisocyano-5,6-distyrylpyrazine (DSP), was investigated in this study. Depending on the recrystallization method, DSP afforded two different crystals with green and orange FL emission. The orange color FL emission crystal (O-form) was easily converted to the green color FL emission one (G-form) by manual grinding. The G-form was also converted to a slightly different orange color FL emission crystal (RO-form) by a weak UV irradiation. When the RO-form was ground again, the G-form was regenerated. The FL colors changed between the G- and RO-forms over several ten times by repeated mechanical grinding and UV irradiation. The FL, UV–visible, 1H-NMR and XRD results showed that the O (or RO)-to-G transformation induced by mechanical stress results from the change of degree of molecular stacking from dense molecular stacking structure to relatively loose molecular stacking structure, whereas the G-to-RO reconversion by UV irradiation results from return to dense molecular stacking structure again due to lattice movement (lattice slipping) allowed by photocycloaddition in solid-state.

Severe mandibular deficiency caused by temporomandibular joint (TMJ) ankyloses produces functional and aesthetic problems that require complicated long-term treatment. In this case report, we describe the benefits of using microimplant mechanics for controlling the direction of distraction during distraction osteogenesis and for performing the movement of teeth. We also present its remarkable results and long-term stability. A 20-year-old girl presented with a convex profile due to severe mandibular retrognathia after a history of several TMJ surgeries for bilateral TMJ ankyloses. Mandibular distraction osteogenesis (MDO) was performed, and elastics were placed between the microimplants to control the direction of distraction. Subsequently, after retraction of the maxillary anterior teeth and distalisation of the whole mandibular dentition, the facial profile was markedly improved, and good interdigitation was obtained. The six-year follow-up retention and overall stability were satisfactory with good interdigitation and jaw function.

To compare the removal torque of microimplants upon post-use removal and post-retention removal and to assess the influencing factors.The sample group included 241 patients (age, 30.25 ± 12.2 years) with 568 microimplants. They were divided into the post-use (microimplants removed immediately after use or treatment) and post-retention (microimplants removed during the retention period) removal groups. The removal torque in both groups was assessed according to sex, age, placement site and method, and microimplant size. Pearson correlation and multiple linear regression analyses were performed for evaluating variables influencing the removal torque.The mean period of total in-bone stay of microimplants in the postretention removal group (1,237 days) was approximately two times longer than that in the post-use removal group (656.28 days). The removal torques in the post-retention removal group (range, 4-5 N cm) were also higher than those in the post-use removal group. The mandible and pre-drilling groups demonstrated higher placement and removal torques than did the maxilla and no-drilling groups, respectively. In the no-drilling post-use removal group, the placement torque and microimplant length positively correlated with the removal torque. In the post-retention removal group, unloading in-bone stay period and microimplant diameter positively correlated with the removal torque in the no-drilling and pre-drilling methods, respectively.The removal torques differed according to the orthodontic loading and removal time of microimplants. With prolonged retention of microimplants inserted using the no-drilling method, the removal torque was clinically acceptable and positively correlated with the unloading in-bone stay period.

Background and Overview The authors describe a bracket-free forced eruption technique using microimplants that does not require patient compliance and report relapse after long-term observation. Case Description In 2 patients who needed to undergo forced eruption of carious and fractured roots of anterior teeth, the authors erupted the roots forcefully with a cantilever wire and microimplants as an anchorage. The microimplants provided sufficient anchorage by approximately 6 to 7 millimeters for forced eruption of the roots. The authors observed minor relapse of approximately 0.5 mm in both cases at the 1.5-year follow-up. Conclusions and Practical Implications The forced eruption method using microimplants and a sectional wire is simple and does not require patient compliance, but it does provide precise tooth movement. Clinicians can consider using long retention, overcorrection, and delayed cementation of prosthetic crowns to manage relapse.

SUMMARY: This study was performed to identify optimal microimplant sites in the mandibular retromolar area by measurement and analysis of cortical bone thickness and density. Forty-nine records of cone-beam computed tomography were selected from 173 patients. Invivo 5.2 software was used to measure the thickness and density of 25 sites on a mesh in the mandibular retromolar area. Pearson correlation, Spearman correlation, and binary logistic regression analyses were performed to explore correlations between retromolar measurements and patient characteristics. The LSD test was used to identify optimal microimplant sites in this area. One-way ANOVA, with post hoc SNK test, was used to compare optimal microimplant sites among the retromolar area, the distobuccal bone of the second molar, and a location between the first and second molars. The mean thickness and density of mandibular retromolar cortical bone were 2.35 ± 0.76 mm and 530.49 ± 188.83 HU, respectively. In the mandibular retromolar area, the thickness and density of cortical bone increased from the lingual to buccal sides, and from the distal to mesial. Among 25 sites, S5C1 had the greatest thickness and density; it exhibited greater thickness and density, compared with the distobuccal bone of the second molar and the site between the first and second molars. For distal uprighting of mesially tipped molars, we recommend placement of microimplants into the retromolar distobuccal site; for distalization of mandibular dentition, we recommend placement of microimplants into the retromolar mesiobuccal site (S5C1) or 2 mm from the mesial direction of the second molar distobuccal site (B).

In clinical orthodontic practice, fixed brackets are widely used for tooth movement and adjustments. Although years of research and development have improved the workability of fixed orthodontic brackets, there are still controversies regarding its plausible destructive influence on the enamel surface of tooth. This, in turn, makes the quantitative assessment of the enamel surface after specific orthodontic treatment procedures important in order to opt for the most effective treatment procedure. Through this study, we show the practical applicability of optical coherence tomography (OCT) as a non-ionizing and nondestructive assessment tool for measuring enamel loss after each step of orthodontic bracket bonding. Two-dimensional and volumetric OCT images are used for the evaluation of the tooth enamel. From the depth intensity profile analysis of cross-sectional OCT images, the changes in the individual internal layer thickness are calculated. A software algorithm was developed to evaluate the structural connectivity in the enamel for analyzing enamel loss on the tooth surface and for detecting enamel abrasion. An intensity-based layer segmentation algorithm is also developed to analyze and evaluate enamel wear in the tooth after each step. Using the proposed algorithms, the total enamel present after each treatment procedure was measured and tabulated for analysis.

Objectives: The study was done to evaluate the efficacy of optical coherence tomography (OCT), to detect and analyze the microdamage occurring around the microimplant immediately following its placement, and to compare the findings with micro-computed tomography (μCT) images of the samples to validate the result of the present study. Methods: Microimplants were inserted into bovine bone samples. Images of the samples were obtained using OCT and μCT. Visual comparisons of the images were made to evaluate whether anatomical details and microdamage induced by microimplant insertion were accurately revealed by OCT. Results: The surface of the cortical bone with its anatomical variations is visualized on the OCT images. Microdamage occurring on the surface of the cortical bone around the microimplant can be appreciated in OCT images. The resulting OCT images were compared with the μCT images. A high correlation regarding the visualization of individual microcracks was observed. The depth penetration of OCT is limited when compared to μCT. Conclusions: OCT in the present study was able to generate high-resolution images of the microdamage occurring around the microimplant. Image quality at the surface of the cortical bone is above par when compared with μCT imaging, because of the inherent high contrast and high-resolution quality of OCT systems. Improvements in the imaging depth and development of intraoral sensors are vital for developing a real-time imaging system and integrating the system into orthodontic practice.

A unique molecular rotor consisting of a tetraphenylethylene derivative with a paraffin wax-like long alkyl chain (TPE18) is synthesized and compared to other derivatives containing shorter alkyl chains. In differential scanning calorimetry, TPE18 shows an endothermic peak (enthalpy of fusion, ΔHfus = 55.3 J g−1) at 45 °C during the heating process and an exothermic peak at 38.6 °C during the cooling process. TPE18 exhibits critical changes in the fluorescence intensity and color during the crystal–melt phase change. TPE18 can be dissolved by an octadecane melt and then absorbed by filter paper. When the waxed paper is exposed to the heat sources of an IR laser or a finger, high-resolution fluorescence images of the characters and fingerprints appear on the paper. TPE18 also serves as a host matrix in a melt state that was easily mixed with the guest fluorophores of Alq3 and rubrene. Homogeneous hybrid solids with defined features are obtained without any significant segregation after cooling to room temperature. Fluorescence images with various colors are drawn onto the surfaces of glass slides or papers using the hybrids as crayons.

Objectives: To observe the surface characteristics and mechanical behavior of retrieved microimplants under clinically simulating experimental conditions and to investigate the feasibility of reuse of microimplants. Materials and methods: The microimplants, inserted at different angles, were retrieved from the patients (RMIP) and the artificial bone (RMIA). Surface characteristics, including morphologic changes of tips and thread edges, length reduction, and surface compositional variation, were evaluated using a field emission scanning electron microscope, a stereoscopic microscope, and energy-dispersive X-ray spectroscopy, respectively. Mechanical behavior comprising maximum insertion torque (MIT) and insertion time was tested with the artificial bone under clinically simulating conditions. Results: The tips and thread edges were worn out to various degrees in retrieved microimplants and thin deposits were observed on the surface in the RMIP group. Traces of foreign elements, such as iron, sulphur, and calcium, were detected on the surface of RMIP. Both MIT and insertion time of retrieved microimplants were increased compared to their initial use, and were much greater in RMIP. The increases of MIT were seen in all groups inserted at the insertion angle of 45° compared with 90°, although the differences were not statistically significant. Conclusions: Retrieved microimplants exhibited different degrees of changes on surface characteristics and mechanical behavior, with more changes in RMIP. The reuse of microimplants for immediate relocation in the same patient may be acceptable; however, postponed relocation and allogeneic reuse of microimplants are not recommended in clinical practice.

Selective photocyclic aromatization (SCAT) of cis–cisoid helical poly(phenylacetylene) derivatives was investigated during the in situ photodegradation in a film. An infrared absorption peak appeared at ∼1700 cm−1 owing to the overtone vibration of the 1,3,5-trisubstituted benzene and the peak at 1060 cm−1 due to the cis C=C bending of the main chain decreased, indicating occurrence of SCAT. Simultaneously, the polymer film became emissive in visible region during SCAT. The fluorescence (FL) quantum efficiency was approximately 0.92% in the film and not so much high relative to usual fluorophores. The FL emission disappeared in an instant when the decomposition product dissolved in a solvent. The FL lifetime of the polymer film increased with photodegradation. These all indicated the occurrence of excimer emission. A finely resolved FL image pattern was readily obtained using a photomask.

Introduction The aim of this study was to evaluate the distances from the maxillary posterior root apices to the inferior wall of the maxillary sinus using cone-beam computed tomography images and the relationships between roots and maxillary sinus according to age, sex, and skeletal pattern. Methods Three-dimensional images of each root were checked, and the distances were measured along the true vertical axis from the apex of the root to the sinus floor in 118 patients (63 male, 55 female) aged 10 to 28 years. Compare-means statistic tests were done to assess the differences between groups classified according to age, sex, and skeletal pattern. Results The frequency of root contact with the sinus floor increased from 70% at the second premolar to more than 80% at the buccal roots of the first and second molars. Male and older age (20-28 years) groups had significantly smaller distances or more protrusion of the root into the sinus than female and younger age (10-20 years) groups. The distances were shorter, or there was more protrusion of the root into the sinus in the hyperdivergent, down-canted palatal plane, and large gonial angle groups. Conclusions Male, older age, hyperdivergent skeletal pattern, and large gonial angle groups had significantly closer distances between maxillary root tips and the sinus floor or more protrusion of the roots into the sinus. The intrusion of the maxillary molars in those situations may be difficult and slow because of the pneumatized maxillary sinus.

A molecular rotor compound containing an allyl group (aMR) was synthesized and copolymerized with the vinyl monomers methyl methacrylate (MMA), styrene (St), and 2-hydroxyethyl methacrylate (HEMA). The absorption and fluorescence (FL) emission maxima of the solution of aMR in THF were observed at 445 and 485 nm, respectively. The FL quantum yield (FLQY) of aMR in THF was quite low (0.21%). However, it was found that the FL intensity significantly increased as the viscosity of the fluid increased. This change was expressed using the Forster-Hoffmann equation, log I = C + x log η, where I and η are the FL intensity of the probe and the viscosity of the fluid, respectively. The value of x was determined to be 0.66 and 0.53 for the methanol/ethylene glycol mixtures and alcohols, respectively. The absorption and FL emission spectra of the aMR-incorporated vinyl polymers were almost similar to those of aMR. The FLQYs of P(MMA-co-aMR), P(St-co-aMR), P(HEMA-co-MMA-co-aMR) films were 4.9, 4.3, and 5.1%, respectively. These FLQYs are ∼10 times of the values obtained with their solutions. As soon as the polymer film came into contact with the fluids, its FL emission started to decrease and reached an equilibrium state after a few minutes. It was found that the equilibrium FL emission became weaker as the viscosity of fluid decreased. The FL intensity ratio was also expressed using the modified Forster-Hoffmann equation. The x values of P(MMA-co-aMR) for alcohols and methanol/ethylene glycol mixtures, P(St-co-aMR) for hydrocarbons, and P(HEMA-co-MMA-co-aMR) for the methanol/ethylene glycol mixtures were 0.26, 0.24, 0.29, and 0.53 respectively.

A fluorescent conjugated polymer (FCP) and a photochromic dye (PD) were combined to investigate fluorescence (FL) switching through energy transfer between them. When the PD-dispersed FCP film was irradiated with UV light, no FL change was observed. However, when the film was wetted with paraffin oil, the FL emission was significantly attenuated by UV-light irradiation and subsequently restored by visible-light irradiation. Moreover, when the two materials FCP and PD were further mixed with an acryl oligomer made from n -butyl acrylate and a crosslinker, a well-featured solid film with a smooth surface was obtained after UV curing. Similar to the wet film, this three-component solid film showed a significant FL switching that was highly reversible and reproducible without any attenuation in the performance and appearance.

Objective To investigate the prevalence of malocclusion with respect to grade, sex, and year among Korean pre-adolescent and adolescent students during 2012–2017. Methods A total of 165,996 students (first grade [E1, 6–7 years of age], fourth grade [E4, 9–10 years], seventh grade [M1, 12–13 years], and tenth grade [H1, 15–16 years]) were selected by stratified sampling method and underwent the nationwide oral health examination performed by the Ministry of Education, Republic of Korea. The malocclusion assessments based on dentists’ judgments were “no malocclusion,” “needs orthodontic treatment (N-OTx),” and “under orthodontic treatment (U-OTx).” The sum of N-OTx and U-OTx cases was determined as the number of students with malocclusion. After analyzing the prevalence of malocclusion according to grade, sex, and year-by-year differences, Pearson correlation analyses and two-way analyses of variance were performed. Results The prevalence of malocclusion was 18.7%, which increased with the grades (E1 [8.3%] < E4 [15.8%] < M1 [22.9%] < H1 [25.3%], p < 0.001). However, there was no significant difference in the prevalence of malocclusion in each grade group for the period (p > 0.05) without significant correlation (E1, ρ = 0.129; E4, ρ = –0.495; M1, ρ = 0.406; H1, ρ = –0.383; all p > 0.05). The prevalence of malocclusion within each grade group over the six-year period was more prominent in the female (p < 0.0001). Conclusions Further studies are necessary to modify the malocclusion assessment method to account for specific types of malocclusion in pre-adolescent and adolescent students.

Introduction Insertion torque is the amount of torque exerted on the implant to tighten into the bone. We investigated whether insertion torque values could be correlated with the strain level in the peri-implant cortical bone resulting from mini-implant insertion. Methods The insertion of a standard size mini-implant (φ 1.4 mm × 7 mm) into maxillary alveolar bone was simulated using the finite element method. A total of 3600 calculation steps were employed to numerically reproduce the mini-implant insertion process and analyze the insertion torque and strain distribution in bone. Special attention was given to the relationship between insertion torque values and strain level in the cortical bone at the final tightening. The strain level was quantified using the following 3 strain parameters: (1) average insertion strain, (2) peak insertion strain recorded near the mini-implant thread tips, and (3) the size of the damage zone in the cortical bone. Correlations between the insertion torque values and these 3 parameters were analyzed using linear regression. Results Direct proportionality and strong correlation were found between the insertion torque values and each of the 3 strain parameters: average insertion strain (r2 = 0.91), peak insertion strain (r2 = 0.91), and the size of damage zone (r2 = 0.90) in the peri-implant cortical bone. Conclusions The results of this finite element method study demonstrated that insertion torque could serve as a reliable indicator of the strain level in the peri-implant cortical bone resulting from mini-implant insertion.

Microimplants are being used extensively in clinical practice to achieve absolute anchorage. Success of microimplant mainly depend on its primary stability onto the cortical bone surface and the associated Microdamage of the cortical bone during insertion procedure leads to many a microimplants to fail and dislodge from the cortical bone leading to its failure. Even though, previous studies showed occurrence of microdamage in the cortical bone, they were mainly 2-dimension studies or studies that were invasive to the host. In the present study, we used a non-invasive, non-ionizing imaging technique- Optical Coherence Tomography (OCT), to image and analyze the presence of microdamage along the cortical bone surrounding the microimplant. We inserted 80 microimplants in two different methods (drill and drill free method) and in two different angulations onto the cortical bone surface. Images were obtained in both 2D and 3D imaging modes. In the images, microdamage in form of microcracks on the cortical bone surface around the bone-microimplant interface and micro-elevations of the cortical bone in angulated microimplant insertions and the presence of bone debris due to screwing motion of the microimplant on insertion can be appreciated visually and quantitatively through the depth intensity profile analysis of the images.

Bonding of braces is an essential part in contemporary orthodontic treatment. For the proper strength of bracket bonding, enamel conditioning or surface treatment on tooth surface is required. Treatment on the tooth surface such as prophylaxis smoothing with pumice and enamel etching results in considerable damages to the enamel surface of the tooth. In this study, we have proposed optical coherence tomography as a noninvasive imaging technique for the evaluation of damage induced during such treatment procedures. Using depth intensity analysis of the obtained cross-sectional images, the damage resulting to the enamel surface was studied after prophylaxis smoothening and etching steps.

Bonding of braces is an essential part in contemporary orthodontic treatment. For the proper strength of bracket bonding, enamel conditioning or surface treatment on tooth surface is required. Treatment on the tooth surface such as prophylaxis smoothing with pumice and enamel etching results in considerable damages to the enamel surface of the tooth. In this study, we have proposed optical coherence tomography as a noninvasive imaging technique for the evaluation of damage induced during such treatment procedures. Using depth intensity analysis of the obtained cross-sectional images, the damage resulting to the enamel surface was studied after prophylaxis smoothening and etching steps.

SUMMARY: Cone Beam Computed Tomography (CBCT) measurement of cortical bone thickness and implantation angle in the maxillary posterior region was used to provide reference for the safety of Micro-Implanted-Anchorage (MIA) implantation in skeletal class II malocclusion. Twenty samples of CBCT images were collected from orthodontics patients (ages, 12-40 years) in Shanxi Medical University Stomatological Hospital, the thickness of cortical bone was measured at 45°, 60° and 90° from the alveolar crest, being at 4 mm, 6 mm and 8 mm, respectively. SPSS17.0 statistical software was used to analyze the data, and the one-way ANOVA and LSD method were compared. There was a significant difference in the thickness of the cortical bone obtained by implanting MIA at the same height of different angle (P≤0.05). The greater the inclination angle of the implanted MIA, the thicker the cortical bone. Also, the higher the implant site, the thicker the cortical bone thickness. Finally, the greater the thickness of the cortical bone in the maxillary posterior region of skeletal class II malocclusion, the greater the thickness of the cortical bone. At the same implantation height, implanted MIA with a tilt angle of 45º to 60º, 90º to obtain the best cortical bone thickness.

The purpose of this research was to evaluate dental compensation in facial asymmetry and its correlation with skeletal variables using cone-beam computed tomography.Sixty adult patients were retrospectively divided into asymmetry (mean age, 21.8 ± 5.4 years) and symmetry groups (mean age, 28.1 ± 4.1 years); both groups comprised 30 patients. Independent and paired t tests were used for comparisons between the asymmetry and symmetry groups and between deviated (Dv) and nondeviated (NDv) sides of the asymmetry group, respectively. Pearson correlation between dental and skeletal variables was performed.The mean value of menton deviation was 9.4 mm in the asymmetry group. Compared with the symmetry group, the direction and amount of dental compensation of the asymmetry group were as follows: 2.5-mm extrusion of the maxillary first molar (UM6) at NDv (P 0.05); 1.8-mm higher position of the mandibular canine (LC) from the mandibular horizontal plane using mental foramen (MHP_mf) at NDv (P 0.05); 6°-more buccoversion of UM6 at Dv; 3.7°-more linguoversion of UM6 at NDv; 4.8°-more buccoversion of the maxillary canine (UC) at Dv; 4.9°-more buccoversion of the mandibular molar (LM6) at NDv; and 2.6°-more linguoversion of LC at Dv. Dental compensation correlated or marginally correlated with skeletal variables of the deviated mandible.Dental compensations, extrusion of the maxillary molars on the NDv, and buccal tipping of the maxillary teeth and lingual tipping of the mandibular teeth on the Dv, were observed. The mandibular body length was associated with linguoversion of the mandibular molars on the Dv. The ramal inclination was related to the extrusion of the maxillary molars on the NDv.

Liquefied natural gas (LNG) terminals, one of the lifeline facilities, need to be protected by a proper seismic design against extreme earthquakes. An LNG terminal consists of a series of process facilities that are connected by pipelines of various sizes. Boil-off gas (BOG) compressor is one of the critical process facilities whose failure will cause the functional failure of the LNG terminal. Process facilities, including BOG compressor, other than LNG storage tanks and pipes, have not been a major concern in terms of the seismic performance evaluation. In this study, the seismic performance of a BOG compressor is evaluated and the seismic fragility functions are presented. An integrated system of a BOG compressor is modeled by a 3 dimensional finite element modeling scheme. A series of time history analyses are conducted to monitor the behavior of anchor bolts, one of the most critical elements in the BOG compressor. To develop fragility curves, a set of 20 ground motions are selected from a database of the historic earthquake accelerations. Fragility curves are developed based on the maximum likelihood estimation approach with respect to the strength limit states. When an earthquake load is applied to the BOG compressor, the main motor is likely to overturn and the flywheel is likely to slide, and, consequently, anchor bolts will be subjected to tension and shear force, respectively. It is concluded that the BOG compressor is safe against the design level earthquake

Objective: To analyze the influence of the length of temporary intraoral skeletal anchorage devices (TISAD/TAD) on their long-term stability in the mandible in a homogenous group of patients. Materials and Methods: A group of generally healthy patients of the same gender (female) and with a statistically insignificant age difference (20–29 years) highly homogenous with respect to known factors affecting the success rate of TISAD/TAD was evaluated. One type of TISAD/TAD was applied (6- or 8-mm long). Each patient received both 6- and 8-mm-long TISAD/TAD in randomly selected mandibular quadrants: left or right. The long-term success rate of TISAD/TAD was analyzed. Results: The 8-mm orthodontic mini-screw implants were significantly more stable than the 6-mm ones in the analyzed group. Conclusion: The length of the TISAD/TAD may be one of the factors that can affect the long-term success rate in the mandibles of 20- to 29-year-old women.