bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection and attribution of the spatiotemporal trend of climatic disaster impacts and vulnerability in Nepal
Authors: Chapagain Dipesh , Bharati Luna , Borgemeister Christian
Published: September 2021

The impacts of climatic disasters have been rising globally. Several studies argue that this upward trend is due to rapid growth in the population and wealth exposed to disasters. Others argue that rising extreme weather events due to anthropogenic climate change are responsible for the increase. Hence, the causes of the increase in disaster impacts remain elusive. Disaster impacts are higher in low-income countries, but existing studies are mostly from developed countries or at the cross-country level. Here we assess the spatiotemporal trends of climatic disaster impacts and vulnerability and their attribution to climatic and socioeconomic factors at the subnational scale in a low-income country, using Nepal as a case study. Loss of life is the most extreme consequence of disasters. Therefore, we employed human mortality as a measure of disaster impacts, and mortality normalized by exposed population as a measure of human vulnerability. We found that climatic disaster frequency and mortality increased in Nepal from 1991 to 2020. However, vulnerability decreased, most likely due to economic growth and progress in disaster risk reduction and climate change adaptation. Disaster mortality is positively correlated with disaster frequency and negatively correlated with per capita income but is not correlated with exposed population. Hence, population growth may not have caused the rise in disaster mortality in Nepal. The strong rise in disaster incidence, potentially due to climate change, has overcome the effect of decreasing vulnerability and caused the rise in disaster mortality.
Phylogenetic Relationship Between the Endosymbiont “candidatus Riesia Pediculicola” and Its Human Lice Host
Authors: hammoud alissa , Louni Meriem , Missé Dorothée , Fenollar Florence , Mediannikov Oleg
Published: September 2021

Background: The human louse is one of the most ancient haematophagous ectoparasites that is related intimately to its host and has been of great concern to public health throughout human history. Previously, Pediculus humanus was classified within six divergent mitochondrial clades (A, D, B, F, C and E). Like all haematophagous lice, P. humanus directly depends on the presence of bacterial symbionts, known as “Candidatus Riesia pediculicola”, to complement their unbalanced diet. In this study, we evaluated the coevolution of human lice around the world and their endosymbiotic bacteria. Using molecular approaches, we targeted lice mitochondrial genes from the six diverged clades and Candidatus R. pediculicola housekeeping genes. Methods: A total of 126 lice were selected for molecular analysis of the cytb gene for lice clade determination. In parallel, four PCR primer pairs were developed targeting three housekeeping genes of Candidatus R. pediculicola: ftsZ, groEL and two regions of the rpoB gene (rpoB-1 and rpoB-2).Results: The endosymbiont phylogeny perfectly mirrored the host insect phylogeny, using the ftsZ and rpoB-2 genes, suggesting a strict vertical transmission and a host-symbiont co-speciation following the evolutionary course of the human louse. Conclusion: Our results unequivocally indicate that lice endosymbiont have experienced a similar co-evolutionary history, and that the human louse clade can be determined by their endosymbiotic bacteria.
Nintedanib reduces corticosteroid resistance pulmonary fibrosis induced by bleomycin in mice by increasing the expression of β3 & β6 integrins
Authors: Alghamdi Doha O , Kawy Hala S Abdel , Damanhouri Zuhair A
Published: September 2021

Background:Corticosteroid resistance pulmonary fibrosis is a major health problem. This study aimed to determine the effectiveness of nintedanib on corticosteroid resistance pulmonary fibrosis induced by bleomycin in mice.Methods:The mice were divided into five groups 12 mice each. control group, BLM group received single dose of bleomycin (BLM), BLM+MP group received BLM and methylprednisolone (MP), BLM+NIN group received BLM and nintedanib(NIN) and BLM + NIN + MP group. The lung tissues were obtained for biochemical analysis, gene expression and histopathological examination on day 7 and day 28.Results:After 7 days, both NIN groups showed a significant decrease in the levels of interleukin-2, interleukin-4, interferon-gamma, lung tumor necrosis factor-alpha, Malondialdehyde and lung water content with a significant increase in the Glutathione level in lung tissues compared to MP group. After 28 days, both NIN groups showed a significant reduction in hydroxyproline, and Trans-forming Growth Factor beta lung tissues contents compared to MP group, and they showed a positive effect on the expression of β 3 &β6 integrins compared to the negative effect of MP group. Histopathologically, both NIN groups showed significant improvement compared to MP group by H&E and Masson’s trichrome stains. Immunohistochemical staining revealed negative BCL-2 expression in the cytoplasm of bronchiolar epithelium in both NIN groups after 7 and 28 days of treatment. Lung tissue morphometric studies showed significant improvement of pathological changes induced by BLM in both NIN groups.Conclusion:Altogether, our data indicates that nintedanib overcame corticosteroid resistance pulmonary fibrosis induced by bleomycin.
Alcohol use and misuse among school adolescents from national surveys in Saint Lucia and Saint Vincent and the Grenadines in 2018
Authors: Peltzer Karl , Pengpid Supa
Published: September 2021

The study aimed to estimate the prevalence of alcohol use and misuse and associated factors among adolescents in Saint Lucia and Saint Vincent and the Grenadines. Data from 3,847 adolescents (mean age:14.6 years, SD = 1.7) that took part in national cross-sectional school surveys in 2018 in Saint Lucia, and Saint Vincent and the Grenadines were analysed. Students responded in a classroom setting to self-administered questions on substance use and othe variables. The results indicate that 42.7% of the students reported current alcohol use, 27.9% were ever drunk and 11.4% had trouble with alcohol use. In adjusted logistic regression analyses, compared to students from Saint Lucia, students from Saint Vincent and the Granadines had higher odds of trouble from drinking. Older age was associated with current alcohol use and ever drunk but not with trouble from drinking. Severe food insecurity and suicidal ideation were associated with trouble from alcohol use. Current tobacco use and current cannabis use were highly associated with current alcohol use, ever drunk, and trouble with alcohol use, while ever use of amphetamines was associated with ever drunk. School truancy, participation in physical fights, injury, and multiple sexual partners increased the odds, while parental support decreased the odds of current alcohol use, ever drunk, and trouble from alcohol use. In conclusion, high alcohol use and misuse has been identified calling for interventions.
Integrated reporting and firms' performance of listed ICT companies in Nigeria
Authors: Kaura Aminu Abdullahi , Bello Abdulrasheed , Sokoto Sirajo Sani
Published: September 2021

The purpose of this study is to examine the effect of corporate performance of 9 listed ICT companies in Nigeria over a period of ten years (2011 – 2020). MVA and ROA were employed as market and financial based measures of performance and controlling for Leverage, Firm size and Age. Panel regression was employed using fixed effect model to test the study hypothesis. The findings from the analysis revealed a positive and significant association between IRINDEX and MVA while the result was insignificant between ROA and IRINDEX. All the control variables were significantly associated with IRINDEX. The model was also significant with f-statistics probability significant at 1% (0.000) level. The model account for about 66.21% variation in IRINDEX. The study therefore concluded that, corporate performance affect IR only in the long-run. The study recommended that, regulatory agencies in Nigeria should enact laws that make it mandatory for quoted companies to adopt IR or grant tax credit to voluntary compliers and lastly, managers should strive to adopt IR not minding its cost implication in the short-run as the benefit will accrue in the long-run.
Yield and Quality of Carrot Cultivars with Eight Nitrogen Rates and Best Management Practices
Authors: Hochmuth Robert Conway , Burani-Arouca Marina , Barrett Charles Edward
Published: September 2021

Carrot (Daucus carota) production has increased in North Florida and South Georgia since 2015. Deep sandy soils, moderate winter climate, availability of irrigation water, and proximity to eastern markets are favorable for carrot production in the region. Nitrogen (N) is required for successful carrot production, and the current recommended N application rate in Florida is 196 kg·ha−1. The objective of this study was to verify the recommended N rate for the sandy soils of North Florida using current industry standard cultivars and practices. Carrot cultivars for the whole carrot fresh market, Choctaw and Maverick, and cultivars for the cut-and-peel market, Triton and Uppercut 25, were direct seeded on 102-cm-wide pressed bed tops on 29 Oct. 2016 and 2 Nov. 2017 in Live Oak, FL. Eight N application rates (56, 112, 168, 224, 280, 336, 392, and 448 kg·ha−1) were tested, and all N applications were placed on the bed top. N rates were split and timed to increase N use efficiency. Regression analyses were used to determine the optimal N rate for carrots in North Florida. A quadratic plateau regression for both seasons combined indicated 206 kg·ha−1 N was the optimal rate for carrots, with marketable yield of 71.3 Mg·ha−1, regardless of cultivar. All four cultivars attained acceptable yield including Uppercut 25, which exhibited significant foliage damage following freezing temperatures. This study resulted in updated information on best management practices for carrot production in Florida, especially nutrient stewardship.
Branching Response of Poinsettia ‘Orange Spice’ to a Combination of Pinching, No Pinching, and Atrimmec
Authors: Dunn Bruce L. , Stanphill Stephen , Goad Carla
Published: September 2021

This study aimed to identify the best method to improve poor branching of poinsettia ‘Orange Spice’. Treatments included pinched and unpinched alone and in combination with four different rates (3.9, 7.8, 11.7, and 23.4 mL⋅L−1) of Atrimmec. Pinching reduced plant height, as did unpinched + 11.7 mL⋅L−1 and unpinched + 11.7 mL⋅L−1 Atrimmec. Neither pinching nor Atrimmec had any effect on plant width, stem caliper, or shoot dry weight. Atrimmec did not increase the number of laterals in combination for pinched or unpinched treatments, but unpinched plants generally produced more laterals. Unpinched with any rate of Atrimmec resulted in tertiary shoots, which improved the visual appearance and quality.
Modeling of natural convection of a concentrated solar power receiver absorber tube in interaction with neighbouring absorbers
Authors: Oyewola Olanrewaju Miracle , Olukayode Niyi Ezekiel , Ajide Olusegun Olufemi
Published: September 2021

Concentrated Solar Power (CSP) technology stands out among other renewable energy sources not only because of its ability to address current energy security and environmental challenges but because its energy can be stored for future use. To ensure optimum performance in this system, the heat losses need to be evaluated for better design.

This work studies the natural convection in the receiver absorber tube of a CSP plant taking into consideration the influence of neighboring absorbers. A 2-Dimensional model was adopted in this study. Initially, a single absorber tube was considered, it was subjected to heat flux at the top wall, the bottom wall was insulated and a temperature differential was set up at the lateral walls. The dimensionless forms of Navier-Stokes and energy equations were solved using the finite element formulation of COMSOL Multiphysics software. The result obtained for a single absorber tube showed good agreement with existing research works. This validated model was then extended to multiple absorber tubes (two to six absorber tubes). On the basis of the study, there is an observed increase in the intensity and dominance of convective heat transfer with an increase in the number of absorber tubes. This is occasioned by an increase in the average surface temperature as well as average Nusselt number. For the Rayleigh number of 104, 105 and 106, the average Nusselt number increases with the number of absorber tubes by 13.87 %, 6.26 %, and 1.55 %, respectively. This increment suggests effect of thermal interactions among the neighboring absorber tubes
Comparison of chewing gum and ibuprofen in alleviating orthodontic pain: a single centre, randomised clinical trial
Authors: Delavarian Mohadeseh , Imani Mohammad Moslem , Delavarian Fatemeh , Bayani Shahin
Published: September 2021

Background

The aim of the present three-arm parallel trial was to compare the effectiveness of chewing gum and ibuprofen in the control of orthodontic pain.

Methods

Patients to undergo orthodontic treatment at a private orthodontic clinic were randomly divided into three parallel groups, each of which took either a placebo, ibuprofen or chewing gum. The eligibility criteria included patients in the full permanent dentition with moderate crowding requiring the extraction of two mandibular and two maxillary premolars. The main outcome was the patient’s level of discomfort, which was assessed by a 0–10 numeric rating scale (NRS) at two hours, six hours, at bedtime, 24 hours, two days, three days and seven days after the placement of initial arch wires in four functions including chewing, biting, occluding back teeth, and occluding front teeth. Randomisation was accomplished according to the patient’s clinic entrance number and by using a table of random numbers. The patients in the placebo and ibuprofen groups were blinded to the type of medication used. The differences in the groups were analysed using repeated measures ANOVA.

Results

Sixty-six patients between 12 and 30 years were randomised in a 1:1:1 ratio. The pain questionnaire response rate was 100% in the three groups, but six patients were excluded and consequently 60 patients were analysed (N = 20 in each group). There was no significant difference between the chewing gum and ibuprofen groups during any oral function at any time point (p > 0.05). However, repeated measures ANOVA showed that patients in the placebo group experienced significantly higher pain scores compared with patients in the ibuprofen and chewing gum groups at two hours, six hours, at bedtime, at 24 hours and two days after initial arch wire placement (p < 0.05). No patient harm was observed in this study.

Conclusions

In contrast to the common orthodontic belief that gum chewing may lead to bracket breakage, it seems that chewing gum is as beneficial as medication for pain relief and can be a recommended alternative during orthodontic treatment.
Impacted maxillary canines and their relationship with lateral incisor resorption: a cone beam computed tomography (CBCT) study
Authors: Yilmaz Hakan , Ozlu Fethiye Cakmak , Icen Murat , Icen Erdi
Published: September 2021

Objective

The spatial position of a canine can affect the level of proximal root resorption and the success of orthodontic treatment. The aim of this study was to examine the mesiodistal and vertical position of impacted maxillary canines and to assess their relationship with the lateral incisor by using cone beam computed tomography (CBCT).

Material and method

One hundred and sixty-nine CBCT scans of patients presenting with maxillary impacted canines were included in the study. The buccopalatal, mesiodistal (classified as sectors I, II, III, IV from distal to mesial) and vertical (cervical, middle, apical) position of the maxillary impacted canines were determined. The positional effect on the morphology (width, length, and depth) and resorption was assessed on the roots of the maxillary lateral incisors. Obtained data were statistically analysed by using Student t-test, the Mann Whitney U and Chi-Square tests.

Results

Of the maxillary impacted canines, the 34.72% that had associated resorption on the adjacent lateral incisors were buccally positioned, and 65.28% were palatally positioned. While 45.58% of sector I impacted maxillary canines were buccally positioned, 68.31% of sector IV impacted maxillary canines were palatally positioned. Furthermore, there was a statistical significance between the mesiodistal position and palatal or buccal maxillary canine impaction (p < 0.05). In addition, the vertical position of the impacted maxillary canines was also related to their mesiodistal and buccopalatal positions (p < 0.05).

Conclusion

While all maxillary impacted canines had the potential to cause lateral incisor resorption, there was no close relationship related to the canine’s buccopalatal, mesiodistal and vertical position. Nevertheless, if an impacted maxillary canine migrated towards the midline, the buccopalatal and vertical position of the tooth changed from buccal to palatal and cervical to apical, respectively.
Local orthodontic force initiates widespread remodelling of the maxillary alveolar bone
Authors: Gong Xinyi , Huang Xiangru , Yang Yiling , Zhou Siru , Dai Qinggang , Jiang Lingyong
Published: September 2021

Objectives

To clarify the effects of a local orthodontic force on alveolar bone by analysing bone remodelling in different regions of the maxilla during orthodontic tooth movement (OTM).

Methods

An OTM model was established in rats. Histological changes in the maxilla were analysed using TRAP staining, IHC staining for CTSK and haematoxylin and eosin (H and E) staining. The root bifurcation region of the alveolar bone of the first (M1), second (M2) and third (M3) molars were selected as the regions of interest (ROIs), which were further divided into a cervical and an apical level. Sequential fluorochrome labelling was performed to analyse bone deposition rates.

Results

The maxillary left first molars were moved mesially. TRAP staining and IHC staining for CTSK showed orthodontic force increased osteoclast numbers in all six ROIs at both the cervical and apical levels. H and E staining indicated elevated osteoblast numbers in the OTM group in all induced regions. Sequential fluorochrome labelling exhibited increased bone deposition rates around M1, M2 and M3 in the OTM group.

Conclusions

An orthodontic force applied to the first molar could initiate widespread remodelling of the maxillary alveolar bone, which was not restricted to the tension and pressure sites. This may revise the orthodontic biomechanical theory and provide new insights for clinical work.
Treatment of anterior open-bite using zygomatic anchorage: a 10-year follow-up case report
Authors: Uslu-Akcam Ozge , Efendiyeva Ruhengiz , Akcam Mehmet Okan
Published: September 2021

Aim

To present the treatment and long-term post-treatment results of an adult case presenting with an Angle Class II anterior openbite malocclusion that involved the use of zygomatic anchorage for the intrusion of the maxillary posterior teeth.

Methods

A 23-year-old female patient with a bilateral Angle Class II molar and canine relationship, a 4 mm overjet and a 6 mm anterior open-bite was treated using zygomatic anchorage in order to correct the dental and skeletal relationships, and eliminate the anterior open-bite to achieve an ideal overjet, overbite and improved facial aesthetics. Orthodontic brackets were placed on the maxillary and mandibular teeth. Under local anaesthesia, a subperiosteal flap was raised, and two titanium miniplates were bilaterally placed in the zygomatic area. The molars were intruded by applying 400 grams of force to the miniplates via connection to the upper arch wire.

Results

By intruding the molar teeth using zygomatic anchorage, the anterior open-bite was corrected to achieve an Angle Class I occlusion, an ideal overbite and a harmonious facial profile that were successfully maintained after a 10-year follow-up period.
Reducing iatrogenic complications in the treatment of cleft lip and palate
Authors: Savundra Andrew , Fricker John
Published: September 2021

All patients receiving orthodontic treatment with fixed appliances have a significantly higher risk of developing white spot lesions (WSLs), which are considered the most common iatrogenic complication of treatment.

Cleft lip and/or palate (CLP) is a common craniofacial anomaly occurring in approximately one in 800 births. Patients affected by cleft lip and/or palate tend to have poorer oral hygiene and a greater risk of WSLs and caries than non-cleft sibling controls. Patients presenting with a cleft lip and/or palate also have a higher prevalence of molar-incisor hypomineralisation (MIH), which suggests that clinicians involved in the oral health management of cleft patients need to consider all available caries prevention protocols.

Cases presenting with hypomineralised teeth create more difficulty in bonding attachments to affected enamel using an acid etch technique and a composite resin material due to the abnormal prism structure. The bond strength to hypomineralised enamel can be as low as two-thirds that of the bond strength to unaffected enamel, which may not be adequate for routine fixed appliance treatment. Furthermore, the removal of orthodontic brackets from hypomineralised enamel may lead to more severe damage to the affected teeth.

Resin modified glass-ionomer cement (RMGIC), bonded after conditioning the enamel with polyacrylic acid, creates no resin tags as a result of a chemical rather than a mechanical bond. Therefore, there is less enamel loss during bracket debonding when compared with acid-etch preparation and composite resin bonding.

Furthermore, in cases in which the quality of the enamel is deficient causing limits to the shear bond strength of the acid-etched composite resin, the chemical bonding action of RMGIC overcomes the lack of adherence and protects the enamel.

RMGIC has cariostatic properties and clinical evidence supports the routine use of these adhesives for bonding in all fixed appliance cases as a strategy for reducing the incidence of white spot lesions and damage to the enamel during bracket debonding.
The effect of head posture on facial soft tissue changes captured by white-light facial scanning
Authors: Lim Jae-Beom , Oh Seung-Wook , An Hyun-joon , Park Tae-Joon , Lee Tae-Hee , Park Ki-Ho
Published: September 2021

Objective

To investigate whether changes in head posture have significant effects on facial soft tissues during white-light scanning.

Materials and methods

Thirty-four adult patients participated in the study in which 22 soft tissue landmarks were marked on the face of each subject using an oil-based pen. The subjects wore digital inclinometers on top of their heads, and sat relaxed with their heads orientated in natural head position (NHP), while a facial scan was captured. The subjects underwent a second facial scan in an upward 5°(U5), upward 10°(U10), downward 5°(D5), or a downward 10°(D10) direction with respect to the NHP. The NHP image was superimposed on the images taken at the different head postures and a single co-ordinate system was obtained. The axial reference plane (x-axis), the sagittal reference plane (y-axis) and the coronal plane (z-axis) were set with N’ as the zero point (0, 0, 0). The changes in position of each landmark caused by the change of head posture were measured.

Results

When the subject’s head was in the U5 and D5 posture, changes in landmark identification were not statistically significantly different. When the subject’s head was in the U10 posture, soft tissue Stmi and Li moved downward significantly. Soft tissue pogonion moved forward significantly in the D10 posture.

Conclusions

Soft tissue changes within 5° of the natural head posture were clinically negligible. If efforts to reproduce natural head position are carried out, reliable facial scanning images can be obtained without the support of any special head positioning tools.
Retreatment of a skeletal Class II postpubescent patient with a convex facial profile and temporomandibular disorders
Authors: Zhang Jia-Nan , Chen Si , Zhong Chong , Yu Feng-Yang , Lu Hai-Ping
Published: September 2021

Objectives

The present case report describes the orthodontic retreatment of a skeletal Class II postpubescent female patient who presented following previous orthodontic treatment that involved the extraction of the four first premolars, temporomandibular disorders and a convex facial profile.

Methods

The patient, aged 15 years, sought treatment for the chief complaints of an unaesthetic facial profile and difficulty in opening her mouth. The examination revealed a convex facial profile and a moderate skeletal Class II relationship within a long face. The patient had bilateral pain around the temporomandibular joints and her maximum mouth opening was only 11 mm. The treatment plan was to initially relieve the temporomandibular symptoms and then to retract the upper dentition using miniimplants.

Results

The patient’s mouth opening ability reached 37 mm and a significantly improved harmonious facial profile was achieved.

Conclusions

Cases that present with previous unsuccessful orthodontic treatment may be retreated to achieve a satisfactory aesthetic and functional result by precise control of tooth movement in three dimensions.
Accuracy of orthognathic surgery using 3D computer-assisted surgical simulation
Authors: Lee Richard , Goonewardene Mithran S , Mian Ajmal , Allan Brent , Brock Danny , Trevenen Michelle
Published: September 2021

Objective

To evaluate the accuracy of maxilla and mandibular repositioning during two-jaw orthognathic surgery using computerassisted
surgical simulation (CASS)

Materials and methods

Fifteen patients who underwent two-jaw orthognathic surgery using CASS (VSP,® Orthognathics by 3D Systems) were evaluated to assess the accuracy of the simulation. Translational and rotational discrepancies of the centroids of the maxilla and mandible and the translational discrepancy of the dental midline between the planned and actual outcomes were reported using the root mean square error (RMSE). The number of cases that exceeded limits set for clinical significance, the direction of the error in relation to the direction of planned movement and the differences between segmental and non-segmental procedures were evaluated as secondary outcomes

Results

The largest translational RMSE was 1.53 mm along the y-axis in the maxilla and 1.34 mm along the y-axis in the mandible. The largest rotational RMSE was 1.9° about the x-axis in the maxilla and 1.16° about the x- and y-axes in the mandible. The largest RMSE for the dental midline was 1.6 mm along the y-axis in the maxilla and 1.34 mm along the y-axis in the mandible. A tendency for insufficient advancement of the maxilla was noted

Conclusions

CASS is an efficient and accurate way to develop the surgical plan and transfer the plan to the patient intraoperatively. While CASS is accurate on a population level, there remains the potential for clinically significant errors to occur on an individual basis

Conclusion

The present case indicated that the timely extraction of palatally-placed maxillary lateral incisors facilitated functional appliance therapy in the management of a skeletal Class II problem. The crowding of the lower anterior teeth was relieved and alignment of the upper arch was achieved with full fixed appliance therapy, resulting in improved aesthetics and a stable occlusion at one year review
Multidisciplinary treatment of a severe facial asymmetry
Authors: Atik Ezgi , Konas Ersoy , Kocadereli Ilken
Published: September 2021

This case report presents the multidisciplinary treatment of an adult female who presented with a previously repaired right unilateral cleft lip and palate. The patient had been referred with a complaint of facial asymmetry, eating difficulties and a missing right central incisor. A clinical evaluation revealed severe facial asymmetry created by a mandibular deviation to the right side and a compensatory transverse cant of the maxillary occlusal plane. After pre-surgical orthodontic treatment, a Le Fort I osteotomy and a bilateral sagittal split osteotomy were performed. During post-surgical orthodontic treatment and, as a result of the rotational surgery, the maxillary left central incisor became the right central incisor. The left lateral incisor was subsequently moved toward the midline and reshaped with a composite buildup to serve as a new left central incisor. The combination of orthodontic, orthognathic and restorative treatment established a favourable occlusal and aesthetic result.
Management of multiple adjacent asymmetric intruded teeth by differential curve of Spee mechanics: a case report
Authors: Chang Heng-Ming Mark , Ting Chao-Wen , Wang Kai-Lung , Ho Kwok-Hing , Hsieh Shun-Chu , Lin Hsueh-Jen
Published: September 2021

Introduction

Of the types of dental trauma, intrusive luxation is considered to have the worst prognosis. When forceful intrusion affects multiple adjacent teeth, orthodontic repositioning may be required; however, orthodontic treatment can be complicated by the development of a cant in the occlusal plane, especially when the affected teeth are not symmetrically located from the midline and corrective forces and anchorage are unbalanced. Designing an appropriate mechanism to overcome this problem is essential.

Case presentation

The present case report describes a 28-year-old male who suffered the traumatic intrusion of multiple teeth, with accompanying alveolar bone fractures, following a road traffic accident. The intruded teeth were repositioned using orthodontic traction, following which, endodontic treatment was performed. After initial alignment, differential curve of Spee mechanics were applied to correct the occlusal plane and an acceptable result was achieved. The overall outcome was maintained at a 24-months review.

Conclusion

This report demonstrates the importance of the early repositioning of intruded teeth to avoid dento-alveolar ankylosis, as well as the use of differential curve of Spee mechanics which provides effective force application in the management of a canted occlusal plane.
Long-term evaluation of enamel colour change following orthodontic treatment: a randomised clinical trial
Authors: Pandian Akshaya , Jagdish Nithya , Kailasam Vignesh , Padmanabhan Sridevi
Published: September 2021

Objective

To evaluate enamel colour change over a period of one year after the completion of fixed appliance treatment and to assess the influence of two different clean-up procedures and the resulting surface roughness.

Materials and methods

Seventeen orthodontic patients were debonded and the residual resin removed using tungsten carbide burs followed by enamel polishing with Stainbuster burs or Sof-Lex discs in a split mouth design. A spectrophotometric colour evaluation was performed after clean-up (T0), polishing (T1), and one year later (T2). Colour parameters were measured and enamel colour change (ΔE) was calculated. Surface roughness was determined at T1 and T2 using epoxy replicas. Data were analysed using paired and unpaired t-tests and Pearson’s correlation.

Results

Significant differences in colour change and surface roughness caused by the polishing techniques at T1 were observed. However, this difference was not evident at T2 (p < 0.05). Surface roughness and colour change showed no significant correlation.

Conclusion

Enamel colour changed significantly when evaluated at T2 (one year post-orthodontic treatment). Stainbuster burs resulted in brighter and smoother teeth immediately after orthodontic treatment. The colour and surface roughness were not significantly different after one year and had no significant correlation.
Long-term surgical-orthodontic management of hemimandibular hyperplasia
Authors: Bennett Samuel C. , Goonewardene Mithran S.
Published: September 2021

Background

Hemimandibular hyperplasia (HH), also known as hemimandibular hypertrophy, is characterised by excessive unilateral three-dimensional growth of the mandible after birth. Vertical unilateral elongation of the mandible becomes clinically evident as a rare form of vertical facial asymmetry. Aberrant growth of the facial skeleton affects the developing dentition and the dental compensatory mechanism is usually unable to maintain optimal occlusal relationships. The resulting malocclusion is effectively managed by combined surgical-orthodontic care to address the facial, skeletal and dental problems that confront clinicians. Orthodontists are advised to assess patients with HH during the post-treatment retention stage for continuing mandibular growth and assess the stability of treatment outcomes with long-term follow-up and records as required.

Aim

To present a case of hemimandibular hyperplasia treated successfully by combined surgical-orthodontic care and evaluated for stability over a seven-year follow-up period.

Methods

Surgical-orthodontic management was accomplished in four stages: 1) pre-surgical orthodontic; 2) surgical; 3) post-surgical orthodontic; and 4) post-treatment orthodontic retention. Complete orthodontic records, including extra- and intra-oral photographs, study models, and cephalograms plus panoramic radiographs were taken at the pretreatment, post-treatment, and seven-year orthodontic retention time-points.

Results

Facial, skeletal and dental goals were achieved in the three planes of space and the long-term stability of the treatment results was shown during a post-treatment orthodontic retention period of seven years.

Conclusion

Hemimandibular hyperplasia is a true growth anomaly which may be managed effectively. Clinicians may expect successful long-term correction and stability by utilising a comprehensive surgical-orthodontic treatment approach.
A qualitative study of orthodontic screening and referral practices among dental therapists in New Zealand
Authors: Tan Allan , Bennani Florence , Thomson W. Murray , Farella Mauro , Mei Li
Published: September 2021

Background

Appropriate screening and referral is important in delivering effective and timely orthodontic treatment. In New Zealand, dental therapists are usually the initial contact for oral health care (including the assessment of malocclusion) in child and adolescent patients.

Objective

To investigate the orthodontic screening and referral practices of dental therapists in New Zealand.

Methods

Ten registered dental therapists from Auckland and Dunedin were interviewed using a semi-structured approach. Participants were selected based on years of work experience, where they practised, their educational background, and their sector of work (private/public).

Results

Three main themes were identified: (1) the orthodontic screening and referral process; (2) the factors affecting orthodontic referral; and (3) their attitudes towards orthodontic treatment. Orthodontic screening and referrals were uniform among public dental therapists but varied for private dental therapists with regard to the type of malocclusions referred, the frequency of the referrals and to whom they referred. Factors that affected orthodontic referrals included participants’ orthodontic educational background, work experience, Continuing Professional Development courses attended, and the opinions of orthodontists and/ or dentists. Dental therapists found that most patients were receptive to the idea of orthodontic treatment, but that cost was a major concern. Dental therapists were enthusiastic about the development and use of resources that could aid in the orthodontic screening and referral process.

Conclusions

This study has provided valuable insights into the current orthodontic referral process of New Zealand dental therapists. Variations among public and private therapists were identified. The implementation of an orthodontic referral guideline was viewed favourably by dental therapists.
Comparison of validity, repeatability and reproducibility of the Peer Assessment Rating (PAR) between digital and conventional study models
Authors: Pasapula Sridhar , Sherriff Martyn , Breckon Jeremy , Bister Dirk , Abela Stefan
Published: September 2021

Introduction

The validity, reliability and inter-method agreement of Peer Assessment Scores (PAR) from acrylic models and their digital analogues were assessed.

Method

Ten models of different occlusions were digitised, using a 3 Shape R700 laser scanner (Copenhagen, Denmark). Each set of models was conventionally and digitally PAR-scored twice in random order by 10 examiners. The minimum time between repeat measurements was two weeks. The repeatability was assessed by applying Carstensen’s analysis. Inter-method agreement (IEMA) was assessed by Carstensen’s limit of agreement (LOA).

Results

Intra-examiner repeatability (IER) for the unweighted and weighted data was slightly better for the conventional rather than the digital models. There was a slightly higher negative bias of -1.62 for the weighted PAR data for the digital models. IEMA for the overall weighted data ranged from −8.70 – 5.45 (95% Confidence Interval, CI). Intra-class Correlation Coefficients (ICC) for the weighted data for conventional, individual and average scenarios were 0.955 (0.906 – 0.986 CI), 0.998 (0.995 – 0.999 CI). ICC for the weighted digital data, individual and average scenarios were 0.99 (0.97 – 1.00) and 1.00. The percentage reduction required to achieve an optimal occlusion increased by 0.4% for the digital scoring of the weighted data.

Conclusion

Digital PAR scores obtained from scanned plastic models were valid and reliable and, in this context, the digital semi-automated method can be used interchangeably with the conventional method of PAR scoring.
Innovation in prediction planning for anterior open bite correction
Authors: Almuzian Mohammed , Almukhtar Anas , O’Neil Michael , Benington Philip , Al Anezi Thamer , Ayoub Ashraf
Published: September 2021

This study applies recent advances in 3D virtual imaging for application in the prediction planning of dentofacial deformities. Stereo-photogrammetry has been used to create virtual and physical models, which are creatively combined in planning the surgical correction of anterior open bite. The application of these novel methods is demonstrated through the surgical correction of a case.
Skeletal effects of the alteration of masseter muscle function
Authors: Mayne Robert J. , van der Poel Chris , Woods Michael G. , Lynch Gordon S.
Published: September 2021

Aim

To investigate the effects of muscle denervation and the introduction of the β2-adrenoceptor agonist, formoterol, on the relationship between muscles and underlying skeletal growth.

Method

Thirty-one (4-week-old) male Sprague-Dawley rats were assigned to four groups: Surgical Sham; Denervated; Denervated +β2-agonist; and β2-agonist only. The Surgical Sham group had the left masseteric nerve exposed but not sectioned. Both of the denervated groups had the left masseteric nerve exposed and sectioned. The groups receiving the β2-agonist had formoterol directly injected into the left masseter muscle every three days for eight weeks. Sixteen angular and linear skeletal measurements were assessed in the overall craniofacial region and the mandible via standardised digital radiography in three views: lateral head, submento-vertex and right and left disarticulated hemi-mandibles.

Results

The findings indicated that, following surgical denervation of the masseter muscle, there were significant changes in the muscle and in the subsequent development of the underlying skeletal structures. The post-surgical changes were largely offset by the administration of a β2-agonist, formoterol, which attenuated muscle atrophy. However, the administration of the β2-agonist only, without surgical denervation, did not lead to changes in skeletal facial form.

Conclusions

Denervation atrophy of the masseter muscle results in statistically significant changes in the development of the underlying skeleton. The changes, however, are localised to areas of muscle attachment. The administration of the β2-agonist, formoterol, despite its effect on muscle anabolism, does not have a significant effect on underlying skeletal growth.
The effect of the buccal corridor and tooth display on smile attractiveness
Authors: Niaki Esfandiar Akhavan , Arab Sepideh , Shamshiri Ahmadreza , Imani Mohammad Moslem
Published: September 2021

Aims

The aim of the present study was to evaluate the lay perception of the effect of the buccal corridor and amount of tooth- gingival display on the attractiveness of a smile in different facial types.

Materials and methods

Using Adobe Photoshop CS3 software, frontal facial images of two smiling Iranian female subjects (one short-faced and one long-faced) were altered to create different magnitudes of buccal corridor display (5, 10, 15, 20 and 25%) and tooth-gingival display (2 mm central incisor show, 6 mm central incisor show, total central incisor show, total tooth show with 2 mm gingival show and total tooth show with 4 mm gingival show). Sixty Iranians (30 males and 30 females) rated the attractiveness of the pictures on a 1–5 point scale.

Results

Narrower smiles were preferred in long-faced subjects compared with short-faced subjects. Minimal tooth show was more attractive than excessive gingival display in short-faced subjects. There were no gender specific, statistically significant differences found in the ratings given by the lay assessors.

Conclusions

Harmonious geometry of the smile and face in both the vertical and transverse dimensions influences smile attractiveness and this should be considered in orthodontic treatment planning.
Reliability of torque expression by the Invisalign® appliance: A retrospective study
Authors: Gaddam Raj , Freer Elissa , Kerr Brett , Weir Tony
Published: September 2021

Introduction: Incisal torque in orthodontics has always been important due to its relationship with smile aesthetics and the stability of a final treatment outcome. The aim of this study was to quantify the accuracy of torque expression predicted by ClinCheck® planning associated with Invisalign® treatment, compared to clinical outcomes.

Methodology: Forty adult patients consecutively treated using the Invisalign appliance were selected. Torque and the interincisal angle (IIA) were measured at T0 (pretreatment), T1 (predicted post-treatment), and R (end of initial aligner sequence) stages on STL files using metrology software (Geomagic Control X).

Results: The difference between the predicted and achieved torque (torque differential) was statistically significant (P < 0.001) in the labial crown torque group with a mean of 6.43° (SD = 7.09) for the upper central incisor, 5.06° (SD = 7.32) for the upper lateral incisor and 2.75° (SD = 5.7) for the lower incisor sub-groups. In contrast, the corresponding lingual/palatal crown torque sub-groups did not show a statistically significant torque differential (P >0.05). Similar observations were made for the IIA differential (difference between predicted and achieved IIA) with a mean IIA differential of 9° (SD = 10.73; P < 0.001) and -3.4° (SD = 7.9; P > 0.05) in the labial and lingual/palatal crown torque IIA groups, respectively.

Conclusions: Torque was under-expressed when the teeth were moving labially, and fully- or over-expressed when moved lingually, indicating Invisalign’s inefficiency in torqueing incisors in the labial direction.
The application of 3D metrology software in the quantitative and qualitative assessment of aligner treatment outcomes
Authors: Weir Tony
Published: September 2021

3D metrology software (Geomagic® Control X™) can be used in orthodontic treatment to significantly improve the analysis of achieved tooth movements compared with those predicted by treatment planning software, such as ClinCheck® software (Align Technology®). The applications of this technology enable clinicians to present more accurate and detailed case presentations and analyse their treatment outcomes. Additionally, information presented may further aid clinicians in interpreting and understanding metrology-derived information, in the form of digital heat maps, when incorporated into case presentations and scientific articles.
First law and quantum correction for holographic entanglement contour
Authors: Han Muxin , Wen Qiang
Published: September 2021

Entanglement entropy satisfies a first law-like relation, which
equates the first order perturbation of the entanglement entropy for the
region AA
to the first order perturbation of the expectation value of the modular
Hamiltonian, \delta S_{A}=\delta \langle K_A \rangleδSA=δ⟨KA⟩.
We propose that this relation has a finer version which states that, the
first order perturbation of the entanglement contour equals to the first
order perturbation of the contour of the modular Hamiltonian,
i.e. \delta s_{A}(\textbf{x})=\delta \langle k_{A}(\textbf{x})\rangleδsA(𝐱)=δ⟨kA(𝐱)⟩.
Here the contour functions s_{A}(\textbf{x})sA(𝐱)
and k_{A}(\textbf{x})kA(𝐱)
capture the contribution from the degrees of freedom at
\textbf{x}𝐱
to S_{A}SA
and K_AKA
respectively. In some simple cases k_{A}(\textbf{x})kA(𝐱)
is determined by the stress tensor. We also evaluate the quantum
correction to the entanglement contour using the fine structure of the
entanglement wedge and the additive linear combination (ALC) proposal
for partial entanglement entropy (PEE) respectively. The fine structure
picture shows that, the quantum correction to the boundary PEE can be
identified as a bulk PEE of certain bulk region. While the shows that
the quantum correction to the boundary PEE comes from the linear
combination of bulk entanglement entropy. We focus on holographic
theories with local modular Hamiltonian and configurations of quantum
field theories where the applies.
The main directions of the formation and implementation of the company's social policy
Authors: Нестеренко Е.С. , Финогентова А.В.
Published: September 2021

В статье авторами рассмотрена социальная политика фирмы как один из важнейших элементов функционирования современного предприятия. Выделены преимущества и возможности формирования и реализации социальной политики фирмы. Предложены основные направления и приоритеты внутренней и внешней социальной политики фирмы. В рамках раскрытия направлений социальной политики развития фирмы более детально рассмотрена сущность социальной ответственности фирмы. Обозначены основные концепции, уровни и направления социальной ответственности фирмы в рамках проводимой ей социальной политики.

In the article, the authors consider the social policy of the company as one of the most important elements of the functioning of a modern enterprise. The advantages and opportunities of forming and implementing the company's social policy are highlighted. The main directions and priorities of the company's internal and external social policy are proposed. As part of the disclosure of the directions of the social policy of the company's development, the essence of the company's social responsibility is considered in more detail. The main concepts, levels and directions of social responsibility of the company within the framework of its social policy are outlined.