Arch Length Research Articles

Orthopedic outcomes of hybrid and conventional Hyrax expanders.

To compare the effects of a hybrid miniscrew-supported expander versus a conventional Hyrax (CH) expander in growing patients. Forty patients were randomized into two groups: a hybrid Hyrax (HH) expander group using a Hyrax expander with two miniscrews and a CH expander group. The final sample had 18 subjects (8 female, 10 male; initial age of 10.8 years) in the HH group and 14 subjects (6 female, 8 male; initial age of 11.4 years) in the CH group. Cone-beam computed tomography examinations and digital dental models were obtained before expansion and 11 months postexpansion. The primary outcomes included the orthopedic transverse effects of expansion. Intergroup comparison was performed using analysis of covariance (P < .05). Significantly greater increases in the nasal cavity width, maxillary width, and buccal alveolar crest width were found for the HH group. No intergroup differences were observed for dental arch width or shape changes. The HH group showed greater increases in the nasal cavity width, maxillary width, and buccal alveolar crest width. No differences were observed for intermolar, interpremolar, or intercanine widths; arch length; or arch perimeter. Arch size and shape showed similar changes in both groups.

APPLICATION OF DENT@LIGN DIGITAL ALIGNERS FOR CORRECTION OF CROWDING

Purpose: To analyze the possibilities for correction of the crowding in the upper and lower dental arch with DENT@LIGN digital aligners. Materials and Methods: DENT@LIGN digital aligners (DLN) were applied for correction of the crowding in 127 patients, 69 of whom were treated in both jaws, 36–only in the upper and 22 –only in the lower. A complete orthodontic analysis of the patients before and after treatment was made. The patients were divided into four groups: without crowding; with mild crowding- up to 3 mm; with moderate crowding –– from 3.1 to 7.0 mm; with severe crowding - over 7.1 mm arch length deficiency. The DLN are applied into steps with optimal wearing of18-21 hours a day. Each step has to be worn for one month and consists of 3 aligners: soft (0.55 mm), medium (0.625 mm) and hard (0.75 mm). The results were statistically processed. Results: In the upper dental arch, the percentage of patients without crowding increased significantly after the treatment with DLN from 35% (N = 33) to 92.5% (N = 86). In the lower dental arch, the percentage of patients without crowding increased from 21% (N = 13) to 91.5% (N = 75). Conclusion: DENT@LIGN digital aligners are a successful and effective method for treatment of crowding in patients of all ages.

Accuracy of Model Estimation versus Tanaka and Johnston Arch Length Analysis.

This study examines how accurate pediatric dentists are at estimating dental arch lengths by comparing their model estimations (guesstimating the arch length without measuring) to the Tanaka and Johnston mixed dentition arch length analysis. This study consisted of two parts, a survey of practitioners and a model estimating and measuring component. The survey was designed and given to 44 pediatric dentists to determine how many were practicing orthodontics and using arch length analyses routinely. Then 18 pediatric dentists and 13 pediatric dental residents examined 20 sets of mixed dentition models and estimated how much space was available. These estimations were compared to the calculated gold standard, the Tanaka and Johnston arch length analysis of the same models. More than half of the dentists surveyed that practice comprehensive orthodontics use arch length estimates. Pediatric dentists and pediatric dental residents are just as good as each other at estimating arch length. Pediatric dentists and pediatric dental residents underestimated arch length by -3.6 and -3.1 mm, respectively. More research needs to be done to determine if model estimation is a clinically acceptable way to judge arch length.

Comparison of Tooth Widths, Arch Widths and Arch Lengths in Class-I Normal Dentition to Class-I and II Crowded Dentitions

Background and Objective:Dental study casts play a vital role in the diagnosis and treatment planning of various orthodontic cases. This study was carried out to compare the tooth widths, arch widths, and arch lengths in Class-I normal dentition to those in Class-I and Class-II crowded dentition in an effort to improve treatment planning and to eventually reduce treatment duration.Methods:Total 170 patients, 12 to 40 years of age with a complete set of permanent teeth till 1st molars; who presented to the Orthodontics Department at Armed Forces Institute of Dentistry (A.F.I.D), Rawalpindi from Sep 2019 to Feb 2020, were included in the study. Non-probability purposive method of sampling was used. The dental casts obtained were used to measure tooth widths, arch widths, and arch lengths. Subjects were classified into Class-I normal and Class-I and Class-II crowded occlusion and comparison of the sum of tooth widths, arch widths, and arch length discrepancies were determined among the three occlusion groups. Data was analyzed in SPSS version 21 and independent samples t-test was used to differentiate the variables of interest.Results:Out of 170 subjects, 73 (42.9%) subjects had Class-I normal occlusion while 97 (57%) had Class-I and Class-II crowded occlusions. No statistical difference was found between the occlusal groups with regard to the sum of tooth widths, inter-canine widths, inter-first premolar widths, inter-second premolar widths and inter-molar widths. However, a remarkable difference was observed between the occlusal groups with respect to arch perimeters and arch length discrepancies (p = 0.000 and 0.000 respectively).Conclusions:Results of the current study indicate that crowding of teeth occurs as a consequence of decreased arch perimeters which may lead to increased arch length discrepancies. However, no prominent difference was noticed in the sum of tooth widths and arch widths among different occlusal groups.

Reliability of odontometric parameters in stature analysis.

Background:To emphasize the role of odontometric parameters which may be used as a reliable forensic tool especially in cases with partial remains of the individualAim:To assess the reliability of odontometric parameters in stature analysisMaterials and Methods:The study was conducted on 100 patients (50 male and 50 Female). Mesiodistal width of anterior teeth, inter-canine width, Inter-premolar width and maxillary arch length were the parameters included. The results were tabulated with a linear regression formula obtained for each parameter.Statistical Analysis:The data collected was statistically analysed using SPSS version 20 and a linear regression formula was obtained thereafter.Results:Mesio-distal widths of individual maxillary canines, total mesiodistal width of maxillary anteriors and arch length showed a significant co-relation with stature. The combined linear regression formula was obtained for all parameters.Conclusion:Odontometric parameters of mesio - distal widths of individual maxillary canines, total mesiodistal width of maxillary anteriors and arch length can be used as reliable parameters for stature analysis.

In vitro comparison of the accuracy (precision and trueness) of eight dental scanners for dental bridge scanning

Dental scanners play a critical role in computer-aided design/computer-aided manufacturing technology. This study aimed to compare the accuracy (precision and trueness) of eight dental scanners for dental bridge scanning. In this in-vitro experimental study, a typodont model with a missing maxillary right first molar was prepared for a 3-unit fixed partial denture. Each scanner (Sirona inEos inLab, Sirona X5, Dentium, Imes icore 350I I3D, Amann Girrbach map 100, 3Shape D100, 3Shape E3) performed seven scans of the typodont, and the data were analyzed using 3D-Tool software. The abutment length, abutment width, arch length, and interdental distance were measured. To assess the accuracy of each scanner, trueness was evaluated by superimposing the scanned data on true values obtained by the 3shape Triosscanner as the reference. Precision was evaluated by superimposing a pair of data sets obtained from the same scanner. Precision and trueness of the scanners were compared using the one-way ANOVA followed by the post-hoc Tukey's HSD test and one-sample t-test (P<0.05 was considerer significant). The precision of scanners ranged from 14 μm (3Shape Trios) to 45 μm (Imes icore 350i), whereas the trueness ranged from 38 μm (3Shape d700) to 71 μm (Sirona X5). The reported trueness values for 3Shape Trios, Sirona inEos inLab, Sirona x5, Dentium, Imes icore350i, Amann Girrbach, 3Shape d700, and 3Shape e3 were 63, 45, 71, 67, 70, 53, 38, and 42 μm, respectively, whereas the precision values were 14, 29, 44, 34, 45, 44, 30 and 28 μm, respectively.

The effectiveness of Hawley and vacuum-formed retainer usage protocols on the stability of fixed orthodontic treatment results

Abstract Objectives: To compare the effectiveness of Hawley and vacuum-formed retainer (VFR) usage protocols on post-treatment stability. Methods: The inclusion criteria included patients who initially presented with mild or moderate pretreatment crowding and a Class I or Class II malocclusion. The retention protocols were defined as Group 1: Hawley retainers, 12 months full-time wear; Group 2: Hawley retainers, six months full-time, six months night-only wear; Group 3: VFR, 12 months full-time wear; Group 4: VFR, six months full-time, six months night-only wear. Study models were taken prior to treatment (T0), after debonding (T1), six months after debonding (T2), and 12 months after debonding (T3). Little’s irregularity index, intercanine and intermolar widths, arch length, overjet and overbite were measured. Repeated measure ANOVA with one-fixed factor, one-way ANOVA, Kruskal Wallis or Welch’s heteroscedastic F-test, were applied. Results: Fifty-eight patients were analysed at T2, and 52 patients at T3. There was no significant difference between the effectiveness of a Hawley appliance or VFRs on arch stability after six months. The intercanine width changes from the sixth to 12th month of retention showed a significant difference (p = 0.016) between Group 2 (-0.38 ± 0.58 mm) and Group 3 (0.39 ± 0.94 mm). Conclusions: Different wearing regimens of a Hawley appliance or VFR retainers did not reveal any difference determined by Little’s irregularity index. Full-time usage of VFRs provided better intercanine width retention than night-only Hawley retainer wear in the maxillary arch.

Obturating materials in pediatric dentistry: A review

Primary teeth should be preserved until their normal exfoliation time so as to maintain arch length and function in order to provide proper guidance for the eruption of permanent teeth, enhance esthetics and mastication, prevent aberrant tongue habits, aid in speech and prevent the psychological effects associated with tooth loss. Pulpectomy consists of removing the pulp tissue associated with micro-organisms and debris from the canal and obturating with resorbable filling material. Success rate of endodontic therapy depends on many factors like familiarity with the complexity of primary tooth canal systems, their formation and resorption pattern, obturating material as well as obturation technique used that is capable of densely filling the entire root canal system and providing a fluid tight seal from the apical segment of the canal to the cavo-surface margin in order to prevent reinfection. One of the major areas of research in pulpectomy is to discover new materials for obturation so to have the specific properties similar to teeth. This article will render the role of many important obturating materials which we use in dentistry and their advantages and disadvantages and their modifications.

Correlation between maxillary cuspid impaction with available space and anomalies of maxillary lateral incisors

Association of cuspid impaction with adjacent lateral incisor anomalies is under controversy. The aim of this study was to investigate the correlation between maxillary cuspid impaction with dental anomalies. In this in vitro experimental study, the material consisted of pretreatment dental records of 102 patients with at least one palatally or buccally displaced impacted permanent cuspid (palatal and buccal impaction groups). They were matched with a comparison control group of 102 patients having normally erupted maxillary cuspids. Available space, mesiodistal dimensions of teeth, and morphologic parameters of lateral incisors were measured using the digital caliper. Comparison of mean values of lateral incisors anomalies and severity of crowding between different groups were performed using the one-way ANOVA test, and the analysis of associations between position of the impaction and anomaly of the lateral incisors and severity of crowding was performed using the Chi-square test. P < 0.05 was considered statistically significant. There was no statistically significant difference in the arch length-tooth size discrepancy between the cuspid impaction groups and control group. The impaction group (buccal or palatal) presented statistically significant differences in terms of anomalies of maxillary lateral incisor compared to the control group. Peg-shaped lateral incisor was related to buccal cuspid impaction and microdontia had relationship with palatal cuspid impaction. There is the relationship between cuspid impaction and adjacent lateral incisor abnormality, but no difference was observed between buccal and palatal cuspid impactions. Crowding revealed no relationship with cuspid impaction (buccal or palatal) in this study.

МОЛОЧНАЯ ПРОДУКТИВНОСТЬ КОРОВ РАЗНЫХ ЭКСТЕРЬЕРНО-КОНСТИТУЦИОНАЛЬНЫХ ТИПОВ

Improvement of the genetic potential in terms of cows’ productivity and creation of high milk-yield cattle with good health and long productive lifetime characteristics is impossible without systematic evaluation of such traits as milk-yield, exterior, and constitution type. The aim of our research was to study the trends in exterior traits genetic selection parameters changing, determine the extent of interconnection between cow productivity traits and constitution type among the Black-Motley and Kholmogory cow breeds of the Udmurt Republic. The research based on cow breeding-stocks was carried out in 2018–2020. The sampled population included 449 specimens. The whole cow population to be analyzed was divided in 3 groups by the productivity level: 1 – low (up to 6,000 kg); 2 – moderate (from 6,000 to 8,000 kg); 3 – high (over 8,000 kg). High milk-yield cows were higher – withers height was higher by 1.5% and 1.4% (P &lt; 0.05) – and had more elongated body (by 1.0% and 0.8%) as compared with the 1st and 2nd group specimens. Low milk-yield cows (up to 6,000 kg) had short stature and big-boned constitution type with better-developed skeleton. They had greater values of such parameters as the chest width (by 1.6%), wide hip width (by 7.3%, P &lt; 0.01), width of loin (by 13.2%, P &lt; 0.01), and metacarpus girth (by 3.2%, P &lt; 0.05). Cows with a productivity level over 8,000 kg of milk per 305 days of lactation had relatively high value of the Pelvic arch length (by 2.0% and 2.3%, Р &lt; 0.05) and the depth of loin (by 1.3% and 1.5%) with insignificant difference in rump bone length. The lowest value of the mean exterior index of constitution type (by 3.0%, P &lt; 0.05) was observed in high milkyield cows that is the evidence of the constitution proportionality, namely, optimal relation between the body volume and the height of a cow. Moreover, the Pelvic arch index – the ratio of the Pelvic arch volume to the body length – also testifies to harmonious constitution. High milk-yield cows demonstrated this index to be the lowest (by 3.8%, Р &lt; 0.01) and featured more harmonious constitution.

Assessment of role of mandibular third molar in lower anterior crowding among orthodontic patients of Kathmandu Nepal

Introduction: Crowding in mandibular arch increases with increasing age and etiology of crowding is multifactorial in nature. Role of mandibular third molar in lower anterior crowding remains a topic of controvery over a period of century. The objective of this study was to assess whether there is any correlation between presence of mandibular third molar position and lower anterior crowding.&#x0D; Materials and Method: On the basis of third molar position one hundred and six sample of pretreatment orthodontic patients aged between 17 to 38 years were divided into erupted, erupting and agenesis group. The study was conducted in Peoples Dental College and Hospital from January 2020 to March 2020 after obtaining ethical approval from the institutional review committee. This cross-sectional study was done on dental casts and orthopantomogram; brass wire was used for measuring arch length and digital vernier caliper for measuring tooth material with modified segmental arch analysis method.&#x0D; Result: Among 106 samples collected 55 (51.88%) were female and 51(48.11%) were male and the mean age was 21.53 ± 3.91 years, Chi square and ANOVA test was used for Statistical analysis. This study showed no statistically significant differences between third molar position and lower anterior crowding on right (P= 0.68) and left side (P = 0.45). The study also showed that association between the third molar position and lower anterior crowding is more on left side compared to right side.&#x0D; Conclusion: Mandibular third molars have not statistically significant difference in lower anterior crowding so, extraction of third molars for relieving the anterior crowding is not justifiable

Maximum equivalent stress induced and the displacement of the developing permanent first molars after the premature loss of primary second molars: A finite element analysis.

The use of a space maintainer during the deciduous dentition period at a proper time can prevent the consequences of the loss of the arch length in the future. There is controversy over the use of space maintainers. The aim of this study was to evaluate the magnitude of stresses exerted on immature permanent molar teeth, and the extent of displacement of these teeth when the adjacent teeth are missing, but after placing a space maintainer. Studies carried out to date have used clinical measurements, e.g., X-rays and dental casts. The finite element model (FEM) was used for modeling the maxillary and mandibular teeth and the bone structure. A space maintainer (band and loop) was also designed for modeling. Force was applied and a finite element analysis (FEA) was carried out in 6 states in the maxilla and in the mandible to evaluate the distribution of stresses and the amount of displacement of immature permanent first molar teeth in the presence or absence of deciduous second molar teeth and a space maintainer. During mastication, when the deciduous second molar tooth was absent, the maximum stress was transferred to incomplete roots. When there was a space maintainer, stress was transferred to the space maintainer itself and to the distal side of the deciduous first molar tooth. The displacement of permanent first molar teeth was minimal in the presence of all teeth; in the absence of the deciduous second molar tooth, this displacement increased 4-5-fold, which decreased again almost to the level of the 1st/4th state (intact arch) in the presence of the space maintainer. The results showed the importance of the use of space maintainers, as they significantly decrease the momentary displacement of the teeth as well as the stress exerted on the developing permanent first molar teeth.

Analysis of dental and basal bone arch form correlations in skeletal Class Ⅱ malocclusion

This study aimed to establish mathematical equations to describe the dental and basal arch forms in skeletal Class II malocclusion and to investigate correlations between these forms to facilitate clinical diagnosis and treatment design. Cone-beam computed tomography images of 60 patients (30 each with skeletal Class II malocclusion and normal occlusion) were subjected to 3-dimensional volume rendering, image reconstruction, and measurement. Using a computer program written in Java on the Eclipse platform (EclipseFoundation, Ottawa, Canada), a beta function was used to establish mathematical models of dental and basal bone arch forms, and model-fitting was performed. A mathematical model was developed to describe the dental and basal arch forms in skeletal Class II malocclusion. The maxillary and mandibular dental arch lengths were significantly longer in skeletal Class II malocclusion than in normal occlusion, whereas the width of the maxillary molar segment was smaller. The maxillary molar and mandibular intercranial segments in the basal arch were significantly longer in skeletal Class II malocclusion than in normal occlusion, whereas the mandibular intercranial segment width was smaller. The dental arch and basal bone arch forms in the maxilla and mandible follow individual curves, described by a beta function. In skeletal Class II malocclusion, the dental and basal arches are discrepant in horizontal and anteroposterior dimensions, which should be considered during orthodontic treatment planning to improve arch matching.

Prediction of the Dental Arch Perimeter in a Kurdish Sample in Sulaimani City Based on Other Linear Dental Arch Measurements as a Malocclusion Preventive Measure.

The current study aimed to find a prediction equation to estimate the arch perimeter (AP) depending on various arch dimensions including intercanine width (ICW), intermolar width (IMW), interpremolar width (IPMW), and arch length (AL) in a sample of the Kurdish population in Sulaimani City. The study sample was 100 pairs of preorthodontic dental casts. Calculations of dental arch dimensions and perimeter were performed by a digital vernier. Statistical analysis was performed via using the SPSS version 25 software. The developed prediction equation for the upper arch was Y = +1.3 × (arch length) + 1 × (intermolar width), whereas the equation for the lower arch was Y = +0.9 × (intermolar width) + 0.92 × (intercanine width). Paired t-test revealed no statistical difference between predicted and real arch perimeters. Two separate prediction equations for upper and lower arches were developed based on the arch length (AL) and intermolar width (IMW) for the maxillary arch, intermolar (IMW), and inter canine widths (ICW) for the lower arch. The developed equations could have further beneficial impacts on orthodontic diagnosis and treatment planning.

G–technique: An effective and precise method for rapid Derotation of teeth

Rotations are mesiolingual or distobuccal intra-alveolar displacement of tooth around their long axis. Canine or premolars must often be derotated during fixed appliance therapy. Derotation of posterior teeth provides space which can be utilized for relieving crowding in the anterior region. By correction of these rotations one to three mm of arch length can be gained per side. Biomechanical principles involve application of single or couple of forces for correction of rotation. Rotated teeth can be corrected by removable, semifixed or fixed appliance depending upon the severity of rotation. Whatever the technique used, derotation especially of posterior teeth should be achieved quickly so that the gained space can be used for relieving crowding. Keywords: Derotation; G – Technique; leveling; aligning

Maxillary arch expansion along with fixed mechanotherapy using different expansion devices

Malocclusions can exist in all the three planes of space i.e in antero – posterior, vertical and transverse plane. Transverse discrepancies can manifest as dental, skeletal or functional discrepancies. Maxillary expansion is one of the most common treatment modality for arch length augmentation, posterior crossbite correction and removing cross arch interferences. Skeletal correction is done by orthopedic expansion or surgical expansion. Rapid Maxillary Expansion and Head Gears, produces orthopedic correction. Severe skeletal discrepancies require surgical correction of underlying skeletal deformity by using SARPE (Surgically Assisted Rapid Palatal Expansion) or surgical expansion of palatal shelves by midline osteotomies. Dental correction can be done using Rapid expansion in growing children and by slow expansion using Quad Helix, W Arches, Coffin Spring and certain modification of Jack screw appliances in other cases. In patients treated with fixed mechanotherapy expansions can not only be achieved by Arch wires, auxillary Jockey arches, cross elastics etc. but also by slow or rapid expansion devices that can be amalgamated with fixed orthodontic treatment. In this article, the use of slow maxillary expansion appliances in treatment of the three patients with transverse maxillary deficiency and undergoing fixed mechanotherapy will be discussed. Keywords: Expansion

Taxonomic significance of vertebral column and caudal skeleton of clupeid fishes (Teleostei: Clupeiformes) of Iran

AbstractClupeiformes (generally known as herrings, shads and sardines) with a synapomorphy of recessus lateralis are globally distributed marine, freshwater and diadromous species classified in seven families including the family Clupeidae. In this study, a comparative analysis of the vertebral column and caudal skeleton of twelve clupeid species was conducted on the basis of X‐ray imaging and usual staining method of bones and cartilages. Several osteological features including number of principal branched caudal rays bearing with hypurals on both lobes of the caudal‐fin; number, length, arrangement and shape of epural bones; shape and length of haemal and neural spines of the penultimate vertebrae 2, 3 and 4; length and shape of parhypural; length and shape of neural arch of the urostyle; distribution of the dorsal and procurrent rays, and fusion of parhypural with preural centrum 1 (PU1) were investigated and a detailed account of these structures were provided. The results reveal that the neural spine of the 2nd, 3rd and 4th penultimate vertebrae (NSPU2, NSPU3 and NSPU4) was generally narrow and broad in lower and pointed at upper part with some variation in the size and position related to the dorsal edge of the body in different taxa. The neural arch of the urostyle (Na) has been observed as spindle, lance‐like or knife‐like. It is usually long (≥1/2 length of the NSPU2) with some modification in the studied species. Two or three curved, straight, cone‐shape or pin‐shaped epurals were found in all species with the same number in congeneric species. Opisthural cartilage (O) lays between HYP6 and PLS anteriorly, located at the tip of PLS or traversed horizontally. The presence of this cartilage made a gap between first (longest) and second unbranched caudal rays in upper part of caudal‐fin. It showed six varied shapes (e.g. fusiform, golf club‐like, horn shape, trapezoid shape, crescent and triangle) with different size in comparison with HYP6. This comparative study revealed that some osteological characters such as shape and position of opisthural cartilage, shape of neural arch of the urostyle, and number of epurals could be used as suitable features for the identification of the studied clupeids at the species and genus levels. The improved knowledge of the skeletal structures provided here, can also facilitate the correct identification of clupeid fossils.

Effect of nanoparticle on growth, biochemical and anatomical characteristics of moringa plant (Moringa oleifera L.) under salinity stress condition

Two pot experiments were carried out at the Experimental Farm of the Agricultural Botany Department, Faculty of Agriculture, Al-Azhar University (Assiut branch), Assiut, Egypt, during two successive seasons of 2018 and 2019. The main aim of this study was to find out the effect of both of foliar application with some growth promoters (using nanotechnology) i.e., zinc, iron, copper oxide nanoparticles at 50, 100 and 150 mgl-1 of each and silica nanoparticles at 20, 40 and 60 mgl-1 as well as salinity stress level of irrigation water at 9000 mgl-1 individually and their interactions on growth, biochemical and anatomical characteristics of Moringa oliefera L. plant. The results showed that individually salinity stress level of irrigation water at 9000 mgl-1 decreased all studied vegetative growth parameters of moringa plant i.e., plant height (cm), stem diameter (cm), leaves number plant-1, leaf area plant-1 as well as root, stem and leaves dry weights plant-1 compared with the control. The same trend was obtained in photosynthetic pigments content (total chlorophyll) as well as the studied anatomical characteristics of root section (i.e., root diameter of V.C and length of xylem arch), stem section (i.e., stem diameter, O of V.C, length of V.B in the stem) and Leaf blade section (i.e., upper epidermis thickness, lower epidermis thickness and mesophyll tissue for leaflet) at 50 days of Moringa oliefera leaves compared with unstressed plant. On other hand, salinity stress level at 9000 mgl-1 resulted in increasing antioxidant activity as well as total phenolic contents at 60 days of Moringa oliefera leaves compared with unstressed plant. Data also indicated that the individually foliar application treatments with Zinc, Iron, Copper oxide nanoparticles at 50, 100, 150 of each and Silica at 20, 40, 60 mgl-1 nanoparticles increased studied vegetative growth as well as anatomical characteristics, chemical compositions, photosynthetic pigments (total chlorophyll), antioxidants activity and total phenolic contents of moringa plant compared with the control treatment. In this respect, Silica nanoparticles at 60 mgl-1 followed by zinc and iron oxide at 150 mgl-1 nanoparticles of each were the most effective treatments, respectively. Finally , Based on these results, it could be concluded that the foliar application with nanoparticles gave the highest Valois of morphological, chemical compositions and anatomical characteristics its that reduce the harmful effects of salinity stress of Moringa oliefera L. plant specially at silica 60 mgl-1,. Data recorded that this results using it under the same field conditions (Assiut governorate, Egypt).

Effects of Combined Rapid Maxillary Expansion and Facemask Therapy on the Mandibular Dental Arch in Mixed Dentition.

The aim of this study was to evaluate changes in the mandibular dental arch and incisor alignment induced by combined bonded Rapid Maxillary Expansion (RME) and Face Mask (FM) therapy in the mixed dentition stage in which leeway space was used throughout the treatment. This retrospective study evaluates pretreatment (T0) and posttreatment (T1) cephalometric radiographs and orthodontic models of 25 patients (mean age: 10.75±2.64), in mixed dentition, having skeletal Class 3 anomaly (ANB<0) with maxillary retrognatism (SNA=77.2±0.68) and bilateral posterior crossbite treated with bonded Hyrax RME-FM. Mean treatment duration was 10.4 months. Dental model measurements were performed using the 3Shape OrthoAnalyzerTM 2013-1 program. Changes in the mandibular incisor and first molar positions were determined on cephalometric radiographs. Statistical evaluation was done with a paired t-test. A significant increase of 1.2 mm was found in intermolar width (p<0.001) in the mandibular dental arch. There was a significant decrease (1.4 mm) (p<0.001) in arch depth and an increase in arch length discrepancy (1.7mm)(p<0.01). There was a significant increase (0.8mm) (p<0.05) in the incisors' irregularity score (LII). IMPA showed a significant decrease (p<0.05). Clinicians should be aware that mandibular crowding tends to increase during this type of combined therapy.

Effect of Class II camouflage treatment on anterior arch length ratio and canine relationship

To evaluate the influence of compensatory tipping of maxillary and mandibular incisors on the anterior arch length ratio and canine relationship in skeletal Class II malocclusion. The study was based on posttreatment lateral head films and dental casts of 88 patients. The sample was divided into a Class II malocclusion group (32 patients; ANB ≥5° and mean [± standard deviation] age, 20.82±7.67years) and a Class I malocclusion group (56 patients; 1°≤ANB≤2.5° and mean [± standard deviation] age, 19.20±5.04years). Measurements obtained for anterior arch length and width, Bolton discrepancy, canine relationship, growth pattern, and incisor position were compared between the groups. The canine relationship was correlated with dental and skeletal variables (P<0.05). The mean ANB angles were 6.21° and 1.78° for the Class II and Class I malocclusion groups, respectively. The skeletal Class II group presented significantly larger mandibular anterior arch length, producing an unbalanced anterior arch length ratio. The canine relationship was more displaced toward Class II in this group. Anterior arch length ratio was the most influential variable in the canine relationship. The mandibular incisors had a higher compensation degree than the maxillary incisors. The groups were similar regarding overjet, overbite, and growth pattern. Class II malocclusion camouflage treatment with excessive proclination of the mandibular incisors was associated with an increase in mandibular arch length, negatively influencing the anterior arch length ratio and the final canine relationship. Mandibular anterior arch length reduction by interproximal stripping may be necessary in moderate to severe skeletal Class II malocclusion orthodontic treatment.