Prediction of arch perimeter based on arch width as a guide for diagnosis and treatment planning

Abstract Background The choice between extraction and expansion treatment is an endless debate in orthodontics. Ethnic and secular variations showed that there was a change in arch perimeter over the last 50 years. Accordingly, the purpose of this study was to investigate the relation between the arch perimeter and the intercanine and intermolar widths in normal occlusion. Also, to design regression equations for the prediction of the arch perimeter based on arch width, in a sample of the Egyptian population. The images of 340 cast pairs for 11 to 13-year-old patients were traced using TracerNet. Intercanine width, intermolar width and arch perimeter were measured, statistical analysis was performed and regression equations for both arches were formulated. Results There was a positive correlation between the lower arch AP, ICW and IMW and between the upper arch AP and ICW. Lower arch perimeter = 0.536 I33 + 71.642, lower arch perimeter = 0.828 l66 + 58.604 and upper arch perimeter = 1.988 U33 + 30.492 were the significant derived equations. Conclusions The formulation of regression equations offers a tool for the prediction of arch perimeter or arch width that can act as a guide in diagnosis and treatment planning.

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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

Computational and Mathematical Methods in Medicine ◽

10.1155/2020/8869996 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Fadil Abdullah Kareem ◽

Aras Maruf Rauf ◽

Arass Jalal Noori ◽

Trefa M. Ali Mahmood

Keyword(s):

Statistical Analysis ◽

Treatment Planning ◽

Statistical Difference ◽

Preventive Measure ◽

Prediction Equation ◽

Diagnosis And Treatment ◽

Dental Arch ◽

Prediction Equations ◽

Lower Arch ◽

Maxillary Arch

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.

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Relationship among Lower Arch Length, Arch Width and Arch Perimeter in Crowding and Non-Crowding Groups

Balkan Journal of Dental Medicine ◽

10.1515/bjdm-2015-0027 ◽

2015 ◽

Vol 19 (1) ◽

pp. 8-12

Author(s):

Mimoza Selmani ◽

Julijana Gjorgova

Keyword(s):

Associated Factors ◽

Study Groups ◽

Class I ◽

Arch Width ◽

Normal Occlusion ◽

The Right ◽

The Relationship ◽

Lower Arch

SUMMARYCrowding is one of the causes of class I malocclusion. The purpose of the present study was to examine the relationship between arch length, arch width and arch perimeter in crowded and non-crowded arches, as well as to made comparison of the right and left sides between them and to find out the contributing factor in lower arch crowding. The study groups consisted of 60 subjects aged 16 to 21 years. First group consisted of 30 pairs of dental study models with class I normal occlusion. The second group consisted of 30 pairs of study models with class I crowding. Measurements of arch length and width were made as defined by Lavelle and Foster, using Korkhaus callipers. Arch perimeter was measured by Lundstrom method’s using manual calliper with sharp points. Differences between these measurements were made by Mann-Whitney U test (Z/U).According to our study, the arch length and arch perimeter were not associated factors in contribution to lower arch crowding. In association of contributed factors on the lower arch crowding, we could mention the width of the arch, because the differences between the two groups was significantly different.

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CEPHALOMETRIC NORMS FOR GUJARATI CHILDREN - A CROSS SECTIONAL STUDY

International Journal of Research -GRANTHAALAYAH ◽

10.29121/granthaalayah.v8.i4.2020.42 ◽

2020 ◽

Vol 8 (4) ◽

pp. 313-326

Author(s):

Purv Shashank Patel ◽

Purv S Patel ◽

M Ganesh

Keyword(s):

Gender Differences ◽

Statistical Analysis ◽

Standard Deviation ◽

Treatment Planning ◽

Ethnic Groups ◽

Primary Schools ◽

Pearson Correlation ◽

Mixed Dentition ◽

Diagnosis And Treatment ◽

The Mean

Introduction: Orthodontists have relied on cephalometric radiographs for orthodontic diagnosis and treatment planning since the advent of cephalometric radiography. The variations in different ethnic groups within the same country creates a need for cephalometric norms for each of such ethnic groups. McNamara’s analysis is the most commonly used and most suitable for diagnosis and treatment planning. Aim: The study aims to formulate cephalometric norms for Gujarati boys and girls using McNamara’s analysis. Materials & Method: The sample of children for the study was selected from the government funded primary schools of Gujarat. The sample size consisted of 250 school going Gujarati children (125 boys and 125 girls) with age ranging from 9 to 12 years. Materials & Method: A digital lateral cephalograph was taken under standard conditions for all children and manual tracings were done for identifying all cephalometric landmarks. The analysis was done using McNamara’s analysis and statistical analysis was done Statistical Analysis: Gender differences were calculated using student’s t test. The software was utilized to calculate the mean value, standard deviation, range, maximum and minimum values for all parameters of McNamara’s analysis for Gujarati boys as well as girls. The inter examiner variability was tested using Karl Pearson correlation test. Results: The mean and standard deviation with minimum values, maximum values and range for each of 11 parameters were calculated for all male and female subjects. The gender differences were also calculated for all subjects. Conclusion: This study introduces cephalometric norms for the mixed dentition period using McNamara Analysis for Gujarati children residing in Ahmedabad – Gandhinagar districts of Gujarat which can be utilized for orthodontic treatment in the future.

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Some Thoughts on Undergraduate Orthodontic Training Viewed by a Regional Consultant

British Journal of Orthodontics ◽

10.1179/bjo.9.2.95 ◽

1982 ◽

Vol 9 (2) ◽

pp. 95-97 ◽

Cited By ~ 2

Author(s):

W. G. Webb

Keyword(s):

Treatment Planning ◽

General Practitioners ◽

Theoretical Background ◽

Diagnosis And Treatment ◽

Graduate Courses ◽

Post Graduate ◽

Normal Occlusion ◽

Orthodontic Training ◽

Removable Appliance

The emphasis in the undergraduate orthodontic curriculum should be on understanding the principles of removable appliance therapy. The student must be able to design and adjust these appliances and to realise their limitations. The effect of extractions with or without appliance therapy should be stressed. Some theoretical background is needed on the development of normal occlusion and its variations, and on diagnosis and treatment planning but the emphasis should be on the practical aspects of treatment. This means that the practitioner will then be in a position to treat the more simple cases to a consultant prescription. Obviously this knowledge can be expanded on short post-graduate courses for general practitioners and ideally with clinical attachments in a Regional orthodontic department for the most interested.

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Determination of Tweed's cephalometric norms in Bengali population

European Journal of Dentistry ◽

10.4103/ejd.ejd_274_16 ◽

2017 ◽

Vol 11 (03) ◽

pp. 305-310

Author(s):

Lalima Kumari ◽

Anuranjan Das

Keyword(s):

Treatment Planning ◽

Mean Value ◽

Diagnosis And Treatment ◽

Mandibular Angle ◽

Mandibular Plane ◽

Normal Occlusion ◽

Lateral Cephalograms ◽

Males And Females ◽

The Mean

ABSTRACT Objective: The purpose of this study was to establish Tweed's cephalometric norms for Indian Bengali population and to compare it with Caucasian norms. Materials and Methods: The participants were of 50 adults with normal occlusion and pleasant profile. Lateral cephalograms were taken in natural head position, and cephalometric norms were established using Tweeds diagnostic triangle. Results: The study showed more proclined lower incisors in comparison with Caucasians. The result of the study also indicated that separate norms should be considered for Bengali males and females during diagnosis and treatment planning as mean Frankfort mandibular angle value for females was found to be significantly higher than that of males (t 48= 2.97; P < 0.01) and the mean value of incisor mandibular plane angle for males was significantly higher than that of females. Conclusion: The findings emphasize the need for group-specific norms for orthodontic diagnosis and treatment planning and provide cephalometric standards for normal Bengali adults.

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Overjet at the Anterior and Posterior Segments: Three-Dimensional Analysis of Arch Coordination

The Angle Orthodontist ◽

10.2319/041108-205.1 ◽

2009 ◽

Vol 79 (3) ◽

pp. 495-501 ◽

Cited By ~ 8

Author(s):

Yoon-Ah Kook ◽

Mohamed Bayome ◽

Soo-Byung Park ◽

Bong-Kuen Cha ◽

Young-Wuk Lee ◽

...

Keyword(s):

Statistical Analysis ◽

Anterior Segment ◽

Three Dimensional ◽

3D Scanner ◽

Second Molar ◽

3D Cad ◽

Arch Width ◽

Normal Occlusion ◽

Significant Difference ◽

Homogenous Distribution

Abstract Objectives: To compare the amounts of anatomical overjet measured from facial axis (FA) points with the amounts of bracket overjet measured from bracket slot center (BSC) points. Materials and Methods: The samples consisted of 27 subjects with normal occlusion whose models were fabricated with a three-dimensional (3D) scanner and the 3Txer program (Orapix Co Ltd, Seoul, Korea). 3D virtual brackets (0.022″ Slot, MBT setup, 3M Unitek, Monrovia, Calif) constructed with a 3D-CAD program were placed on an FA point with the 3Txer program. The arch dimension and the amounts of overjet from FA and BSC points were measured. Paired t-tests and analysis of variance (ANOVA) tests were used for statistical analysis. Results: No significant difference in arch width and depth was observed between FA and BSC points. Although the amounts of overjet measured from FA points showed homogenous distribution, a tendency to decrease from the anterior segment (2.3 mm) to the posterior one (2.0 mm) was noted. However, the amounts of overjet measured from BSC points were variable, especially in the premolar and molar areas. Significant discrepancies in the amounts of overjet in most of the areas between FA and BSC points (more than P < .05), except the lower second premolar and second molar areas, were reported, even though insets and offsets are part of the prescription for the base of straight-wire appliance (SWA) brackets. Conclusions: The hypotheses that the amount of overjet measured from BSC points was 3 mm through the whole segments and that distribution of the amounts of overjet from BSC points was the same as that from FA points were rejected.

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