Dental Arch Dimensions in Saudi Adults

Mandibular Interincisor and Intercanine Width at Three Different Stages of Dentition: A Cross-sectional Study

Background and objective

Malocclusion is a manifestation of normal biological variability, defined as a misalignment of the teeth or an incorrect occlusion between the upper and lower dental arches. This study aimed to evaluate the mandibular intercanine primary, mixed, and permanent dentition in school children of Shimla, Himachal Pradesh.

Materials and methods

This cross-sectional study was conducted on 1,392 children between the ages of 4 and 18 years from schools that fulfilled the inclusion criteria. The dental casts were poured and further divided based on the dentition stage, i.e., primary, mixed, and permanent dentition stages. Mandibular arch widths-interincisor and intercanine were measured on the casts by a digital vernier caliper.

Results

The statistically significant difference was found as the interincisor width increased from primary to mixed dentition and between males and females for permanent dentition. Intercanine width significantly increases from primary to mixed dentition and gradually from mixed to permanent dentition stages.

Conclusion

The present study found that there is a significant increase in interincisor and intercanine width in the lower dental arch from primary dentition to permanent dentition.

How to cite this article

Singhal P, Jaswal O, Thakur S. Mandibular Interincisor and Intercanine Width at Three Different Stages of Dentition: A Cross-sectional Study. Int J Clin Pediatr Dent 2024;17(4):417-424.

Analysis of the Facial Measurements and Dental Arch Dimensions for the Construction of Dental Prostheses among Adult Yemenis

AIM

To investigate the dental arch dimension (width, length, and height) and facial measurements including inner-canthal width (ICW), bizygomatic width (BZW), inter-alar width (IAW), and mouth width (MW), and to assess the correlation between these facial measurements and dental arch width (canine width [CW], inter-first premolar width [I1PW], and inter-first molar width [I1MW]), to establish a preliminary reference for artificial teeth selection in Yemeni adult.

MATERIALS AND METHODS

The study included 80 individuals (40 males and 40 females) with symmetrical faces and normal class I occlusion ranging in age from 20 to 35. Maxillary and mandibular stone casts were made for each individual. The dimensions of dental casts and facial measurements, including ICW, BZW, IAW, and MW, were assessed using a digital caliper. The collected data were analyzed by using the SPSS software program. The descriptive statistics for each measurement were made. Differences between males and females were tested using an independent-sample t-test with p-values below 0.05 considered significant. Pearson correlation coefficient between facial measurements and dental arch width was also done.

RESULTS

Most dental arch dimensions and facial measurements exhibited larger mean values in the male than in the female group, with the greatest significant difference in the maxillary dental arch width and the lowest in mandibular dental arch length. A highly significant correlation is observed between ICW and maxillary canine width (CW) (r = 0.318, p = 0.004). In contrast, no significant correlation between dental arch width and BZW, IAW, and MW is shown.

CONCLUSIONS

Within this study's limitations, the ICW can determine the ideal dimension of the artificial teeth in the anterior maxillary arch. While the other facial parameters, including BZW, IAW, and MW, cannot be used for artificial teeth selection in Yemeni populations.

CLINICAL SIGNIFICANCE

The findings of this study established a reference database of facial measurements and their correlation to dental arch and teeth width in Yemeni populations. So, it can be implemented in artificial teeth and dental prostheses design and construction.

Morphometric analysis of maxillary arch dimensions using Cone Beam Computer Tomography (CBCT)

Knowledge of morphology of the maxillary arch is important in many spacialities of dentistry. This retrospective cross-sectional study was performed using 109 randomly selected maxillary CBCT images of patients in the age range of 18-60 from the archives in Faculty of Dental Sciences, University of Peradeniya, Sri Lanka. EzDent software was used for measurements. Measurements related to the width were acquired from coronal sections while the measurements related to antero-posterior dimensions were performed on axial sections. A majority had an oval shaped maxillary arch (64.8%) followed by V shaped one.(29.2%). The mean height of the alveolar ridge at the upper canine position was 8.9 mm and the mean height of the alveolar ridge at the first molar level was 20.1 mm. Mann Whitney U test was used to compare measurements of variables between males and females. Difference in the height of alveolar ridge at the junction of soft and hard palate, width of the alveolar ridge at the canine, first molar and second molar and also the antero-posterior distance of the arch at the inter canine distance and junction between the hard and soft palate were statistically significant. Kruskal Wallis test was used to compare the differences between age groups. Chisquare values didnot indicate significant differences of measurements according to the age group of the participants. In conclusion, there is a significant difference in all maxillary arch parameters between the different genders. No significant differences in arch parameters were observed among the different age groups.

Unexpected malocclusion in a 13,000-Year-old Late Pleistocene young woman from Mexico

To analyze the etiological factors behind the malocclusion of a Late Pleistocene woman (named Naia), who is the best-preserved of the earliest individuals of the American continent. The examination of Naia’s malocclusion was performed through cephalometric and occlusal analyses, and by measuring her mandible. Her data were then compared to published data for modern, medieval, and postmedieval samples and seven Late Pleistocene individuals. Naia presented her permanent dentition fully erupted, except for the impacted mandibular third molars. She presented a class II molar malocclusion with crowding. The dental widths and mandible measurements were similar to or smaller than modern standards. The degree of dental wear was light. The cephalometric analysis confirmed a skeletal class II relationship, with a retrusive mandible and protruded upper incisors. Naia’s mild level of dental wear is consistent with a low masticatory force, in a time when the norm was a high amount of grinding. The low masticatory forces help explain Naia’s small jaws and crowding. However, it does not clarify Angle’s class II relationship. Naia is an example that environmental factors are insufficient to explain the onset of malocclusions and emphasizes the importance of understanding hereditary factors’ role.

Correlation of Three Dimensions of Palate with Maxillary Arch Form and Perimeter as Predictive Measures for Orthodontic and Orthognathic Surgery

Hard palate is regarded as an important part of the human skull, which contributes to the separation of the oral and nasal cavities. The aims of the study were to investigate the morphology of the hard palate in order to create a general guideline of three-dimensional values of the palate in a Kurdish sample in the city of Sulaimani as well as determining the possible correlations between different palatal parameters in class I malocclusion with the maxillary arch form and perimeter. A retrospective study design was adopted by collecting 100 study models of orthodontic patients aged 16–24 years old attending different private dental clinics in the city of Sulaimani seeking orthodontic management. In this study, three-dimensional palatal measurements including depth, length, and width were measured in an attempt to discover their correlation with each maxillary arch form and perimeter. Additionally, measurements of inter-molar width, inter-canine width, and arch perimeter were carried out. About two-thirds of those seeking orthodontic treatment were females. Nearly 80% of the study sample had narrow palate followed by 15 and 5% of intermediate palate and broad palate, respectively. In regard to arch form, almost 90% of subjects were with tapered maxillary arch form and 10% of them with oval arch form. Males had increased dimensions compared to females, with significant differences, except in palatal depth in the molar area, and palatine height index, in which females showed increased dimensions than males but the differences were statistically non-significant. A strong positive correlation was observed between arch form and canine depth. In regard to arch perimeter, a strong negative correlation was found with molar depth and a medium positive correlation with each of canine depth, palatal width, and palatal length.

Maxillary and mandibular dental arch forms in a Jordanian population with normal occlusion

Background

Ethnic background has been claimed to affect arch form. The purpose of this study was to describe and elucidate the maxillary and mandibular arch forms in Jordanian population and to develop a classification method for these forms which could be employed to construct orthodontic archwires accordingly.

Methods

The sample was comprised of study casts of five hundred and twenty subjects (231 males and 289 females with a mean age of 15.4 ± 1.02 years). All subjects had permanent dentition with normal occlusion. A mathematical method associated with a polynomial function of 6th degree was employed to assess the dental arch forms. The resultant arch forms were classified into 5 groups for both the maxilla and mandible utilizing a computer software with special code designed for this study. Each group was subdivided into 3 subgroup sizes namely: small, medium, and large.

Results

Catenary arch form was found in 47% and 41.2% (p ˂ 0.01) of maxilla and mandible arch forms, respectively. Form 2 (which is halfway between ellipse and U-shaped arch form) was found in 27.7% and 26.7%. Medium size arch form was found in 55.4% of the maxillary and 65.6% of the mandibular arch forms.

Conclusion

Catenary arch form was the most prevalent arch form, followed by wide elliptical form. The other forms, which included tudor arch, tapered equilateral and quadrangular forms were less frequent. Regarding size, the medium size was the most prevalent among the studied samples.

Evaluation of Growth and Development of Late Mixed Dentition Upper Dental Arch with Normal Occlusion Using 3-Dimensional Digital Models

Objective

The purpose of this study was to observe the three-dimensional growth and development of the maxillary arch in 10-year-olds with normal occlusion during the late mixed dentition stage.

Methods

Forty-four 10-year-old students (22 males and 22 females) who had normal occlusion during late mixed dentition were selected from an elementary school in Beijing, China. Once per year for three consecutive years, a dental cast was obtained from each subject, and the cast was scanned with a 3D digital scanner (R700 3D). The three-dimensional measurements of the maxillary dental arch and the inclination of the bilateral maxillary first molars were obtained from the digital model.

Results

The upper anterior arch length (UAAL), upper total arch length (UTAL), upper inter primary or permanent canine width (UICW), upper intermolar width (UIMW), and upper dental arch length (UDAL) increased by 0.959 mm, 0.583 mm, 0.955 mm, 1.462 mm, and 2.46 mm, respectively, over the two years (P < 0.001). UR6BL and UL6BL decreased by 4.416° and 7.133°, respectively, over the two years (P < 0.001). The values of the UICW and UIMW were 1.67 mm and 1.86 mm, respectively, larger in males than in females at 12 years old (P < 0.01). The change in the UTAL was 0.431 mm greater in males than in females over the 2 years (P < 0.05).

Conclusion

The UAAL, UTAL, UICW, UIMW, and UDAL in 10- to 12-year-olds with normal occlusion increased with age. The buccolingual inclination of the bilateral maxillary first molars inclined to the palatal side with age. The UICW and UIMW were larger in males than in females at 12 years old. The male UTAL increased more than the female UTAL over the 2 years.