Analysis of dimensions and shapes of maxillary and mandibular dental arch in Korean young adults

Relationship between Nutrition and Development of the Jaws in Children: A Pilot Study

Craniofacial growth and development have been shown to be influenced by various environmental factors that impact child development. This study aims to analyze the different patterns of feeding during early childhood, starting from birth, and assess the variability of nutrition during the first stage of childhood, along with the habits developed, to study their impact on jaw development. The study was conducted on a sample of twenty-five patients aged 3 to 5, following approval from the ethics committee of the Catholic University of Valencia. Informed consent was obtained from the fathers, mothers, and/or legal guardians, who were administered surveys on habits and diet. Cephalometric measurements within the parameters of ideal occlusion were subsequently taken. While previous studies examined this subject, the findings are challenging to evaluate. However, this study identified significant associations (p = 0.001) between clinical measurements and children's eating habits. The growth and development of the craniofacial cavity are influenced by multiple factors, including a child's diet and habits. Nonetheless, further research is required to determine whether diet can be considered a determining factor in proper jaw growth.

Predictor Mandibular Dentoalveolar Features on the Occurrence of 1-Rooted/C-Shaped Mandibular Second Molar Teeth

OBJECTIVE

This study aimed to examine the mandible form features of the mandible, such as inter-second molar width, anteroposterior length, arch perimeter length, arch breadth, corpus height/width in the mandibular second molars (MnSM) region, and arch form, and the relation for the occasion of the 1-rooted/C-shaped.

METHODS

The study analyzed cone-beam computed tomography images of 215 male and 215 female Turkish patients to determine the prevalence of 1-rooted and C-shaped MnSM. Mandibular dentoalveolar characteristics of individuals with bilateral (1R-1R group) and unilateral (1R-2R group) 1-rooted MnSM were examined and compared with those with bilateral 2-roots (2R-2R group) MnSM. Statistical tests were performed using Chi-square, one-way ANOVA, Tukey, and binary logistic regression analysis at the 5% significance level.

RESULTS

The prevalence of 1-rooted and 1-rooted/C-shaped MnSM was 12.79% and 9.65%, respectively. Root fusion was more commonly present in females (p<0.05). In the 1R-1R group, the anteroposterior length was shorter than in the 2R-2R group (p<0.05). There was no difference between the groups for other features (p>0.05).

CONCLUSION

Although the study found a shorter anteroposterior length in the 1R-1R group, no feature was a predictive variable for 1-rooted/C-shaped MnSM.

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.

Developing a three-dimensional statistical shape model of normal dentition using an automated algorithm and normal samples

OBJECTIVES

The statistical shape model (SSM) is a model of geometric properties of a set of shapes based on statistical shape analysis. The SSM develops an average model of several objects using an automated algorithm that excludes the operator's subjectivity. The aim of this study was to develop a three-dimensional (3D) SSM of normal dentition to provide virtual templates for efficient treatment.

MATERIALS AND METHODS

Dental casts were obtained from participants with normal dentition. After acquiring the 3D models, the SSMs of the individual teeth and whole dental arch were generated by an iterative closest point (ICP)-based rigid registration and point correspondences, respectively. Then, the individual tooth SSM was aligned to the whole dental arch SSM using ICP-based registration to generate an average model of normal dentition.

RESULTS

The generated 3D SSM showed specific morphological features of normal dentition similar to those previously reported. Moreover, on measuring the arch dimensions, all values in this study were similar to those previously reported using normal dentition.

CONCLUSIONS

The 3D SSM of normal dentition may increase the diagnostic efficiency of orthodontic treatments by providing a visual objective. It can be also used as a 3D template in various fields of dentistry.

CLINICAL RELEVANCE

Our SSM of normal dentition provides both quantitative and qualitative information on the 3D morphology of teeth and dental arches, which may provide valuable information on 3D virtual-setup, bracket fabrication, and aligner treatment.

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.

Associations of sagittal malocclusions with dental arch characteristics and crowding in Northern Finland Birth Cohort 1966

OBJECTIVE

To analyse the associations between the widths and forms of dental arches, malocclusions and crowding in middle-aged adult population.

MATERIALS AND METHODS

The study material is part of the Northern Finland Birth Cohort 1966 (NFBC1966); the subjects were examined at the age of 46 years. A total of 781 adults with full dentition and no orthodontic treatment history were included. Overjet, overbite, cross-bite and scissor bite were examined during clinical examination. The widths and forms of dental arches, molar relationships and crowding were measured using three-dimensional (3D) dental models.

RESULTS

Dental arches were significantly larger in males than in females. Class II (CII) occlusion and increased overjet (≥6 mm) were associated with narrow maxilla (P < .001, P < .05 respectively). Subjects with lateral cross-bite had significantly narrower maxilla and wider mandible (P < .05) than subjects with normal lateral occlusion. In subjects with CII occlusion, square or tapered maxilla and tapered or ovoid mandible were significantly more frequent compared to subjects with Class I (CI) occlusion (P < .05). CII occlusion was significantly associated with crowding in the maxilla (P < .01).

CONCLUSION

Narrow and tapered-shaped maxilla was related to CII occlusion, which was associated with dental crowding in the maxilla. Malocclusions were more likely to be found together with other malocclusions than alone.

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.