Factors influencing different types of malocclusion and arch form-A review

Elucidation of Factors Affecting Anterior Occlusion in Primary Dentition Based on the Japan Environment and Children's Study

Background/Objectives: Malocclusion in primary dentition affects permanent dentition. However, the factors contributing to malocclusion in the oral cavities of children have not been fully elucidated. We hypothesized that environmental factors affect malocclusion in the primary dentition of the Japanese population and aimed to identify factors associated with anterior occlusion in primary dentition. Methods: The study involved 3793 parent-child pairs from the Miyagi Regional Centre as part of a supplementary survey to the Japan Environment and Children's Study, a cohort study. A questionnaire assessing oral development and environmental factors was administered to parent-child pairs who consented to participate. Parents assessed anterior occlusion when their children were 3.5 years old. Results: The maxillary primary central incisors tended to erupt earlier in the open bite group. Significantly more children in this group were breastfed until 1 year and drank ionic beverages at 1.5 years. In addition, thumb sucking or pacifier use was significantly common at 2 years of age. A correlation was observed between the mother's body mass index (BMI) before and after pregnancy and anterior occlusion. Conclusions: In the open bite group, the occlusion status of the anterior teeth at 3.5 years of age showed distinctive results influenced by the eruption period of the primary anterior teeth, oral habits, intake of sweetened beverages, and maternal BMI. These findings suggest that parental observation could be useful for screening children for malocclusion until the eruption of permanent dentition.

Orthodontic Treatment Need and Its Relation to Gender, Oral Hygiene, and Age Range in a Mexican Population

Introduction Malocclusion, a prevalent oral health concern, significantly impacts both functional abilities and psychosocial well-being. The Dental Aesthetic Index (DAI) is widely used to assess malocclusion severity and orthodontic treatment needs. This study aims to evaluate the prevalence of orthodontic treatment needs based on the DAI in a Mexican population, considering factors such as gender, oral hygiene, and age range. Materials and methods This retrospective observational study analyzed 639 patient records from the Orthodontics and Dentomaxillofacial Orthopedics postgraduate program at the Autonomous University of San Luis Potosí, San Luis Potosí, Mexico. The DAI was used to assess malocclusion severity, and patients were classified into four categories based on their scores. Data on gender, oral hygiene, and age were also collected and analyzed. Results The results showed no significant association between DAI levels and gender, oral hygiene, or age range. However, a significant association was found between missing teeth and higher DAI scores (OR = 8.9), maxillary irregularity (OR = 8.6), and open bite (OR = 4.9). The prevalence of severe malocclusion (DAI ≥ 36) was notably high, affecting over 50% of the study population. Discussion The findings align with previous studies that highlight the influence of structural irregularities such as open bite and maxillary irregularities on severe malocclusion. While no significant associations were found with gender, oral hygiene, or age, the high prevalence of severe malocclusion underscores the need for early orthodontic intervention in Mexican populations. Conclusion This study demonstrates a high prevalence of severe malocclusion in a Mexican population and highlights the importance of addressing structural dental irregularities to prevent long-term complications. These findings emphasize the need for accessible orthodontic care and early screening programs.

Impact of malocclusion and oral habits on oral health-related quality of life and sleep disturbance in young adults : A cross-sectional study

PURPOSE

The aim of this study was to investigate the impact of malocclusion and oral habits on oral health-related quality of life and sleep disturbance in young adults.

METHODS

A cross-sectional study was conducted with a sample of 213 young adults aged 18-30 years. Dental occlusion data were assessed through clinical examination. A questionnaire was used to collect data on oral habits. Outcomes were collected using the Oral Health Impact Profile (OHIP-14) and Mini Sleep Questionnaire.

RESULTS

Anterior open bite (adjusted odds ratio [OR] = 2.41, 95% confidence interval [CI] = 1.02-5.67, p = 0.044), swallowing disorders (adjusted OR = 2.39, 95% CI = 1.13-5.05, p = 0.022), and sleeping on hands were associated with a negative impact on oral health-related quality of life. Females (adjusted OR = 2.61, 95% CI = 1.10-6.17, p = 0.029), teeth grinding (adjusted OR = 2.78, 95% CI = 1.08-7.14, p = 0.034), biting lips or cheeks (adjusted OR = 4.28, 95% CI = 1.49-12.29, p = 0.007), and self-perception of need for orthodontic treatment (adjusted OR = 7.88, 95% CI = 2.12-29.30, p = 0.002) were associated as a risk for sleep disturbances.

CONCLUSION

The findings suggest that oral habits and some types of malocclusions can impact oral health-related quality of life. In addition, sleep disturbances were associated with a greater need for orthodontic treatment and a habit of grinding teeth in young adults.

Effect of a Novel 'Scan Body' on the In Vitro Scanning Accuracy of Full-Arch Implant Impressions

OBJECTIVE

This in vitro study aimed to determine whether a newly designed arcuate scan body can improve intraoral scanning accuracy for implant rehabilitation of edentulous jaws.

MATERIAL AND METHODS

A master model containing 4 implant abutment replicas was fabricated and digitized with different scan bodies using an intraoral scanner. Four types of scan bodies were evaluated: original scan bodies (group OS), computer-aided design and computer-aided manufacturing (CAD/CAM) scan bodies without extension (group CS), CAD/CAM scan bodies with straight extension (group CSS), and CAD/CAM scan bodies with arcuate extension (group CSA). Conventional splinted open-tray impressions (group CI) were used as controls. The master model and the poured casts were digitized using a laboratory scanner. Impressions were repeated 10 times each in 5 groups. Scans in standard tessellation language format were exported to reverse engineering software and root mean square (RMS) values were used for trueness and precision assessments. In each group, 45 RMS values were acquired for precision evaluation and 10 RMS values were obtained for trueness assessment. Statistical evaluation was performed with the Kruskal-Wallis test and Dunn-Bonferroni test (α = 0.05).

RESULTS

The median trueness values were 41.40, 55.95, 39.80, 39.75, and 22.30 μm for group OS, CS, CSS, CSA, and CI, respectively. CI showed better trueness than OS (P = .020), CS (P < .001), and CSS (P = .035). The median precisions for group OS, CS, CSS, CSA, and CI were 47.40, 51.50, 43.90, 25.20, and 24.60 μm. respectively. The precision of CSA and CI were higher than OS (P < .001), CS (P < .001), and CSS (P < .001). Between CI and CSA, there was no significant difference (P = 1.000).

CONCLUSIONS

For full-arch implant rehabilitation, the scan body with arcuate extension could improve the intraoral scanning precision and showed similar 3-dimensional discrepancy compared to conventional splinted open-tray impressions.

Correlation between oral muscle pressure and malocclusion in mixed dentition: a cross-sectional study

OBJECTIVE

To investigate the relationship between oral muscle pressure and malocclusion in the mixed dentition.

MATERIALS AND METHODS

Maximum tongue, lip and cheek pressure was measured using the Iowa Oral Performance Instrument (IOPI) in 3 patient cohorts: patients with (1) posterior crossbite, (2) class II relationship and (3) a control group of patients without malocclusion. Linear models were used to compare the mean differences in muscle pressure between groups, with correction for age and gender. The imbalance between lips and tongue and between lips and cheeks was calculated by the Delta z-scores of each group.

RESULTS

A total of 146 participants were included, 46 (mean age 8.71±0.85), 41 (mean age 11.74±1.17) and 35 (mean age 10.71±1.92) in groups 1, 2 and 3 respectively. Patients with malocclusion showed significantly higher lip and lower cheek pressure and imbalance favouring the lips over the tongue compared to controls. Class II,1 patients showed significantly higher tongue pressure than Class II,2. No differences were found in muscle pressure or imbalance between crossbite and Class II nor between crossbite types.

CONCLUSION AND CLINICAL RELEVANCE

These findings suggest that oral muscle pressure may be associated with malocclusion. This highlights the importance of functional diagnosis and its implications on the prevention and treatment of malocclusion, as well as on orthodontic stability.

Association between dental age and malocclusions: a systematic review

BACKGROUND

The evidence in the literature suggests that some skeletal or dental malocclusions are involved with dental development, resulting in advanced or delayed dental age (DA). The purpose of this systematic review was to investigate the association between DA and different types of malocclusions.

METHODS

The search was carried out on PubMed, Scopus, Web of Science, Virtual Health Library, and in the gray literature. Observational studies that evaluated the association between DA and sagittal, vertical, or transversal malocclusions were included. The quality assessment was performed using the Newcastle-Ottawa Scale (NOS). The data from primary studies were narratively synthesized. The certainty of evidence was evaluated using the GRADE approach. The study was conducted from August 2023 to October 2023.

RESULTS

One Thousand Nine Hundred Ninety-One records were identified in the initial search. Twenty (n = 20) studies were included. Most of the studies (n=15) presented a moderate quality according to NOS. Twelve studies evaluated the association between DA and sagittal discrepancies; eight studies evaluated vertical discrepancies, and only one study analyzed a transversal discrepancy. Demirjian's method for DA assessment was the most used among the studies. The primary studies observed that patients of both sexes presenting a vertical growth pattern and males with skeletal Class III malocclusion tend to have advanced DA. The study that investigated transversal malocclusion found that unilateral posterior cross-bite is associated with delayed DA. The certainty of evidence was very low for all outcomes evaluated.

CONCLUSION

DA may be associated with the type of malocclusion. It is suggested that DA can be used as an initial diagnostic tool in orthodontics. Future well-designed studies should be performed in order to investigate the association between DA and different types of malocclusions in more detail.

TRIAL REGISTRATION

This study was registered in the PROSPERO database (CRD42023454207).

Craniocervical posture in patients with skeletal malocclusion and its correlation with craniofacial morphology during different growth periods

The association between craniocervical posture and craniofacial structures in the various sagittal skeletal malocclusion during different growth stages has been the focus of intense interest in fields of orthodontics, but it has not been conclusively demonstrated. Thus, this study aimed to investigate the association between craniofacial morphology and craniocervical posture in patients with sagittal skeletal malocclusion during different growth periods. A total of 150 from a large pool of cephalograms qualified for the inclusion and exclusion were evaluated and classified into three groups according to the Cervical Vertebral Maturation (CVM) by examining the morphological modifications of the second through fourth cervical vertebrae, each group consisted of 50 cephalograms. In each growth period, for the comparison of head and cervical posture differences among various skeletal classes, the radiographs were further subdivided into skeletal Class I (0° < ANB < 5°, n = 16), skeletal Class II (ANB ≥ 5°, n = 18), and skeletal Class III (0° ≤ ANB, n = 16) on the basis of their ANB angle. There was no significant difference in gender (P > 0.05). Some variables were found to be significant during pubertal growth and later in patients with sagittal skeletal malocclusion (P < 0.05). Most indicators describing craniocervical posture were largest in skeletal Class II and smallest in skeletal Class III during the peak growth periods and later. Cervical inclination variables were greater in skeletal Class III than in skeletal Class II. Variables of craniofacial morphology and craniocervical posture are more correlated during the pubertal growth period and later in patients with sagittal skeletal malocclusion. A tendency is an indication of the close interrelationship that a more extended head was in skeletal Class II while a flexed head was in skeletal Class III. Nevertheless, with the considerations of some limitations involved in this study, further longitudinal studies with large samples are required to elucidate the relationship clearly.

Prevalence of malocclusions under conditions of prolonged introduction of systemic fluorides in variable concentrations: Literature review

The pathogenesis of malocclusions, which are common among the population of  all  countries, is  well represented in the professional literature. The occurrence of  malocclusions is associated with genetic and various environmental factors. Among the latter, fluorides which affect the prevalence of some dental diseases are of particular interest. However, there are few publications reflecting the frequency of malocclusion among the population in the regions with different levels of fluoride in drinking water. This problem seems to be significant in the context of the increasing impact of fluorine compounds on human health, including dental health.

The aim of the study. To analyze the literature on the frequency of malocclusion among the population living in conditions of variable fluoride content in drinking water. A manual search of domestic and foreign literature was performed in the search databases PubMed, Medline and Google Scholar. From the initial list of publications, eighteen articles that met the inclusion criteria for the study were selected for analysis. We revealed significant variability of the research results. Some authors note a higher prevalence of malocclusions among the population under conditions of increased fluoride intake, others note a lower one, and still others did not reveal any differences between the values obtained in both samples. Most of the assessed publications did not methodologically meet modern international standards, and therefore were of little evidence.

The literature data do not provide grounds for an unambiguous assessment of fluorine compounds as an environmental factor that indirectly affects the process of occlusion formation in humans and animals.

The review did not allow to make a definitive conclusion on the possible impact of  systemic fluorides on the prevalence and pattern of malocclusion in humans and animals. It requires the implementation of studies that comply with the principles of evidence-based medicine. 

Temporomandibular Joint and Otitis Media: A Narrative Review of Implications in Etiopathogenesis and Treatment

Otitis media (OM) and its recurring (rAOM), effusive (OME), and chronic forms, represent a frequent clinical challenge. The middle ear, the mandible, and the temporomandibular joint (TMJ) share several embryological and anatomical connections. Despite that, the role of mandibular malposition and TMJ dysfunction is frequently overlooked in the management of otitis media. In this narrative review, we present current evidence supporting the etiopathogenetic role of a dysfunctional stomatognathic system in the onset of OM and the effectiveness of orthognathic treatment in preventing rAOM and OME. In particular, a focus on the influence of TMJ on Eustachian tube function is provided.