جستجوی مقالات مرتبط با کلیدواژه « malocclusion » در نشریات گروه « پزشکی »

Anterior crossbite is the most commonly observed developing malocclusion during the mixed dentition period. Dental crossbite occurs due to over-retained deciduous teeth or their delayed exfoliation, impacted or supernumerary teeth, pathologies present around the affected teeth, or dental trauma during the primary dentition period. Various removable and fixed appliances have been used in the literature for correction of crossbite depending on the patient's age, and space availability in dental arch.

This paper presents a case series of anterior crossbite cases corrected using a simple posterior bite plane appliance. This appliance is simple, easy to fabricate, and takes less time to correct the crossbite.

A posterior bite plane with a palatal plate could be an efficient solution for correction of anterior dental crossbite in the mixed dentition period. This chair-side fabricated appliance achieves correction quickly without harming the periodontal tissue. Developing malocclusions should be immediately identified by dentists to prevent complex treatment options in the future.

The Bolton analysis is commonly used by orthodontists. The Bolton ratios of different populations are significantly different from the standard values of Bolton. This study sought to examine the Bolton's anterior and overall ratios in various malocclusion types in Mashhad, Iran, in contrast to the Bolton’s standards.

This descriptive-analytical study was conducted on 240 study models of patients (121 males and 119 females) in four groups (n= 60 cases) of normal occlusion, Class I, Class II, and Class III. The mesiodistal dimensions of the teeth were measured twice using a digital caliper. The anterior and overall ratios of Bolton were calculated. Statistical analysis was conducted utilizing SPSS 18.0.

The mesiodistal width of the maxillary lateral incisors in normal occlusion cases was greater than that in Class I, Class II, and Class III malocclusions (P<0.05). Conversely, the mesiodistal width of the maxillary first and second premolars was the greatest in Class II and the smallest in Class III malocclusion (P<0.05). Correlation was not observed between dental ratios (anterior and overall) and gender or malocclusion groups (P>0.05). Furthermore, the anterior ratio was significantly higher than the Bolton's standard in Class I and III malocclusion groups (P<0.05). The normal occlusion group's overall ratio was significantly lower than the Bolton's original ratio (P<0.05).

Implementing the Bolton analysis in the population of Mashhad, Iran should be approached with caution.

The aim was to determine the effect of first premolars extraction with maximum incisor retraction on airway magnitude and hyoid bone position in cases with bimaxillary dentoalveolar protrusion.

Lateral cephalograms of patients with Class I skeletal and dental relationships were retrospectively recruited. Inclusion criteria were 15-30 years old patients having bimaxillary proclination who had undergone all first premolar extractions with maximum incisor retraction.  Patients with dentofacial anomalies, chronic mouth breathing and those who had undergone tonsillectomy or adenoidectomy were excluded. Pre-and post-treatment lateral cephalograms were digitally analyzed for airway measurements and hyoid bone position. Paired samples T-test was used for statistical analysis. P-value<0.05 was considered statistically significant.

A total of 33 patients, comprising 22 females and 11 males, with a mean age of 24.39 ± 6.92 years were included. Statistically significant differences were found in airway dimensions from pre-treatment to post-treatment; upper airway size between soft palate and posterior pharyngeal wall (SPP-SPPW) was reduced by 1.91mm (12.78%), at uvula & middle posterior wall (U-MPW) by 2.51mm (20.60%), at tongue base to posterior-inferior point on middle pharyngeal wall (TB-TPPW) by 3.39mm (24.26%) and vallecular to lower pharyngeal wall by 1.51mm (9.94%). The vertical position of hyoid bone also significantly reduced as indicated by inferior movement of hyoidale (H) by 4mm (3.8%). There was no significant changes in the horizontal position of the hyoid bone.

Premolar extraction with maximum retraction in bimaxillary protrusion cases can decrease the airway dimension and increase vertical position of hyoid bone.

 We aimed to assess the effect of finger-sucking, nail-biting, and salivary levels of growth hormone on the type of malocclusion among primary school students. 

This study was conducted among 10–11-year-old (4th and 5th class of the elementary schools) students in the center of Karbala city from February to June 2021 using a multistage cluster random sampling technique. Data related to oral habits were obtained using questionnaires, which were distributed among the students and collected the next day after being answered and signed by the parents. Unstimulated saliva samples were collected, and salivary levels of growth hormone were assessed using the enzyme-linked immunosorbent assay (ELISA) method. Data were analyzed via multinomial logistic regression using R software. 

The finger sucking was a significant predictor for class 2 malocclusion (p < 0.001). Night-time finger sucking was a significant predictor for class 3 malocclusion (p = 0.031). Salivary levels of growth hormone and nail-biting were not significant predictors for malocclusion (p ˃ 0.05). Also, finger sucking was a marginally nonsignificant predicator for class 3 malocclusion (p = 0.057). 

 Cross-sectional studies capture data at a single point in time, and they cannot establish a cause-and-effect relationship. More cohort studies are required to reach a conclusion about the effect of non-nutritive sucking habits such as finger sucking, nail-biting and salivary level of growth hormone on type of malocclusion.

Objectives :

This study aimed to assess the relationship of skeletal class of malocclusion with some radiomorphometric indices of the mandible in short-face patients.

Methods :

This cross-sectional study was conducted on 179 short-face patients between 17 to 30 years who sought orthodontic treatment during 2013 to 2020. The gonial and antegonial angles, and type and depth of antegonial notch were assessed bilaterally on traced panoramic radiographs. The correlation between radiomorphometric indices and class of malocclusion was analyzed using One-way ANOVA and Independent T-test by SPSS version 25 (alpha=0.05).

Results:

 The mean size of gonial angle was significantly different among the three classes of malocclusion (P<0.001), and the largest gonial angle was recorded in class III, and the smallest in class I patients. The mean size of antegonial angle and antegonial depth were not significantly different among the three classes of malocclusion (P=0.487). The difference in the mean size of gonial and antegonial angles was not significant between males and females (P=0.119, and P=0.176, respectively). However, the mean antegonial depth in males was significantly greater than that in females (P<0.001). Type I antegonial notch was more common in females than males at both sides. Age had no significant correlation with gonial angle, antegonial angle, or antegonial notch depth (P=0.422, P=0.737, P=0.392, respectively).

Conclusion:

 Facial growth pattern in short-face patients can be predicted with antegonial angle. Also there is significant correlation between skeletal class of malocclusion and the size of gonial angle.

The term Ponticulus Posticus (PP) refers to a complete or partial bony bridge on the vertebral artery that passes through the superior-lateral surface of the posterior arch of the atlas. This study was conducted with the aim of investigating the prevalence of ponticulus posticus in orthodontic patients referred to Mashhad Dental School.   

In this cross-sectional study, one thousand cephalograms were selected from the patients referred to the orthodontics department of Mashhad Dental School between 2017 and 2021. In lateral cephalogram images with appropriate quality, the type of malocclusion was determined using the AudaxCeph software (Audax d.o.o., Ljubljana, Slovenia). Then, the images were evaluated for the presence or absence of PP. For the statistical analysis, chi-square and t-test were used.   

In this study, 861 lateral digital cephalograms were analyzed. The overall prevalence of PP in the studied population was 17.5%. The prevalence of PP was higher in males than in females (P < 0.001).  The variables “presence of PP” (P = 0.056) and “type of PP” (P = 0.522) were found to be independent of age groups. Although class II subjects showed a higher prevalence of PP, skeletal malocclusion classes were not found to be correlated with the presence of PP (P = 0.104) nor with its types (P = 0.958).   

The current study is considered the primary study that provides data concerning the prevalence of PP in the East of Iran. Our study showed that PP was not rare in this region. More studies with 3D radiological examination are needed to increase the accuracy of diagnosing PP and its prevalence in Iran.

This study aimed to investigate the effect of growth modification treatments on oral health-related quality of life in adolescents aged 11 to 14 years with Class II malocclusion.

Eighty people participated in this case-control study. The case group (n=43) included adolescents with a history of Class II malocclusion treated with growth modification. The control group consisted of 37 adolescents with Class II malocclusion who were not treated. Both groups were given a translation of the Child Perception Questionnaire (CPQ), measuring the quality of life in four domains: oral symptoms, functional limitations, psychological health, and social well-being. Data were statistically analyzed by SPSS software and a significance level of 0.05 was considered.

The oral health-related quality of life of the case group was better than the control group in all areas although this difference was not statistically significant (P=0.204).

The oral health-related quality of life between two groups was not different; however, the difference in mental health components between the two groups was clinically negligible.

The bite force changes due to alterations in the lever system of the jaw following orthognathic surgery. This study aimed to assess the changes in the maximum bite force of skeletal Class II patients between 18-30 years after orthognathic surgery compared with the preoperative state.

This inception cohort study evaluated 17 patients with skeletal Class II malocclusion (mandibular deficiency) and normal vertical dimension between 18-30 years who underwent mandibular advancement surgery. The maximum bite force on the mandibular first molars was measured preoperatively and at 6 weeks, and 3 and 6 months, postoperatively. The overjet and overbite were also measured on diagnostic casts. Data were analyzed by the Shapiro-Wilk test, Mauchly’s test, the Greenhouse–Geisser correction, and the Spearman and Pearson’s correlation coefficients. 

The mean maximum bite force preoperatively was significantly higher than that at 6 weeks (P<0.001), 3 months (P<0.001), and 6 months (P<0.001), postoperatively. No significant difference was noted in the mean bite force in the right and left sides of the jaw (P=0.589). The overbite and maximum bite force were not significantly correlated in the right (P=0.181) or the left (P=0.134) side, preoperatively. The overjet had no significant correlation with the maximum bite force in the right (P=0.881) or the left (P=0.677) side, preoperatively.

Mandibular advancement surgery in skeletal Class II patients with mandibular deficiency decreases the maximum bite force in the first 6 months, postoperatively.

Given the extensive number of surgical procedures available for correcting CL III anomalies, the present study was conducted in a private clinic from 2014-15 to determine whether simpler orthodontic and surgery techniques could be an alternative to the conventional techniques for resolving such functional and aesthetic problems.

The present study was conducted using a sequential before-after design on patients with mild to moderate maxillary deficiency. First, the study records including casts, photographs and radiographs were prepared. A Hyrax appliance with two tongue plates was then constructed for the patient before the Surgically Assisted Rapid Maxillary Expansion (SARME) osteotomy. The surgical technique involved local anesthesia without general anesthesia and the Lefort I osteotomy was performed without down fracture and without the manipulation of the pterygomaxillary suture. The transverse problem was corrected by unscrewing the Hyrax, and the tongue force exerted on the back of the tongue plate corrected the sagittal maxillary deficiency. To evaluate the efficacy of this appliance, the mean changes to the cephalometric indicators before and after the treatment were examined, and the paired t-test was used for the statistical analysis.

The present study was conducted on 11 patients (9 females and 2 males). The mean changes indicated a significant increase in Articular Angle, Jarabak index, and a significant decrease in L1 - NB (mm), L1 - NB (º) and Saddle Angle. The other indicators had either decreased or were not changed.

Using a Hyrax appliance combined with a tongue plate after a SARME surgery is effective in correcting CL III anomalies associated with maxillary deficiency.

The aim of this study was to determine the level of awareness and knowledge of family physicians regarding oral and maxillofacial evaluations and orthodontic treatment.

The survey was designed as 21 questions and sent to family physicians in Turkiye. The participants were asked about their age, gender, place of work, years of experience, regions evaluated during the routine examination, and level of orthodontic awareness and knowledge.

A total of 400 family physicians completed the survey. There was a significant difference in the referral rate of family physicians working in university hospitals (p<0.01), years of experience (p<0.001), whether evaluating the head and neck region (p<0.05), and the jaw positions during a routine examination (p<0.001) and for those who performed an intraoral examination and who checked dental crowding (p<0.001). When evaluating the head and neck region and dental crowding in routine examinations, a significant difference was found in the number of experienced family physicians (p<0.05).

Awareness of the facial profile and having orthodontic knowledge was relatively high in the family physicians who participated in our study; however, their number of oral and maxillofacial evaluations were found to be low in routine examinations. It would be beneficial to organize seminars, conferences, and symposiums to increase the awareness and knowledge of family physicians on the oral and maxillofacial region and how to conduct efficient orthodontic evaluations.

The aim of this study was to assess the association between malocclusion, self-perception, self-esteem, and socio-demographic factors among primary schoolchildren in Dar es Salaam, Tanzania.

This was an analytical cross-sectional study that involved children aged 10-12 years from primary schools in Dar es Salaam. A questionnaire was used to obtain information about the participants’ socio-demographics, self-perception and self-esteem. Clinical examination was done to determine their occlusal statuses. Data were analyzed using SPSS software (version 22.0), and Chi-square test and logistic regression model were used to assess statistically significant differences between variables. P<0.05 was considered as significant.

A total of 620 schoolchildren participated in this study. The overall prevalence of malocclusion was 66.5%. Undesirable self-perception was reported in 34.0% and self-esteem issues in 30.0% of the schoolchildren. Significantly, many participants with less educated fathers had malocclusion compared with their counterparts (p=0.002). Furthermore, most children with malocclusion perceived themselves negatively and reported lower self-esteem compared with those who had no malocclusion (78.7% vs. 21.3%, p=0.000 and 75.8% vs. 24.2%, p=0.001, respectively). In the logistic regression model, the presence of malocclusion remained as a significant determinant of schoolchildren perceiving themselves negatively and reporting lower self-esteem (OR: 2.4, CI: 1.62-3.54, p= 0.000 and OR: 1.82, CI: 1.23-2.7, p= 0.003, respectively).

The presence of malocclusion was associated with children's negative self-perception and lower self-esteem. Malocclusion prevention and early interventions in children are highly recommended.

The outcome of orthodontic treatment depends on the malocclusion and the ratio of the size of the upper and lower teeth. The aim of this study was to evaluate the discrepancy of tooth crown size in different groups of malocclusions.

In this cross-sectional study, 165 patients referred to the Orthodontic Department of Babol School of Dentistry were randomly selected. The samples were divided into three skeletal malocclusion groups (55 in each group) according to the ANB angle. The level of anterior and total Bolton ratio in the cases was calculated, and the deviation from normal value of anterior and posterior Bolton was calculated. The results were analyzed using the ANOVA and chi-square test. The significance level was set at p <0.05.

 The sample consists of 80 males and 85 females aged 12 to 25 years. The mean and standard deviation of the anterior tooth ratio were 79.06 ± 2.87 in Cl I, 79.23 ± 3.18 in Cl II, and 80.16 ± 3.71 in Cl III, and there was no significant difference between the mean anterior ratio between the malocclusion groups. The mean and standard deviation of the total Bolton ratio (TBI) were 91.3 ± 2.39 in Cl I, 91.6 ± 2.49 in Cl II, and 92.49 ± 2.64 in Cl III and the difference between the mean total ratio among the groups was statistically significant.

 Based on the results of this study between different groups of malocclusion, clinicians should consider the detailed examination of dental proportions in the diagnosis and treatment planning stage.

Objectives :

The decision regarding orthodontic tooth extraction or dental arch expansion is an important yet challenging topic in orthodontic treatment planning. However, studies in this respect are limited In Iran. This study aimed to assess the frequency of orthodontic tooth extractions and the role of malocclusion-related factors that affect the frequency of orthodontic extractions in a university setting during 25 years.

Methods :

This descriptive retrospective study evaluated 1,222 records of patients who underwent fixed orthodontic treatment in Shahid Beheshti Dental School from 1994 to 2018. The frequency of tooth extraction, type of malocclusion, and age and gender of patients were analyzed by the Chi-square test. The correlation of quantitative and qualitative variables related to occlusion (overjet, overbite, space discrepancy, cross-bite, A point–nasion–B point angle, mandibular plane angle, canine relationship, molar relationship, and the Curve of Spee) with orthodontic extraction was analyzed by the binary logistic regression. All statistical analyses were performed by SPSS version 21.

Results :

The frequency of orthodontic extraction decreased from 1994 (74.5%) to 2018 (41.6%). The highest frequency of orthodontic extraction (60%) occurred in class II division I malocclusion cases. Frequency of orthodontic extraction in the age group of 12-20 years was significantly higher than in other age groups (P=0.003). The odds of orthodontic extraction increased by an increase in overjet (P=0.036) and in class II malocclusion cases (P=0.05), and decreased by an increase in overbite (P=0.020).

Conclusion:

 Tendency to orthodontic extraction has decreased in contemporary orthodontics in Shahid Beheshti Dental School. In addition to the degree of dental crowding, the decision regarding orthodontic extraction also depended on overjet, overbite, and type of malocclusion.