Journal of Orthodontic Science最新文献

Objective: This retrospective study aimed to investigate the association between orthodontic treatment and development of temporomandibular disorders (TMDs) in pediatric patients.

Methods: This study analyzed 122 pediatric patients (age 10-18 years) who underwent orthodontic treatment. The inclusion criteria included comprehensive orthodontic records and substantial clinical documentation, while the exclusion criteria targeted preexisting TMDs or syndromes affecting the temporomandibular joint. Demographic details, treatment characteristics, and radiographic analyses, including standardized cephalometric measurements, were recorded. Clinical records were systematically reviewed for signs and symptoms of TMD, with categorization based on TMD severity using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD).

Results: Demographic characteristics revealed a mean age of 14.2 years, with a sex distribution of 36.9% males and 63.1% females. Pain, clicking/popping sounds, and limited jaw movement were reported by 23.0%, 16.4%, and 12.3% of the patients, respectively. TMD severity classification showed that 73.8% had no symptoms, 20.5% had mild symptoms, 4.1% had moderate symptoms, and 1.6% had severe symptoms. Statistical analyses revealed a significant association between TMD symptoms and sex (P = 0.023). Correlations among TMD severity, treatment duration (P = 0.036), and cephalometric changes were observed. Radiographic findings showed a moderate correlation with the gonial angle (r = 0.42) and a strong correlation with the condylar position (r = 0.58).

Conclusion: This study provides insights into the complex relationship between orthodontic treatment and TMD development in pediatric patients. These findings suggest potential associations between treatment characteristics, cephalometric changes, and TMD symptoms.

Objective: With good communication and information retention being key aspects of valid consent, this study aimed to assess adult patient information recall immediately after an orthodontic consultation.

Materials and methods: Adults interested in bracket-based or clear aligners were invited to take part at a single private dental practice. A 45-minute consultation with one of three general dental practitioners (GDPs) primarily providing orthodontics took place. A participant self-completed questionnaire tested recall of 20 items from the consultation. Demographics such as gender, age, level of English, education level, previous orthodontic experience and having a close family member or friend who had orthodontic treatment were also recorded.

Results: Forty-two participants completed the questionnaire, and the information recall rate was 75% (mean score = 15). Three of the 42 participants recalled all 20 items. No statistically significant differences (P < 0.05) were found between information recall and any demographic variable, however, older participants (36 years and over) scored less (mean = 13.83) than participants 18-25 years (mean = 15.6).

Conclusions: A quarter of information provided during an orthodontic consultation with a GDP in a private dental practice cannot be recalled immediately afterwards by patients and so it is recommended that any verbal or visual information is always supplemented with written information.

Objectives: This in vitro study aimed to determine how three different energy drink types affected the force decay of three distinct brands of clear, short elastomeric chains over various time intervals.

Materials and methods: In this study, 600 pieces of clear, short elastomeric chains from three brands were examined. The initial force was measured immediately using a digital scale and after 1, 7, 14, 21, and 28 days. These intervals followed immersion in the respective energy drink for 5 minutes twice daily. Using one-way ANOVA and Tukey's HSD tests, the percentage of force decay was computed and compared across the different elastic brands, time intervals, and energy drinks.

Results: The force degradation of various elastic brands immersed in different energy drinks increased over time, following a similar pattern of decay. By the end of the fourth week, there were highly significant differences in the force decay percentage, varying from 68% to 83%.

Conclusions: Considering the effects of brands, duration, and energy drinks, all the evaluated brands exhibited similar patterns of force decay, with highly significant differences noted. The force decay in Coca-Cola Energy and Fire ball drinks is relatively higher than in other beverages.

Context: Assessing and monitoring treatment quality within graduate courses are vital for maintaining high standards and addressing areas needing improvement. In this study, we evaluated the treatment quality delivered by measuring the total scores obtained from the comprehensive clinical assessment (CCA) index and the objective grading system (OGS) index.

Aims: This study aimed to evaluate the quality of orthodontic treatments administered by graduate students by using the CCA index and OGS index.

Settings and design: The research was carried out at the Orthodontic Department of Mashhad School of Dentistry, focusing on a cross-sectional analysis of orthodontic treatments administered by graduate students.

Methods and material: The study randomly selected 36 cases from the department's archives and evaluated them through pre- and post-treatment analyses, including radiographs, photographs, and dental casts. The evaluation employed the CCA and the OGS indices.

Statistical analysis used: Data analysis was performed using the Spearman and Mann-Whitney tests.

Results: The CCA correlated with the patient's age and gender and was statistically significant (P = 0.007 and P = 0.010, respectively). The CCA index was substantially associated with treatment duration (P = 0.032 a). There was no significant relationship between OGS and CCA (P = 0.223). The mean of post-treatment OGS was 18.97. All criteria of OGS and the overall score were improved significantly (P < 0.001).

Conclusions: The results of this study suggested that orthodontic treatment results provided by the investigated program have high scores and meet high standards of the CCA and OGS indices.

Objective: To determine the effect of the nose and chin on the cephalometric lip profile.

Methods and material: The pre-treatment lateral cephalograms of 177 adult patients with no history of orthodontic treatment were manually traced. The sample size was divided into three vertical and horizontal groups using angle ANB and MMA to assess the difference in nose and chin forms. The horizontal and vertical groups were analyzed using One-way ANOVA and Kruskal-Wallis. The Independent sample t-test and Mann-Whitney U were used for comparison between the two genders. The correlation of nose and chin with E, S line, and nasolabial angle was done using the Spearman correlation coefficient while the effect was assessed using linear regression analysis.

Results: Among the nasal variables, columellar length inversely affects the linear position of the upper lip and this was statistically significant. The nasolabial angle is also affected by the inclination of the nasal base and this was statistically significant. The linear distance of the soft tissue chin in relation to the maxilla has the most effect on the position of the upper lip. It is notable that all hard and soft tissue chin variables inversely affected the linear position of the upper and lower lips.

Conclusions: The quantitative measure of the effect of the nose and chin on lips is important as it allows clinicians to determine the overall effect of adjunctive procedures at pretreatment levels. Thus, corrective procedures such as rhinoplasty or genioplasty can be done at pre-orthodontic treatment stages to create a better treatment plan for patients.

Aim: The aim of this study was to make a laboratory assessment of pH influence on the kinetics of the release of nickel ions in artificial saliva.

Methods and material: In this study, 15 basic orthodontic appliances are immersed in 15 polyethylene tubes each containing 40 ml of artificial saliva. Tubes were divided into three sub-groups of 5 tubes depending on the pH: pH 5, pH 7 and pH 8. The release of nickel ions was measured using atomic absorption spectrometry in a sample of 5 ml of artificial saliva taken one hour, four hours and one hundred and sixty-eight hours after immersion in a water bath at 37°.

Statistical analysis used: Significance threshold P was set at 0.05. A Student T test and the 2-way Anova test (with a Bonferoni post-test) were used respectively to compare the means.

Results: The neutral pH causes a low release of nickel ions. The release kinetics of nickel ions is minimal for neutral pH, it increases when pH varies. After one hour of immersion, the nickel released did not reach the spectrometer quantification threshold as for neutral and acid pH. The alkaline pH causes an average release of nickel ions from the beginning without kinetic variation. As time passes (T3), the acidic pH causes more nickel ions release through a succession of oxidation-reduction reactions. After 168 hours, the average mass of nickel released is 0.30 µg for pH 7, 1.35 µg for pH 8 and up to 2.85 µg for pH 5.

Conclusions: Quantities released did not reach nickel toxicity threshold in humans. Orthodontists must consider the potential risk of hypersensitivity due to nickel in fixed orthodontic appliances.

Context: The mandibular canal (MC) is an essential landmark that should be considered before any surgeries. Therefore, accurately assessing the location and characteristics of the MC in cone beam computed tomography (CBCT) imaging is very important.

Aims: To determine the characteristics of the MC in relation to adjacent anatomical structures in CBCT projections.

Settings and design: The convenience sampling method.

Methods and material: This was a retrospective study of 112 CBCT images of Vietnamese patients aged 18 to 69 years, taken for clinical indications between 2018 and 2023. The evaluation was carried out by comparing and arranging the anatomical structures of different planes in three-dimensional space to assess and measure relevant dimensions.

Statistical analysis used: Independent samples T-test.

Results: The average diameter of the MC from the apex of the second premolar to the distal apex of the second molar, if there were no missing teeth in this segment, was 2.58 ± 0.52 mm (right) and 2.55 ± 0.54 mm (left). If there were a missing tooth in this segment, the measurements were 2.51 ± 0.79 mm (right) and 2.47 ± 0.45 mm (left). The difference between the two sides regarding the presence or absence of a missing tooth was not statistically significant.

Conclusions: The precise localization of the MC related to the tooth apex and the diameter of the MC can vary in each person. CBCT indications should be considered when establishing treatment planning to avoid damaging the inferior alveolar nerve in the MC.

Background: Bullying has a lasting effect on young, vulnerable minds, especially among school-aged youngsters. With the help of this study, we intended to examine how physical and dentofacial characteristics contribute to bullying among kids and how it affects their academic performance.

Methods: This retrospective cross-sectional study consisted of a self-reported anonymous, pretested questionnaire divided into three major domains, with due institutional ethical clearance being obtained before the study's commencement.

Results: The study population consisted of 269 schoolchildren, with 49.8% being males and the majority (55.0%) residing in Ajman. Among the schoolchildren, 35.7% reported being victims of bullying. The majority of bully victims (27.1%) skipped school because of bullying. Additionally, 64.3% of the students had a nickname, primarily used by siblings, and approximately half of the bully victims disliked their nicknames. In terms of happiness, 45.0% of students were neither happy nor unhappy in classes, while 10.8% were very unhappy. Outside of school, 56.9% of participants were very happy, and only 1.1% were very unhappy. Most students (58.7%) did not believe that bullying harms their grades, while 19.7% believed it does. Furthermore, 71.7% of students did not experience bullying due to good grades or showing interest in schoolwork.

Conclusion: Based on results, physical and dentofacial features in bullying among schoolchildren and its impact on school performance, sociodemographic patterns, and factors associated with bullying victimization highlight the need for targeted interventions and preventive strategies to address this issue. Thus, can create a safe and supportive school environment that promotes the well-being and academic success of all schoolchildren.

Objective: To evaluate and compare the skeletal and dental treatment effects of Class II malocclusion cases using skeletally anchored Forsus (miniscrew-anchored FRD or miniplate-anchored FRD), with conventional Forsus FRD.

Materials and methods: Unrestricted electronic search of six databases and additional manual searches were performed up to July 2023. Randomized controlled trials having one treatment arm with skeletal anchored Forsus FRD in treatment of Class II malocclusion and another matched treatment group treated with conventional Forsus FRD were included in this review. Risk of bias assessment was performed using Cochrane's Risk of Bias Tool. No restrictions were set concerning treatment duration, or the cephalometric analysis used. Skeletal and dentoalveolar outcomes data were extracted by two authors independently.

Results: Three studies using miniscrews as means of skeletal anchorage were evaluated and qualified for the final review and meta-analysis. Three other studies using miniplates were considered in the systematic review but were not qualified for a meta-analysis. The data gathered from the miniscrews anchored FRD papers included a total of 93 Class II patients (46 treated with miniscrew-anchored Forsus FRD, 47 treated with conventional Forsus FRD). The meta-analysis showed a statistically significant reduction in the SNA angle in favor of miniscrew-anchored Forsus FRD (mean difference: -0.26, CI: -0.50 to -0.02), a nonsignificant difference in the SNB (mean difference: 0.17, CI: -0.06 to 0.39), a statistically significant increase in the SN-MP angle in favor of miniscrew-anchored Forsus FRD (mean difference: 0.53, CI: 0.06-1.00)-a statistically significant reduction in the L1-MP angle in favor of miniscrew-anchored Forsus FRD (mean difference: -2.12, CI: -4.96 to -2.12). Data from miniplate-anchored FRD included 31 Class II patients treated with mini plate anchored FRD. Although meta-analysis was not applicable to these studies, lower incisor inclination was observed to be less.

Conclusions: Based on the existing evidence, the use of skeletal anchorage could not enhance forward mandibular growth. However, miniscrew-anchored Forsus FRD could minimize mandibular incisor protrusion while miniplates could even retract the mandibular incisor position with a headgear effect on the maxilla.

Objectives: As patients are instructed to wear thermoplastic retainers for the rest of their lives, the durability of the materials is a critical factor in evaluating whether the expense is justified. This study examined the physical and mechanical properties of three different thermoplastic retainer materials before and after thermoforming (BT and AT).

Materials and methods: Clear Advantage Series I, Clear Advantage Series II, and Leone types were used, with each material having a thickness of 1 mm. The materials' tensile force, hardness, and water absorption tests have been measured for 90 thermoformed and 90 non-thermoformed specimens (30 specimens from each material).

Results: The tensile force, hardness, and water absorption values of all the materials differed significantly (P ≤ 0.05) BT. Additionally, the majority of the materials showed significant differences in water absorption, hardness, and tensile force (P ≤ 0.05) AT, except the Leone materials, and Clear Advantage Series I did not significantly differ in the case of hardness value. All studied materials showed an increase in hardness and water absorption AT (P ≤ 0.05). At the same time, all of the studied materials showed a significant decrease in tensile force after thermoforming.

Conclusion: Thermoforming increases the material's water absorption while decreasing its stiffness, affecting its mechanical and physical properties. Clear Advantage Series II (PP) stood out with superior flexibility, wear resistance, and minimal water absorption compared to other materials, highlighting its durability and superiority.