Molar Relationship Research Articles

Upper airways changes associated with orthodontic molar distalization by Pendulum appliance in adolescent patients: a multicenter retrospective cephalometric study

ObjectivesThe purpose of this multicenter retrospective study was to perform a two-dimensional analysis of upper airway changes in adolescent patients following molar distalization with the Pendulum appliance.Materials and methodsThe study involved the cephalometric analysis of 88 patients, retrospectively categorized into two groups: skeletal Class II with a dental Class II molar relationship (36 patients, mean age 12.6 ± 1.1 years) and skeletal Class I with a dental Class II molar relationship (54 patients, mean age 12.3 ± 1.2 years). Changes were observed using lateral radiographs before (T0) and after Pendulum appliance removal (T1); treatment time averaged 7 months. Upper airways were subsequently analyzed by tracing lateral radiographs. The Shapiro-Wilk test showed a normal distribution of the data, therefore parametric tests were used for statistical analysis. Intragroup changes between T0 and T1 were evaluated using paired t-tests, and intergroup differences were assessed using independent student t-tests; statistical significance was set at 0.05.ResultsStatistically significant differences were observed in the skeletal measurements that characterized both groups, particularly in ANB and Wits appraisal, at T0 (P < 0.001). After molar distalization, Class I and Class II groups reported no statistically significant differences with changes almost equal to zero between timepoints (P > 0.05). Additionally, intergroup comparisons of airway changes at T1 did not show statistically significant differences (P > 0.05).ConclusionsThe Pendulum appliance does not significantly change the upper airway dimensions in Class I and Class II malocclusion patients, thereby minimizing potential respiratory risks.

Favourable dentoalveolar changes after lower premolar extractions for Class III camouflage with completely customized lingual appliances

BackgroundThe aim of the investigation was to evaluate if the inclination of the lower anterior teeth can be controlled reliably after lower premolar extraction for Class III camouflage treatment with completely customized lingual appliances (CCLAs). Treatment outcome was tested against the null hypothesis that lower premolar extractions for non-surgical camouflage treatment of a Class III malocclusion will lead to further compensation by retroclining mandibular incisors during CCLA treatment.MethodsThis retrospective study included 25 patients (f/m 12/13; mean age 20.7 years, SD 9.5 years) with uni- or bilateral Class III molar relationship and a Wits value of ≤ -2 mm. In all consecutively debonded patients, lower premolars were extracted to correct the sagittal relationship with a non-surgical camouflage approach. Lateral head films prior to (T1) and at the end of lingual orthodontic treatment (T2) were used to evaluate skeletal and dentoalveolar effects. A paired t-test with alpha = 5% was used to define differences between the endpoints. The linear correlation between the inclination of the mandibular incisors at T1 and the achieved correction was measured with the Pearson correlation coefficient (PCC). A Schuirmann’s TOST equivalence test was used to check if the final lower incisor inclination was within the defined norms.ResultsThe null hypothesis was rejected as the mean lower incisor inclination was improved by 1.8° despite lower premolar extractions (T1: 86.8°/ T2: 88.6°). There was a strong correlation (-0.75) between the lower incisor inclination at T1 and the achieved correction indicating a controlled correction towards the norm regardless of the initial incisor position. At T2, the interincisal angle as well as the lower incisor inclination were within the norm.ConclusionLower premolar extractions for non-surgical camouflage treatment of a Class III malocclusion will not lead to undesired retroclining of mandibular incisors during CCLA treatment even in severe cases.

The Relationship between Impacted Mandibular Third Molar and Mandibular Canal on Orthopantomogram – A Retrospective Study

Background: Surgical removal of the impacted lower third molar teeth require thorough investigations and assessment, one of these very important investigations is orthopantomogram (OPG) which is the primary assessment method, to determine the relationship between impacted mandibular third molar and mandibular canal. The study aims to determine the relationship between impacted mandibular third molar and mandibular canal on orthopantomogram. Materials and methods: A retrospective of 300 OPGs out of 947 OPG were selected using simple random sampling method. Rood’s criteria was used in assessing the relationship between the apex of the roots and upper border of the inferior alveolar canal. Statistical analysis was performed to assess the relationship between the canal and the impacted lower third molar in relation to the age ,gender and type of impaction.Results: From 300 OPG, 473 impacted teeth were identified, the relation showed, the highest percentage was superimposed with 47.3%, followed by close contact (35.7%), and only 21.7% of the impacted teeth examined has distance between the roots and the upper border of mandibular canal.Conclussion:Mesioangular impaction has higher percentage of superimposition with the mandibular canal with the higher percentage of female58% to male42% ratio.

Adult Herbst-multibracket appliance treatment-how stable are the results very long term?

To investigate the post-treatment (Tx) changes (≥ 15 years) in adult Class II patients treated with Herbst appliance and subsequently a multibracket appliance (MBA). Of 51 potential patients 31 could be located and participated (19 II:1 and 12 II:2). At a mean age of 21.8 ± 7.3 years (T0), Herbst-MBA Tx had been started. The mean post-Tx observation period was 19.8 ± 3.6 years. Study models from before and after Tx (T1, mean age: 23.6 ± 7.4 years), after 3.0 ± 2.8 years of retention (T2, mean age: 26.8 ± 8.3 years) as well as after recall (T3, mean age: 43.4 ± 7.5 years) were evaluated using the PAR index as well as standard occlusal variables. Pre-Tx, the mean values of the 31 participants were: PAR score = 26.1 ± 9.6 points, Class II molar relationship (MR) = 0.7 ± 0.2 cusp widths (CW), overjet = 6.9 ± 2.3mm and overbite = 4.8 ± 2.6mm. After Tx, the mean PAR score was 5.3 ± 2.8. A Class I MR (0.0 ± 0.1 CW) was present while overjet and overbite had decreased to 2.1 ± 0.7 and 1.3 ± 0.8mm, respectively. At recall (19.8 ± 3.6 years post-Tx), a slight PAR score increase (+ 3.1 points) had occurred (final value: 8.4 ± 3.7); this was mainly due to mild increases in overjet, overbite (final values: 3.3 ± 1.4mm and 2.5 ± 1.7mm) and changes in sagittal MR (0.2 ± 0.2 CW). The sample size and the participation rate as well as the unavailability of a comparable control group can be considered as limitations. In addition, no long-term radiographic data could be obtained, and the retention protocol was not uniform. The majority of these issues, however, should be acceptable to due to the duration of the observation period and the uniqueness of the data. In the present sample, Herbst-MBA Tx enabled Class II correction in adults with very good occlusal long-term stability.

Cephalometric Evaluation of the Pre- and Posttreatment Changes after the Correction of Class II Division 1 Malocclusion with Twin Block Appliance in Mixed Dentition.

To evaluate the pretreatment cephalometric records on the dental, skeletal, soft tissue, and incisor relationship with a twin block functional appliance in class II malocclusion patients in and around Mahe; evaluate the posttreatment cephalometric records on the dental, skeletal, soft tissue, and incisor relationship with a twin block functional appliance in class II malocclusion patients in these children; and to compare cephalometrically certain dental, skeletal, and soft tissue points in pretreatment and posttreatment cephalograms in them. This study was conducted on 20 class II patients in the mixed dentition period, who were treated with twin block therapy. Each had to meet the following criteria-(1) skeletal class II malocclusion with retrognathic mandible; (2) full cusp class II molar relationship; and (3) an angle of ANB of 50 or greater at the start of treatment. All patients wore the appliance 24 hours/day. The pretreatment cephalometric head films for the group were taken using standard cephalometric X-ray equipment. The length of time required to achieve a class I molar relationship was assessed. Appointments during the twin block phase were scheduled at intervals of 8 weeks. Lateral head films were obtained again at the posttreatment follow-up stage. There was a significant increase in effective mandibular length, ramus height, SNB, ANB, overjet, overbite, and I to NA (mm and degrees) after twin block therapy. The maxillary incisor position showed a decrease in its value by 4° in five cases. Thus, in the present study, evidence of skeletal and dentoalveolar changes leading to the correction of class II division 1 malocclusion with the twin block functional appliance has been established. However, further studies with a longer period of follow-up and a larger sample are required to substantiate the results of the present investigation. Bimalrag BR, Ephraim R, Ayilliath A, et al. Cephalometric Evaluation of the Pre- and Posttreatment Changes after the Correction of Class II Division 1 Malocclusion with Twin Block Appliance in Mixed Dentition. Int J Clin Pediatr Dent 2024;17(7):783-789.

Psychosocial impact of dental aesthetics in adolescent : an evaluation of a latent profile and its associated risk factors

BackgroundThe psychosocial impact of dental aesthetics (PIDA) has a significant effect on well-being and quality of life. This study aimed to explore the latent heterogeneous classes of the PIDA among adolescents and investigate the relationships among identified subtypes and sociodemographic variables, the status of left-behind children, and the clinical manifestations of malocclusion.MethodsA cross-sectional study on the PIDA among 1451 adolescents aged 11 to 12 years in elementary schools in a rural area in Guangxi, China, was conducted. The PIDA on adolescents was also investigated via latent profile analysis; each predictor was tested via ordinal logistic regression.ResultsThree latent classes for the PIDA were identified: low-risk (48.2%), medium-risk (39.8%), and high-risk (11.9%) groups. There were significant differences among the three latent classes. The results revealed that being female, The duration of maternal employment outside the hometown, the largest anterior maxillary irregularity, the largest anterior mandibular irregularity, and the antero-posterior molar relationship (ORs of 1.737, 1.138, 1.117, 1.157, and OR = 1.242; P < 0.001, < 0.01, < 0.01, < 0.01 and < 0.05, respectively) had significant effects on the PIDA on adolescents.ConclusionsThe occlusal features, being female and the duration of maternal employment outside the hometown are risk factors that influence the PIDA on adolescents. This provides an evidence for improving the PIDA status among rural adolescents.

Impact of maxillary expansion on the sagittal skeletal and dental parameters of growing Class II patients: A systematic review with meta-analysis.

A "spontaneous" correction of the Class II malocclusion has been described after maxillary expansion (ME) treatment. The aim of the present review was to systematically summarize changes in the sagittal dentoskeletal parameters of growing Class II patients after ME. The study protocol was developed according to the PRISMA statement and registered in PROSPERO before literature search, data extraction and analysis. The PICO model was followed in the definition of the research question, search strategies and study selection criteria. Randomized and non-randomized studies on the sagittal effects of ME published in English language without date restrictions were electronically searched across the Cochrane Library, Scopus and MEDLINE/PubMed databases. Changes in sagittal dentoskeletal cephalometric parameters were analysed. The risk of bias in randomized and nonrandomized studies was assessed using the Rob2 and ROBINS-I tools, respectively. A narrative synthesis was performed, focusing on the investigated population, intervention, comparison, and main outcomes. Pairwise meta-analyses were used to compare the outcomes assessed in subjects who underwent ME versus untreated subjects. Ten studies met the inclusion criteria, four were included in the pairwise meta-analyses due to the presence of a control group. Slight but significant improvements in OVJ (MD: -0.36; 95%; CI [-0.69 to -0.01]; p = .04) and 6/6 molar relation (MD: 1.5; 95%; CI [0.69 to 1.61]; p < .0001) were found in patients who underwent ME compared with untreated subjects, whereas no improvement in skeletal parameters was observed. However, the limitations of a small body of moderate-quality evidence and possible confounding factors should be considered. Evidence on the sagittal skeletal and dental effects of ME in Class II patients is still ambiguous, suggesting the need for more clinical trials, including appropriate control subjects, randomization and blinding during outcome assessment.

Class III correction and enhanced periodontal health with aligner treatment in a 53-year-old patient.

In this case report, we describe the successful camouflage treatment of a 53-year-old female with dental and skeletal Class III malocclusion combined with anterior crossbite, gingival recession, and mobility of the lower incisors, using clear aligners. The treatment involved periodontal debridement followed by orthodontic treatment. The mandibular posterior teeth were distalized to correct the anterior crossbite and to establish Class I molar relationships. During treatment, the mandibular incisors were intruded, and the mandibular occlusal plane underwent a clockwise rotation due to slight extrusion of the maxillary buccal segments and distalization of the mandibular posterior teeth. Following treatment, all objectives were achieved, including resolution of the anterior crossbite, significant reduction of gingival recession and tooth mobility, and improved functional occlusion. The dental and skeletal Class III malocclusion was corrected, and the marginal alveolar bone dehiscence was significantly reduced. The results remained stable over a 3-year retention period, with enhanced molar intercuspation and gingival growth progression. This case adds to the evidence supporting the adaptability and effectiveness of clear aligners in treating orthodontic patients with compromised periodontium. The treatment outcomes support that orthodontic treatment using clear aligners, combined with periodontal monitoring, can assist in managing alveolar bone defects, gingival recession, and tooth mobility.

Case Report: Managing Odontoma and Molar-Incisor-Hypomineralization Challenges in Orthodontics: A Case Report

This report presents the successful orthodontic management of a case of odontoma associated with impaction of the mandibular right permanent canine and Molar-incisor-hypomineralization (MIH). Although case studies have reported the management of odontomas and MIH as separate entities, there is a lack of evidence regarding the comprehensive management of patients presenting with a combination of odontoma, dental impaction, and MIH. A 15-year, 7-month-old female patient complained of the appearance of her smile and the delayed eruption of her mandibular right permanent canine. She was diagnosed with Angle’s Class I molar relationship and Class II canine relationship with the maxillary permanent right lateral incisor in a lingual crossbite. Furthermore, she had mandibular right permanent canine impaction, retained mandibular right primary canine, and MIH in the permanent anterior teeth and first molars. The management involved the removal of the odontoma to allow for orthodontic traction of the lower permanent right canine. After that, the esthetic appearance of the teeth was improved through restorative treatment.

Morphologic predictors of mandibular changes induced by Sander's Bite Jumping Appliance.

This study aimed to identify pretreatment cephalometric variables as possible predictors of the mandibular length increase in Class II patients with mandibular retrusion, treated by means of the Bite Jumping Appliance (BJA). Forty-three subjects (22 males and 21 females) with Class II malocclusion, treated with a BJA, were selected on the basis of the following inclusion criteria: full Class II molar relationship, Overjet (OVJ) ≥ 6 mm and a skeletal Class II malocclusion with mandibular retrusion at the start of the treatment (T0); cervical vertebral maturation stage 2 or 3 at time 0 (T0). The following mandibular structural features were measured on lateral cephalograms at time 0 and time 1 (15 months of treatment): the width and height of the mandibular symphysis and its width/height ratio, the width and height of the mandibular ramus and its width/height ratio, the antegonial notch depth and the Condilion-Gonion-Menton (Co-Go-Me) angle. Post-treatment changes were assessed by Pancherz's cephalometric analysis, evaluating the increases in mandibular length. A regression statistical model was used to test the association between morphologic variables and mandibular length changes. At T1, a significant increase in mandibular length (7.1 + 3.4 mm, p < .001) was measured. A significant negative association between the pretreatment Co-Go-Me angle and mandibular length change was found (p < .05). IMPA angle was negatively associated with mandibular length change. All the others morphological feature were not statistically related to mandibular length change. Co-Go-Me angle and IMPA angle at T0 can be used as predictors for mandibular response to the treatment with BJA.

Predictors of Curve of Spee Leveling in Class II Division 1 Malocclusion Treated With Reverse Curve of Spee Archwires: An Observational Study.

Introduction Aligning and leveling is the initial stage of comprehensive fixed orthodontic treatment aimed at minimizing the depth of the curve of Spee (COS). Various techniques exist to decrease the magnitude of the curve. This study investigates the skeletal and dental factors that reduce COS in individuals with minor class II malocclusions receiving nitinol (NiTi) wires with a reverse curve of Spee (RCS). Materials and methods The data for this observational study was collected from a sample of 84 patients who had class II molar relations and were sequentially treated with RCS NiTi wires throughout the initial leveling and aligning phase. All patients with class II molar relationships underwent non-extraction procedures during the leveling phase. The COS was determined using digitalized dental models. Skeletal and dental characteristics that could impact COS were identified and quantified using digital lateral cephalograms and orthopantomograms recorded during the pre-treatment (T1) and post-leveling (T2) stages. After calibrating the radiographs and models, we acquired angular and linear data. The data was categorized based on gender, growth pattern, and initial alignment of the teeth. We analyzed the differences between the groups using an independent t-test and an ANOVA. A paired t-test was used to compare the difference in the dimensional values between (T1) and (T2) points. Following the correlation coefficient tests, the study used stepwise multiple linear regression analysis to assess the predictive value of independent factors on the COS. The results were considered statistically significant at p < 0.05. Results The COS decreased by -1.43 ± 0.68 mm, which is statistically significant (<0.001*). There is no significant difference in COS reduction between the categorical variables. Despite statistically significant differences in the parameters between pre- and post-treatment, the linear correlation between most of the variables and COS reduction ranged from very weak (<0.20) to weak (0.20-0.39). Conclusions The vertical extrusion of lower premolars and molars combined with the intrusion of lower incisors contributed to the reduction of the COS by RCS wires. There is a change in the orientation of the occlusal plane with the flattening of the COS.

Revolutionizing orthodontics: Effective management of Class III skeletal malocclusion using innovative buccal shelf bone screws

The advent of the temporary anchorage devices has revised the envelope of discrepancy in modern orthodontic practice. Orthodontic camouflage is opted in situations where the patient is reluctant to have an invasive orthognathic surgical procedure and the associated risks or where, by the use of temporary anchorage devices, the orthodontic envelope can be expanded, and optimal orthodontic result can be obtained non surgically. In such cases, TAD’s can be used to obtain an acceptable orthodontic result with a cusp to fossa posterior relation, an optimal aesthetic outcome, and a functional occlusion. This case report showcases a camouflage treatment of a Class III non-growing patient treated by use of TAD’s, to cause clockwise rotation of maxillo- mandibular occlusal complex for achieving optimum molar relation, facial esthetics, and function.A case of skeletal and Angle’s Class III malocclusion is presented where orthodontic camouflage was carried out to deliver optimal orthodontic results. This was achieved effectively by in toto distalization of the lower arch. This was brought about with the use of two extra alveolar TAD’s placed in the buccal shelf region of the lower arch. Two 2 x 12 mm bone screws were used, after space creation by extraction of lower third molars bilaterally, and elastic chains was the chosen force delivery system. Here in toto distalization of the lower arch was achieved to end in an Angle’s class I molar and canine relationship with normal overjet and overbite. Total treatment duration was of 17 months.Challenging skeletal malocclusions can be treated non surgically by effective use of TAD’s and correct and efficient use of biomechanics.

Relationships between HDL subpopulation proteome and HDL function in overweight/obese people with and without coronary heart disease

Background and aimsThe structure-function relationships of high-density lipoprotein (HDL) subpopulations are not well understood. Our aim was to examine the interrelationships between HDL particle proteome and HDL functionality in subjects with and without coronary heart disease (CHD). MethodsWe isolated 5 different HDL subpopulations based on charge, size, and apolipoprotein A1 (APOA1) content from the plasma of 33 overweight/obese CHD patients and 33 age-and body mass index (BMI)-matched CHD-free subjects. We measured the relative molar concentration of HDL-associated proteins by liquid chromatography tandem mass spectrometry (LC-MS/MS) and assessed particle functionality. ResultsWe quantified 110 proteins associated with the 5 APOA1-containing HDL subpopulations. The relative molar concentration of these proteins spanned five orders of magnitude. Only 10 proteins were present in >1% while 73 were present in <0.1% concentration. Only 6 of the 10 most abundant proteins were apolipoproteins. Interestingly, the largest (α-1) and the smallest (preβ-1) HDL particles contained the most diverse proteomes. The protein composition of each HDL subpopulation was altered in CHD cases as compared to controls with the most prominent differences in preβ-1 and α-1 particles. APOA2 concentration was positively correlated with preβ-1 particle functionality (ABCA1-CEC/mg APOA1 in preβ-1) (R2 = 0.42, p = 0.005), while APOE concentration was inversely correlated with large-HDL particle functionality (SRBI-CEC/mg APOA1 in α-1+α-2) (R2 = 0.18, p = 0.01). ConclusionsThe protein composition of the different HDL subpopulations was altered differentially in CHD patients. The functionality of the small and large HDL particles correlated with the protein content of APOA2 and APOE, respectively. Our data indicate that distinct particle subspecies and specific particle associated proteins provide new information about the role of HDL in CHD.

ASSOCIATION OF CHEILOSCOPY, DACTYLOSCOPY, AND PALATAL RUGOSCOPY WITH PERMANENT MOLAR RELATIONSHIP IN CHILDREN

Background: To record and study the correlation of the predominance of recorded cheiloscopic, dactyloscopic and palatal rugoscopic patterns with molar relationship in 8-15 years of children in order to determine if there exists any association between them. Material and Methods: 505 children of age group 8-15 years of old with completely erupted 2nd permanent molars upto occlusal table were recruited and angles molar relation was recorded in the proforma. Lip prints of these subjects were recorded with lipstick-cellophane method and middle 10mm of lower lip was analysed for the lip print pattern as suggested by Sivapathasundharam et al. The patterns were classified based on Tsuchihashi and Suzuki classification. The patent prints of finger were recorded in the performa and analysed according to Michael Kucknas method. The palatal rugae was obtained by photographs and alginate impression of the upper arch for each patient and were defined using a sharp graphite pencil under adequate light and magnification and were recorded according to the classification given by Thomas and Kotze classification. Results: In cheiloscopic patterns: Type I pattern was found to be the most predominant cheiloscopic pattern in class I and class III molar relation whereas Type II pattern in class II molar relation. The composite patterns showed the most prominent dactyloscopic patterns in class I and class II molar relation and loop patterns were found as the most prominent in class III molar relation. In case of rugoscopic pattern in class 1 and class 3 molar relation group, the curve pattern showed the most prominent and wavy pattern in class 2 molar relation. No statistical significance was found in all the three parameters. Conclusions:co -relation of the lip, finger and palatal rugae patterns with molar relation might aid in the early diagnosis and interception of malocclusion among paediatric patients as it is easily accessible, economical and non-invasive marker for the aforementioned conditions.Further investigations, may be required on the relationship between cheiloscopic, dactyloscopy and rugoscopic patterns with malocclusion in order to substantiate the findings presented herein.

Chelioscopy and Molar Relationship among Young Adults

Chelioscopy and Molar Relationship among Young Adults

Dietary Pectin from Premna microphylla Turcz Leaves Prevents Obesity by Regulating Gut Microbiota and Lipid Metabolism in Mice Fed High-Fat Diet.

The present study was designed to investigate the protective effects of pectin extracted from Premna microphylla Turcz leaves (PTP) against high-fat-diet (HFD)-induced lipid metabolism disorders and gut microbiota dysbiosis in obese mice. PTP was made using the acid extraction method, and it was found to be an acidic pectin that had relative mole percentages of 32.1%, 29.2%, and 26.2% for galacturonic acid, arabinose, and galactose, respectively. The administration of PTP in C57BL/6J mice inhibited the HFD-induced abnormal weight gain, visceral obesity, and dyslipidemia, and also improved insulin sensitivity, as revealed by the improved insulin tolerance and the decreased glucose levels during an insulin sensitivity test. These effects were linked to increased energy expenditure, as demonstrated by the upregulation of thermogenesis-related protein UCP1 expression in the brown adipose tissue (BAT) of PTP-treated mice. 16S rRNA gene sequencing revealed that PTP dramatically improved the HFD-induced gut dysbiosis by lowering the ratio of Firmicutes to Bacteroidetes and the quantity of potentially harmful bacteria. These findings may provide a theoretical basis for us to understand the functions and usages of PTP in alleviating obesity.

Dentoalveolar bone height in Class I adults with different vertical patterns: A cross-sectional study

Facial divergence during growth and development affects both the anterior and posterior alveolar bone dimensions in the maxilla and mandible, and the dentoalveolar compensation mechanism in severe vertical skeletal discrepancies remains unclear. To evaluate the: (1) difference in dentoalveolar heights among subjects with different vertical facial patterns; (2) association between the dentoalveolar bone height and other cephalometric variables; (3) effect of sex on dentoalveolar height measurements. Non-growing subjects with skeletal Class I (0°<ANB<4°), Class I canine and molar relationship and complete fully erupted dentition were included in the study. Cephalometric measurements were taken on lateral cephalograms and patients were stratified into hyperdivergent, hypodivergent, and normodivergent groups based on MP/SN angle. A two-way analysis of variance (ANOVA) was used to compare cephalometric measurements between the divergence and sex groups. Measurements on a total of 204 patients (81 males, 123 females) were analysed. At the level of the incisor and premolar regions, both dentoalveolar and alveolar bone heights were significantly larger in hyperdivergent group when compared to hypodivergent group, whereas at the level of the molar region, no difference was found among groups. Moderate to strong correlations were found between dentoalveolar bone and vertical skeletal measurements. In the maxilla and mandible, the dentoalveolar compensation mechanism in skeletal Class I subjects results in an increased vertical height in the anterior dentoalveolar segment in hyperdivergent subjects and a reduced one in hypodivergent subjects.

Development of an HPLC method using relative molar sensitivity for the measurement of blood concentrations of nine pharmaceutical compounds

We developed a reliable high-performance liquid chromatographic analysis method using a relative molar sensitivity (RMS) technique that does not require an authentic, identical reference analyte material to quantify blood serum carbamazepine, phenytoin, voriconazole, lamotrigine, meropenem, mycophenolic acid, linezolid, vancomycin, and caffeine levels for routine blood concentration measurements. Carbamazepine and caffeine were also used as non-analyte reference materials to calculate the RMS of each analyte. The RMS was calculated from the ratio of the slope of the calibration equation (analyte/non-analyte reference material), then used to quantify analytes in control serum samples spiked with carbamazepine, phenytoin, voriconazole, meropenem, mycophenolic acid, linezolid or vancomycin. In addition, the concentrations of these six drugs in control serum samples determined by the proposed RMS method agreed well with that obtained using a conventional method. The proposed RMS method is a promising tool for the clinical determination of nine drugs, given the accuracy, precision, and efficiency of quantifying these analytes.

Assessing the Efficacy of Early versus Late Orthodontic Intervention in the Management of Class II Malocclusion: A Comparative Analysis

ABSTRACT Background: Class II malocclusion is a common orthodontic issue characterized by the excessive protrusion of the upper teeth relative to the lower teeth. Early intervention during mixed dentition has been advocated to guide skeletal growth and potentially reduce the severity of malocclusion. Materials and Methods: A comparative analysis was conducted to evaluate the efficacy of early (before the pubertal growth spurt) versus late (after the pubertal growth spurt) orthodontic intervention in managing Class II malocclusion. A cohort of 100 patients diagnosed with Class II malocclusion was divided into two groups: early intervention group (n = 50) and late intervention group (n = 50). Treatment outcomes including changes in overjet, molar relationship, and cephalometric measurements were assessed before and after orthodontic treatment. Results: In the early intervention group, the mean reduction in overjet was 5.2 mm (SD = 1.3), while in the late intervention group, it was 3.8 mm (SD = 1.6). The improvement in molar relationship was greater in the early intervention group (mean change = 4.5 mm, SD = 1.1) compared to the late intervention group (mean change = 3.1 mm, SD = 1.4). Cephalometric analysis revealed significant differences in skeletal and dental parameters between the two groups, with greater improvements observed in the early intervention group. Conclusion: Early orthodontic intervention shows superior efficacy in managing Class II malocclusion compared to late intervention. Early treatment leads to greater reductions in overjet, improvements in molar relationship, and favorable changes in skeletal and dental parameters. These findings underscore the importance of timely orthodontic intervention, particularly during the mixed dentition stage, for optimal management of Class II malocclusion.

Prevalence of Malocclusion and Orthodontic Treatment Need in 9- to 12-Year-Old Schoolchildren in Ulaanbaatar, Mongolia.

Background The prevalence of malocclusion in Mongolia is increasing every year. Estimating the need for orthodontic treatment in the population is crucial for planning orthodontic care services and monitoring oral health programs. Therefore, the present study aimed to assess the need for orthodontic treatment among schoolchildren in Ulaanbaatar, Mongolia, using the Index of Orthodontic Treatment Need (IOTN). Methods A total of 656 schoolchildren aged 9-12 years were enrolled from 8 schools located in urban and suburban areas of 6 districts of Ulaanbaatar city. All the children were assessed according to the two components of the IOTN, the Dental Health Component (DHC) and the aesthetic component (AC). Statistical analyses were carried out using IBM SPSS Statistics for Windows, Version 28 (Released 2021; IBM Corp., Armonk, New York, United States). Results The prevalence of malocclusion was 561 (84.5%), consisting of 452 (68%) Angle Class I, 178 (26.8%) Angle Class II, and 34 (5.2%) Angle Class III malocclusion. For the DHC, the moderate need for treatment was 194 (29.3%) and the definite need was 53 (8.1%). For the AC, the moderate need was 148 (22.3%) and the definite need was 45 (6.9%). The association between the DHC and the AC was found to be statistically significant (p<0.001). The most common malocclusions were an increased overjet (maxillary protrusion), a contact point displacement (crowding), and an increased overbite (deep bite). The AC, Angle's molar relationship, an increased overjet, a contact point displacement, and an increased overbite were factors associated with the need for orthodontic treatment. Conclusion Approximately one-third of schoolchildren in Ulaanbaatar, Mongolia, require orthodontic treatment. This finding helps dental practitioners to better understand oral health problems, leading to an improvement in the overall quality of life of children.