Does cleft lip and palate affect the severity of malocclusion?

OBJECTIVE: The purpose of this study was to evaluate the 3D anatomical features of unilateral (UCLP) and bilateral (BCLP) complete cleft lip and palate with those of skeletal Class III dentofacial deformities. MATERIALS AND METHODS: In total, 92 patients were divided into cleft and noncleft groups. The cleft group comprised 29 patients with UCLP and 17 patients with BCLP. The noncleft group comprised 46 patients with Class III dentofacial deformities. 3D anatomical landmarks were identified and the corresponding measurements were made on the cone-beam computed tomography (CBCT). RESULTS: The differences between the affected and unaffected sides of the patients with UCLP were nonsignificant. The differences between the patients with UCLP and BCLP were nonsignificant except for the SNA angle. Significant differences between the patients with clefts and Class III malocclusion were identified for the SNA, A-N perpendicular, and A-N Pog line, indicating that the maxillae of the patients in the cleft group were more retrognathic and micrognathic. Relative to the noncleft group patients, the cleft group patients had a significantly smaller ramus height. CONCLUSION: The affected and unaffected sides of the patients with UCLP did not exhibit significant differences. The maxillae of the patients with UCLP were significantly more retrognathic than those of the patients with BCLP. The maxillae and mandibles of the patients in the cleft group were more micrognathic and retropositioned relative to those of the noncleft Class III patients. CLINICAL RELEVANCE: The maxillary and mandibular findings indicated greater deficiencies in the patients with UCLP or BCLP than in those with skeletal Class III malocclusion. Appropriate surgical design should be administered.

The Impact of Mandibular Distraction Osteogenesis on Cephalometric Measurements in Infants with Pierre Robin Sequence.

BACKGROUND: The obstruction of the upper airway (UAO) in infants diagnosed with Robin Sequence (RS) is caused by micrognathia, and in severe cases, it can result in obstructive sleep apnea (OSA). Mandibular distraction osteogenesis (MDO) is a secure and efficient remedy for significant UAO. However, there is insufficient data on the related cephalometric changes. Therefore, this study meticulously analyzes the mandibular cephalometric changes in infants with RS who have undergone MDO using internal devices. The aim is to gain a more comprehensive understanding of the short- and long-term impacts of distraction on the mandible. METHODS: The study examined 73 consecutive cases of mandibular distraction osteogenesis (MDO) performed by a single surgeon. Preoperative and postoperative lateral cephalograms, as well as CT scans of the mandible, were utilized to assess population averages for both time points. A two-sample T-Test with equal variance was used for this analysis. RESULTS: After the MDO procedure, 19 out of 21 cephalometric parameters exhibited significant morphological changes. On average, there were notable improvements of 20.3 mm (60.7%) in length, 9.8 mm (49.7%) in height, 12.6 mm (36.1%) in width, and 211% in airway parameters. However, most parameters showed only mild regression at the time of device removal and 6 to 12 months post-MDO. Nonetheless, the cephalometric parameters remained significantly improved compared to the preoperative measurements. CONCLUSIONS: The use of cephalometric measurement is a potent approach that provides a clear and measurable understanding of how MDO influences both immediate and long-term growth of the mandible. This quantitative assessment of the effects of mandibular distraction allows for the refinement of surgical techniques and the optimization of outcomes. Therefore, incorporating cephalometric measurements in the evaluation of patients undergoing MDO can lead to better surgical planning and more favorable results.

Relationship between congenital absence of third molars and craniomaxillofacial structure / 口腔医学

Objective@# To analyze the correlation between third molar agenesis and craniofacial morphology by studying the location and number of congenital missing third molars and results of craniofacial cephalometric measurement. @*Methods@# A total of 123 patients were included, including 64 patients in the control group without congenital third molar absence and 59 patients in the absence group with at least one third molar absent. Cephalometric measurements included FMA, IMPA, AR-Go, GoGn-Sn, Co-A, Co-Gn, ANS-Me, Go-Me, SN-MP, Ar-Go-Me, SNA, SNB, ANB, Y-axis angle, Y-axis length, Ar-Go, Go-Me, MP-OP, FH-PP, FH-OP, a total of 18 bone tissue indicators, U1-SN, U1-L1, U1-NA, L1-NB, U1-APo and L1-APo, a total of 6 dental indicators, and UL-EP, LL-EP and nasolabial angle, a total of 3 soft tissue indicators. The correlation between congenital agenesis of third molars and craniofacial morphology was analyzed. @*Results@# The most common missing location of the third molar occured in the upper jaw and the most common number of missing teeth was one. In control group, Ar-Go-Me and SN-MP were larger (P<0.05), U1-SN, U1-NA, L1-NB, UL-EP and LL-EP were larger (P<0.05), and U1-L1 was smaller (P<0.01). There were no significant differences in Ar-Go and Go-Me between the two groups(P>0.05). @*Conclusion @#Patients with four third molars are more likely to have backward and downward rotation of the mandible and are more likely to develop into a convex facial type than patients with missing third molars, which has a higher correlation with hyperdivergent growth pattern and convex facial type.

The effect of combined maxillary pad movable appliance and FR-III functional appliance in the treatment of skeletal Class III malocclusion of deciduous teeth.

BACKGROUND: To evaluate the therapeutic effect of maxillary pad movable appliance combined with FR-III functional appliance in treating skeletal Class III malocclusion of deciduous teeth and provide a reference for optimizing clinical treatment methods. METHODS: A total of 30 pediatric patients were randomly selected between April 2012 and April 2019. They were in stage IIA osseous skeletal Class III malocclusion, treated with maxillary pad movable appliance to relieve the reverse, combined with FR-III functional appliance to maintain a median relationship to stage IIIA. A self-control study of children before and after treatment was used, and paired t-test was used to evaluate the changes in the measurement indexes of the IIA and IIIA stage X-rays and changes in the bone and soft tissue profiles. RESULTS: After 3 years of treatment, SNA, ANB, and NA-PA in the sagittal osteofacial index of the jawbones increased, SNB decreased, and the Y-axis angle in the vertical index of the jawbones increased. U1-SN, U1-NA, U1-NA distance, L1-MP, L1-NB, and L1-NB distance in the index of labial inclination of upper and lower central incisors increased, while U1-L1 decreased. The sagittal anomalies of the jawbones were improved, and there were significant differences before and after treatment (P < 0.05). FCA, ULP, and UL-EP increased, soft-tissue facial prominence and facial height increased, and the relationship between the upper lip and the aesthetic plane was harmonious. None of the 30 children with skeletal Class III malocclusion in the deciduous stage experienced recurrence in stage IIIA. CONCLUSIONS: Combined treatment with the maxillary pad movable appliance and the FR-III functional appliance is suitable for children with skeletal Class III malocclusion in the deciduous stage.

Evaluating the effect of digital technology on the learning of orthodontic cephalometric measurement.

Background: This study aimed to evaluate the effectiveness of integrating digital technology into cephalometric measurement teaching. Methods: In total, 94 undergraduates of stomatology were recruited and randomly allocated to two groups. According to the cross-over design, both groups completed cephalometric measurements by the traditional hand-drawn method and digital technology (the Dolphin software) in different order. In the traditional hand-drawn method, students depicted the outline of the craniofacial anatomical structures on sulfuric transfer paper first, then marked the measurement points and completed the measurement of line spacings and angles; by digital technology, they marked the points in the software and adjust the automatically generated outlines of the structures to obtain the results. Two professional orthodontists were invited as instructors and their measurements were set as standards. An online questionnaire was also used to investigate students' attitudes toward digital technology being used in the cephalometric teaching process. Results: There were significant differences of students' measurements ( P 1-SNA<0.01, P 1-SNB=0.01 and P 1-L1-NB (mm)<0.01; SNA: sella-nasion-subspinale angle, SNB: sella-nasion-supramental angle, L1-NB (mm): the distance from the lower central incisor tip to the nasion-supramental plane) between the traditional method and digital technology. Besides, the results of most items by digital technology were closer to the standards than those by the traditional method, including five items with statistical significance ( P 2-SNB<0.05, P 2-L1-NB (mm)<0.01, P 2-FMA<0.05, P 2-FMIA<0.05, P 2-IMPA<0.01), while three items were the opposite ( P 2-SNA<0.05, P 2-ANB (mm)<0.01, P 2-NA-PA<0.01). The questionnaire showed more students preferred digital technology (33%) as a better teaching method than the traditional method (2%) and 72% of participants thought they had mastered 50-80% of cephalometric knowledge after the course. Conclusions: This study demonstrated effectiveness and acceptance of the course applying digital technology during the cephalometric teaching process.

Effect of anterior overbite malocclusion on smile esthetics in adult patients.

OBJECTIVE: To investigate whether overbite affects smile esthetics. METHODS: This study involved 106 patients with complete pretreatment records. Lateral cephalometric tracings were used to measure hard tissue variables. Frontal smile and upper occlusal photographs were used to measure nine smile esthetic variables: arc ratio, number of teeth, upper incisor exposure, upper midline, buccal corridor ratio, smile index, archform index, lower teeth exposure, and interlabial gap. The patients were classified into three groups according to their overbites (B1: 0-4 mm, B2: >4 mm, and B3: <0 mm). Analysis of variance was performed to compare 14 cephalometric measurements and the 9 smile esthetic variables. Multiple linear regression analysis was performed to determine the influencing cephalometric factors. RESULTS: Only upper incisor exposure was significantly different among the groups. In the multiple linear regression analysis, upper incisor exposure was positively associated with the distance from the upper incisor to the palatal plane in Group B2. No significant correlations were observed between cephalometric measurements and smile variables in Groups B1 and B3. CONCLUSIONS: Smile variables were not significantly different among patients with various overbite malocclusions with the exception of upper incisor exposure. Overbite malocclusions do not appear to influence smile esthetics in adult patients.

The relation of cephalometric features to internal derangements of the temporomandibular joint: A systematic review and meta-analysis of observational studies.

PURPOSE: To review and summarize the data on the relationship between craniofacial morphology features and internal derangement (ID) of the temporomandibular joint (TMJ). METHOD: A systematic review was designed and registered at PROSPERO, CRD42019132731. The PubMed, Embase and Scopus databases were searched for cephalometric studies comparing craniofacial morphology between female patients with TMJ ID and controls. The Newcastle-Ottawa Scale (NOS) was used for quality assessment. Weighted mean differences for cephalometric measurements were pooled for subsequent meta-analysis. RESULT: From the establishment date to August 2020, 14 of 1038 collected records were selected, which consisted of 772 patients with TMJ ID and 423 controls. These records were eventually pooled for the designed statistical analysis after the NOS quality assessment. Compared with the controls, TMJ ID patients had obviously smaller, retruded and clockwise-rotated mandible, showing significantly decreased S-Na, S-Go, Go-Me, Ar-Pog, Ar-Go, SNB, Na perp Pog, and increased FH-MP, SN-MP, PP-MP, SN to Ar-Go, S-Ar-Go and ANB. CONCLUSION: Certain craniofacial morphology features were found strongly associated with the presence of TMJ ID, especially the size and position of the mandible.

Effects of rapid palatal expansion (RPE) and twin block mandibular advancement device (MAD) on pharyngeal structures in Class II pediatric patients from Cluj-Napoca, Romania.

Objective: To compare cephalometric changes of pharyngeal structures after rapid palatal expansion (RPE) with those induced by a twin block mandibular advancement device (MAD) with palatal expansion capability. Methods: This retrospective study investigated 55 Class II pediatric patients, divided into two groups: 29 patients treated with RPE and 26 patients treated with MAD. Lateral cephalometric measurements were compared before and after treatment. Results: Changes in pharyngeal airway space were statistically significant in both groups (p < 0.001) from a pre-treatment mean distance measured between the lower posterior pharyngeal wall and the hyoid bone (LPF-H) of 25.42 mm in the MAD group and 28.62 mm in the RPE group, to a post-treatment mean LPF-H of 27.96 mm in the MAD group and 31.52 mm in the RPE group. Conclusion: Significant changes in pharyngeal space may be obtained in Class II patients through both rapid palatal expansion and mandibular advancement devices with palatal expansion capability.

Distortion and magnification of four digital cephalometric units.

OBJECTIVES: To assess the validity of using the calibration ruler for correcting magnification of linear measurements and to explore and compare the vertical and horizontal magnification of four digital cephalometric units. METHODS: An acrylic box was imaged at seven sagittal positions using four digital cephalometric units: Orthopantomograph OC100, Orthopantomograph OC200, Sirona Orthophos CD, and Sirona Orthophos DS. The true linear lengths of the phantom, corrected, and uncorrected linear lengths on the images were measured and compared. The validity of measurements using the calibration ruler was assessed. The magnification values and distortion indices were calculated and compared among the four cephalometric units. RESULTS: For linear measurements on the mid-sagittal plane and averaged linear measurements on bilateral symmetric sagittal planes, the bias 1.96 STD of the calibration ruler ranged from 1% to 2% for the four cephalometric testing units. For linear measurements on the single lateral sagittal plane, the bias 1.96 STD ranged from 3% to 6%. The vertical scanning charge-coupled device cephalometric unit produced the greatest distortion, ranging from 1.029 to 0.964. CONCLUSION: The metal millimeter calibration ruler is an accurate reference for linear measurement magnification correction. Because of unpredictability and machine specificity, the magnification and distortion of a cephalometric unit should be calibrated for the estimation of cephalometric measurement error.

LATERAL CEPHALOMETRIC MEASUREMENT STANDARDS OF MONGOLIAN CHILDREN WITH NORMAL OCCLUSION FROM 6-15 YEARS OF AGE / Шинэ санаа Шинэ нээлт

@#BACKGROUND. The aim of this study was to analyze craniofacial sagittal and vertical dimensions in subjects with normal occlusions to establish age and gender-specific lateral cephalometric measurement standards for Mongolian children. MATERIAL AND METHODS. The study group consisted of a sample of 642 untreated subjects with normal occlusions from 6 to 15 year old. Craniofacial anatomic landmarks were identified directly on the digital images. A customized cephalometric analysis was used to measure 18 variables of linear measurement and 18 variables of angular measurement on software program (Winceph 11.0). Student’s t-test was employed to test for gender differences in each age. RESULTS. Most of the linear measurements, larger craniofacial distances were recorded in males than females. Also linear measurements were increasing according to age. There were no statistically significant gender differences with regard to most angular measurements at subsequent age groups. Soft tissue analysis revealed flatter profiles in females than in males from the age of 10-11 years onward, while age-dependent changes in the soft tissue profile were similar in both genders. СONCLUSION. In untreated subjects with normal occlusion craniofacial development of the hard can be considered age- and gender-dependent. Therefore age- and gender-specific differences of linear craniofacial distances should be taken into account for diagnosis and treatment planning in children and adolescents. The present results can be used as reference values for children and adolescents of Mongolian origin.

Effects of early treatment of class Ⅲ malocclusion with magnetic orthodontic appliance / 中华医学美学美容杂志

Objective To develop a Class Ⅲ twin-block magnetic orthopedic appliance (TMOA-Ⅲ) and to investigate the treatment effects of this appliance on skeletal Class Ⅲ malocclusion of mixed dentition and early permanent dentition.Methods The sample consisted of 76 Chinese children (42 males and 34 females,mean age 9.1 years) with Class Ⅲ malocclusion caused by maxillary retrognathism,and the subjects were divided into a treatment group and a control group.The treatment group,38 subjects (21 males and 17 females),were instructed to wear TMOA-Ⅲ for 5-8 months (mean 7.5 months) and the control group,38 subjects (21 males and 17 females),did not wear any appliance.Cephalometric radiographs were taken and measurement data were used for analysis.Results Compared with the control group,patients of the treatment group showed a favorable increase of maxilla length and anterior movement (PNS-A,P＜0.001;SNA,A-NPg,P＜0.05),and skeletal Class Ⅲ facial profiles improved (UL-EL,NsPgs-HL,Facial convexity,P ＜ 0.001;LL-EL P ＜ 0.005).Conclusions The results indicate that TMOA-Ⅲ is effective for the treatment of Class Ⅲ malocclusion caused by maxillary retrognathism in mixed dentition and early permanent dentition,which provides another choice for the treatment besides the face mask.

The effects of activator treatment on the hard and soft tissue profile of different skeletal patterns / 实用口腔医学杂志

Objective:To evaluate skeletal,dentoalveolar and soft tissue profile changes by activator therapy in patients with different skeletal patterns of Class Ⅱ1 malocclusions.Methods:22 subjects(10 girls,12 boys,mean age 11.5 ±0.67 years) in the mixed or early permanent dentition,were included and divided into low angle(n =15) and average angle(n =7) groups on the basis of skeletal pattern.All patients were treated with a traditional activator.The skeletal,dentoalveolar and soft tissue profile changes were compared on lateral cephalograms before and after treatment.Statistical analysis was performed with t-test of SPSS 13.0 at a level of significance of P ＜ 0.05.Results:Activator treatment in these growing patients resulted in a correction of the skeletal Class Ⅱ relationship (decrease of ANB,Wits and NA-Pg),an advancement of the mandibular structures(increase of Co-Pg and L1-APg),and changes of the teeth(increase of L6-MP).The changes of Wits,NA-Pg and L1-APg value of low and average angle groups were 1.34° ± 1.82 ° and 3.50 ° ± 1.77°,(3.06 ± 2.00) mm and (5.80 ± 3.17) mm,(-1.16-± 1.74) mm and (-2.83 ± 1.48) mm respectively(P ＜0.05).No statistical significance was found in the soft tissue profile changes whether intra-class or inter-group comparison.Conclusion:The activator appliance is effective in treating growing patients with mandibular deficiency,and mandibular reconstruction,in patients with average angle it is more effective than in those with low angle.

Analysis of measurement accuracy for craniovertebral junction pathology : most reliable method for cephalometric analysis.

OBJECTIVE: This study was designed to determine the most reliable cephalometric measurement technique in the normal population and patients with basilar invagination (BI). METHODS: Twenty-two lateral radiographs of BI patients and 25 lateral cervical radiographs of the age, sex-matched normal population were selected and measured on two separate occasions by three spine surgeons using six different measurements. Statistical analysis including intraclass correlation coefficient (ICC) was carried out using the SPSS software (V. 12.0). RESULTS: Redlund-Johnell and Modified (M)-Ranawat had a highest ICC score in both the normal and BI groups in the inter-observer study. The M-Ranawat method (0.83) had a highest ICC score in the normal group, and the Redlund-Johenll method (0.80) had a highest ICC score in the BI group in the intra-observer test. The McGregor line had a lowest ICC score and a poor ICC grade in both groups in the intra-observer study. Generally, the measurement method using the odontoid process did not produce consistent results due to inter and intra-observer differences in determining the position of the odontoid tip. Opisthion and caudal point of the occipital midline curve are somewhat ambiguous landmarks, which induce variable ICC scores. CONCLUSION: On the contrary to other studies, Ranawat method had a lower ICC score in the inter-observer study. C2 end-plate and C1 arch can be the most reliable anatomical landmarks.

Analysis of Measurement Accuracy for Craniovertebral Junction Pathology : Most Reliable Method for Cephalometric Analysis

OBJECTIVE: This study was designed to determine the most reliable cephalometric measurement technique in the normal population and patients with basilar invagination (BI). METHODS: Twenty-two lateral radiographs of BI patients and 25 lateral cervical radiographs of the age, sex-matched normal population were selected and measured on two separate occasions by three spine surgeons using six different measurements. Statistical analysis including intraclass correlation coefficient (ICC) was carried out using the SPSS software (V. 12.0). RESULTS: Redlund-Johnell and Modified (M)-Ranawat had a highest ICC score in both the normal and BI groups in the inter-observer study. The M-Ranawat method (0.83) had a highest ICC score in the normal group, and the Redlund-Johenll method (0.80) had a highest ICC score in the BI group in the intra-observer test. The McGregor line had a lowest ICC score and a poor ICC grade in both groups in the intra-observer study. Generally, the measurement method using the odontoid process did not produce consistent results due to inter and intra-observer differences in determining the position of the odontoid tip. Opisthion and caudal point of the occipital midline curve are somewhat ambiguous landmarks, which induce variable ICC scores. CONCLUSION: On the contrary to other studies, Ranawat method had a lower ICC score in the inter-observer study. C2 end-plate and C1 arch can be the most reliable anatomical landmarks.

Cranial Cephalometric Measurement using Newly Devised Caliper and Computer Program

The measurement and visualization of the roundness of the cranial circumference has not been attempted by the simple measurement device. That's why there has been a tendency that the morphologic cranial deformity can be diagnosed with accuracy only by the experienced physician. The accurate understanding of the roundness of the cranial circumference, however, is essential for the diagnosis and the decision of the treatment principle in cranofacial morphological deformity. Current methods, such as simple physical examination and/or the photography, are not enough to accurately express the roundness of the cranial circumference. In order to develop the new method of measurement, authors selected 16 points from the axial cutting plane of the cranium. These points can be selected under the same principle even though the axial plane changes. After measuring the distance of 16 points, the values are put into computer program. In conclusion, authors can retrieve the x, y coordinates of the 16 points and can show the intuitive roundness of the circumference of the selected axial plane of the cranium. This measurement tool will be helpful not only for the identification of the severity of the morphologic cranial deformity, but for the classification and the assessment of the result of the surgery.