Tratamiento temprano de la mordida cruzada anterior: informe de un caso clínico / Early treatment of the anterior crossbite. a clinical case report

Objetivo: presentar un caso clínico de mordida cruzada anterior funcional tratado mediante la técnica de Pistas Directas Planas. Caso clínico: Niña de cuatro años de edad, con diagnósticode mordida cruzada anterior funcional en dentición decidua. Su tratamiento se realizó en el Servicio Integral I del Hospital de Odontología Infantil “Don Benito Quinquela Martín”. La corrección de la maloclusión se logró tras 2 meses de uso de las Pistas Directas Planas. Estas fueron removidas a los 6 meses, cuando se observó una correcta posiciónmandibular, intercuspidación posterior y una función oclusal estable, que devolvieron el equilibrio al sistema estomatognático. Conclusión: Las Pistas Directas Planas constituyen unaalternativa de tratamiento temprano para las maloclusiones. Su sencillez en la realización, su eficacia en los resultados y el bajo costo económico hace que sea un método de elección.

Aim: to illustrate a clinical case of functional anteriorcrossbite treated using Planas Direct Tracks.Case report: A four-year-old female patient withfunctional anterior crossbite in deciduous dentition wastreated at the “Don Benito Quinquela Martín” Children’sDental Hospital. The correction of the malocclusion wasachieved 2 months after using planas direct tracks. Thedevice was removed 6 months later getting a mandibularcorrect position and intercuspidation, returning the balanceto the stomatognathic system through a balancedocclusal function.Conclusion: The use of Planas Direct Tracks is an earlytreatment alternative for malocclusions. Its simplicity ofimplementation, efficiency in results and low cost makes it asuitable method.

Classification and characterization of class III malocclusion in Chinese individuals.

BACKGROUND: Class III malocclusion is a maxillofacial disorder that is characterised by a concave profile and can be attributed to both genetic inheritance and environmental factors. It is a clinical challenge due to our limited understanding of its aetiology. Revealing its prototypical diversity will contribute to our sequential exploration of the underlying aetiological information. The objective of this study was to characterize phenotypic variations of Class III malocclusion via a lateral cephalometric analysis in a community of Chinese individuals. METHOD: One-hundred-and-forty-four individuals (58 males ≥18 and 86 females ≥16) with Class III malocclusion ranging from mild to severe were enrolled in this study. Principal component analysis and cluster analysis were performed using 61 lateral cephalometric measurements. RESULTS: Six principal components were discovered in the examined population and were responsible for 73.7 % of the variability. Four subtypes were revealed by cluster analysis. Subtype 1 included subjects with mild mandibular prognathism with a steep mandibular plane. Subjects in subtype 2 showed a combination of prognathic mandibular and retrusive maxillary with a flat or normal mandibular plane. Subtype 3 included individuals with purely severe mandibular prognathism and a normal mandibular plane. Individuals in subtype 4 had a mild maxillary deficiency and severe mandibular prognathism with the lowest mandibular plane angle. CONCLUSION: The six principal components extracted among the 61 variables improve our knowledge of lateral cephalometric analysis for diagnoses. We successfully identified four Class III malocclusion subtypes, indicating that cluster analysis could supplement the classification of Class III malocclusion among a Chinese population and may assist in our on-going genetic study.

[The classification of malocclusions with facial prognathism and its clinical implications].

Severe skeletal malocclusions with facial prognathism keep high prevalence in Chinese population. The classification and diagnosis of these malocclusions remain challenging due to the complicity and variety in their clinical manifestations, cephalometric morphologies and perceived etiologies. Based on elaborated studies about the extensive clinical archives and records, this article introduced an innovative classification of this specific anomaly, which not only provides with diagnostic specifics, but also indicates the possible etiologies and therapeutic guidance.

A new classification of mandibular asymmetry and evaluation of surgical-orthodontic treatment outcomes in Class III malocclusion.

INTRODUCTION: Facial asymmetry is a common manifestation in patients with Class III malocclusion. The aims of this study were to classify mandibular asymmetry in Class III patients and to evaluate treatment outcomes according to different characteristics of asymmetry. MATERIALS AND METHODS: Three dimensional cone-beam CT images of 38 patients were analyzed for menton deviation and discrepancies between bilateral structures of mandibular ramus and body. The patients were classified into 3 groups. Groups 1 and 2 exhibited a larger distance of ramus to midsagittal plane on menton-deviated side. In group 1, menton deviation was greater than ramus asymmetry and the condition was reversed for group 2. Group 3 had menton deviation contralateral to the side with larger transverse ramus distance. The features of asymmetry were delineated and the outcomes after surgical-orthodontic treatment were analyzed. RESULTS: Group 1 exhibited a roll rotation of mandibular structures. Mandibular deviation of group 2 patients was more of a horizontal shift nature rather than rotation. Group 3 patients displayed a yaw rotation of mandible to the side with lesser growth in body and ramus. After treatment, menton deviation and body asymmetry were significantly improved in all 3 groups, but the effect of therapy on ramus asymmetry was less predictable, especially for group 3. CONCLUSIONS: The classification system is simple and clinically useful and could form a base for future studies on facial asymmetry.

A Comparison of Three Orthodontic Treatment Indices with Regard to Angle Classification.

OBJECTIVES: To calculate the agreement between the Dental Aesthetic Index (DAI) and the Index of Complexity, Outcome and Need (ICON) in assessing orthodontic treatment need and to determine correlations between the Peer Assessment Rating (PAR) and DAI and ICON scores according to Angle classification among patients referred for orthodontic evaluation. STUDY DESIGN: This study included 457 randomly selected patients between 9 to 17 years of age. Patients were divided into four groups according to Angle classification [Class I (n=154), Class II division 1(Class II/1) (n=155), Class II division 2(Class II/2) (n=52) and Class III (n=96)]. Relationships between PAR scores and ICON and DAI scores were evaluated with the Spearman correlation test. Unweighted kappa statistics were used to analyse agreement between the ICON and DAI on the need for treatment, according to Angle classification. RESULTS: Class I malocclusions scored significantly lower than other Angle classifications in all indices. Both the ICON and DAI showed significant positive correlations with the PAR in the general study population. For Class II/2 patients, no correlation was found between PAR and DAI scores. There was significant agreement between the ICON and DAI on treatment need among Class I, Class II/1 and Class II/2 patients however, no agreement was found for Class III malocclusions. CONCLUSIONS: The ICON, DAI and PAR produce similar results and can be used interchangeably for the general orthodontic patient population. However, based on Angle classification, prominent differences exist in scoring certain occlusal features.

Evolution of Class III treatment in orthodontics.

Angle, Tweed, and Moyers classified Class III malocclusions into 3 types: pseudo, dentoalveolar, and skeletal. Clinicians have been trying to identify the best timing to intercept a Class III malocclusion that develops as early as the deciduous dentition. With microimplants as skeletal anchorage, orthopedic growth modification became more effective, and it also increased the scope of camouflage orthodontic treatment for patients who were not eligible for orthognathic surgery. However, orthodontic treatment combined with orthognathic surgery remains the only option for patients with a severe skeletal Class III malocclusion or a craniofacial anomaly. Distraction osteogenesis can now be performed intraorally at an earlier age. The surgery-first approach can minimize the length of time that the malocclusion needs to worsen before orthognathic surgery. Finally, the use of computed tomography scans for 3-dimensional diagnosis and treatment planning together with advances in imaging technology can improve the accuracy of surgical movements and the esthetic outcomes for these patients.

An interview with Sylvia Frazier-Bowers.

Dr. Frazier-Bowers is an associate professor at the University of North Carolina, Chapel Hill (UNC-CH), in the Department of Orthodontics. She received a BA from the University of Illinois, Urbana-Champaign, and a DDS from the University of Illinois, Chicago. After completing the NIH Dentist-Scientist Program at UNC-CH in Orthodontics (Certificate, 97') and Genetics and Molecular Biology (PhD, 99'), she completed a post-doctoral fellowship at the University of Texas Health Science Center, Houston (UTHSC), in the Department of Orthodontics. Leadership positions include president of local NC-AADR (North Carolina (2005-2006); director of the AADR Craniofacial Biology group (CBG) 2004-2007; IADR/AADR councilor for NC-AADR (2007, 2008, 2012) and for the CBG (2012-2015); member of Southern Association of Orthodontists Scientific Affairs Committee (2005-2013) and the American Association of Orthodontists Council on Scientific Affairs (2014 ­ Present). Dr. Frazier-Bowers also serves various editorial boards including the Journal of Dental Research and the Scientific Advisory board for the Consortium on Orthodontic Advances in Science and Technology. Her current role as faculty at UNC-CH includes conducting human genetic studies to determine the etiology of inherited tooth disorders, mentoring students at all levels, teaching graduate and pre-doctoral level Growth and Development courses and treating patients in the UNC School of Dentistry faculty practice in Orthodontics.

[Dentoalveolar compensation in skeletal Class III patients treated with orthognathic surgery].

OBJECTIVE: To investigate the compensation of the upper and lower incisors in skeletal Class III patients treated with orthodontic-surgical approach. METHODS: The samples consisted of 54 skeletal Class III patients treated with orthodontic-surgical approach from November 2011 to January 2015. Lateral cephalograms were taken before treatment. The differences between the samples and the norms from Peking University normal occlusion sample library were assessed using independent-sample t test. Correlation analyses were performed to find associations between skeletal and dental parameters. According to skeletal anteroposterior discrepancy/vertical type (ANB/SN-MP), the samples were allocated into group A (ANB < -4°, SN-MP ≤ 37.7°, n = 11), group B (ANB ≥ -4°, SN-MP ≤ 37.7°, n = 16), group C (ANB < -4°, SN-MP > 37.7°, n = 14), and group D (ANB ≥ -4°, SN-MP > 37.7°, n = 13). After measurement of variables, one-way ANOVA with SNK multiple comparison test were performed. RESULTS: The maxillary incisors were more proclined and the mandibular incisors more retroclined in skeletal Class III patients compared with norm values (P < 0.01). Both skeletal anteroposterior discrepancy and vertical type were correlated with the position of upper and lower incisors (P < 0.01). According to skeletal anteroposterior discrepancy/vertical type, no significant differences were found in the upper incisors' inclination among the four groups, while patients in group A and group D exhibited significant difference in lower incisor compensation. CONCLUSIONS: Different skeletal anteroposterior discrepancy/vertical type resulted in varied incisors' compensation. Therefore, decompensation should be treated differently.

FIXED OR REMOVABLE APPLIANCE FOR EARLY ORTHODONTIC TREATMENT OF FUNCTIONAL ANTERIOR CROSSBITE.

Anterior crossbite with functional shift also called pseudo Class III is a malocclusion in which the incisal edges of one or more maxillary incisors occlude with the incisal edges of the mandibular incisors in centric relationship: the mandible and mandibular incisors are then guided anteriorly in central occlusion resulting in an anterior crossbite. Early correction, at the mixed dentition stage, is recommended, in order to avoid a compromising dentofacial condition which could result in the development of a true Class III malocclusion and temporomandibular symptoms. Various treatment options are available. The method of choice for orthodontic correction of this condition should not only be clinically effective, with long-term stability, but also cost-effective and have high patient acceptance, i.e. minimal perceived pain and discomfort. At the mixed dentition stage, the condition may be treated by fixed (FA) or removable appliance (RA). To date there is insufficient evidence to determine the preferred method. The overall aim of this thesis was therefore to compare and evaluate the use of FA and RA for correcting anterior crossbite with functional shift in the mixed dentition, with special reference to clinical effectiveness, stability, cost-effectiveness and patient perceptions. Evidence-based, randomized controlled trial (RCT) methodology was used, in order to generate a high level of evidence. The thesis is based on the following studies: The material comprised 64 patients, consecutively recruited from the Department of Orthodontics, Faculty of Odontology, Malmö University, Sweden and from one Public Dental Health Service Clinic in Malmö, Skane County Council, Sweden. The patients were no syndrome and no cleft patients. The following inclusion criteria were applied: early to late mixed dentition, anterior crossbite affecting one or more incisors with functional shift, moderate space deficiency in the maxilla, no inherent skeletal Class III discrepancy, ANB angle > 0 degrees, and no previous orthodontic treatment. Sixty-two patients agreed to participate and were randomly allocated for treatment either with FA with brackets and wires, or RA, comprising acrylic plates with protruding springs. Paper I compared and evaluated the efficiency of the two different treatment strategies to correct the anterior crossbite with anterior shift in mixed dentition. Paper II compared and evaluated the stability of the results of the two treatment methods two years after the appliances were removed. In Paper III, the cost-effectiveness of the two treatment methods was compared and evaluated by cost-minimization analysis. Paper IV evaluated and compared the patient's perceptions of the two treatment methods, in terms of perceived pain, discomfort and impairment of jaw function. The following conclusions were drawn from the results: Paper I. Anterior crossbite with functional shift in the mixed dentition can be successfully corrected by either fixed or removable appliance therapy in a short-term perspective. Treatment time for correction of anterior crossbite with functional shift was significantly shorter for FA compared to RA but the difference had minor clinical relevance. Paper II. In the mixed dentition, anterior crossbite affecting one or more incisors can be successfully corrected by either fixed or removable appliances, with similarly stable outcomes and equally favourable prognoses. Either type of appliance can be recommended. Paper III. Correction of anterior crossbite with functional shift using fixed appliance offers significant economic benefits over removable appliances, including lower direct costs for materials and lower indirect costs. Even when only successful outcomes are considered, treatment with removable appliance is more expensive. Paper IV. The general levels of pain intensity and discomfort were low to moderate in both groups. The level of pain and discomfort intensity was higher for the first three days in the fixed appliance group, and peaked on day two for both appliances. Adverse effects on school and leisure activities as well as speech difficulties were more pronounced in the removable than in the fixed appliance group, whereas in the fixed appliance group, patients reported more difficulty eating different kinds of hard food. Thus, while there were some statistically significant differences between patients' perceptions of fixed and removable appliances but these differences were only minor and seems to have minor clinical relevance. As fixed and removable appliances were generally well accepted by the patients, both methods of treatment can be recommended.

Permanent mandibular canine(s) impaction: expansion of our understanding.

INTRODUCTION: Eruption disturbances, tooth size and specific malocclusions are known to be genetically influenced. The clinical association between these traits may indicate common genetic controls. OBJECTIVES: A cross-sectional clinical study was designed to test the null hypothesis that the maximum mesiodistal crown diameter (MMD) of maxillary and mandibular central and lateral incisors and the prevalence of various classes of incisor relationships (Class I, II/1, II/2 and III) do not differ between the subjects with and without permanent mandibular canine(s) impaction. METHODS: Dental models of 43 subjects diagnosed with mandibular canine(s) impaction (Impaction Group - IG) were compared with those of 86 subjects of a control reference sample (Control Group - CG). Independent t-test and chi-square tests were used to determine the association between mandibular canine(s) impaction and the MMD of the incisors and the incisor relationship, respectively. The likelihood of various incisor relationships between the IG and CG were evaluated according to odds ratios. RESULTS: A fourfold increase (p < 0.0001) in the overall frequency of Class II/2 incisor relationship was observed in the IG when compared to controls. CONCLUSIONS: The null hypothesis was rejected. Subjects with mandibular canine(s) impaction appeared to be characterised with wider incisors and a remarkably high rate of Class II/2 malocclusion. This information assists the understanding of genetically controlled dental anomalies, which are likely to coexist with mandibular canine(s) impaction.

Magnetic resonance imaging-verified temporomandibular joint disk displacement in relation to sagittal and vertical jaw deformities.

This retrospective study was designed to analyze the relationships between temporomandibular joint (TMJ) disk displacement and skeletal deformities in orthodontic patients. Subjects consisted of 460 adult patients. Before treatment, lateral cephalograms and TMJ magnetic resonance imaging (MRI) were recorded. Subjects were divided into six groups based on TMJ MRI according to increasing severity of TMJ disk displacement, in the following order: bilateral normal TMJs, unilateral disk displacement with reduction (DDR) and contralateral normal, bilateral DDR, unilateral disk displacement without reduction (DDNR) and contralateral normal, unilateral DDR and contralateral DDNR, and bilateral DDNR. Subjects were subdivided sagittally into skeletal Class I, II, and III deformities based on the ANB (point A, nasion, point B) angle and subdivided vertically into hypodivergent, normodivergent, and hyperdivergent deformities based on the facial height ratio. Linear trends between severity of TMJ disk displacement and sagittal or vertical deformities were analyzed by Cochran-Mantel-Haenszel test. The severity of TMJ disk displacement increased as the sagittal skeletal classification changed from skeletal Class III to skeletal Class II and the vertical skeletal classification changed from hypodivergent to hyperdivergent. There were no significant differences in the linear trend of TMJ disk displacement severity between the sexes according to the skeletal deformities. This study suggests that subjects with skeletal Class II and/or hyperdivergent deformities have a high possibility of severe TMJ disk displacement, regardless of sex.

New model for surgical and nonsurgical therapy in adults with Class III malocclusion.

INTRODUCTION: Not all adult Class III malocclusion patients are candidates for surgical correction. In patient assessment and selection, major issues remain regarding diagnosis and treatment planning. The purpose of this investigation was to ascertain whether adding a transverse parameter to a discriminant analysis could improve the classification of adults with Class III malocclusion into 2 groups of patients: those who can effectively be treated by orthodontic therapy and those who require orthognathic surgery. METHODS: Cephalograms, plaster casts, and extraoral photos of 69 adults with Class III malocclusion were analyzed. A discriminant analysis was performed to identify the variables that best separate the 2 groups. RESULTS: Stepwise variable selection resulted in a new, highly significant (P <0.0001) model of 4 variables that provided the best discriminant function to distinguish between patients with and without indications for surgical correction. The resulting equation was the following: score = -10.988 + 0.243 * Wits + 0.055 * M/M ratio + 0.068 * NSAr - 0.589 * mand MLD. The percentage of patients correctly classified by this equation was 91.3%. The sensitivity was 0.92, and the specificity was 0.89. CONCLUSIONS: In the discriminant analysis, the mandibular midline deviation as a transverse component was included. The addition of the transverse variable led to an improved model concerning the predictive value in Class III malocclusion patients with surgical requirements.

Different skeletal types underlying Class III malocclusion in a random population.

INTRODUCTION: We aimed to investigate the skeletal morphology underlying Class III malocclusion in a random population of young white men. METHODS: We randomly selected 3358 Swiss Army recruits and examined them clinically. Of 77 (2.3%) with Class III malocclusion, 57 agreed to have lateral cephalograms. Mandibular and maxillary relationships (ANB, Wits), positions (SNB, SNA), and relative sizes (GoPg and ANS-PNS related to SN) were determined. Comparison with normal values showed discrepancies. RESULTS: In 75.4% of the subjects, the Class III malocclusion had a skeletal origin. The discrepancy was mainly (47.4%) due to mandibular prognathism or growth excess (10.5% prognathism, 15.8% macrognathia, or 21.1% both), whereas the maxilla alone accounted for 19.3% (10.5% retrognathism, 8.8% micrognathia), and there was a combination of mandibular and maxillary disharmony in 8.7%. Dental compensation was common, with proclined maxillary incisors in 42.1% and retroclined mandibular incisors in 26.3%. CONCLUSIONS: About 75% of the Class III malocclusion had skeletal origin in our subjects, mainly due to mandibular prognathism or macrognathia. The different skeletal types proposed in our study can give guidance in treatment planning and the evaluation of treatment effects in Class III malocclusion and in genetic studies.

Treatment classification of Class III malocclusion.

PURPOSE: The purpose of this study was to identify Class III malocclusions within a pediatric practice that lend themselves to a more favorable treatment outcome at an earlier age (before 10 years) rather than initiating treatment at later adolescent growth stages and also to identify the degree of difficulty of the treatment of the Class III malocclusion. METHODS: Review of the current dental literature pertaining to the different clinical types of Class III malocclusions and their respective treatment protocols was performed. Various classification systems were studied and compared. A new treatment classification system of Class III malocclusions utilizing three dentoalveolar and three skeletal components combined with cephalometric information derived from commonly used cephalometric analyses was developed. RESULTS: Class III treatment types were conclusively identified: 1.) Early orthodontics only, 2.) Early combined orthodontics and orthopedics, 3.) Combined orthodontics and orthognathic surgery. CONCLUSIONS: The conclusion supports Edward H. Angle's finding: "In studying a case of malocclusion, give no thought to the methods of treatment or appliances until the case shall have been classified and all peculiarities and variations from the normal type, occlusion and facial lines have been thoroughly comprehended. Then the requirements and proper plan of treatment becomes apparent".

Morphometric analysis of facial profile in adults.

AIM: Are centroid size, principal component analysis (PCA) and thin-plate splines (TPS) sufficient for determining facial morphology? Is it possible to identify relationships between cranial morphology, gender and facial profile? MATERIAL AND METHODS: Profile photos of 110 adult patients were measured according to A.M. Schwarz landmarks using Onyx Ceph. Centroid size was calculated from x and y-coordinates. After Procrustes transformation, a principal component analysis for identifying major components of facial morphology was performed and the results visualized using thin-plate splines. At the same time, lateral cephalograms of all patients were analyzed according to Hasund. RESULTS: There were significant differences in centroid size betweeen male and female patients. Only the vertical skeletal structure had an impact on centroid size. Six components (PC1 to PC6) were identified using PCA. They were responsible for 86.5% of the variance. PC1 (33.9%) described scaling along an axis from Porion to chin. PC2 (28.6%) characterized the vertical dimensions of the lower face. Significant differences were only apparent between males and females in PC3 and PC4. In terms of cephalometric parameters, PC2 and PC3 differed in the vertical, and PC1 und PC2 in the sagittal configuration. CONCLUSIONS: The analyses presented here suffice for describing facial morphology qualitatively and quantitatively as demonstrated by this example. Separating size from shape is useful for investigating therapeutically and growth-related morphological changes. It is difficult to draw conclusions about skeletal parameters.

Progenie / Class III malocclusion

Se realiza una revisión de las distintas clases de progenies de acuerdo a su etiología y desarrollo. Se incluye una descripción de los posibles tratamientos según los casos. Las maloclusiones Clase III se caracterizan por una posición mesial de la arcada dentaria mandibular respecto a la maxilar, produciendo una mordida cruzada anterior. Con grecuencia estos pacientes presentan una maloclusión dentoesquelética, resultado de una deficiencia maxilar, prognatismo mandibular o una combinación de ambos. Su etiologá es poligénica, donde interactúa la genética y los factores ambientales. Esta maloclusión comrpomete mucho la estética facial, lo que hace que se busque frecuentemente atención temprana

Phenotypic characterization of Class III patients.

OBJECTIVE: The objective of this study is to characterize the convergences of dentofacial form of skeletal Class III malocclusion in individuals to test the fundamental hypothesis that there are distinct subtypes of Class III malocclusion. MATERIALS AND METHODS: A detailed phenotypic characterization was performed on a retrospective cohort of 309 subjects using cluster and principal component analyses on 67 cephalometric variables. RESULTS: The results indicated that there are five clusters representing distinct subphenotypes. The principal component analysis suggested that the groupings of variables reflect anteroposterior and vertical dimensions rather than specific craniofacial structures. This may ultimately suggest that different genes are involved in controlling dimension vs structures. CONCLUSIONS: Our phenotypic dissection of Class III malocclusion established distinct subtypes in a large sample of patients and will ultimately provide the basis for future familial studies to identify a causative gene.

Common factors among the major malocclusions.

Dental practitioners tend to classify malocclusions in a schematic fashion often forgetting the full possibilities of characteristics related to a particular situation or malocclusion. This paper is designed to clarify and describe the different malocclusions, stressing the multiple faces of Class I in the mixed dentition based on the previous work of Drs. Anderson, Dewey and Sim. The description of all the major malocclusions is included with their facial, skeletal, dental and functional characteristics. Guidelines for diagnosis and treatment planning with a summary of possible difficulties in treatment are also discussed.

A new approach of assessing sagittal discrepancies: the Beta angle.

An accurate anteroposterior measurement of jaw relationships is critically important in orthodontic diagnosis and treatment planning. The angular and linear measurements that have been proposed can be inaccurate because they depend on various factors. The purpose of this study was to establish a new cephalometric measurement, named the Beta angle, to assess the sagittal jaw relationship with accuracy and reproducibility. This angle uses 3 skeletal landmarks-point A, point B, and the apparent axis of the condyle-to measure an angle that indicates the severity and the type of skeletal dysplasia in the sagittal dimension. Seventy-six pretreatment cephalometric radiographs of white patients were selected on the basis of 4 criteria that indicate a normal Class I skeletal pattern; the mean and the SD for the Beta angle were calculated. This group was compared with Class II and Class III skeletal pattern groups. After using the 1-way analysis of variance and the Newman-Keuls test and running receiver-operating-characteristics curves, we obtained results that showed that a patient with a Beta angle between 27 degrees and 35 degrees can be considered to have a Class I skeletal pattern. A more acute Beta angle indicates a Class II skeletal pattern, and a more obtuse Beta angle indicates a Class III skeletal pattern.