Relationship among malocclusion, number of occlusal pairs and mastication

This study evaluated the relationship among malocclusion, number of occlusal pairs, masticatory performance, masticatory time and masticatory ability in completely dentate subjects. Eighty healthy subjects (mean age = 19.40 ± 4.14 years) were grouped according to malocclusion diagnosis (n = 16): Class I, Class Class II-2, Class III and Normocclusion (control). Number of occlusal pairs was determined clinically. Masticatory performance was evaluated by the sieving method, and the time used for the comminute test food was registered as the masticatory time. Masticatory ability was measured by a dichotomic self-perception questionnaire. Statistical analysis was done by one-way ANOVA, ANOVA on ranks, Chi-Square and Spearman tests. Class II-1 and III malocclusion groups presented a smaller number of occlusal pairs than Normocclusion (p < 0.0001), Class I (p < 0.001) and II-2 (p < 0.0001) malocclusion groups. Class I, and III malocclusion groups showed lower masticatory performance values compared to Normocclusion (p < 0.05) and Class II-2 (p < 0.05) malocclusion groups. There were no differences in masticatory time (p = 0.156) and ability (&#967;2 = 3.58/p= 0.465) among groups. Occlusal pairs were associated with malocclusion (rho = 0.444/p < 0.0001) and masticatory performance (rho = 0.393/p < 0.0001), but malocclusion was not correlated with masticatory performance (rho = 0.116/p= 0.306). In conclusion, masticatory performance and ability were not related to malocclusion, and subjects with Class I, II-1 and III malocclusions presented lower masticatory performance because of their smaller number of occlusal pairs

Perbedaan Rasio Ukuran Mesiodistal Gigi (Bolton) Pada Maloklusi Klasifikasi Angle di SMPN 1 Salatiga Jawa Tengah

Width of mesiodistal tooth is one of the factors that need to be considered in orthodontic treatment. Mesiodistal tooth size discrepancy of the arch could be the causes of malocclusion. To estimate normal size of mesiodistal tooth used the ratio Bolton i.e. Bolton Overall Ratio (BOR) and Bolton Anterior Ratio (BAR). The purpose of this research is to know the difference between Bolton Overall Ratio and Bolton Anterior Ratio in relation to the first molar permanent tooth malocclusion of Angle classification at SMPN 1 Salatiga Central Java. This is an analytical observational with cross sectional design survey. Samples consisted of 51 people with fully erupted and complete permanent dentition form first molar to first molar who were registered by purposive sampling methode. The difference of ratio Bolton on malocclusion of Angle classification were tested using tests analysis of one-way Anova post hoc Bonferroni. Results of the analysis of BAR value was ranged between 72.41 and 90.14, with mean value 79.95±3.30. The lowest BAR was in Class II and the highest was in Class III. The BOR value was ranged between 87.54 and 97.38, with mean value 92.78±2.04. The lowest BOR was in Class II and the highest was in Class III. The result of one-way Anova analysis showed the p value in BAR toward malocclusion was 0,030, and BOR toward malocclusion was 0,165. It can be concluded that there was a difference means of Bolton Anterior Ratio (BAR) to malocclusion, but there is no difference means of Bolton Overall Ratio (BOR) to malocclusion. Analysis using post hoc Bonferroni showed that BAR differences was only in Class I and Class II Angle classification of malocclusion

Orthodontic treatment of nongrowing patient with class II division 2 malocclusion by Herbst appliance

Background. Inheritance is most casual etiological factor of Class II division 2 malocclusion. This kind of malocclusion is very difficult for treatment specially in older patients. Case report. In the female patient, 20 years old, at the beginning of the treatment at the School of Dentistry in Belgrade, lateral cephalogram showed skeletal and dentoalveolar Class II division 2 malocclusion. She was in the Herbst treatment for 8 months and 12 months more with a fixed multibracket appliance. The measurements were performed on lateral cephalograms before and after the treatment: ii, is, mi, ms, Pg and ss. The distance from these points to occlusal perpendicular line (Olp) were measured and compared from cephalogram before to cephalogram after the treatment. Temporomandibular joint (TMJ) tomograms were compared from before and after the treatment by superimposition. Correction was found in molar and incisor relation, overjet and overbite. There were found sagital skeletal changes and soft tissue profile improvement. Conclusion. Herbst appliance is effective in the treatment of Class II malocclusions, even in adult patients. Dental and skeletal changes as a result of Herbst treatment could be good choice instead of camouflage orthodontics or surgical decision

Prevalence of Malocclusion in Patients with Down’s Syndrome

U osoba s Downovim sindromom pronađene su znatne promjene koje zahvaćaju kranioorofacijalno područje. Ovim radom željela se utvrditi čestoća pojedinih vrsta ortodontskih anomalija u tih ispitanika. U tu svrhu pregledano je 112 ispitanika s citogenetski potvrđenom dijagnozom Downova sindroma. Svi ispitanici podvrgnuti su potpunom stomatološkom pregledu. Za određivanje ortodontske anomalije uporabljena je sljedeća klasifikacija: kompresije, anomalija preranoga gubitka, progenija, otvoreni zagriz, pokrovni zagriz, jednostrani unakrsni zagriz, te obostrani unakrsni zagriz. U 92% ispitanika postojala je ortodontska anomalija. Najzastupljenija je bila progenija, i to u 43,8% ispitanika. Zbijenost i jednostrani križni zagriz pronađeni su svaki od njih u 17% ispitanika. Obostrani križni zagriz pronađen je u 5,4% ispitanika, anomalija preranoga gubitka samo u 1% ispitanika, a pokrovni zagriz nije pronađen ni u jednome slučaju.Significant alterations of the cranio-orofacial region have been observed in subjects with Down’s syndrome. The aim of this study was to assess the frequency of particular orthodontic malocclusion in these subjects. A group of 112 subjects with cytogenetically confirmed diagnosis of Down’s syndrome was examined. All the subjects underwent a complete dental examination. The following classification was used to determine malocclusion of crowding, premature tooth loss, class III malocclusion, open bite, class II division 2 malocclusion, unilateral cross bite and bilateral cross bite. Clipper language programs were designed for data processing. Malocclusion was found in 92% of the subjects. Class III malocclusion was most frequently observed (43.8%). Crowding and unilateral cross bite were found in 15% of the subjects respectively. Bilateral cross bite was present in 5.4% of the subjects. Premature tooth loss was observed in only 1% of the subjects whereas class II division 2 malocclusion was not recorded in any of the subjects examined

Perbedaan Lebar Lengkung Gigi pada Maloklusi Klasifikasi Angle di SMPNI Salatiga Jawa Tengah

Background: Dental arch could influence several factors concerned to such as available space, aesthetic, and teeth stability. Some researchers claimed that there was differences of dental arch width on malocclusion Angle classification while some others said the opposite. By knowing dental arch width, it can help practitioners in orthodontics, prosthodontics, and anthropology to understand the dimension of dental arch. Purpose : The purpose of this research is to know the difference of dental arch width on different malocclusion Angle classification at SMPN 1 Salatiga, Central Java. Method: This was analytical observational study with cross sectional survey design. 51 samples were choosen by purposive sampling method, with determined criteria as has to have complete permanent teeth from right first molar to left first molar. Dental arch width measurement was done at particular point, there were intercanine, first interpremolar, second interpremolar, first intermolar, first intermolar second point, both maxillary and mandibular. One way Anova test was applied to understand the differences between classes. Result: The result showed that maxillary teeth with p<0.05 was detected at the second point-first intermolar. For mandibular, p<0.05 were detected on first interpremolar, second interpremolar, and first intermolar. Comparing mean value of the point of malocclusion-angle classification, it was showed that dental arch width of class I was narrower than class II, while class I and class II were wider than class III. Conclusion: There were differences of dental arch width on malocclusion Angle classification

A cephalometric comparison of twin block and bionator appliances in treatment of class II malocclusion

Class II malocclusion is one of the most common orthodontic problems. In cases of class II malocclusion with mandibular deficiency, functional appliances often are used with the intent of stimulating mandibular growth. Bionator and twin block are two of the more popular functional appliances. The aim of this study was to compare the treatment outcomes of these two appliances using cephalometric radiographs. Cephalometric radiographs of 33 patients who had class II division I malocclusion, before and after treatment were digitalized. The mean changes in twin block and bionator groups were compared using independent t test. Twin block and bionator showed no statistically significant differences in cephalometric parameters except for ANB, NA-Pog, Basal and Ar-Go-Me angles. There were no statistically significant differences in dentoalveolar and mandibular position between twin block and bionator (p>0.1). Twin block was more efficient in inhibition of forward movement of maxilla (p<0.1)

Angle's Class II malocclusion treated without extractions and with growth control

Angle's Class II malocclusion is defined according to the anteroposterior molar relationship with or without a discrepancy between basal bones. Maxillary protrusion and mandibular retrusion are included in this class. When orthodontic treatment starts at an early age, it is possible to affect growth of both basal bones and the dentoalveolar region, which helps to correct tooth positioning in the corrective phase. This report describes the treatment of a case of Angle Class II, division 1 malocclusion that was presented to the Committee of the Brazilian Board of Orthodontics and Facial Orthopedics (BBO) as partial fulfillment of the requirements to obtain the BBO Diploma. The case was representative of category 1, that is, Angle Class II malocclusion treated without extractions and with growth control.A má oclusão Classe II de Angle é definida pela relação anteroposterior dos molares, que pode estar acompanhada por um degrau aumentado entre as bases ósseas. Estão incluídos nesse padrão os portadores de protrusão maxilar e/ou deficiência mandibular. O tratamento ortodôntico precoce permite intervenção na direção de crescimento, tanto nas bases ósseas quanto na região dentoalveolar, o que favorece a correção do posicionamento dentário na fase corretiva. O presente relato descreve o tratamento de um caso de má oclusão Classe II, divisão 1, de Angle, que foi apresentado à Diretoria do Board Brasileiro de Ortodontia e Ortopedia Facial (BBO) como parte dos requisitos para a obtenção do título de Diplomado pelo BBO. O caso foi avaliado como representante da Categoria 1, ou seja, má oclusão Classe II de Angle tratada sem extrações dentárias e com controle de crescimento.UNIFESPUSPBoard Brasileiro de OrtodontiaOrtopedia Facial BBOUNIFESPSciEL

Oral myofunctional and electromyographic evaluation of the orbicularis oris and mentalis muscles in patients with class II/1 malocclusion submitted to first premolar extraction

OBJECTIVE: The aim of this study was to assess the presence of oral myofunctional alterations before and after first premolar extraction in Class II/1 malocclusion patients that could endanger the long-term dental arch stability. MATERIAL AND METHODS: The study was performed by means of morphological, functional and electromyographic analyses in 17 Class II/1 malocclusion patients (group T) and 17 Class I malocclusion patients (group C -control), both groups with 12-30-year age range (mean age: 20.93 ± 4.94 years). RESULTS: Data analyzed statistically by Student's t-test showed a significant decrease (p0.05). The Kruskal-Wallis test analyzed data from lip posture (orbicularis oris muscle) at rest and during swallowing, as well as the mentalis muscle behavior during the above-mentioned function, not showing statistically significant differences (p>0.05) after treatment (groups T1 and T2). However, group T differed significantly from group C (p<0.05). Lip posture during swallowing showed statistically significant differences (p<0.05) for subjects submitted to orthodontic therapy when compared to data acquired before the treatment. The electromyographic analysis confirmed these data. CONCLUSIONS: Found myofunctional alterations observed after the orthodontic treatment in Class II/1 malocclusion seemed to jeopardize the long-term orthodontic stability, making recurrence possible.Federal University of São PauloUniversity of Western São Paulo StateState University of CampinasUNIFESPSciEL

Lateral cephalometric analysis of asymptomatic volunteers and symptomatic patients with and without bilateral temporomandibular joint disk displacement

Few studies of dentofacial and orthodontic structural relationships relative to temporomandibular joint (TMJ) dysfunction have been reported. We undertook this investigation to determine any correlation of orthodontic and dentofacial characteristics with TMJ bilateral disc displacement. The population of patients was selected from a TMJ clinic where a control group of asymptomatic volunteers had been previously established and standardized. Differences in skeletal structural features were determined among three study groups: (1) asymptomatic volunteers with no TMJ disk displacement, (2) symptomatic patients with no TMJ disc displacement, and (3) symptomatic patients with bilateral TMJ disk displacement. Thirty-two asymptomatic volunteers without disk displacement (25 female, 7 male) were compared with the same number each of symptomatic patients without TMJ disk displacement and symptomatic patients with bilateral TMJ disk displacement. All subjects had undergone a standardized clinical examination, bilateral TMJ magnetic resonance imaging, and lateral cephalometric radiographic analysis. The groups were matched according to sex, TMJ status, age, and Angle classification of malocclusion. Seventeen lateral cephalometric radiographic cranial base, maxillomandibular, and vertical dimension variables were evaluated and compared among the study groups. The mean angle of SNB, or the intersection of the sella-nasion plane and the nasion–point B line (indicating mandibular retrognathism relative to cranial base), of the symptomatic patients-with-displacement group was significantly smaller than that in the asymptomatic volunteers and symptomatic patients without bilateral disk displacement (p \u3c 0.05). Female subjects showed smaller linear measurements of mandibular length, lower facial height, and total anterior facial height than male subjects in all three groups (p \u3c 0.05). The mean angle of ANB, or the intersection of the nasion–point A and nasion–point B planes (indicating retrognathism of mandible relative to maxilla), was significantly greater in female than in male subjects, in all groups (p \u3c 0.05). Symptomatic patients with bilateral disk displacement had a retropositioned mandible, indicated by a smaller mean SNB angle compared with that in asymptomatic volunteers and symptomatic patients with no disk displacement on either side. Lateral cephalometric radiographic assessment may improve predictability of TMJ disk displacement in orthodontic patients but is not diagnostic; nor does the assessment explain any cause-and-effect relationship. (Am J Orthod Dentofacial Orthop 1998;114:248-55.

Using Networks To Understand Medical Data: The Case of Class III Malocclusions

A system of elements that interact or regulate each other can be represented by a mathematical object called a network. While network analysis has been successfully applied to high-throughput biological systems, less has been done regarding their application in more applied fields of medicine; here we show an application based on standard medical diagnostic data. We apply network analysis to Class III malocclusion, one of the most difficult to understand and treat orofacial anomaly. We hypothesize that different interactions of the skeletal components can contribute to pathological disequilibrium; in order to test this hypothesis, we apply network analysis to 532 Class III young female patients. The topology of the Class III malocclusion obtained by network analysis shows a strong co-occurrence of abnormal skeletal features. The pattern of these occurrences influences the vertical and horizontal balance of disharmony in skeletal form and position. Patients with more unbalanced orthodontic phenotypes show preponderance of the pathological skeletal nodes and minor relevance of adaptive dentoalveolar equilibrating nodes. Furthermore, by applying Power Graphs analysis we identify some functional modules among orthodontic nodes. These modules correspond to groups of tightly inter-related features and presumably constitute the key regulators of plasticity and the sites of unbalance of the growing dentofacial Class III system. The data of the present study show that, in their most basic abstraction level, the orofacial characteristics can be represented as graphs using nodes to represent orthodontic characteristics, and edges to represent their various types of interactions. The applications of this mathematical model could improve the interpretation of the quantitative, patient-specific information, and help to better targeting therapy. Last but not least, the methodology we have applied in analyzing orthodontic features can be applied easily to other fields of the medical science.</p