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1.
The aim of the study was to assess the prevalence of malocclusion in a population of Bogotanian children and adolescents in terms of different degrees of severity in relation to sex and specific stages of dental development, in order to evaluate the need for orthodontic treatment in this part of Colombia. A sample of 4724 children (5-17 years of age) was randomly selected from a population that attended the Dental Health Service; none had been orthodontically treated. Based on their dental stages the subjects were grouped into deciduous, early mixed, late mixed and permanent dentition. The registrations were performed according to a method by Bj?rk et al. (1964). The need for orthodontic treatment was evaluated according to an index used by the Swedish National Board of Health. The results showed that 88 per cent of the subjects had some type of anomaly, from mild to severe, half of them recorded as occlusal anomalies, one-third as space discrepancies, and one-fifth as dental anomalies. No clear sex differences were noted, except for maxillary overjet, spacing, tooth size (all more frequent in boys), and crowding (more frequent in girls). Occlusal anomalies and space discrepancies varied in the different dental developmental periods, as did tipped and rotated teeth. Little need for orthodontic treatment was found in 35 per cent and moderate need in 30 per cent. A great need was estimated in 20 per cent, comprising children with prenormal occlusion, maxillary overjet, or overbite (> 6 mm), posterior unilateral crossbite with midline deviation (> 2 mm), severe crowding or spacing, congenitally missing maxillary incisors, impacted maxillary canines or anterior open bite (> 3 mm in the permanent dentition). Urgent need for treatment was estimated to be 3 per cent, comprising subjects with extreme post- and pre-normal occlusion, impacted maxillary incisors or extensive aplasia.  相似文献   

2.
In Class III malocclusion, the overjet is reduced and may be reversed, with one or more incisor teeth in lingual crossbite. In the early mixed dentition, and in older patients with mild skeletal discrepancies, orthodontic treatment usually involves proclining the maxilliary anterior teeth into positive overjet. When the permanent dentition has established, orthodontic therapy is usually aimed at compensating for the underlying mild-moderate Class III skeletal discrepancy by proclining and retroclining the maxillary and mandibular incisors, respectively. In contrast, adolescent and non-growing patients with severe Class III skeletal discrepancies require a combination of orthodontic treatment and orthognathic surgery to correct the underlying skeletal pattern. Adolescent patients with moderately severe skeletal discrepancies require careful treatment planning because they are often at the limits of orthodontic compensation, and further mandibular growth may prevent a stable Class I occlusion from being maintained with growth. In this situation, treatment should be limited to aligning the maxillary arch, accepting that orthognathic surgery will be required to correct the underlying Class III skeletal discrepancy when skeletal growth has been completed. This article will inform dental professionals about the aetiology, assessment, diagnosis and treatment of patients with Class III malocclusions. Specifically, the types of orthodontic treatment that can be completed at the various stages of dental development and skeletal growth will be discussed.  相似文献   

3.
Meeting Reports     
Abstract

This article describes treatment of a patient presenting with a class II malocclusion, maxillary and mandibular crowding, posterior crossbite and an increased deep bite, where the specific treatment goals were achieved in the early mixed dentition by only working on the primary teeth. A Haas-type rapid maxillary expansion (RME) appliance was modified to be anchored on the primary second molars and canines and activated once a day, with each activation equal to 0.20 mm. The appliance was blocked after 30 days and left as a retainer. After 6 months, the RME appliance was removed and bands were cemented to the primary second molars in order to apply traction with headgear. After complete eruption of the mandibular central and lateral incisors, sequential slicing of the lower primary teeth was performed to transfer the leeway space from the distal to the mesial part of the arch. When the patient had entered the permanent dentition, a dental class I relationship was achieved, the crossbite corrected and the crowding improved. The overjet and overbite were also improved. No permanent teeth were involved during this phase of treatment. The outcome of this case report shows that it is possible to work only on primary teeth in the mixed dentition and this can be an effective way to correct a class II malocclusion with deep bite, posterior crossbite and maxillary and mandibular crowding.  相似文献   

4.
PURPOSE: To know the prevalence of malocclusal traits and their correlation in Italian mixed dentition children. MATERIALS AND METHODS: A sample of 1,198 children 7 to 11 years old, who had never undergone orthodontic treatment, were included in the Italian Oral Health of Schoolchildren of the Abruzzo Region (OHSAR) Survey. Canine and molar classes, overbite, overjet, dental crowding, maxillary midline diastema, crossbite and scissorbite were recorded. The canine and molar classes were considered as dependent variables, and their separate correlations with all of the other occlusal traits were analysed by multivariate methods. RESULTS: Over 90% of the children showed at least one malocclusal trait; the mean +/- SD of malocclusal traits was 3.5 +/- 1.8. Gender did not affect the prevalence of any malocclusal traits. Dental class II was correlated with increased overbite and overjet, and negatively correlated with the maxillary midline diastema; dental class III was correlated with decreased overbite and overjet, and crossbite. Asymmetrical dental class was correlated with increased overjet and crossbite. Dental crowding showed very little correlation. CONCLUSIONS: The prevalence of malocclusal traits in Italian children is very high, and more effort is needed to implement early interventions, including close monitoring and modifications of lifestyle.  相似文献   

5.
Mandibular anterior crowding is identified as the discrepancy between mesiodistal tooth widths of four permanent incisors and available space in the alveolar process. However, incisor crowding is not merely a tooth-arch size discrepancy. Many variables such as direction of mandibular growth, early loss of deciduous molars, the oral and perioral musculature and incisor and molar inclination can be associated with crowding. Only few studies evaluated the relationship between mandibular anterior crowding and cephalometric measurements in the early mixed dentition. It was the aim of this study to search for dentofacial factors that might be associated with mandibular crowding in the early mixed dentition. Lateral cephalograms and dental casts of 60 children (33 girls, 27 boys) were evaluated. It was determined that patients with crowding had smaller lower incisor to NB angles, maxillary skeletal lengths, mandibular skeletal length, and mandibular dental measurements. They also had greater interincisal angles, overjet, overbite, and Wits appraisal measurements. Significant inverse correlations were found between crowding and SNB, lower incisor to NB angle, anterior cranial length, mandibular length, maxillary length, mandibular dental measurement and direct correlations between crowding and interincisal angle, overjet, overbite, and FMIA. According to these results, we conclude that crowding of the mandibular incisors is not only a tooth-arch size discrepancy. Dentofacial characteristics also contribute to this misalignment.  相似文献   

6.
The aim of this study was to investigate the relation between occlusal factors: Angle classification, overbite, overjet, openbite, anterior and posterior crossbite, scissors bite or buccal crossbite and lateral openbite--and the presence of mandibular dysfunction in a sample of 359 Turkish children with mixed and permanent dentition. Z Test was used to compare the results. It was found that, Class III malocclusion in the permanent dentition and openbite, overbite = 0, overjet = 0, anterior-posterior crossbite in the mixed dentition were related with TMD.  相似文献   

7.
The purpose of this study was to investigate secular changes that may have occurred in dental arch dimensions by comparing a sample of contemporary North American white children (born between 1992 and 1995) in the primary dentition to those children found in an earlier study of North American white children (born between 1946 and 1948). The sample of contemporary children has been followed prospectively since birth and was assessed at 4(1/2) to 5 years of age. Data for the historic sample were obtained from 5-year-old children who were enrolled in the Iowa Growth Study. The 2 samples were similar in terms of geographic location, racial and ethnic backgrounds, and socioeconomic status. To further enhance the comparison and to match the 2 groups, the 2 samples were restricted to white children with a normal overjet (<4 mm) and normal anteroposterior molar relationship, no anterior open bite, and no crossbite. In addition, individuals were excluded if any permanent teeth were erupted. Measurements of maxillary and mandibular arch lengths and intercanine and intermolar arch widths were made, with measurements of overjet and overbite. The results indicated that maxillary and mandibular arch lengths in both sexes were significantly shorter in the contemporary sample; all arch widths were significantly smaller in contemporary boys, but not in girls. These findings suggest that average arch dimensions may be smaller in contemporary children than in past generations. Further research is needed to determine whether smaller arch dimensions are associated with more crowding in the primary, mixed, and permanent dentitions.  相似文献   

8.
BACKGROUND: Studies dating to the 1870s have demonstrated that long-term nonnutritive sucking habits may lead to occlusal abnormalities, including open bite and posterior crossbite. However, little is known as to whether habits of shorter durations have lasting effects. METHODS: The authors collected longitudinal data on nonnutritive sucking among children through a series of questionnaires regularly completed by parents. Researchers examined the children at ages 4 to 5 years and obtained study models. The models were measured for dental arch parameters (including arch width, arch length and arch depth) and assessed for overjet, overbite and posterior crossbite. The authors compared the dental arch and occlusal conditions among groups of children with nonnutritive sucking habits of different durations. RESULTS: Children with nonnutritive sucking habits that continued to 48 months of age or beyond demonstrated many significant differences from children with habits of shorter durations: narrower maxillary arch widths, greater overjet and greater prevalence of open bite and posterior crossbite. In addition, compared with those who ceased their habit by 12 months of age, those with habits at 36 months of age had significantly greater mandibular canine arch widths, maxillary canine arch depths and overjet, while those with habits at 24 months and 36 months had significantly smaller palatal depths. Prevalence of anterior open bite, posterior crossbite and excessive overjet (> 4 millimeters) increased with duration of habits. CONCLUSIONS: While continuous nonnutritive sucking habits of 48 months or longer produced the greatest changes in dental arch and occlusal characteristics, children with shorter sucking durations also had detectable differences from those with minimal habit durations. CLINICAL IMPLICATIONS: It may be prudent to revisit suggestions that sucking habits continued to as late as 5 to 8 years of age are of little concern.  相似文献   

9.
Brodie bite is a comparatively rare type of malocclusion found in primary and mixed dentition. It not only adversely affects chewing and muscle functions, but also impairs normal growth and development of the mandible. This report describes the therapeutic results of a patient with bilateral Brodie bite in early mixed dentition after using a bonded constriction quad-helix appliance. The patient, a boy aged 9 years and 2 months, first visited our hospital after occlusal abnormality in the molar region was detected at a local dental clinic. Case analysis resulted in a diagnosis of bilateral Brodie bite with slight mandibular retrognathism. Treatment objectives were to reduce the arch width of the maxillary dentition and expand the mandibular arch in order to establish and stabilize molar occlusion and to achieve a Class I molar relation and appropriate overbite and overjet. Treatment comprised covering the occlusal surface of the maxillary molars with resin and attaching a bonded constriction quad-helix appliance joined with a 0.040-inch quad-helix wire. A bi-helix appliance was also fixed to the mandibular dentition. Brodie bite visibly improved after 5 months. Cervical headgear was then fitted and the patient observed until eruption of the permanent dentition was complete. Class I molar relation was achieved after 2 years and 6 months, although spacing remained in the maxillary and mandibular dentitions. Treatment of bilateral Brodie bite in mixed dentition by means of a bonded constriction quad-helix appliance attached to the maxillary dentition enabled effective bite opening and reduction in the width of maxillary arch independent of the patient's cooperation, providing good therapeutic outcome in a short time period.  相似文献   

10.
This study investigated the early effects on mandibular incisor irregularity and rotation together with dental arch dimensions of the extraction of four deciduous canines. Children, during early mixed dentition, were randomized into one extraction (n = 32) and one control (n = 41) group. Dental casts from baseline (T0) and 1 year follow-up (T1) were used to evaluate changes in the irregularity index and in mandibular incisor rotation, dental arch dimensions, overjet, and overbite. Median mandibular incisor irregularity decreased over time, significantly more in the extraction than the control group (1.2 versus 0.7 mm; P < 0.01), with wide ranges in both groups. Rotational changes greater than 10 degrees for lateral incisors were twice as common in the extraction group (42 versus 20 per cent; P < 0.01). Central incisors displayed only minor changes in both groups. The correlation between changes in irregularity index and changes in incisor rotation was weak in both groups (r(s) < 0.3 not significant). According to professional assessment of overall alignment, 84 per cent in the extraction group versus 34 per cent in the control group (P < 0.001) improved from T0 to T1. A significant decrease in maxillary and mandibular arch length and circumference from T0 to T1 was recorded in the extraction group (1.3, 1.1 mm and 2.4, 2.0 mm, respectively; P < 0.001), while arch dimensions were preserved in the control group. To conclude, 1 year after extraction of the deciduous canines, small improvements in mandibular incisor alignment were seen, together with reduced arch dimensions. Little's index underestimated malalignment related to tooth rotation.  相似文献   

11.
The aim of this study was to investigate the relationship between occlusal factors (overjet, overbite, Angle's Classification of molars and cuspids, the relationship of the primary molars, openbite, lateral openbite, scissorbite and crossbite) and bruxism in permanent and mixed dentition in Turkish children. For this reason 182 children with mixed dentition and 212 children with permanent dentition were included in this study. Occlusal conditions were examined clinically and bruxism was assessed by using interview and questionnaires. Z Test was used to compare the results. It was found that in both dentitions some occlusal factors related with bruxism (overjet > 6 mm, overbite > 5 mm, negative overjet, openbite in permanent dentition; overjet > 6 mm, overbite > 5 mm, scissorbite, anterior-posterior multiple teeth crossbite, Angle Class I occlusion in mixed dentition.  相似文献   

12.
Objective:To compare and evaluate the stability of correction of anterior crossbite in the mixed dentition by fixed or removable appliance therapy.Material and Methods:The subjects were 64 consecutive patients who met the following inclusion criteria: early to late mixed dentition, anterior crossbite affecting one or more incisors, no inherent skeletal Class III discrepancy, moderate space deficiency, a nonextraction treatment plan, and no previous orthodontic treatment. The study was designed as a randomized controlled trial with two parallel arms. The patients were randomized for treatment with a removable appliance with protruding springs or with a fixed appliance with multibrackets. The outcome measures were success rates for crossbite correction, overjet, overbite, and arch length. Measurements were made on study casts before treatment (T0), at the end of the retention period (T1), and 2 years after retention (T2).Results:At T1 the anterior crossbite had been corrected in all patients in the fixed appliance group and all except one in the removable appliance group. At T2, almost all treatment results remained stable and equal in both groups. From T0 to T1, minor differences were observed between the fixed and removable appliance groups with respect to changes in overjet, overbite, and arch length measurements. These changes had no clinical implications and remained unaltered at T2.Conclusions:In the mixed dentition, anterior crossbite affecting one or more incisors can be successfully corrected by either fixed or removable appliances with similar long-term stability; thus, either type of appliance can be recommended.  相似文献   

13.
In a recent study, it was reported that maxillary and mandibular arch lengths were significantly shorter in a sample of contemporary children in the deciduous dentition compared with a historical sample from about 50 years earlier. The purpose of this study was to describe secular changes that might have occurred in tooth sizes and tooth size-arch length relationships in the same cohorts of contemporary and historical North American white children in the deciduous dentition. The 2 samples were similar in terms of geographic location, racial and ethnic backgrounds, and socioeconomic status. Both samples were restricted to white children with a normal overjet (<4 mm) and a normal anteroposterior molar relationship, no anterior open bite, and no crossbite. In addition, subjects were excluded if any permanent teeth were erupted. Measurements of mesiodistal tooth sizes and arch lengths of maxillary and mandibular arches were made, and tooth size-arch length discrepancies (TSALD) were determined. The results indicated that tooth sizes were generally similar in the 2 cohorts but slightly larger in contemporary children. Crowding, as measured by TSALD, was found to be common in the mandibular arch for contemporary children in the deciduous dentition of both boys and girls. Moreover, crowding was much more common and severe in contemporary children compared with children in the historical cohort. Further research is needed to determine whether the increase in mandibular crowding in the deciduous dentition will continue to be observed in the mixed and permanent dentitions and to further establish these possible secular trends.  相似文献   

14.
Ninety-three per cent of all 12-year old patients at a clinic in western Sweden accepted an invitation to take part in a dental examination in order to evaluate early orthodontic treatment. Treatment in the primary or mixed dentition periods should aim at creating normal craniofacial, occlusal and dental development and, if possible, at reducing the need for later, more complicated treatment. The treatment success was low regarding overjet correction but fairly good with regard to diagnosis and treatment of crossbite/forced occlusion, ectopic eruption and congenitally missing teeth. Whether correction of crossbite had reduced crowding was impossible to evaluate in this study. However, relatively few subjects with a history of crossbite correction desired alignment of teeth. The study confirmed earlier observations that TMD prevention is not a major motivating factor for orthodontic treatment. The majority of the children, including those desiring treatment, judged their dental appearance to be fairly average. The dentists more often than the children regarded the subjects' appearance to be better than average. Prediction of later orthodontic treatment, recorded at the age of 14 years, turned out to have a weak association to evaluation of aesthetics both by the children and the dentists. Nor did recording of TMD improve prediction. The study confirms earlier observations that discussions about orthodontic treatment on mainly aesthetic grounds ought to be postponed well into the permanent dentition period, and by attempting to avoid "making the normal abnormal".  相似文献   

15.
This study analyzed the occlusions of 489 children at the onset of the mixed dentition period (mean age 5.1 years, range 4.0-7.8 years). These children participate in an ongoing clinical trial that is investigating the effects of orthodontic intervention in the early mixed dentition. The aim was to report the occlusal findings at the baseline. The frequencies of mesial step, flush terminal plane, and distal step were 19.1%, 47.8%, and 33.1%, respectively. The canine relationship was Class I in 46.1%, Class II in 52.4%, and Class III in 1.5% of the sides examined. An asymmetrical canine relationship was found in 30.1% of the children, significantly more often on the right side than on the left (P <.001). Overjet ranged from -2 to +10 mm with a mean of 2.9 mm. Overbite ranged from -5 to +8 mm with a mean of 2.8 mm. Excessive (> or =4 mm) overjet was found in 26.7% and overbite in 33.8% of the children; in 15.5% of the children, both variables were 4 mm or more. Anterior crowding was detected in the maxillary arch in 11.6% and in the mandibular arch in 38.9% of the children. Girls showed mandibular crowding more often than boys (P <.01). A posterior crossbite was found in 7.5% of the children, unilaterally in 6.4% and bilaterally in 1.1%. Scissors-bite was detected in 1.1% and an anterior crossbite in 2.2% of the children. The mean maximal opening was 40.3 mm. Joint sounds were registered in 5.2% of the children. The prevalence of malocclusion was between 67.7% and 92.7%, depending on the values of unacceptable parameters used for each occlusal characteristic.  相似文献   

16.
This survey was undertaken to assess the orthodontic treatment need in a sample of 9- to 12-year-old French children (mean age: 9.77 years; standard deviation: 0.84) attending 12 different schools in the same geographic area of Ile de France. Two examiners used the Index of Orthodontic Treatment Need (IOTN) in order to estimate treatment need. Five hundred and eleven children (268 males, 243 females) who had not previously received orthodontic treatment were examined. Two examiners, who had been previously trained in the use of occlusal indices, screened all the schoolchildren. No radiographs, study casts, or previously written records of the children were used; the IOTN was calculated from direct examination. Qualitative data were analysed using the chi-square test to determine differences in treatment need between subgroups of subjects, and kappa("kappa") statistics to analyse the findings. A correlation coefficient was used to compare professional assessments. Twenty-one per cent of the children presented an objective need for orthodontic treatment, 28 per cent had crowding, 28 per cent an increased overjet, and 15 per cent an increased overbite. The dental health component (DHC) of the IOTN was found to be reliable and simple to use. The malocclusion status of French schoolchildren was lower than that recorded in epidemiological studies of European children.  相似文献   

17.
We performed measurement using a 3-dimensional measurement system in study models of children with anterior crossbite in the primary dentition treated using a chin cap and lingual arch, and evaluated changes in the dentition and occlusion after treatment based on measurement values and also using wire frame models. Comparing with the situation before treatment, the overbite of anterior teeth shows improvement to become shallow and the terminal plane becomes vertical type and the occlusal plane becomes flatter. Labioclination of upper anterior teeth, linguoclination of lower anterior teeth and backward movement of lower dentition are observed. Occlusal view shows that both upper and lower dental arch become semicircular configuration. The width, depth and height of the post-treatment dentition became closer to the standard values. Chin cap and lingual arch treatment for anterior crossbite during early childhood is effective, and also helpful in the normal development of occlusion in children.  相似文献   

18.
The treatment of a patient with a skeletal Class II Division 1 malocclusion, with excessive overjet, complete overbite, airway obstruction, and severe arch length deficiency in the mandibular dental arch, is presented. The maxilla was narrow compared with the mandible, and the posterior teeth were compensated, with the maxillary teeth inclined buccally and the mandibular teeth inclined lingually. The palatal vault was extremely high. Treatment included rapid palatal expansion to correct the transverse maxillary deficiency and Kloehn cervical headgear to correct the anteroposterior skeletal discrepancy. Long-term stability (12-year follow-up) is reported.  相似文献   

19.
AIM: The aim of this study is to provide basic data on the prevalence of malocclusions and orofacial dysfunctions in the primary and early mixed dentition, to examine occlusal relationships in their functional context, and to analyze the need for and potential of orthodontic prevention. SUBJECTS AND METHODS: Occlusal relationships and myofunctional status were evaluated in 766 children in the primary dentition and in 2,275 children in the early mixed dentition. Orthodontic findings in single jaws and intermaxillary occlusal relationships were clinically analyzed in all three dimensions. RESULTS: Normal occlusal relationships were found in 25.3% of children in the primary dentition. Frequency of children with normal dentitions fell significantly in the mixed dentition (7.3%). Prevalence of bilateral distoclusion increased significantly from the primary to the mixed dentition. Increased maxillary overjet was diagnosed in 49.3% and 59.0% of the children in the primary and mixed dentition, respectively. Prevalence of lateral crossbites increased significantly from primary to mixed dentition (7.2% vs. 12.0%). Deep bites and edge-to-edge bites were found significantly more often in the early mixed dentition. CONCLUSIONS: The significant increase in the prevalence of malocclusions between the primary and mixed dentition--distoclusion and lateral crossbite, and the impairment of vertical occlusal relationships in the mixed dentition in particular--reveal the need for orthodontic prevention. They highlight the absence of applied interceptive and early treatment measures in orthodontics. The indication system in current use for early orthodontic treatment here in Germany fails to fulfill the requirements for prevention-oriented dental care.  相似文献   

20.
目的:评价骨钉前方牵引治疗对生长发育期上颌后缩下颌前突型反[牙合]病例的矫治效果。方法:选择替牙晚期和恒牙早期骨性Ⅲ类错病例8例,男2例,女6例,年龄11~14岁,平均12.2岁。均为上颌发育不足并伴有下颌、下牙弓轻度前突的凹面型,在双侧上颌颧牙槽嵴区植入骨钉,骨钉与牵引面罩的牵引钩相连,与[牙合]平面成向前下30°夹角,力值维持在350g左右,每日戴用时间为10~12h。有3例恒牙早期病例因牙列拥挤或下牙弓前突,设计对称拔除了上、下颌第二或第三磨牙,植入下颌磨牙骨钉以牵引排齐内收下牙弓。结果:8例患者前方牵引5~10个月,平均7个月,均有效解除前牙反[牙合]。结论:应用骨钉做前方牵引,牵引力通过上颌骨阻力中心,不会致颌骨出现异常旋转。牵引力完全作用在颌骨上,避免了对牙齿产生副作用。骨钉还可用于牵引上下颌牙列远中移动,减少上前牙唇倾并增强前方牵引对下牙弓的矫治作用。  相似文献   

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