Long-term stability of anterior open bite closure corrected by surgical-orthodontic treatment

In adults, superior repositioning of posterior maxilla with or without mandibular surgery has become the treatment method of choice to close anterior open bite. Study aim was to examine the long-term stability of anterior open bite closure by superior repositioning of maxilla or by combining maxillary impaction with mandibular surgery. The sample comprised 24 patients who underwent anterior open bite closure by superior repositioning of maxilla (maxillary group, n = 12, mean age 29.3 years) or by maxillary impaction and mandibular osteotomy (bimaxillary group, n = 12, mean age 30.8 years). Lateral cephalograms were studied prior to surgery (T1), the first post-operative day (T2) and in the long term (T3, maxillary group mean 3.5 years; bimaxillary group mean 2.0 years). Paired and two-sample t-tests were used to assess differences within and between the groups. The vertical incisal bite relations were -2.6 and -2.2 mm at T1; 1.23 and 0.98 mm at T2; and 1.85 and 0.73 mm at T3 in the maxillary and bimaxillary groups. At T3, all subjects had positive overbite in the maxillary group, but open bite recurred in three subjects with bimaxillary surgery. For both groups, the maxilla relapsed vertically. Significant changes in sagittal and vertical positions of the mandible occurred in both groups. In the bimaxillary group, the changes were larger and statistically significant. In general, the maxilla seems to relapse moderately vertically and the mandible both vertically and sagittally, particularly when both jaws were operated on. Overbite seems to be more stable when only the maxilla has been operated on.     

Psychologic implications of surgical-orthodontic treatment in patients with anterior open bite

Two hundred eighty-two patients who received surgical-orthodontic treatment to correct anterior open bite were retrospectively evaluated by interview and questionnaires to determine the motivation and expectations before treatment, experience during treatment, psychosocial impact, functional and esthetic results, and satisfaction. All patients underwent a Le Fort I osteotomy, and 126 patients also received a bilateral sagittal split advancement osteotomy. The mean follow-up was 6 years. The most important reasons for treatment, as cited by the patients, were biting and chewing problems (28%), dissatisfaction with facial appearance (26%), and symptoms of temporomandibular joint (TMJ) dysfunction (21%). Patients with anterior open bite had a critical attitude toward facial appearance; therefore, esthetic aspects should be taken seriously. The expectations on chewing ability, phonetics, nasal passage, and facial appearance were met by the treatment; however, expectations on TMJ function, interincisal relationship, and biting ability were not completely fulfilled. There was a subjective improvement of TMJ sounds in 27% and a worsening in 14% of the patients. Dysesthesia of the infraorbital nerve was noticed in 4% of patients and of the mental or inferior alveolar nerve in 23% of the patients. Chewing and biting abilities improved in 53% and 73%, respectively. Facial appearance, self-confidence, and social interaction had improved. Patients had expected more information before and psychologic support after treatment. Despite the relapse of open bite in 20% of the patients, 75% were satisfied with the dental and 85% with the facial appearance.     

Skeletal morphologic features of anterior open bite

Lateral cephalograms of sixty patients with open bite and sixty untreated subjects who were determined clinically to have Class I normal occlusions were studied. The following six values were recorded: (1) ratio of posterior to anterior face height, (2) ratio of upper to lower face height, (3) Sn GoGn angle, (4) gonial angle, (5) SN-PP angle, and (6) PP-GoGn angle. Results were compared with previous studies. The constancy of the ratios and angles with age was tested and an attempt was made to separate the open-bite sample into skeletal and dentoalveolar groups. Results were generally consistent with those reported previously, except for the Sn PP angle, which was not significantly different from the normal group. In the open-bite sample the study showed a decrease in the ratio of PFH/AFH, a decrease in the ratio of UFH/LFH, and an increase in the other angles measured. Upon further division of the sample into mixed- and permanent-dentition groups, it was found that the angles and ratios remained relatively constant with age. An attempt to divide the open-bite sample into skeletal and dentoalveolar groups resulted in more extreme values for all the measurements made. The difficulty in differentiating between the two groups and the variability of dentoskeletal patterns in open bite is discussed.     

Long-term stability of anterior open bite extraction treatment in the permanent dentition.

The purpose of this study was to cephalometrically evaluate the long-term stability of anterior open bite extraction treatment in the permanent dentition after a mean period of 8.35 years. Cephalometric headfilms were obtained at pretreatment, posttreatment, and postretention stages from 31 patients who had undergone orthodontic treatment with fixed appliances. Two control groups were used. The first, with an age similar to that of the experimental group before treatment, was used only to characterize it. The second, with normal occlusion, was followed longitudinally for a period comparable with the posttreatment period and was used to compare changes during this period. The differences between the observation stages in the experimental group were analyzed with paired t tests, and the posttreatment changes were compared with the changes of the second control group with independent t tests. There was no statistically significant decrease of the obtained anterior overbite at the end of the posttreatment period. The primary factors that contributed to the nonsignificant decrease of the overbite were the normal vertical development of the maxillary and mandibular incisors, the smaller vertical development of the mandibular molars, and the consequent smaller increase in lower anterior face height, as compared with the control group in the long-term posttreatment period. Additionally, 74.2% of the sample had a "clinically stable" open bite correction.     

Skeletal class III and anterior open bite treatment with different retention protocols: a report of three cases

Abstract

The treatment of skeletal class III and anterior open bite can be unstable and orthodontists frequently observe relapse. Here, we report on the management of three patients with skeletal class III profiles and open bites treated by orthodontic camouflage. Each received a retention protocol involving the use of two separate appliances during the night and day accompanied by myofunctional therapy. Long-term follow-up revealed a stable outcome.     

Orthodontic treatment of anterior open bite

OBJECTIVE: To review the currently available treatment options of anterior open bite. METHODS: Search all major dental journals and literature on treatment and management of anterior open bite. Medline search (1960-2006). Literature and data on treatment and management of anterior open bite with keywords 'open bite', 'anterior open bite', 'orthodontic treatment', 'long face', 'vertical dentoalveolar problem' and 'vertical skeletal problem'. RESULTS: Over 50 articles were found and relevant information and data were reviewed by the authors. It was found that the multifactorial nature of anterior open bite makes its management difficult and various treatment modalities are being used. Clinicians must be able to diagnose the problem and choose the best treatment. CONCLUSION: Successful treatment of anterior open bite greatly relies on both diagnosis and therapeutics. Although there are many different treatment modalities available, stability after treatment is still a critical issue as evidence on long term stability of various treatment options is lacking. Thus, clinicians should pay more attention during retention phase and long-term studies on post-treatment changes and stability should be encouraged.     

前牙开(牙合)不同矫治设计的初步研究

目的 探讨前牙开不同的矫治设计和矫治技术的选择。材料方法 选择13例(男性1人,女性12人)12～45岁前牙开(牙合)畸形患者,对矫治设计和矫治技术进行总结分析,并对矫治前后的头颅侧位片进行测量分析,比较使用不同方法矫治前后的变化。结果 所有病例治疗后均取得满意疗效。其中1例为不拔牙矫治,4例为拔除第二或第三磨牙,8例为拔除双尖牙。不拔牙或拔除后牙矫治患者均采用MEAW矫治技术,通过直立磨牙、伸长切牙来改变平面、关闭开;拔除双尖牙患者采用滑动矫治技术通过内收前牙、前移磨牙来矫治开。结论 在正确诊断的前提下,结合病因治疗、选择适当的矫治技术是正畸治疗前牙开畸形成功的关键。     

Treatment results and long-term stability of anterior open bite malocclusion

OBJECTIVES: To evaluate treatment results and long-term stability of anterior open bite malocclusion and to identify predictive factors for both treatment results and their stability. DESIGN: Retrospective study. SETTING AND SAMPLE POPULATION: The Department of Orthodontics and Oral Biology at the Radboud University Nijmegen Medical Centre, The Netherlands. Fifty-two patients with an anterior open bite. METHODS: Lateral cephalograms and dental casts were analysed at: start of treatment (Ts), end of treatment (T0), 2 and at least 5 years after the end of treatment (T2 and T5, respectively). A standard cephalometric analysis was performed, while the Peer Assessment Rating (PAR) index was used to evaluate the occlusion. RESULTS: The mean PAR reduction at T0 was 74%, but decreased to 56% at T5. The mean overbite (OB) increased from -3.2 mm (+/- 1.9) at Ts to 0.4 mm (+/- 1.1) at T0, 0.1 mm (+/- 1.6) at T2 and 0.2 mm (+/- 1.8) at T5. Thirty-seven patients (71%) had a positive OB at T0, but the bite opened again in 10 of these patients (27%) from T0 to T5. Forty-four per cent of our patients had an open bite at T5. No pre-treatment variables could predict these changes. CONCLUSION: Treatment response and long-term stability of the anterior open bite was found to be rather poor. This has to be taken into consideration when planning treatment of open bite patients. Prediction of open bite closure at the end of active treatment or at the follow-up was not possible.     

Influence of rapid maxillary expansion in the stability of anterior open bite treatment

Clinical Oral Investigations - This study aimed to compare the stability of anterior open bite (AOB) in patients treated with and without rapid maxillary expansion (RME) before fixed palatal crib...     

Cephalometric evaluation of the anterior open bite treatment

The present study was aimed at evaluating the treatment changes of anterior open bite malocclusion cases treated by means of the Multiloop Edgewise Arch Wire technique, which is considered one of the more effective treatment modalities for anterior open bite malocclusions. The open bite sample was composed of 16 young adults, 4 males and 12 females. The normal occlusion sample, as a controlled sample was composed of 58 young adults who had pleasing facial profiles and normal occlusions with no experience of orthodontic or prosthodontic treatment. The normal sample was subdivided by the cephalometric vertical facial relationships. Forty adults with cephalometric vertical facial relationships within the normal range of Korean standards were classified as Normal Occlusion Group 1. Eighteen adults with an increased vertical facial relationship but with normal occlusion, were classified as Normal Occlusion Group 2. Thirty-nine reference points were digitized on each film, and the computerized cephalometric analysis was obtained with 8 skeletal, 10 dentoalveolar, 17 teeth angulations, and 4 occlusal plane measurements. Treatment changes were determined by the paired t test, and the structural differences between the four groups were tabulated by the Student’s t test. The treatment changes were observed mainly in the dentoalveolar region in the upper and the lower occlusal planes, accompanied by the uprighting of the posterior teeth to the occlusal plane through the distal tipping movement of the entire dentition. After the treatment, there was a tendency for the structural feature of the open bite group to approximate those of the normal occlusion group 2. This ascertains that the treatment changes of open bite malocclusion produced by means of the multiloop edgewise arch wire technique are similar to those found in the natural dentoalveolar compensatory mechanism. (Am J Orthod Dentofacial Orthop 1999;115:29-38)     

Relapse following surgical treatment of anterior open bite

From a series of 40 cases of anterior open bite treated surgically by Le Fort I osteotomy, four cases relapsed. The nature of the relapse was investigated by computer aided analysis of lateral cephalometric radiographs. The location, aetiology and possible prevention of the relapse is discussed for each case.     

Tongue muscle activity after orthodontic treatment of anterior open bite: A case report

A case report of a Class I malocclusion with an anterior open bite and bimaxillary dental protrusion was presented. The patient had a tongue thrust swallow and slight lisping. After the treatment, significant adaptation in electromyographic pattern of genioglossus muscle activity during swallowing was determined. However, remarkable change in the electromyographic pattern of the genioglossus muscle did not occur during chewing.     

A retrospective study of dento-alveolar injuries

Abstract Traumatic injuries to primary and permanent dentition may lead to severe therapeutic problems. The purpose of the investigation was to evaluate epidemiologic data of dentoalveolar injuries collected in a university dental clinic. The sample consisted of 300 patients (198 boys, 102 girls) representing 480 injured teeth, mostly maxillary incisors (94.6%). The results pointed-out a high predominance of traumatized primary teeth. Types of injuries differed between deciduous and permanent dentition: luxation injuries were most often recorded in primary dentition (81%), while a high percentage of crown and crown-root fractures were recorded in permanent dentition (38%). Epidemiological observations concerning location, etiology and distribution of dento-alveolar injuries are briefly discussed.