• The korean journal of orthodontics
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• v.25 no.5 s.52
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• pp.641-654
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• 1995

The purpose of this report is to present the cause and treatment of posterior open bite. Posterior open bite is the open bite limited to posterior teeth. These problem usually are attributed to a mechanical interference with the eruption process, either ankylosis or some soft tissue interference. But, in some patient, lateral open bite is due to a disturbance of the eruptive mechanism itself and other disease or side effect following other treatment. Distinguising cause of posterior open bite, lack of eruption due to some external interference with eruption or primary failure of eruption mechanism, is important clinically because this determines the prognosis for orthodontic treatments. The characteristics, differential diagnosis with posterior open bite due to other etiologies and the treatment of these problems are presented and discussed,.

• The korean journal of orthodontics
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• v.23 no.3 s.42
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• pp.391-403
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• 1993

For the purpose of investigating mesiodistal axial inclination of posterior teeth in normal occlusion group, open bite and deep bite group and investigating the correlationship between the axial inclination of posterior teeth and overbite of anterior teeth, a cephalometric study was performed on the subjects consisted of normal occlusion group(40), open bite group(71 : Angle's Class I, Class II, division 1 25, Class III 25) and deep bite group(64 : Angle's Class I 23, Class II, division 1 21, Class III 20). Mesiodistal axial inclination of posterior teeth to occlusal, mandibular and palatal plane were measured. The findings of this study were as follows : 1. Upper and lower posterior teeth were more mesially inclined to occlusal plane in open bite group than in deep bite group. 2. Lower posterior teeth were more mesially inclined in deep bite group than in open bite group in Angle's Class II, division 1 malocclusion but there were no significant differences in Angle's Class I and Class III malocclusion. 3. There was no significant correlationship between the axial inclination of posterior teeth to each plane and overbite of anterior teeth in open bite group. 4. There was a significant correlationship between the axial inclination of upeer and lower second premolar to occlusal plane and overbite of anterior teeth in Angle's Class I, Class II, division 1 and Class III malocclusion.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.20.1-20.7
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• 2020

Background: Anterior open bite is a challenging malocclusion to correct orthodontic treatment. Anterior open bite associated with over-erupted posterior teeth and long lower facial height should be treated by reduction of posterior dimension for esthetic results. Although the possibility of orthodontic treatment of an anterior open bite has increased with the introduction of skeletal anchorage, there are still cases requiring surgery for various reasons. Case presentation: This case report covers an anterior open bite of a 25-year-old man successfully treated with the posterior maxillary segmental osteotomy (PMSO) and miniplates. After the pre-surgical orthodontic treatment, the PMSO between canines and first premolars was performed under local anesthesia and miniplates were placed on the zygomatic buttress. As a result of 28 months of treatment, an impaction amount of 3.5 mm was obtained in the maxillary posterior teeth, and the facial esthetics improved at rest and smile. Conclusion: The impaction of the posterior dentoalveolar segment using the PMSO can be a good treatment option in patients with anterior open bite showing long lower facial height.

• The korean journal of orthodontics
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• v.11 no.2
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• pp.109-123
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• 1981

The author studied and analyzed statistically 112 adults female ranging in age from 18 to 20 years with normal occlusion, 56 adults female ranging in age from 18 to 24 years with deep overbite and 53 adults female ranging in age from 18 to 28 years with open bite by vertical cephalometric analysis. The results were as follows; 1. In comparing normal occlusion with deep overbite and open bite, skeletal linear measurements were more significant than dentoalveolar linear measurements. SN-MP angle, SN-OP angle, PP-OP angle and Xi angle (ANS-Xi-Pog) were significant in anglular measurements. 2. Upper posterior facial height (SE-PNS), upper anterior alveolar height, lower posterior alveolar height, lower posterior alveolar height/lower anterior alveolar height and SN-PP angle were non significant between deep overbite and open bite. 3 The most significant items between deep overbite and open bite were lower anterior facial height (ANS-ME) and SN-MP angle. 4. Correlation coefficients of angular measurements were higher in deep overbite, while that of linear measurement total anterior facial height (N-ME) was higher in open bite. 5. In the multiple regression equation, significant variables were total anterior facial height (N-ME), lower anterior alveolar height, upper anterior alveolar height, upper posterior alveolar height, Xi angle (ANS-Xi-Pog) and ramus height (AR-Go) in deep overbite, and total anterior facial height (N-Me), lower anterior alveolar height, ramus height (AR-Go), lower posterior alveolar height, PP-MP angle and upper posterior facial height (SE-PNS) in open bite.

• The korean journal of orthodontics
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• v.39 no.6
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• pp.402-419
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• 2009

Successful treatment of the non-growing patient with an open bite of either dental skeletal pattern often presents a difficult challenge. The morphologic pattern in anterior open bite is characterized by longer vertical dimensions, an increase in development of the maxillary posterior dento-alveolar structure and a steep mandibular plane. In such cases, molar intrusion would be a good remedy for treatment. This article reports the successful treatment and retention of two anterior open-bite cases. We used orthodontic mini-implants for treatment and a circumferential retainer with posterior bite block or skeletal fixed retainer for retention. The diagnostic criteria and mechanics for appropriate treatment are discussed. Our results suggest that open bite can be reduced successfully with intrusion of molars using orthodontic mini-implants (OMI) without orthognathic surgery, and that circumferential retainer with posterior bite block and skeletal fixed retainer are effective for retention.

• The korean journal of orthodontics
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• v.9 no.1
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• pp.133-140
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• 1979

The author compared patients showing two extremes of incisor vertical relationship to find out differences in craniofacial morphology which might influence face height and incisor overbite. The subjects consisted of 53 open-bite cases and the same number of deep-bite cases. The results were as follows: 1. On the average, the lower face height was significantly greater in open-bite cases than in deep-bite cases. 2. In open-bite cases, gonin-menton length was significantly greater than in deep-bite cases. In deep-bite cases, anterior cranial base length and posterior cranial base length were significantly greater in open-bite cases. 3. The jaw angle was significantly greater in open-bite cases. 4. The gonion-menton-nasion angle was significantly greater in deep-bite cases. 5. From geometric standpoint, the increase of jaw and joint angle would increase lower face height, but these two showed negative correlation. 6. The sizes of the jaw and joint angle might be factors of open-bite or deep-bite, but these were not the only variables that determined lower face height. 7. In open-bite cases, there was a closer correlationship between lower face height and the other linear measurments than in deep-bite cases. In deep-bite cases, there was a closer correlationship between lower face height and the other angular measurements than in open-bite cases. 8. Considering both linear and angular measurements of facial polygon, all contributed significantly to the lower face height. The nonsignificant variables were jaw and joint angle in open-bite cases, and anterior cranial base length, jaw angle, and joint angle in deep-bite cases.

• Imaging Science in Dentistry
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• v.47 no.3
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• pp.157-164
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• 2017

Purpose: This study determined and compared the distances from the maxillary root apices of posterior teeth to the floor of the maxillary sinus, or maxillary sinus distances(MSDs), and the distances from the mandibular root apices of the posterior teeth to the mandibular canal, or mandibular canal distances(MCDs), in Thai subjects with skeletal open bite and skeletal normal bite. Materials and Methods: Pretreatment cone-beam computed tomography (CBCT) images were obtained from 30 Thai orthodontic patients (15 patients with skeletal normal bite and 15 with skeletal open bite) whose ages ranged from 14 to 28 years. The CBCT images of the patients were processed and measured using the Romexis Viewer program. The MSDs and MCDs from the root apices of the maxillary and mandibular second premolar, first molar, and second molar to the maxillary sinus floor or the mandibular canal were measured perpendicularly to the occlusal plane. The Student t test was used for comparisons between the 2 groups. Results: The greatest mean MSDs were from the root apex of the second premolars in both groups, whereas the least mean MSDs were from the mesiobuccal root apex of the second molars. The greatest mean MCDs were from the mesial root apex of the first molars, whereas the least mean MCDs were from the distal root apex of the second molars. Conclusion: There were no differences in the mean MSDs or the mean MCDs between the skeletal normal bite group and the skeletal open bite group.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.455-474
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• 1993

Degenerative joint disease(DJD) has hun known as one of the diseases which affect the middleor old-aged people. But as orthodontists are getting interested in the adult orthodontics, it is not rare for them to meet the open-bite patients with the TMJ DJD in their clinics. The purpose of this article is to investigate the cephalometric characteristics of the open-bite cases with TMJ DJD. Twelve TMJ DJD patients($15.1\~39.5$ years old) were selected from the patients who visited Department of Orthodontics, Seoul National University Hospital. Cephalograms were taken and means from 60 measurements were compared by t-test with those of the fifty four healthy adults($20.0\~26.7$ years old) who have normal occlusion and TMJ. In this study male and female are compared respectively, for in the normal samples 26 measurements showed significant differences between the male and the female. The results and conclusions axe as follows: 1 In DJD group, ANB and Angle of convexity decreased, which means the retruding of the mandible. The interincisal angle was smaller than that of the normal group. The means of the overbite were -2.1mm in male and -3.0mm in female, and the means of the overjet were 5.6mm in male and 6.7mm in female. The profile was similar to that of Angle's Class II div.1 open-bite. 2. SN-GoMe and FMA increased in DJD but SN-PP and FH-PP did not show any significant difference. In TMJ DJD open-bite cases, the bony structure lower than the palatal plane seemed to play an important role in developing open-bite. 3. In DJD group, PH-ArGo, SArGo and Y-sxis angle increased significantly, but genial angle showed no significant difference. The means of hか were 50.1mm in male and 40.2mm in female, which were significantly smaller than those of the normal(56.5mm in male, 50.9mm in female). These findings seemed to indicate the posterior rotation of mandible resulted from the shortening of the ramus height. 4. Anterior faical height(AFH), upper anterior facial height(UAFH) and lower anterior facial height (LAEH) of DJD showed no significant increase as compared with those of the noraml group. There was no significant difference in the ratio of upper anterior facial height to lower anterior facial height(UAFH/LAFH). But, lower posterior facial height(LPFH) was significantly smaller than that of the normal group. 5. It was thought that the peculiar profile of the TMJ DJD open-bite was resulted from the posterior rotation of mandible as the ramus became short following the degerative destruction of of the condylar head and neck.

• The korean journal of orthodontics
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• v.45 no.1
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• pp.38-46
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• 2015

Objective: This prospective clinical study aims to determine the differences between two treatment modalities for anterior open bite in growing patients. The treatment modalities involved the use of magnetic bite-blocks (MBBs) or rapid molar intruders (RMIs) applied with posterior bite-blocks. Methods: Fifteen consecutive patients with a mean age of 11.2 (standard deviation [SD] = 1.6) years and a mean open bite of -3.9 mm were treated with MBBs. Another 15 consecutive patients with a mean age of 10.9 (SD = 1.8) years and a mean open bite of -3.8 mm were treated with RMIs applied on bite-blocks. Cephalometric radiographs were obtained before (T1) and immediately after appliance removal (T2). The treatments lasted four months, during which the appliances were cemented to the teeth. The morphological changes were measured in each group and compared using logistic regression analysis. Results: The MBB group exhibited significantly greater decreases in SNA angle, ANB angle, overjet, and maxillary incisor angle (p < 0.05). The MBBs induced greater effects on the maxilla and maxillary dentition. The MBBs restrained maxillary forward growth and retracted the maxillary incisors more effectively than did the RMIs. Consequently, changes in the intermaxillary relationships and overjets were more distinct in the MBB group. Conclusions: The anteroposterior differences between the appliances suggest that MBBs should be preferred for the treatment of patients with Class II open bites and maxillary incisor protrusions.

• The korean journal of orthodontics
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• v.12 no.1
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• pp.37-43
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• 1982

The patient,20 year-old female, complained of anterior open bite. She had tongue thrusting habit and suffered from maxillary sinusitis since 12-years old. Cephalometric analysis revealed slightly forward relationship in maxilla, but normal in mandible. The anterior open bite was corrected through retraction and extrusion of anterior segment and mesial movement of posterior segment under multibanded system after extraction of 4-first premolars. After 2 years and 3 months, she gained ideal overbite, overjet and good interdigitation of buccal segment.