Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Open Bite”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,099 records · Page 61Linked to original sources

Tooth size-arch length relationships in the deciduous dentition: a comparison between contemporary and historical samples.

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.

Cephalometry↗

A dental Class III malocclusion treated to a full-cusp Class II molar relationship.

A case report of a Class III dental malocclusion superimposed on a straight skeletal pattern is presented. The patient was a 14-year-old girl with limited growth potential. This case included congenitally missing maxillary permanent lateral incisors, impacted maxillary permanent canines, and bilateral posterior open bites. The patient's soft-tissue profile was normally convex. In addition to her malocclusion, the patient had a history of difficulty breathing through the nose. The general treatment included palatal expansion, protraction headgear, and comprehensive edgewise orthodontic therapy.

Adolescent↗

Biomechanical basis of vertical dimension control during rapid palatal expansion therapy.

Rapid palatal expansion (RPE) is recognized as a very successful orthopedic therapy to correct maxillary transverse deficiencies in growing patients. However, the transverse forces delivered during RPE have been shown to create undesirable orthodontic and orthopedic side effects in patients exhibiting skeletal open bite tendency, large interlabial gap, or severe Class II skeletal patterns, with long lower facial height and increased facial convexity. The application of extraoral forces during RPE therapy by the concomitant use of a high-pull chincap is described and clinically illustrated as a method to control the vertical dimension.

Biomechanical Phenomena↗

Employing Tip-Edge brackets on canines to simplify straight-wire mechanics.

The straight-wire appliance was developed in part to reduce wire bending and therefore make treatment results more predictable. Because tip prescription is built into the bracket slots, teeth are held at their final crown angulations throughout treatment. Straight-wire brackets are used in an attempt to produce bodily tooth movement. However, teeth tend to tip when a force is applied. This tipping, especially when canines are retracted, can deflect the arch wire causing supereruption of the incisors with a resultant increase in anterior overbite and an open bite in the canine/premolar area. Placing Tip-Edge brackets (TP Orthodontics, Inc., LaPorte, Ind.) on canines and employing tipping and uprighting mechanics on these teeth can overcome these problems. Two cases are presented to illustrate this approach to treatment.

Adolescent↗

Cephalometric and computed tomographic predictors of obstructive sleep apnea severity.

The interaction between craniofacial structure assessed by lateral cephalometry, and tongue, soft palate, and upper airway size determined from computed tomography (CT) scans was examined in 25 control subjects and 80 patients with obstructive sleep apnea (OSA). On the basis of the cephalometric analyses, the patients with OSA had retruded mandibles with larger ANB angle differences, elongated maxillary and mandibular incisors and mandibular molars, and high total upper and lower face heights The computed tomographic evaluations revealed that patients with OSA also had larger tongue, soft palate, and upper airway volumes. Men with OSA and skeletal Class I malocclusions had significantly larger soft palates than comparable controls. Both tongue and soft palate volumes were positively correlated with body mass index. A principal component analysis reduced the database, and one significant correlation was identified. Subjects with high total, upper and lower face heights, elongated maxillary and mandibular teeth, and proclined lower incisors were observed to have large tongue, soft palate, and upper airway volumes, to have a higher apnea index and to be obese. Linear regression analysis indicated that a high apnea index was seen in association with large tongue and soft palate volumes, a retrognathic mandible, an anteroposterior discrepancy between the maxilla and mandible, an open bite tendency between the incisors, and obesity.

Adult↗

Associations between changes in selected facial dimensions and the outcome of orthodontic treatment.

The purpose of this study was to determine, in children with Class II, Division I malocclusion who were treated with functional appliances, the strength of the associations between the changes over 18 months in selected facial dimensions and the success of orthodontic treatment as determined by the weighted Peer Assessment Rating (PAR). Forty-two children, between 10 and 13 years of age (mean age 11.6 years), were randomly assigned to either an untreated group (control) or a group treated with either a Fränkel function regulator or Harvold activator (treatment). The outcome of treatment was assessed on study models and the craniofacial changes were measured on lateral cephalometric radiographs. Correlation coefficients were then calculated between the differences in the cephalometric variables over 18 months and the differences in the PAR scores. In the treatment group, the effects of normal growth were held constant by partial correlation. The partial used was the change in both stature and weight. Significant positive partial correlations were found between the increases in total anterior face height, posterior face height, S-Pg, and treatment success. Significant negative partial correlations were found between downward movement of the maxilla and mandibular body and lower anterior face height and treatment success. It is postulated that these associations occurred mainly in response to the bite opening by the appliances. Treatment success was also significantly associated with maxillary restriction, an increase in the SNB angle and a reduction in the ANB angle. Changes in B point due to proclination of the mandibular incisors were considered to be responsible for the two latter significant associations. Although mandibular length increased significantly in the treatment group, as compared with the control group, it was not significantly associated with treatment success.

Activator Appliances↗

Idiopathic condylar resorption: diagnosis, treatment protocol, and outcomes.

Idiopathic condylar resorption is a poorly understood progressive disease that affects the TMJ and that can result in malocclusion, facial disfigurement, TMJ dysfunction, and pain. This article presents the diagnostic criteria for idiopathic condylar resorption and a new treatment protocol for management of this pathologic condition. Idiopathic condylar resorption most often occurs in teenage girls but can occur at any age, although rarely over the age of 40 years. These patients have a common facial morphology including: (1) high occlusal and mandibular plane angles, (2) progressively retruding mandible, and (3) Class II occlusion with or without open bite. Imaging usually demonstrates small resorbing condyles and TMJ articular disk dislocations. A specific treatment protocol has been developed to treat this condition that includes: (1) removal of hyperplastic synovial and bilaminar tissue; (2) disk repositioning and ligament repair; and (3) indicated orthognathic surgery to correct the functional and esthetic facial deformity. Patients with this condition respond well to the treatment protocol presented herein with elimination of the disease process. Two cases are presented to demonstrate this treatment protocol and outcomes that can be achieved. Idiopathic condylar resorption is a progressive disease that can be eliminated with the appropriate treatment protocol.

Adolescent↗

Class II malocclusion correction: an American board of orthodontics case.

A Class II open bite malocclusion with a narrowed maxilla, an increased lower anterior facial height, and a tooth size discrepancy are presented. The malocclusion was treated nonextraction in 2 phases. The mixed dentition phase of treatment was maxillary molar uprighting followed by a bonded rapid palatal expander. The vertical dimension was managed with a vertical pull chincup. The full appliance phase included buildups of the maxillary lateral incisors and mechanics to control lower incisor position.

Cephalometry↗

Effects of mandibular incisor extraction on anterior occlusion in adults with Class III malocclusion and reduced overbite.

The aim of this study was to assess the treatment outcome and changes in mandibular incisor position after extraction of one single incisor in 36 adult orthodontic cases with combined Class III and open bite tendencies. The cases consisted of 21 female and 15 male patients with an average age of 27.8 years (standard deviation [SD], 11.1 years) at the start. Fixed 0.018-inch Edgewise appliances were used in both arches in 19 patients and in the mandibular arch in 17 patients. Average treatment time was 18 months (SD, 7.1 months). Pretreatment ANB was 0.5(o) (SD, 2.7 degrees), overjet 1.4 mm (SD, 1.9 mm), and overbite 1.5 mm (SD, 1.1 mm). The lower incisors were 3.6 mm (SD, 2.8 mm) in front of the APg-line, and the Averaged Irregularity Index was 1.1 mm (SD, 0.6 mm). Records representing pretreatment (T1), posttreatment (T2), and average 4.3 years (SD, 2.3 years) retention (T3) included cephalograms, panoramic films, intraoral and extraoral photographs, and plaster models. All cast measurements were made with digital calipers. On the cephalograms, the lower incisor tips moved posteriorly 1.7 mm (SD, 2.0 mm) and occlusally 1.5 mm (SD, 1.8 mm) from pretreatment to posttreatment. Relative to the x-axis, they tipped lingually 5.9(o) (SD, 5.6 degrees). On the cast analysis, overjet increased 1.0 mm (SD, 1.9 mm) and 1.5 mm (SD, 1.5 mm) for the maxillary central and lateral incisors, respectively, whereas overbite increased 0.6 mm for both the central and lateral incisors. The intercanine width was reduced by 3.3 mm (SD, 2.0 mm), while the intermolar width was unchanged. The Average Irregularity Index was reduced from 1.1 to 0. 2 mm. Arch-length was reduced 3.6 mm from pretreatment to posttreatment, and another 0.3 mm from posttreatment to 4.3-years retention. Other changes from posttreatment to 4.3-years retention were slight. No loss of the interdental gingival papillae was normally observed. It is concluded that the extraction of one mandibular incisor can lead to satisfactory treatment results in adults with mild Class III malocclusion and reduced overbite, particularly when coupled with a large mandibular intercanine width and minor crowding, and some mandibular tooth size excess. However, the orthodontic treatment frequently became more complicated and time-consuming than expected at the start.

Adult↗

Class II, division 1, case with multiple treatment challenges.

This is a case report of a 23-year-old black woman with a skeletal Class II Division 1 malocclusion and an anterior open bite. The maxillary central incisor root was severely dilacerated, a maxillary lateral incisor and canine were transposed, a maxillary canine was impacted near the orbital rim, and a mandibular second premolar was congenitally missing. Selective extractions and attention to detail provided outstanding occlusal function and improved facial esthetics.

Adult↗

Stability after vertical subcondylar ramus osteotomy for correction of mandibular prognathism.

A cephalometric analysis of the positional changes of the mandible and the upper and lower incisors following vertical subcondylar ramus osteotomy was performed on 80 patients. The patients were prognathic without laterognathism or open bite and all the patients had preoperative orthodontic treatment. 40 patients were operated with an intraoral (IVSO) and 40 with an extraoral approach (EVSO). Both groups showed postoperatively posterior rotation of the mandible, shortening of the posterior facial height, increase in anterior facial height and extrusion of the incisors in both jaws. A significantly greater reduction of posterior facial height was observed in the EVSO-group, but otherwise the 2 groups did not reveal any statistically significant positional differences. The material was sub-divided into 2 groups 1 with (n = 32) and one group without (n = 48) extra skeletal (nasomandibular) fixation in addition to the intermaxillary fixation. Significantly less positional changes of the incisors and less increase of anterior facial height was found in the group with skeletal fixation, but the influence on other skeletal alterations was limited. After release of the intermaxillary fixation, the only difference between the groups was intrusion of the earlier extruded incisors, most pronounced in the group without skeletal fixation.

Adolescent↗

Changes in the temporomandibular joint caused by the vertical facial pattern. Study on an experimental model.

An experimental model reproducing open bite or verticalized facial pattern was used to study its effect on the temporomandibular joints. 140 Wistar rats were used, divided into 3 groups: bilateral resection of the masseteric muscle, simulated muscular resection and control group. A series of radiological, morphological and histological tests were analyzed. The posterior rotation of the jaw caused by muscular resection although not producing a degenerative effect, did produce specific articular changes in the temporomandibular joint components.

Animals↗

Extraoral subcondylar ramus osteotomy for correction of mandibular prognathism. The surgical technique and complications.

1178 patients with mandibular prognathism and/or asymmetry, in some cases combined with maxillary retrognathism, were treated by extraoral horizontal or oblique ramus osteotomy during the period from 1939 to 1989. The described percutaneous retromandibular approach is a simple, rapid and reliable technique which can usually be performed under local anaesthesia. Very few complications, particularly neurological, were observed. These aspects justify consideration of this technique when indications for a simple, straight set-back procedure of the mandible exist, and there is no tendency to bite-opening. However, the method demands intermaxillary fixation for 6-9 weeks postoperatively.

Adolescent↗

Cutaneous manifestation of sarcoidosis (Boeck) with severe osseous destruction of the midface. A case report.

A 16-year-old Caucasian girl presented with brownish red plaques and papules beneath the right eye, and a right side open bite. The cutaneous changes had occurred more than 13 years previously. Radiological evaluation of the chest demonstrated bilateral hilar lymphadenopathy. Kveim-Siltzbach test of the skin was positive. Histological examination of several biopsy specimens taken from skin, oral mucosa and anterior wall of the right paranasal sinus revealed the diagnosis of sarcoidosis (Boeck). Therefore steroid therapy was initiated and the patient was placed on 40 mg prednisone daily. Under this treatment the sarcoidosis manifestations improved generally, and the prednisone dose was subsequently reduced.

Adolescent↗

Mandibular autorotation in orthognathic surgery: a new method of locating the centre of mandibular rotation and determining its consequence in orthognathic surgery.

Rotation of the mandible is simulated through the centre of the condyle in planning orthognathic surgery. Previous studies have suggested that the initial mandibular movement is better characterized as multiple parts of the segments of a circle with the average centre located below and behind the centre of the condyle. This paper describes a method of locating the centre of mandibular rotation by computer-analysis of two lateral cephalograms with different degrees of opening. The method was used on 10 normal individuals showing an average centre of mandibular rotation 14.9 mm below and 5.0 mm behind the superior midsurface of the condyle for movements from occlusion to an opening of 10 mm. The implications of the located centre of rotation on orthognathic surgery was determined by simulating a closure of a 9.5 mm open bite. An error of up to 9.3 mm in the horizontal position of the maxilla would occur if the centre of the condyle was used. A retrospective study on 10 patients with increased anterior facial height was undertaken and a mean centre of rotation 8.4 mm behind and 25.1 mm below the centre of the condyle was found. Simulating the rotation of the mandible through the centre of the condyle would have resulted in a difference between the predicted and actual horizontal position of the maxilla ranging from 0.4-10.4 mm. It was concluded that using the centre of the condyle as the centre of mandibular rotation in the planning of superior maxillary movement with a Le Fort I osteotomy may cause considerable error in the horizontal position of the maxilla in most cases.

Cephalometry↗

Postero-lateral expansion osteotomy of maxilla. A case report.

The posterior-maxillary osteotomy introduced by Schuchardt was designed to close skeletal anterior open bite. Also, it can be used to reduce a posterior cross bite. But in this latter case, the most important problem is the difficulty in expanding the maxilla because of the relative inelasticity of the palatal mucosa. This paper reports on the result obtained by a surgical expansion technique without orthodontic treatment. The use of a local soft tissue flap is necessary; the anteroposterior part of the palatal incision is placed contralaterally to the bone incision. A palatal appliance is used for the retention of the palatal flap.

Adult↗

Analysis of primary gingivoperiosteoplasty in alveolar cleft repair. Part I: Facial growth.

The primary gingivoperiosteoplasty by Millard consists of presurgical active orthognathic treatment ('Latham device') of the alveolar margins at the age of 3 months and of surgical closure of the alveolar cleft with local gingivoperiosteal flaps at the age of 5 months. The aim of this investigation was to analyse the facial growth following this treatment. The following material was studied: lateral head X-rays and plaster casts from 146 patients with unilateral (UCLP) and bilateral (BCLP) clefts of lip and palate from birth to 16 years of age. Ninety-one of these patients formed the control group, who received neither gingivoperiosteoplasty nor pre-surgical active orthognathic treatment. The same surgeon and orthodontist treated all 146 patients. A three-dimensional growth disturbance after gingivoperiosteoplasty was observed: 42% patients with UCLP and 40% patients with BCLP had an 'open bite' following closure of the alveolar cleft (control group 5%/10%). The length of the upper jaw in patients who underwent gingivoperiosteoplasty was shorter than in the control group. The frequency of posterior cross bite was also higher in the gingivoperiosteoplasty group. These results demonstrate that treatment with a 'Latham device' disturbs facial growth. Therefore, this treatment should be abandoned.

Adolescent↗