Bimaxillary Dentoalveolar Protrusion Research Articles

An Innovative Treatment Approach with Atypical Orthodontic Extraction Pattern in Bimaxillary Protrusion Case

This case report describes the treatment of a 23-year-old female with severe bimaxillary dentoalveolar protrusion and missing left mandibular first molar. Her chief concern was significant facial convexity. Generally treatment plan of such cases involves extraction of first premolars but absence of first molar complicates situation with problem of space management, anchorage requirement and post-treatment occlusion. This case report introduces thought provoking treatment approach of selecting atypical teeth for orthodontic extraction without compromising the quality of treatment outcomes. However, three first bicuspids were extracted while the mandibular left second premolar was distalized into the missing molar space and used as an abutment for replacement of the missing first molar by prosthesis. Despite the unusual asymmetric extraction of teeth, superimposition of the pretreatment and post-treatment cephalometric tracings shows excellent treatment outcomes and reduction of facial convexity by maximum retraction of the anterior teeth.

Vertical changes during Begg’s and PEA-A Comparative Study

The purpose of this study was to compare the vertical dimensional changes in bialveolar dental protrusion patients undergoing extraction of all four first premolars between the preadjusted edgewise appliance(PEA)(MBT) and the Begg appliance. The cephalometric records of 40 patients with Class I bimaxillary protrusion were selected and devided in two groups i.e Begg or PEA mechanotherapy. The age group of 18-25 years was selected for both groups. Skeletal and dental changes were analysed in both groups on lateral cephalograms taken pre (T1)& post (T2) treatment. A student t-test was used to analyse the treatment changes. Significant increase in face height and extrusion & mesial movement of lower molars within both groups were found. However no significant difference was found when the Begg mechano-therapy was compared to PEA Technique on vertical dimensional changes. I. Introduction Extraction of teeth has always been the primary method of gaining space for either correction of severe crowding or retraction of proclined teeth. It also helps in closing the bite in open bite subjects and has therefore been suggested as a method of controlling the vertical dimension of the face. The vertical dimension of the face increased following orthodontic treatment as the molars were extruded because of inter-arch mechanics, which consequently caused clockwise rotation of the mandible. Further fuelling this controversy, Cusimano and McLaughlin (1993) and Upadhyay et al. (2008) suggested that occlusal movement of the posterior teeth tends to keep pace with the increase in anterior face height, thus maintaining the mandibular plane angle and nullifying any bite-closing effect of protraction of the posterior teeth. Swain and Ackerman (1969) and Williams (1977) reported considerable molar extrusion under the influence of Class II elastics. However, James (1968) and Thompson (1972) found that with the Begg appliance, the deep bite was corrected primarily by simultaneous extrusion of the mandibular molars and intrusion of the lower incisors. It was suggested that molar extrusion might lead to a backward rotation of the mandible increasing the vertical facial dimension with a potentially detrimental effect on facial aesthetics. The aim of this research was to evaluate and compare the changes in the vertical facial dimension in Angle Class I bimaxillary dentoalveolar protrusion subjects on an underlying Class I or mild Class II skeletal base treated with first four premolar extractions with the Begg or PEA(MBT) technique.

Severe bimaxillary dento-alveolar protrusion with dental anterior open bite treated with absolute anchorage – a case report

This article describes the orthodontic treatment of an 18-year-old boy with severe bimaxillary dento-alveolar protrusion and an anterior open bite. Orthodontic mini-implants were placed in the alveolar bone in all the four quadrants to provide anchorage for en masse retraction. The patient had an anterior tongue thrust with an anterior open bite. Successful dental retraction was achieved, along with closure of the anterior open bite. Facial aesthetics were improved for the patient, fullness of the upper and lower lips was reduced, and the interdental relationship was corrected. Clinical Relevance: To describe the use of mini-implants to provide anchorage in a case of severe bimaxillary dento-alveolar protrusion.

Adjunctive Treatment of Gummy Smile Using Botulinum Toxin Type-A (Case Report)

A 13 Year old female came for a consultation with chief complaints of protrusive lips and a gummy smile. The clinical examination showed a convex profile, a retrognathic mandible, excessively proclined and extruded maxillary incisors, and skeletal class II malocclusion with bimaxillary dento alveolar protrusion. Treatment was started using conventional mechanics for intrusion and retraction of upper anterior teeth, thereby improving soft tissue profile and correction of gummy smile. But only orthodontic treatment was not enough for correction of excessive gingival display during smile secondary to hyperactive upper labial muscle activity. Thus injection of Botulinum toxin type-A was given to correct gummy smile as an adjunctive treatment. Excellent correction of gummy smile following 2 weeks of Botox injection was achieved without any side effects. The patient received a satisfactory occlusion and an attractive smile.

Three-dimensional evaluation of upper anterior alveolar bone dehiscence after incisor retraction and intrusion in adult patients with bimaxillary protrusion malocclusion

The purpose of this study was to evaluate three-dimensional (3D) dehiscence of upper anterior alveolar bone during incisor retraction and intrusion in adult patients with maximum anchorage. Twenty adult patients with bimaxillary dentoalveolar protrusion had the four first premolars extracted. Miniscrews were placed to provide maximum anchorage for upper incisor retraction and intrusion. A computed tomography (CT) scan was performed after placement of the miniscrews and treatment. The 3D reconstructions of pre- and post-CT data were used to assess the dehiscence of upper anterior alveolar bone. The amounts of upper incisor retraction at the edge and apex were (7.64±1.68) and (3.91±2.10) mm, respectively, and (1.34±0.74) mm of upper central incisor intrusion. Upper alveolar bone height losses at labial alveolar ridge crest (LAC) and palatal alveolar ridge crest (PAC) were 0.543 and 2.612 mm, respectively, and the percentages were (6.49±3.54)% and (27.42±9.77)%, respectively. The shape deformations of LAC-labial cortex bending point (LBP) and PAC-palatal cortex bending point (PBP) were (15.37±5.20)° and (6.43±3.27)°, respectively. Thus, for adult patients with bimaxillary protrusion, mechanobiological response of anterior alveolus should be taken into account during incisor retraction and intrusion. Pursuit of maximum anchorage might lead to upper anterior alveolar bone loss.

Morphological analysis of the skeletal remains of Japanese females from the Ikenohata-Shichikencho site

The aim of this study was to assess morphological differences between early-modern (Edo) Japanese and contemporary Japanese using recently uncovered human female remains at the Ikenohata-Shichikencho site in the Tokyo urban area. In this study, 30 female skeletal remains that still retained the upper and lower first molars and central incisors were selected [early-modern (Edo) Japanese group]. Forty contemporary female Japanese were selected as a control. Analyses by standard methods of geometric morphometrics revealed some morphological differences between the early-modern (Edo) Japanese group and the contemporary Japanese group. For example, the early-modern (Edo) Japanese group exhibited bimaxillary dentoalveolar protrusion, a flat occlusal plane, and a large S-N length. On the other hand, the contemporary Japanese group exhibited slight protrusion of the anterior nasal spine. These findings may be of interest to orthodontists who are studying age variation or temporal differences and could lead to a better understanding of morphological diversity and variability.

A comparative evaluation of rate of space closure after extraction using E-chain and stretched modules in bimaxillary dentoalveolar protrusion cases

Aim of this study was to compare the rate of space closure between E-chain mechanics in one side of upper arch and by elastomeric module with ligature wire on the contralateral side in same patient. Thirty bimaxillary dentoalveolar protrusion cases were taken up for comprehensive fixed orthodontic treatment after extraction of all first premolars to retract both upper and lower anterior teeth. After initial alignment and levelling, alginate impressions were made for upper and lower arches and models constructed. In the upper arch model a vernier caliper was used to measure the extraction space in both sides from middle point of distal surface of canine to the middle most point of mesial surface of second premolar. This is the amount of space present before the onset of retraction mechanics. During space closure procedure two different retracting components were applied in right and left sides of each case. On right side elastic chain (E-chain) applied in both upper and lower arches and on left side elastomeric module with steel ligature (0.010") stretched double its diameter fixed in both arches. Both the mechanisms produced approximately 250-300 g of force as measured by a tension gauge. After onset of retraction mechanism all patients were recalled after every six weeks for three visits. In all these three visits modules and E-chains were changed. In all three visits impression was made, models constructed, and the remaining available space was measured by a vernier caliper up to 0.1 mm level variations. Mean value for total space closure in case of E-chain was 2.777 mm whereas in case of module with ligature wire the value increased to 3.017 mm. Mean value for rate of space closure in case of E-chain was 0.2143 mm, whereas in case of module with ligature wire the value increased to 0.2343 mm with a standard deviation of 0.001104 and 0.001194, respectively. The standard deviation for total space closure was 0.1305 for E-chain and 0.1487 for module with ligature wire. Space closure by elastomeric module with ligature wire is better than the E-chain.

Facial profile preferences: Differences in the perception of children with and without orthodontic history

Improved facial esthetics can be fully achievable only if facial preferences of the treated group are known. We hypothesized that facial profile perception and preferences could be influenced by orthodontic treatment. Differences in facial profile preferences between children with and without an orthodontic history were investigated in a sample of 1626 children aged 12 to 19 years (mean age, 14.8 ± 2.2 years) from 24 public schools in Zagreb, Croatia, randomly selected by using a cluster sampling procedure. Eight profile distortions for each sex, morphed by a digital imaging technique, were used for estimation. Analysis of variance (ANOVA), Bonferroni, and 2 independent sample t tests were used to compare the preferences of the groups. A straight profile was the most favored in both sexes, regardless of previous orthodontic history. A bimaxillary alveolar protrusive profile with thicker lips was preferred among the female profiles, and a bimaxillary retrusive profile with flat lips and a prominent chin was preferred among the male profiles. Orthodontic history and personal facial profile had little effect, and sex had a slightly greater influence on personal facial profile preferences. It seems that orthodontic therapy has no clinically relevant influence on facial profile preferences. Depending on the patient's sex, orthodontists should have different criteria for treating borderline patients with bimaxillary dentoalveolar protrusion and mandibular prognathism.

The use of mini-implants in en masse retraction for the treatment of bimaxillary dentoalveolar protrusion

This case report describes the treatment of a 22-year-old girl who had incompetent lips with severe bimaxillary dentoalveolar protrusion. The treatment of choice for such patients is usually extraction of four first premolars and retraction of the anterior teeth. To maintain the extraction space, maximum anchorage is required. Mini-implants were used to provide maximum anchorage for obtaining a good facial profile.

Soft tissue changes associated with first premolar extractions in adult females

Abstract Background The potential for premolar extractions to produce changes in the soft tissue profile after orthodontic treatment is controversial. Aim To evaluate the soft tissue changes associated with four first premolar extractions in adult females of South Indian ethnicity. Method Pre- and post-treatment lateral cephalometric radiographs of 30 adult female patients of South Indian ethnicity with bimaxillary dentoalveolar protrusion, requiring premolar extractions as a part of their orthodontic treatment, were used. The radiographs were traced and changes in three angular and 12 linear measurements measured relative to the perpendicular to the horizontal reference line, 7 degrees down from S-N through S. Correlation coefficients between the changes in the upper and lower incisors and the lip measurements were calculated. Results All linear and angular measurements, except for changes in upper and lower lip thickness, B’ point and the anterior point on the lower lip, showed statistically significant (p < 0.05) changes with treatment. A significant negative correlation was found between upper incisor change and nasolabial angle change and a significant positive correlation was found between upper incisor change and retraction of the most anterior point on the upper lip. Conclusion Extraction of the four first premolars followed by the retraction of incisors reduced the dental and soft tissue protrusion found in adult South Indian females with bimaxillary dentoalveolar protrusion.

Three-dimensional dental model analysis of treatment outcomes for protrusive maxillary dentition: Comparison of headgear, miniscrew, and miniplate skeletal anchorage

The aim of this retrospective study on dental models was to compare the orthodontic outcomes of maxillary dentoalveolar protrusion treated with headgear, miniscrews, or miniplates for maximum anchorage. The 40 subjects were diagnosed as having either Angle Class II malocclusion or Class I bimaxillary dentoalveolar protrusion. All patients were treated to retract the maxillary dentoalveolar process by using the extraction space of the bilateral maxillary first premolars. They were divided into 3 groups according to the type of anchorage used. Group 1 (n = 16) received traditional anchorage preparation with a transpalatal arch and headgear, group 2 (n = 15) received miniscrews, and group 3 (n = 9) received miniplates for skeletal anchorage. To investigate the movement of the maxillary teeth during dentoalveolar retraction, we used a 3-dimensional (3D) digitizer to assess the positional changes of the maxillary teeth relative to the stable palatal rugose structures on the serial dental models. The 3D coordinates representing pretreatment and posttreatment maxillary dental casts were superimposed to determine the movement of individual teeth from the positional changes of 18 landmarks of the central incisor, canine, second premolar, and first molar. Three-dimensional analysis of the maxillary dental models in the buccopalatal, anteroposterior, and vertical directions showed significant differences in tooth movements between the headgear and the mini-implant (miniscrew or miniplate) groups. Both skeletal anchorage groups had greater incisor retraction (6.9 mm for the miniscrew, 7.3 mm for the miniplate) than did the headgear group (5.5 mm). Mesialization of occlusal centroid of the maxillary molar in the skeletal anchorage groups was less than that in the headgear group (1.3 mm for the miniscrew, 1.4 mm for the miniplate, 2.5 mm for the headgear). Tooth movements in the anteroposterior and buccopalatal directions did not reach a statistically significant difference between the miniscrew and miniplate groups, but the maxillary posterior teeth of the subjects receiving miniplates showed greater intrusion than those receiving miniscrews anchorage. This 3D analysis of serial dental models demonstrated that, compared with headgear, skeletal anchorage achieved better results in the treatment of maxillary dentoalveolar protrusion. Significant intrusion of the maxillary posterior teeth was noted in the miniplate group but not in the miniscrew and headgear groups. Greater retraction of the maxillary anterior teeth, less anchorage loss of the maxillary posterior teeth, and the possibility of maxillary molar intrusion all facilitated correction of the Class II malocclusion, especially for patients with a hyperdivergent face.

Comparison of treatment outcomes between skeletal anchorage and extraoral anchorage in adults with maxillary dentoalveolar protrusion

The goal of this retrospective cephalometric study was to compare orthodontic outcomes in patients with maxillary dentoalveolar protrusion malocclusion treated with extraoral headgear or mini-implants for maximum anchorage. Forty-seven subjects with Angle Class II malocclusion or Class I bimaxillary dentoalveolar protrusion were treated by retracting the maxillary dentoalveolar process by using the extraction space of the bilateral maxillary first premolars. Two anchorage systems were used. Group 1 (n = 22) received traditional anchorage preparation with a transpalatal arch and headgear; group 2 (n = 25) received mini-implants (miniplates, miniscrews, or microscrews) for bony anchorage. Pretreatment and posttreatment lateral cephalograms were superimposed to compare the following parameters between groups: (1) amount of maxillary central incisor retraction, (2) reduction in maxillary central incisor angulation, (3) anchorage loss of the maxillary first molar, (4) movements of the maxillary central incisor and first molar in the vertical direction, and (5) changes in skeletal measurements representing the anteroposterior and vertical jaw relationships. The skeletal anchorage group had greater anterior tooth retraction (8.17 vs 6.73 mm) and less maxillary molar mesialization (0.88 vs 2.07 mm) than did the headgear group, with a shorter treatment duration (29.81 vs 32.29 months). Translational movement of the incisors was more common than tipping movement, and intrusion of the maxillary dentition was greater, in patients receiving miniplates than in those receiving screw-type bony anchorage, resulting in counterclockwise rotation of the mandible and a statistically significant decrease in the mandibular plane angle. Cephalometric analysis of skeletal measurements in patients with low to average mandibular plane angles showed no significant difference between groups, although greater maxillary incisor retraction and less mesial movement of the first molar were noted in the mini-implant group. In patients with a high mandibular plane angle, those receiving skeletal anchorage had genuine intrusion of the maxillary first molar and reduction in the mandibular plane angle, whereas those receiving headgear anchorage had extrusion of the maxillary first molar and an increase of mandibular plane angle. In contrast to the posterior movement in the headgear group, anterior movement of Point A was noted in the mini-implant group. In both the anteroposterior and vertical directions, skeletal anchorage achieved better control than did the traditional headgear appliance during the treatment of maxillary dentoalveolar protrusion. Greater retraction of the maxillary incisor, less anchorage loss of the maxillary first molar, and the possibility of counterclockwise mandibular rotation all facilitated the correction of the Class II malocclusion.

Changes in facial profile during orthodontic treatment with extraction of four first premolars

The present study was designed to evaluate soft tissue profile changes after the orthodontic treatment of class I bimaxillary dentoalveolar protrusion in adult cases. Pre- and post-treatment cephalograms of 20 Caucasian female class I bimaxillary dentoalveolar protrusion patients were selected from private practice. All of them were treated by extraction of four first premolars, and banded and bonded by 022 × 028 standard edgewise technique. t-Test was used to analyze pre- and post-treatment cephalograms. This study showed that upper and lower lip protrusions were decreased respectively 2.7 ± 2.9 mm ( p < 0.001) and 2.8 ± 2.8 mm ( p < 0.001). The mean changes of upper and lower lip thickness and length, as well as nasolabial and labiomental angles were not significant. Significant positive correlation was found between changes of maxillary and mandibular incisors with changes in upper lip ( r UI = 0.70, p < 0.001, r LI = 0.59, p < 0.006) and the lower lip positions ( r UI = 0.64, p < 0.002, r LI = 0.72, p < 0.001). By using stepwise regression it was found that a ratio of 0.63:1 was obtained between upper lip retraction and maxillary incisor retraction and a ratio of 0.62:1 was obtained between lower lip retraction and mandibular incisor changes. This study concluded that, a strong correlation exists between anterior tooth retraction and the position of both lips.

Treatment Outcomes of Orthodontic Treatment, Corticotomy-Assisted Orthodontic Treatment, and Anterior Segmental Osteotomy for Bimaxillary Dentoalveolar Protrusion

The purpose of this study was to compare treatment outcomes of orthodontic treatment, anterior segmental osteotomy, and corticotomy-assisted orthodontic treatment for resolution of bimaxillary dentoalveolar protrusion. The samples consisted of 65 Korean adult female patients with bimaxillary dentoalveolar protrusion who had achieved a good treatment result and were divided into group 1 (orthodontic treatment), group 2 (corticotomy-assisted orthodontic treatment with skeletal anchorage in the maxilla and anterior segmental osteotomy in the mandible), or group 3 (anterior segmental osteotomy in the maxilla and mandible). The hard- and soft-tissue variables were measured from lateral cephalographic tracings at pretreatment and posttreatment stages. Statistic analyses were performed to compare differences in pretreatment and change from pretreatment to posttreatment. Group 3 showed the largest amount of basal bone retraction and the least amount of upper incisor inclination change and upper alveolar bone bending among the three groups. The amounts of change in the upper lip projection and angulation were greater in group 2 than in group 1. Group 3 showed a decrease of the upper incisal exposure, whereas group 1 showed an increase. Upper central incisor to Frankfurt horizontal plane, upper and lower alveolar ridge angle, Pog-N perpendicular, and anteroposterior discrepancy indicator were selected as significant variables for discriminating the three groups. The results of this study show that orthodontic treatment or corticotomy-assisted orthodontic treatment is indicated for those with severe incisor proclination with normal basal bone position, although corticotomy-assisted orthodontic treatment can be advantageous for adult patients concerned with treatment duration. Anterior segmental osteotomy is recommended for bimaxillary dentoalveolar protrusion patients with a gummy smile, basal bone prognathism, relatively normal incisor inclination, and relatively underdeveloped chin position.

Effects of retraction of anterior teeth on horizontal and vertical lip positions in Japanese adults with the bimaxillary dentoalveolar protrusion

The purposes of this study were to evaluate the upper and lower lip changes after orthodontic treatment of bimaxillary protrusion in adult Japanese. We also intended to predict the upper and lower lip positions from the changes of the maxillary and mandibular incisor positions in both the horizontal and vertical planes. Pre-treatment and post-treatment cephalograms of 38 patients (6 males and 32 females, aged 24.2 ± 2.9 and 22.8 ± 4.1 years, respectively) who had four first premolars extracted, were taken with lips in their voluntary relaxed position, traced and compared between them. Stepwise multiple regression analysis revealed that a 1 mm retraction and a 1 mm intrusion of the maxillary incisor cervical point would produce a 0.22 mm retraction of the upper lip, a 1 mm retraction of the mandibular incisor tip would produce 0.76 mm retraction of the lower lip, and a 1 mm mandibular incisor tip retraction would produce a 0.50 mm retraction of Stomion. Moreover, a 1 mm maxillary incisor tip intrusion would produce a 0.56 mm upward movement of the upper lip and a 1.00 mm upward movement of the lower lip. The predictability of this study may be beneficial for orthodontists in planning and discussing treatment plans and options with patients.

Temporary tongue thrust: failure during orthodontic treatment

Abstract This report presents the case of a 25-year-old male patient who sought orthodontic treatment. Oral examination revealed an Angle Class I relation, with a bimaxillary dento-alveolar protrusion, evidence of anterior crowding, and a large overbite and overjet. Radiographic examination revealed a skeletal Class I occlusion. During the distal movement of the canines, occlusal interferences between the canines occurred and the commencement of a tongue thrust was observed. After correction of the applied forces, the canine movement was completed and the habit was no longer detectable. The incident indicates that an unusual oral habit suspiciously occurring during treatment should lead to an immediate reconsideration of the orthodontic treatment strategy.

Integumentaal profile changes after surgical orthodontic correction of bimaxillary dentoalveolar protrusion in black patients

An investigation was undertaken to evaluate the soft-tissue changes of the lips as a result of dentoalveolar setback procedures performed to reduce bimaxillary dentoalveolar protrusion in black patients. Lateral head films of adult 14 patients taken preoperatively and postoperatively were compared to evaluate soft- and hard-tissue changes. A stepwise regression analysis with hard-tissue changes, initial interlabial gap, lip thickness, and lip area as predictor variables was performed to assess their influence on the change in an associated soft-tissue point. Upper lip thickness and horizontal change in PR accounted for 60% of the horizontal variance in the upper lip at SLS, and horizontal change in PR accounted for 80% of the horizontal variance in LS. Lower lip area accounted only for 28% of the horizontal variance in the lower lip at LI. Vertical changes of the upper lip were small and could not be predicted. Vertical changes of the lower lip were small but predictable: IL and lip thickness accounted for 75% of the vertical variance in the lower lip at ILS, and ID accounted for 58% of the vertical variance in LI.

An American board of orthodontics case report

A case report is presented of an Angle Class I dental malocclusion, significant bimaxillary dentoalveolar protrusion, anterior open bite, and spacing of the maxillary and mandibular incisors.

Combined Surgical and Orthodontic Treatment of Bimaxillary Dento-Alveolar Protruvion: Report of Case

The authors treated a case of bimaxillary dentoalveolar protrusion corrected by anterior segmental osteotomies: As presurgical treatment & process, closing of the upper anterior spacing with fixed appliances was worked out, cephalometric predicition & model surgery was done, and fabrication of intra-arch acrylic resin splints were made. It was not necessary to make an intermaxillary fixation with wire after surgery. Only intramaxillary fixation of anterior retracted mobile segment with resin plate was required for 8 weeks. After surgical treatment, leveling of the upper and lower arch with rectangular arch wire were accomplished as the Intrusion of anterior teeth proceeded. We will continue to improve the class II molar relationship by using class II elastics and have a good occlusiion through the orthodontic treatment.

Skeletal open bite associated with bimaxillary dento-alveolar protrusion, evaluation and treatment

A surgical procedure for correction of open bite malocclusion is reported and evaluated. This occlusal problem is often not correctable by orthodontic means. The facial and occlusal improvement was marked and produced better function, speech and appearance. Some relapse has occurred after nine months of observation. Continued observation is suggested. Maxillo-facial surgical corrections require longitudinal study to validate the effectiveness of the treatment.