Incisor Relationship Research Articles

Post-orthodontic cephalometric variations in bimaxillary protrusion cases managed by premolar extraction - A retrospective study.

Bimaxillary protrusion is a common dentofacial condition associated with proclination of maxillary and mandibular incisors in relation to the dental and cranial bases resulting in soft tissue procumbency. The present retrospective study aimed to investigate dental and soft tissue profile changes using cephalometric analysis to evaluate bimaxillary protrusion patients after extraction of the first four premolars and subsequent retraction of the anterior teeth. Pre-treatment and post-treatment cephalometric radiographs of 46 Saudi patients (16 males and 30 females), 18-30 years of age with bimaxillary protrusion, were selected based on inclusion criteria. Dental and soft tissue landmarks were traced using the Dolphin® imaging software and statistically analyzed with SPSS® 21 software. The upper and lower incisors retroclined by a mean value of 9.6° and 9.65°, respectively, and an average distance of 4.1 mm. The level of maxillary incisor exposure was reduced by approximately 1.1 mm after treatment. A mean increase of 6.6° in the nasolabial angle was also observed. Multiple regression analysis showed that retraction of both upper and lower incisors by 1 mm would result in a 0.44 mm retraction of the upper and lower lips. A statistically significant increase in the nasolabial angle and upper lip length was found in relation to upper and lower incisor retraction and retroclination. A significant reduction was also evident in the post treatment upper incisor exposure, facial convexity angle and mentolabial sulcus depth.

The prevalence of malocclusion and orthodontic treatment need of school children in Northern Saudi Arabia.

OBJECTIVE:To evaluate the incidence of malocclusion and requirement for orthodontic treatment in the Saudi region of Hail city.MATERIALS AND METHODS:520 Saudi participants between 7 and 12 years from Hail city were used in the research, all of whom were selected using a simple randomization method. For every participant, various malocclusion variables such as molar, canine, and incisor relationship, overjet, overbite, open bite, cross bite, scissor cross bite, and the score for the orthodontic treatment need [Index of Orthodontic Treatment Need (IOTN)] were recorded. A light source was used for examination, in addition to mouth mirrors, a calibrated ruler, and a portable dental chair.RESULTS:The prevalence of class I molar relationship was 70.4%, with class II being 21.3% and class III being 8.3%. As for the incisor relationships, class I was found at a prevalence of 72.5%, class II at 19.8%, and class III at 7.7%. Additionally, the following malocclusion characteristics were also found: deep overbite (>4 mm) (16.2%), increased overjet (>4 mm) (14.4%), posterior cross bite (13.3%), anterior open bite (7.7%), anterior cross bite (5.2%), scissor bite (4%), and posterior open bite (0.6%). A total of 4.4% were identified as requiring orthodontic treatment. Grades 1 and 2 were 25.5% and 58.5%, respectively. There was a significant relationship found between grades 3 and 4, and the anterior open bite, cross bite, and scissor bite.CONCLUSION:This research showed that class I malocclusion was most dominant, followed by classes II and III, respectively. When the Hail city school pupils in the study were assessed for IOTN index, grades 3 and 4 were found to be highly related to anterior open bite, cross bite, and scissor bite.

Evaluation of the miniplate-anchored Forsus Fatigue Resistant Device in skeletal Class II growing subjects: A randomized controlled trial.

To evaluate the use of direct miniplate anchorage in conjunction with the Forsus Fatigue Resistant Device (FFRD) in treatment of skeletal Class II malocclusion. Forty-eight females with skeletal Class II were randomly allocated to the Forsus plus miniplates (FMP) group (16 patients, age 12.5 ± 0.9 years), Forsus alone (FFRD; 16 patients, age 12.1 ± 0.9 years), or the untreated control group (16 subjects, age 12.1 ± 0.9 years). After leveling and alignment, miniplates were inserted in the mandibular symphysis in the FMP group. The FFRD was inserted directly on the miniplates in the FMP group and onto the mandibular archwires in the FFRD group. The appliances were removed after reaching an edge-to-edge incisor relationship. Data from 46 subjects were analyzed. The effective mandibular length significantly increased in the FMP group only (4.05 ± 0.78). The mandibular incisors showed a significant proclination in the FFRD group (9.17 ± 2.42) and a nonsignificant retroclination in the FMP group (-1.49 ± 4.70). The failure rate of the miniplates was reported to be 13.3%. The use of miniplates with the FFRD was successful in increasing the effective mandibular length in Class II malocclusion subjects in the short term. The miniplate-anchored FFRD eliminated the unfavorable mandibular incisor proclination in contrast to the conventional FFRD.

Determination of downs hard tissue cephalometric norms for Himachali Mongoloid tribes

ObjectiveThe purpose of this study was (a) to establish hard tissue cephalometric norms for the population of Himachali Mongoloid tribes, (b) to study the sexual dimorphism in hard tissue cephalometric norms of this population and (c) to compare the Himachali Mongoloid norms with the norms established by Downs. Material and methodSixty Himachali Mongoloid subjects were selected on the basis of Angle’s Class I molar relationship, well aligned arches, full complement of teeth, having clinically acceptable facial esthetics, no previous history of Orthodontic treatment, subjects native of the tribal belt of Himachal Pradesh. Lateral head films were traced and Downs cephalometric parameters were recorded. Statistical analysis was done to compare the difference between the established norm and the norm established by Downs for the Caucasian population. ResultSignificant difference was seen in the Angle of convexity, with Himachali Mongoloid tribe population having a more forwardly positioned middle part of the face. This population had less steeper cant of occlusal plane, more acute interincisal angle, more inclined lower incisors in relation to the mandibular and the occlusal plane and more forwardly positioned maxillary incisor in relation to the A-pog line. ConclusionThese findings suggested that ethnic differences in the facial traits exist and awareness of dentofacial pattern of each ethnic group will ensure better success of the treatment in establishing optimal facial harmony.

The characteristics of dental occlusion in patients with moderate to severe obstructive sleep apnea in Saudi Arabia.

Objectives:To evaluate characteristics of dental occlusion among non-obese Saudi adult patients suffering from moderate to severe obstructive sleep apnea(OSA).Methods:Following ethical approval, a cross-sectional study was conducted at Sleep Disorders Center, King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia, between January and March 2017. Non-obese adult Saudi patients with moderate/severe OSA (apnea-hypopnea index>15) and without history of malocclusion or edentulism were included with an estimated sample size of 50. Demographic details and severity of OSA as diagnosed by polysomnography were recorded. Characteristics of dental occlusion, namely molar, canine and incisor relationship, overjet, overbite, crossbite and arch form were obtained through calibrated examiners (kappa 0.81). Descriptive statistical analysis and Chi-square test, with 95% significance level (p<0.05), were used to identify relationships between the severity of OSA and characteristics of dental occlusion.Results:A total of 51 patients (31 males, 20 females; mean age 49.45±10.35 years), were enrolled in the study. Severity of OSA was moderate in 17 patients and severe in 34 patients. Severe form of OSA was more among males (64.7%) and in patients with Class-II division-1 incisor relationship (94.1%). Neither the demographic characteristics, nor characteristics of dental occlusion showed statistically significant relationship with the severity of OSA.Conclusion:The results of the present cross-sectional study indicate that the characteristics of dental occlusion are not related to the severity of OSA among non-obese adult Saudi patients.

Skeletal Class III correction in permanent dentition using reverse twin block appliance and fixed mechanotherapy

The orthodontic management of patients with Class III malocclusion poses numerous prognostic and treatment challenges to the clinician. Various removable, orthopaedic, myofunctional and fixed appliances have been recommended for the correction of Class III malocclusion. The Reverse Twin Block (RTB) is a simple and well tolerated appliance which has often been used for the early management of such cases in mixed dentition. Cases reporting use of RTB in permanent dentition are however, limited. This article presents an insight into the encouraging results of reverse twin block (RTB) appliance used in conjunction with fixed mechanotherapy for the successful treatment of a 12-year-old patient presenting with skeletal Class III malocclusion and a concave facial profile. The RTB appliance helped establish a favourable environment for unrestricted maxillary growth, at the same time redirecting the mandibular growth to a clockwise direction and correcting the incisal relationship. The favourable treatment outcome and long-term stability achieved substantiates the feasibility of RTB appliance in mild to moderate skeletal Class III malocclusions in permanent dentition cases.

MANEJO ESTOMATOLÓGICO DE UN PACIENTE PEDIÁTRICO CON DISTROFIA MUSCULAR DE DUCHENNE. REPORTE DE UN CASO

La Distrofia muscular de Duchenne (DMD) es una enfermedad ligada al cromosoma X, que afecta aproximadamente 1 de cada 3,300 varones nacidos vivos. Es causada por la ausencia o la mutación del gen que codifica la proteína distrofina. El propósito de este caso fue revisar la literatura actual sobre los aspectos importantes de atención infantil en la DMD. PRESENTACIÓN DE CASO: Acude a la clínica de Odontopediatría, un paciente masculino de 8 años de edad con discapacidad para la marcha y constitución ectomorfica, diagnosticado médicamente de DMD. A la exploración intraoral se encontró: clase I de Angle, mordida borde a borde anterior, diastemas, apiñamiento anteroinferior, gingivitis localizada, caries activas y macroglosia relativa. El manejo estomatológico fue realizado en cuatro fases: Preventiva, Restauradora, Quirúrgica y Mantenimiento. Se logró gran éxito clínico, requiriendo de un trabajo multidisciplinario, para proporcionarresultados satisfactorios a largo plazo que incrementen la calidad de vida del paciente.

Complete analysis of space in the dental arch used in the Tweed-Merrifield technique as a key to prepare a maximally individual plan of orthodontic treatment

The Tweed-Merrifield technique is based on a simple and detailed diagnosis and therapy considering a shape of the dental arch with preservation or improvement of facial features.&lt;b&gt; Aim&lt;/b&gt;. The aim of the work was to present a reliable and structured method to analyse diagnostic models used in the Tweed-Merrifield technique. &lt;b&gt;Material and methods&lt;/b&gt;. Based on a review of available literature the paper presents rules to assess an amount of space in the arch for tooth movements used in the Tweed-Merrifield technique. The analysis of models in this technique is based on the assessment of three segments of the dentition: anterior, middle and posterior. With regard to each segment actual width of teeth and amount of space available in the arch is measured. Additionally, in the anterior segment evaluation of alignment of lower incisors in relation to FMIA (Frankfort Mandibular Incisor Axis Angle) or IMPA (Lower Incisor Mandibular Plane Angle) cephalometric angles as well as assessment of the soft tissues thickness is important. With regard to the middle segment of the dentition measurement of the curve of the Spee plays an important role, and with regard to the posterior segment it is also necessary to evaluate expected growth in patients at the developmental age. &lt;b&gt;Conclusion&lt;/b&gt;. A detailed assessment of possible tooth movements and treatment management taking into account an initial shape of the arch allow to obtain stable therapeutic outcomes. &lt;b&gt;(Warmuz J, Kawala B, Minch L. Complete analysis of space in the dental arch used in the TweedMerrifield technique as a key to prepare a maximally individual plan of orthodontic treatment. Orthod Forum 2017; 13: 283-90).&lt;/b&gt;

Bilateral Transposition Of Maxillary Canines And First Premolars : Orthodontic Management. A Case Report

Introduction: Transposition is a rare dental anomaly in positional interchange between two adjacent teeth. Studies indicated that tooth transpositions are more frequent unilateral than bilateral (12:1). It is a very rare phenomenon when the anomaly is bilateral and affects same teeth on both sides. The case of a 17 year old girl, with class I incisor relationship on class 1 skeletal base with bilateral transposition of maxillary canines-first premolars, severe crowding and posterior crossbite, is presented. This case report demonstrates the orthodontic management of bilateral transposition of maxillary canines-first premolars and by the end of treatment, the transpositions were maintained while achieving a good functional and aesthetic result.

Effect of incisal loading during orthodontic treatment in adults: A randomized control trial.

To measure the changes in tooth mobility, alveolar bone, and receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) in the gingival crevicular fluid (GCF) during orthodontic treatment to regain incisal function in the presence and absence of biting exercises. Thirty-six females (42.3 ± 6.5 years old) with periodontally compromised upper incisors received orthodontic treatment to obtain ideal incisor relationships. Eighteen subjects in the experimental biting exercise group were instructed to bite a soft plastic roll for 5 min/d; the 18 control subjects were not given plastic rolls. Alveolar bone thickness, height, and density around the upper incisors were assessed at three root levels using cone-beam computed tomography. GCF was collected at the labial and palatal sites of the upper incisors at pretreatment (T0), end of treatment (T1), 1 month after T1 (T2), and 7 months after T1 (T3). RANKL/OPG was determined using enzyme-linked immunosorbent assays. Labial and palatal bone thickness significantly increased (>twofold) from T1 to T3 in the experimental group at all three root levels (all P < .05). Bone thickness correlated negatively with RANKL/OPG ratio between T1 and T2 ( P < .05). Tooth mobility, bone height, and density were not significantly different between T1 and T3. Biting exercises significantly increased bone thickness but did not affect tooth mobility, bone height, or density. The RANKL/OPG ratio decreased 1 month after treatment (T2) and correlated with increased bone thickness. ( ClinicalTrials.in.th TCTR20170625001).

Interdisciplinary treatment in an adult patient with skeletal class III malocclusion and retained upper canines: case report

Introduction: Class III malocclusion is considered the most severe within the classification of malocclusions. In most patients, the etiology may be divided in skeletal and dentoalveolar components. In the adult patient, because skeletal growth has ceased, treatment options are reduced to two possibilities: camoufl age or orthognathic surgery. These complex cases require careful planning, a multidisciplinary approach and patient cooperation. Material and methods: A 44-year-old female with skeletal class III malocclusion, brachyfacial biotype, concave profi le, bilateral molar class III, nonassessable canine class due to the presence of temporary canines; an edge-to-edge incisor relationship and anterior crossbite of the temporary canines. Objective: To improve the maxillo-mandibular relationship obtaining good occlusal function as well as to improve the aesthetics of the patient through a multidisciplinary treatment. Results: Maxillo-mandibular relationship was improved, canine guidance was achieved with implants and prosthesis, a bilateral class I molar relationship was obtained as well as good occlusal function. Periodontal health was maintained. Conclusion: The multidisciplinary approach was successful in achieving the desired therapeutic results of improved function, improved aesthetics and improved self-esteem in this patient.

A three-dimensional soft tissue analysis of Class III malocclusion: a case-controlled cross-sectional study.

The present study used the optical surface laser scanning technique to compare the facial features of patients aged 8-18 years presenting with Class I and Class III incisor relationship in a case-control design. Subjects with a Class III incisor relationship, aged 8-18 years, were age and gender matched with Class I control and underwent a 3-dimensional (3-D) optical surface scan of the facial soft tissues. Landmark analysis revealed Class III subjects displayed greater mean dimensions compared to the control group most notably between the ages of 8-10 and 17-18 years in both males and females, in respect of antero-posterior (P = 0.01) and vertical (P = 0.006) facial dimensions. Surface-based analysis, revealed the greatest difference in the lower facial region, followed by the mid-face, whilst the upper face remained fairly consistent. Significant detectable differences were found in the surface facial features of developing Class III subjects.

Treatment of a class II malocclusion complicated by digit-sucking

This article describes the management of a 12-year-old girl who presented with a Class II division 1 incisor relationship on a Class II skeletal base with an overjet of 10 mm and a thumb-sucking habit. This patient was treated with a modified Herbst appliance to correct the Class II skeletal pattern and break her thumb-sucking habit. CPD/Clinical Relevance: It is important to recognize a digit-sucking habit early as this needs to be eliminated prior to starting orthodontic treatment. This can complicate treatment of patients who require treatment with functional appliances.

Interdisciplinary case of multiple congenitally missing permanent teeth.

Background: Patients presenting with congenitally missing teeth are relatively common and the aim of the dental team is to create a functional, healthy, and aesthetically acceptable dentition. The consequences of missing teeth include an abnormal occlusion or an altered facial appearance which may lead to psychological distress in some patients.Methods: The present case report describes a 23 year old patient with non-syndromic, congenitally missing permanent teeth (CMMPT). Clinical and radiographic examinations revealed agenesis of eight permanent teeth including the third molars. Following interdisciplinary treatment planning, the patient was treated with mechano therapy to correct a class III incisal relationship by space closure in the lower arch. In the upper arch, the right canine was substituted for a missing lateral incisor and space was opened for a prosthetic left lateral incisor (a mini implant).Results: Active orthodontic treatment was completed in 19 months. The management of CMMPT requires an interdisciplinary approach to achieve improved occlusal function and aesthetics.Conclusion: A combined orthodontic-implant-prosthodontic treatment approach can achieve an improved functioning occlusion, and favorable aesthetics.Bangladesh Journal of Medical Science Vol.16(3) 2017 p.467-473

Occlusal Features and Caries Experience of Hong Kong Chinese Preschool Children: A Cross-Sectional Study.

Objective: To study occlusal features and their relation to caries experience in Hong Kong Chinese preschool children. Methods: Seven kindergarten classes in Hong Kong were selected using a stratified random sampling method, and the 4- and 5-year-old Chinese kindergarten children were invited to join the survey. Two calibrated dentists performed the clinical examinations in the kindergartens. Occlusion features, including incisal overjet; canine and molar relationship; median diastema; and primate space as well as malocclusion features, including crossbite; anterior open bite; and scissor bite, were recorded. Caries experience was recorded with the dmft index. Results: A total of 538 children were invited to participate in the study, and finally 495 children were examined (92%). Approximately half (52%) had a normal incisor relationship. Most children had a class I canine relationship (left-79%; right-75%). Approximately two-thirds had a flush terminal plane (left-64%; right-65%). Most children (76%) had a maxillary primate space, and 47% had a mandibular primate space. The prevalence of median diastema, anterior crossbite, and unilateral posterior crossbite was 30%, 12% and 1%, respectively. No bilateral posterior crossbite or scissor bite was found. Approximately half (49%) had caries experience. The mean dmft score was 2.1. Gender and age were not associated with either the studied occlusal features or the mean dmft score (p > 0.05). Conclusion: Approximately half of the Hong Kong preschool children studied had a normal occlusion, and two-thirds of them had a flush terminal plane. About three-quarters of them had a maxillary primate space, and half of them had a mandibular primate space. Their occlusal traits were not associated with caries experience and prevalence.

Changes in Smile Proportions Concomitant to Extraction and Non- Extraction Orthodontia (A Comparative Study)

Objective: An attractive, well-balanced smile is a paramount treatment objective of modern orthodontic therapy. The purpose of this study was to compare changes in smile proportions among extraction and non-extraction therapy cases and to correlate them with the accompanying hard and soft tissue changes. Material and Methods: A sample of 24 patients with an age range of 14.3-24.9 years, requiring fixed orthodontic treatment was divided into group I (extraction therapy cases) and group II (nonextraction therapy cases). Dentofacial characteristics of the 2 groups were obtained from close up smile photographs and lateral cephalometric analyses before and after treatment. independent student “t” test to compare between both groups before and after treatment, Paired student “t” test to evaluate the change within the same group and Pearson’s correlation analysis to evaluate correlations between selected parameters. Results: Aftertreatment, maxillary incisor display showed significant increase in the nonextraction group also, maxillary gingival display showed significant increase in the extraction group (P < 0.05). When the two groups were compared, after treatment, the extraction group showed significant higher values in the posterior corridor ratio and maxillary gingival display (P < 0.05). The posterior corridor ratio was negatively correlated with lower anterior facial height (r = -0.579).The amount of incisor display during smile was positively correlated with the inclination of maxillary incisors in relation to the skullbase U1/SN (°) (r = 0.499) and with maxillary incisors protrusion measured as U1/NA distance (r = 0.676). Conclusion: the results revealed that the extraction therapy cases showed higher values in the posterior corridor ratio and maxillary gingival display than the non extraction therapy cases. The significant relationship of incisor protrusion and inclination with the amount of incisor display and the significant relationship of lower anterior facial height with the posterior corridor ratio must be considered when planning orthodontic treatment

Cephalometric study of Class II Division 1 patients treated with an extended-duration, reinforced, banded Herbst appliance followed by fixed appliances.

The Herbst appliance has been used in the treatment of Class II malocclusions with deficient mandibles. Various protocols, including different durations of the orthopedic treatment phase and stepwise advancement of the mandible, have been advocated for increasing the orthopedic effects. The objective of this study was to investigate the skeletal and dental changes in patients treated with a reinforced banded Herbst appliance for an extended duration and fixed appliance therapy. The study group consisted of 30 patients (16 boys, 14 girls; mean age, 12.3±2.5years) with Class II Division 1 malocclusions who were successfully treated with the new Herbst protocol followed by fixed appliances. Lateral cephalometric radiographs were taken before treatment, at the completion of Herbst treatment, and after removal of fixed appliances. The average treatment times were 1.5±0.7years for the Herbst treatment and 1.8±0.5years for the fixed appliances. A control Class II sample from the Bolton-Brush study was used to subtract growth from treatment changes to determine the appliance effect. Data were analyzed using analysis of variance and the Tukey-Kramer test. After the Herbst treatment, the incisal relationships of all subjects had been overcorrected to end-to-end relationships. Overjet was reduced by 7.2mm after subtracting changes from growth. The skeletal contribution was 2.5mm (35%), and the dental contribution was 4.7mm (65%). The molar relationship was overcorrected to a more Class I relationship by 7.5mm. The Wits appraisal was improved by 4.2mm. Vertically, overbite was decreased by 3.3mm. The maxillary and mandibular molars were extruded by 1mm. The occlusal plane rotated clockwise by 5° with little change in the mandibular plane angle. After the treatment with fixed appliances, the overjet correction was maintained at 7.6mm. The skeletal contribution was 2.9mm (38%), and the dental contribution was 4.7mm (62%). The molar relationship was corrected to a Class I relationship by 5.9mm. The Wits appraisal was improved by 3.2mm. Vertically, overbite was decreased by 4.2mm. The maxillary and mandibular molars were extruded by 0.3 and 0.8mm, respectively. The occlusal plane rotated clockwise by 1.2° with little change in the mandibular plane angle. Doubling the usual orthopedic treatment time with the reinforced Herbst appliance followed by fixed appliance therapy was effective in correcting Class II Division 1 malocclusions with excess overjet and overbite. In this sample of successfully treated patients, most changes after Herbst and fixed appliance therapy were dentoalveolar (62%). However, the skeletal changes attained in the orthopedic phase of treatment were maintained after fixed appliance therapy.

Long-Term Incisal Relationships After Palatoplasty in Patients With Isolated Cleft Palate

Various palatoplasty techniques have limited incisions in the hard palate due to concerns that these incisions may limit maxillary growth. There is little convincing long-term evidence to support this. Our purpose is to determine incisal relationships, an indicator for future orthognathic procedure, in patients after repair of an isolated cleft of the secondary palate. Our craniofacial database was used to identify patients aged 10 years or greater with an isolated cleft of the secondary palate who underwent palatoplasty between 1985 and 2002. Data collected included age at palatoplasty and follow-up, cleft type, associated syndrome, Robin sequence, surgeon, repair technique, number of operations, and occlusion. Incisal relationship was determined through clinical observation by a pediatric dentist and orthodontist. Seventy eligible patients operated on by 9 surgeons were identified. Class III incisal relationship was seen in 5 patients (7.1%). Palatoplasty techniques over the hard palate (63 of 70 patients) included 2-flap palatoplasty, VY-pushback, and Von Langenbeck repair. There was an association between class III incisal relationship and syndromic diagnosis (P <0.001). Other study variables were not associated with class III incisal relationships. In patients with an isolated cleft of the secondary palate, there was no association between class III incisal relationship and surgeon, age at repair, cleft type, palatoplasty technique, or number of operations. Increased likelihood of class III incisal relationship was associated primarily with syndromic diagnosis.

The British Orthodontic Society MOrth cases prize 2014.

This paper describes the orthodontic treatment of two cases that were successful in winning the British Orthodontic Society (BOS) Membership in Orthodonitcs (MOrth) cases prize in 2014. The first case describes the management of a 26-year-old female with a Class II division 2 incisor relationship on a Class III skeletal base with reduced vertical proportions. This was complicated by: an unerupted ectopic palatally displaced upper right permanent canine, an erupted palatally displaced upper left permanent canine, retained deciduous canines, generalised microdontia, an overall Bolton tooth size discrepancy, mild crowding in the upper arch, an increased overbite (complete to tooth tissue) and crossbites. Treatment involved a surgical exposure of the ectopic canine and the use of fixed pre-adjusted edgewise appliances over a period of 24 months. The second case describes the management of a 12-year-old female with a Class II division 2 incisor relationship on a Class 2 skeletal base with reduced vertical proportions. This was complicated by: an increased overjet and overbite (complete to soft tissue), mild upper and lower arch crowding and an increased naso-labial angle. Treatment involved an initial phase of modified Clark Twin Block and sectional fixed appliances followed by complete fixed pre-adjusted edgewise appliances over a period of 24 months.

Botulinum toxin as a therapeutic agent to prevent relapse in deep bite patients.

The etiology of deep bite is multifactorial. One of the causes is increased muscular activity. This makes the treatment of deep bite malocclusions difficult and often results in relapse in many cases. In this work we compared patients with surgical orthognathic treatment only and surgical orthognathic treatment with additional injections of botulinum toxin after mandibular advancement for class II division 2 malocclusion. This is a prospective study. Adult patients were assessed pretreatment (T1), posttreatment (T2), and long-term after 1 year (T3). In total, 32 patients (mean age, 30.7 years; 23 women and 9 men) reached the study end point (T3); 24 patients were treated without botulinum toxin and 8 patients received preoperative injections of botulinum toxin. Significant differences between both groups were observed, with a more stable result for the experimental group treated with botulinum toxin. In a selective group of adult patients with a class II division II incisor relationship and with a class II skeletal base, botulinum toxin injections can effectively prevent relapse. This may present an alternative to a conventional myotomy.