Treatment of Class II, Division 2 in the late growth period

The "Deckbiss" with skeletal Class II jaw relationship sometimes presents a considerable therapeutic problem, particularly in the late growth period (DP3U), as regards the coordination of dental and skeletal treatment objectives. An effective treatment approach was demonstrated: a modified Herbst appliance used simultaneously with fixed appliances in the maxilla. The sample comprised 12 male (14.0 +/- 0.9 years old) and 10 female (12.3 +/- 0.4 years old) patients. Correction of the distal occlusion was achieved in all patients by means of the Herbst appliance, which was removed after an average time period of 6.4 +/- 0.2 months. In the mandible the multibracket appliances were then immediately inserted, and Class II elastics were used for retention. Maximum anchorage was required in the maxilla as well as in the mandible. Complete diagnostic records were made at the beginning of the treatment as well as 6 and 12 months later, in order to document skeletal and dental changes. A dental and skeletal Class I relationship was achieved in all cases. A significant improvement was recorded in the vertical jaw base relationship; this was still stable after a period of 12 months. In the dental area in particular, a so-called high-pull headgear effect (intrusion and distalization 16, 26) and intrusion of teeth 34, 44 were registered. Only a minor protrusion of the mandibular incisors was observed. Reinforcement of the bands reduced the failure rate significantly. The Herbst appliance does not represent a standard treatment for Class II. Its indication range is limited.     

Guiding occlusal development with functional appliances

Functional appliances have been used in orthodontics since their introduction by Pierre Robin almost one hundred years ago, however, our understanding of how they bring about orthodontic correction is still limited. This article is a brief overview of their history, mode of action, advantages and disadvantages, and includes the results of a study of attempts to control and minimise their side-effects using a recent development in functional appliances: the 'Teuscher Appliance'. This appliance combines a high-pull headgear with the activator, and is designed to reduce the often reported side-effects of functional appliances. The skeletal and dentoalveolar effects of treatment with the Teuscher Appliance on 40 consecutively-treated patients are reported and illustrated with four individual case reports. The results showed that the skeletal effect on the maxilla was a retardation of the normal forward and downward growth in 80 per cent of the cases, and that mandibular growth in 70 per cent of cases was forward. In patients whose mandibular growth was primarily in a vertical direction, such growth could be ascribed mainly to posterior rotation of the maxilla and/or the fact that the acrylic covering the lower posterior teeth to correct a deep bite was removed, promoting the eruption of these teeth and increasing the anterior vertical development. The dentoalveolar changes were characterised by retroclination of the maxillary incisors in 90 per cent of the patients, and were due to insufficient torque control by the built-in torque springs, which need further development. The mandibular incisors were well controlled by capping. The statistical analysis showed an inverse correlation between the initial incisor inclination and the change during treatment. This suggests that proclination of the lower incisors, as previously reported, is not a contra-indication to functional appliance treatment, provided the appliance is correctly designed. Overall, this study showed considerable individual response to treatment, and that the occlusal correction occurred through a combination of skeletal and dentoalveolar changes.     

Skeletal anchorage system for open-bite correction

A skeletal anchorage system was developed for tooth movements. It consists of a titanium miniplate that is temporarily implanted in the maxilla or the mandible as an immobile anchorage. In this article, we introduce the skeletal anchorage system to intrude the lower molars in open-bite malocclusion and evaluate the results of treatment in two severe open-bite cases that underwent orthodontic treatment with the system. Titanium miniplates were fixed at the buccal cortical bone around the apical regions of the lower first and second molars on both the right and left sides. Elastic threads were used as a source of orthodontic force to reduce excessive molar height. The lower molars were intruded about 3 to 5 mm, and open-bite was significantly improved with little if any extrusion of the lower incisors. No serious side-effects were observed during the orthodontic treatment. The system was also very effective for controlling the cant and level of the occlusal plane during orthodontic open-bite correction.     

The effect of treatment with the Bass appliance on skeletal Class II malocclusions: a cephalometric investigation

The purpose of this investigation was to study the short-term effects of treatment with the Bass appliance by comparative evaluation of treated and untreated skeletal Class II malocclusions. The subjects consisted of forty-seven Class II, division 1 malocclusion cases. Twenty-seven (14 girls, 13 boys) were treated with the Bass appliance for an average of 6 months. The remaining 20 cases (6 girls, 14 boys) served as a control. At the end of the 6 month treatment period the statistically significant treatment changes could be summarized as follows: the sagittal skeletal relationship was improved as a result of favourable growth responses in both the maxilla and the mandible. The overjet was reduced and the molar relationship was corrected as a result of the extended skeletal changes. Distal movement of the upper dentition was evident, with unchanged inclination of the maxillary incisors. Both anterior and posterior facial heights were increased without changes in the inclinations of the palatal and mandibular planes. No significant dental movement was observed in the mandible.     

A modified, lingually supported cantilevered Herbst appliance

This new, fixed-functional appliance/Herbst/Bioprogressive system is designed for patient comfort and mandatory compliance. It also combines the positive clinical effects of four fixed-functional systems. It allows rapid palatal expansion of the upper arch, alveolar uprighting of the lower arch, upper and lower incisor alignment, and sagittal correction of Class II malocclusions to occur simultaneously with one appliance fixed in both arches. It is indicated for use in growing patients with skeletal Class II malocclusions. The ideal timing for treatment is the late mixed dentition. Being able to remove the appliance after one year with the upper second bicuspids erupting slightly Class III so the clinician can immediately begin fixed finishing mechanics would be ideal. This new Herbst design will reduce the frequency of orthognathic surgery and upper bicuspid extraction to camouflage Class II malocclusions. At the same time, it gives total control to the clinician in treating some more difficult, non-compliant patients. Fixed-functional appliances, which improve treatment efficiency and treatment results and provide for patient comfort, while at the same time give the treating clinician almost total control of the three planes of facial growth will open new doors for orthodontic treatment and research in the next century.     

Condylar condition and mandibular growth during early functional treatment of children with juvenile chronic arthritis

TMJ involvement in children with Juvenile Chronic Arthritis (JCA) will frequently cause disturbance of the growth of the mandible. Orthodontic treatment of these patients often includes orthognathic surgery, and are complicated to handle with respect to the damaged joint and impaired function. The aim of this presentation is to suggest an early treatment with a functional splint appliance, a distraction splint, with the purpose of increasing function of the joint and ensuring continuous growth of the mandible.     

Studies on the hypotensive and bradycardic effects of 1-piperidinylmethyl-2-naphthol hydrochloride

An understanding of growth and development and the effect our appliances have on a person's growth and development is necessary in the selection of the therapeutic appliances we choose to use, out of the multitude available. Timing of treatment is also important in effecting positive changes in skeletal and dental relationships. Early treatment to correct skeletal discrepancies and gain arch length can allow for an increase in nonextraction therapy. Cervical extraoral appliances, maxillary fixed expansion appliances, and mandibular labial "E" arches can be used early to effectively reduce of skeletal discrepancies and to gain arch length without the fear of rotating the mandible down and back, permanently increasing the mandibular plane angle. Case reports are presented to illustrate the beneficial changes that can occur with early treatment with these appliances.     

Intraepiphyseal resection of the proximal tibia and its impact on lower limb growth

From 1989 through 1996, 10 children affected by high grade bone tumors of the proximal tibia underwent an intraepiphyseal intercalary resection. The residual epiphyseal bone segment measured less than 2 cm in thickness in all cases and reconstruction always was performed using the combination of a vascularized fibular autograft and a massive bone allograft. The proximal epiphyseal osteosynthesis was fixed by small fragment screws. The aim of this study was to report the growth pattern of the residual proximal tibial epiphysis and to evaluate any possible lower limb discrepancy and/or deformity after the end of skeletal maturity. At current followup six patients were available for the final evaluation. Radiographic documentation included computed tomography scan of both knees before surgery, a panoramic radiographic view and a computed tomography scan of both lower limbs after the end of skeletal growth. The length of both femurs and tibias, the size of the tibial plateau and of the opposite distal femur, and any possible deformity of femur or tibia were measured and compared with the preoperative data. No patient had a limb length discrepancy greater than 3.5 cm. In all cases the ipsilateral femur had a valgus deformity of the hip develop. In two patients this deformity was associated with an elongation of the femur, partially compensating for the shortening of the tibia. The tibial plateau close to reconstruction grew less than the contralateral one (range 2%-8%) but maintained its normal relationship with the distal femur. None of these patients reported any restriction in recreational activities. They could walk, run, and jump. Their functional result according the International Society of Limb Salvage functional grading system was satisfactory in all cases.     

Magnetic activator device II (MAD II) for correction of Class II, division 1 malocclusions

A magnetically active, two-piece (upper and lower), functional orthopedic appliance has been developed, magnetic activator device (MAD) for the correction of Class II malocclusions. The magnetic forces are used to give freedom of mandibular movement and to allow for continuous functioning of the orofacial muscles when the appliance is worn. Samarium cobalt (Sm2Co17) magnets are incorporated on the buccal aspects of the upper and lower appliances. Magnetic forces ranging from 150 to 600 gm per side have been used on patients, and it seems that the skeletal versus dental response depends on the intensity of the magnetic force used. A force of 300 gm, when the magnets are in contact, on each side has been found to be an appropriate value in patients age 7 to 12 years. The use of this less bulky design rather than a traditional orthopedic appliance, along with the freedom of function it permits, has enabled patients to wear the appliance nearly 24 hours in most cases.     

Treatment response to maxillary expansion and protraction

A prospective clinical trial was conducted to determine the skeletal and dental contributions to the correction of overjet and overbite in Class III patients. Thirty patients (12 males and 18 females with a mean age of 8.4 +/- 1.7 years) were treated consecutively with protraction headgear and fixed maxillary expansion appliances. For each patient, a lateral cephalogram was taken 6 months before treatment (T0); immediately before treatment (T1); and 6 months after treatment (T2). The time period (T1-T0) represented changes due to 6 months of growth without treatment; (T2-T1) represented 6 months of growth and treatment. Each patient served as his/her own control. Cephalometric analysis described by Bj?rk (1947) and Pancherz (1982a,b) was used. Sagittal and vertical measurements were made along the occlusal plane (OLs) and the occlusal plane perpendicular (OLp), and superimposed on the mid-sagittal cranial structure. The results revealed the following: with 6 months of treatment, all subjects were treated to Class I or overcorrected to Class I or Class II dental arch relationships. Overjet and sagittal molar relationships improved by an average of 6.2 and 4.5 mm, respectively. This was a result of 1.8 mm of forward maxillary growth, a 2.5-mm of backward movement of the mandible, a 1.7-mm of labial movement of maxillary incisors, a 0.2-mm of lingual movement of mandibular incisors, and a 0.2-mm of greater mesial movement of maxillary than mandibular molars. The mean overbite reduction was 2.6 mm. Maxillary and mandibular molars were erupted occlusally by 0.9 and 1.4 mm, respectively. The mandibular plane angle was increased by 1.5 degrees and the lower facial height by 2.9 mm. Individual variations in response to maxillary protraction was large for most of the parameters tested. Significant differences in treatment changes between male and female subjects were found only in the vertical eruption of mandibular incisors and maxillary and mandibular molars. These results demonstrate that significant overjet and overbite corrections can be obtained with 6 months of maxillary protraction in combination with a fixed expansion appliance.     

Twin Block appliance. Part II

The main purpose of the Twin Block is to advance the mandible and to correct moderate to severe overjets. When the first molars are encouraged to erupt, the Twin Block also results in a partial correction of the overbite. The Rick-A-Nator or Rick-A-Nator 2 Appliances are utilized to hold the mandible in a forward position and also to help erupt the bicuspids to complete the orthopedic correction of the overbite. It is vital that the total treatment time for the active phase with the Twin Block and the support phase with the Rick-A-Nator be a minimum of 15 to 18 months to allow for permanent muscular, skeletal and dental changes to be accomplished.     

A case of bilateral optic neuropathy and recurrent transverse myelopathy associated with perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA)

The purpose of this study was to evaluate skeletal and dental effects of bionator headgear combination appliances on patients in development period with Class II, division 1 malocclusion. The comparison of computerized X-ray cephalometric measurements between the 26 treated children and 26 untreated children was made. The results showed that ANB angle was significantly reduced and horizontal mandibular growth development tended to be normal in the treated group. It was suggested that the bionator headgear combination appliance can restrain the maxillary growth early and promote the forward mandibular growth which contribute the functional jaws correction.     

Costochondral grafts to replace mandibular condyles in juvenile chronic arthritis patients: long-term effects on facial growth

Long-term facial growth and clinical outcome after replacement of arthritic mandibular condyles by costochondral grafts and postoperative orthodontic guidance of the occlusion were studied until completion of facial growth in patients (n = 12) with juvenile chronic arthritis (JCA) affecting their temporo-mandibular joints (TMJs). The patients were between 10.1 and 16.7 years of age at surgery. Clinical records and radiographs for cephalometric measurements were taken preoperatively, 6-8 weeks after surgery and after completion of facial growth. A considerable potential for growth of the costochondral graft/mandible unit was demonstrated in all patients. The results also indicated a considerable risk of asymmetrical mandibular overgrowth (n = 8), which could not be correctly assessed until after skeletal maturation was complete. Without any active orthodontic treatment, compensatory growth of the alveolar processes closed the lateral open bites, which were created during surgery. The functional results of the reconstructed temporo-mandibular joints were good and the morbidity rate was low. Costochondral grafting is a versatile treatment when the TMJs are severely affected by JCA, but requires supervision of patients until skeletal maturation, to monitor possible mandibular overgrowth. Advantages of this method were re-established mandibular growth, good mandibular function, a low morbidity rate and early aesthetic improvement.     

Longitudinal evaluation of growth changes in Class II division 1 subjects

Longitudinal records from the Ohio State University Growth Study were used to compare the skeletal growth changes between Class II division 1 and Class I female subjects between ages 7 and 14. Tensor analysis was used to determine the yearly growth rate and direction. No significant difference was found in cranial base dimension between the Class I and Class II subjects. In Class II subjects, the maxilla (S-N-A) was found to be normally related to the cranial base. However, mandibular position (S-N-B and S-N-Pog) was found to be significantly more retrusive in Class II when compared with Class I subjects. Mandibular length (Ar-Gn) and corpus length (Go-Gn) were found to be shorter in Class II subjects. The ratio of PFH to AFH was found to be smaller in Class II subjects. This is particularly apparent during the pubertal growth period. The y-axis and mandibular plane angle were more open in Class II subjects which also contributed to the retrusive position of the mandible. Maxillo-mandibular difference (A-N-B) between Class I and II subjects was present at age 7 and persisted through puberty, maintaining a greater angle of convexity (A-N-Pg) in Class II subjects. These results suggest that Class II malocclusion can be detected early. The majority of the Class II cases showed mandibular skeletal retrusion or a combination of horizontal and vertical abnormalities of the mandible rather than maxillary protrusion. These skeletal differences remain through puberty without orthodontic intervention. Individual variations were found within each type of malocclusion.     

Maxillary development revisited: relevance to the orthopaedic treatment of Class III malocclusions

Normal development of the maxilla results not only from movements of its constituent skeletal units and bony apposition-resorption superficially, but also from the specific development of the antero-lateral regions. In Class III cases, correction of the skeletal dysmorphosis requires not only that the maxilla is in a correct position (in relation to the mandible) and that the correct occlusion is achieved, but also that there is good development of the exo-peri-premaxilla. This requires normalization of muscular posture (labio-mental, lingual, velo-pharyngeal) and of orofacial functions (nasal ventilation, swallowing, mastication). Postero-anterior traction using an orthopaedic mask can only accomplish part of the treatment of Class III. The action must always be complimented by other therapy aimed at correcting the underdevelopment of the antero-lateral regions. Facemask therapy is not only simple sagittal distraction, but is truly a method for treatment of Class III which is well understood and achieves excellent results. Taking into account the great diversity of anatomical forms of Class III malocclusion, it is not surprising that extra-oral postero-anterior traction gives widely varying results. The quality, however, depends principally on the method used. Orthodontists must not hesitate to call for the assistance of a surgeon each time the functional treatment is insufficient, particularly in cleft patients where the results depend more on surgical procedures, both primary and secondary, than on dentofacial orthopaedics.     

A cephalometric analysis of six Twin Block patients. A study of mandibular (body and ramus) growth and development

A study of the effect of the Twin Block appliance on the underdeveloped mandible. Significant growth has been measured cephalometrically and charted on 6 patients, 4 males and 2 females, who have worn the Twin Block for approximately one year. With Pre-Twin Block cephalometric taken, the Twin Block was inserted and bite blocks were advanced approximately every 8 weeks. Progress and Post-Twin Block cephalometric (lateral) radiographs show a significant increase in ramus height and mandibular body length. The purpose of this article is to demonstrate actual mandibular bone growth. A number of the subjects still are in the process of finishing their fixed bracketing phase, and we hope to follow this article with another, demonstrating post Twin Block occlusion and other case finishing factors.     

Aspects of the humoral immune response to Staphylococcus intermedius in dogs with superficial pyoderma, deep pyoderma and anal furunculosis

In order to evaluate the long term clinical and morphologic results of recapture of a displaced TMJ disk, we recalled for follow-up MR imaging 75 patients who had been treated by attempted disk recapture based on pre-treatment MR imaging 1-6 years earlier. The treatment included a day appliance with inclines to guide the mandible into the therapeutic position and a telescopic night appliance which prevented retrusion of the mandible during sleep. Appliance treatment was followed by rebuilding or resurfacing the posterior teeth of one arch to permanently support the mandible in the therapeutic position. After treatment of 115 joints with displaced disks, 52% of the disks were normally positioned, 23% were improved in position, and 25% showed persistent disk displacement. Symptom relief was 92% in patients with normalized (recaptured) disks, 84% in patients with improved disk position, and 49% in patients with persistent disk displacement. Failure to improve disk position occurred in 7% of the joints with anterior disk displacement and in 44% of the joints with a transverse (sideways) component to the displacement. Forty-five percent of the recaptured-disks improved in contour. We concluded that anterior mandibular repositioning was effective in the treatment of patients with reducing displaced disks primarily when the disks were displaced only in an anterior direction. This treatment can be recommended in anterior disk displacements if the patient has failed more conservative treatment measures, permanent occlusal reconstruction can be justified, and the patient understands that long-term use of a night appliance may be necessary. Anterior mandibular repositioning appears much less effective in cases with a transverse component to the disk displacement.     

Intermaxillary forces during activator treatment

The mode of action of the activator appliance is still unclear. Apart from a possible mandibular growth enhancing effect, some investigators believe that orthopedic forces may be applied to the maxilla, contributing to Class II correction by inhibition of maxillary growth. In addition, orthodontic forces may arise that produce dentoalveolar changes. The purpose of this study was to measure the magnitude of anteroposterior intermaxillary forces during wear of the activator appliance. Ten consecutive patients with Class II dental and skeletal relationships were treated with a modified activator appliance. The appliance had maxillary and mandibular segments that could be detached from each other during the measuring session. A force transducer was placed at the anterior part of the maxillary segment, and the anteroposterior force exerted by the mandibular segment was measured. Measurements were taken in the upright and reclined position at every patient visit for a period of 6 months. Results indicated that intermaxillary forces were generally in the orthodontic range (median values of 100 gf at the upright position and 123 gf at the reclined position). A wide variation in force levels was noted, both between patients and for the same patient during the experimental period. No statistically significant change in force levels was observed during the 6 month period and no difference was noted between upright and reclined posture.     

Expansion

Expansion of dental arches has been in practice for a long time and will be around for years to come. Correct diagnosis along with familiarity of the appliance to be used will enhance the results of orthodontic treatment. The NPE incorporates many of the functions that exist in several different appliances. It can be used for maxillary corrections, crossbites, distal rotation and expansion of molars, molar stabilization, auxiliary placement for habit correction, intrusion of molars, three-way Saggital with utility arch, as an aid in Class II correction retainer, etc. It can be used in primary dentition, mixed dentition, adult dentition, cleft palate patients, surgery cases, Class III cases, and TMJ cases. Most patients can benefit from the use of this one appliance. I will continue to use the NPE and possibly discover more uses for it as I work with it.     

Aging of the population: demographics for the Liege region

We present the case of a 26-year-old man who at the age of 9 suffered severe trauma to both maxillary central incisors. The underlying malocclusion was skeletal and classified as dental Class II/1 with severe crowding. Both the maxillary central incisors and the two lower first premolars were extracted and the patient was treated with an edgewise appliance for 2 years. Acceptable occlusal relationships were achieved following orthodontic and adjunctive treatment which consisted of reshaping the maxillary lateral incisors with composite materials and grinding the canines to resemble lateral incisors. A critical evaluation of the esthetic and functional results at the age of 26 years is presented.