Thirty-two-year follow-up study of Herbst therapy: A biometric dental cast analysis

Abstract

Introduction: The aim of this study was to analyze the very long-term effects of Herbst treatment on tooth position and occlusion. Subjects: Fourteen patients from a sample of 22 with Class II Division 1 malocclusions consecutively treated with the banded Herbst appliance were reexamined 32 years after therapy. Methods: Dental casts were analyzed from before (T1) and after (T2) treatment, and at 6 years (T3) and 32 years (T4) after treatment. Results: Minor changes in maxillary and mandibular dental arch perimeters and arch widths were seen during treatment (T1-T2) and posttreatment (T2-T4). Mandibular incisor irregularity remained, on average, unchanged from T1 to T2 but increased continuously during the 32-year follow-up period (T2-T4). Class II molar and canine relationships were normalized in most patients from T1 to T2. During the early posttreatment period (T2-T3), there was a minor relapse; during the late posttreatment period (T3-T4), molar and canine relationships remained, on average, unchanged. Overjet and overbite were reduced to normal values in all subjects during treatment (T1-T2). After treatment (T2-T4), overjet remained, on average, unchanged, but overbite increased insignificantly. Conclusions: Thirty-two years after Herbst therapy, overall, acceptable long-term results were seen. Stability was found in 64% of the patients for sagittal molar relationships, in 14% for sagittal canine relationships, in 86% for overjet, and in 86% for overbite. A Class II relapse seemed to be caused by an unstable interdigitation of the occluding teeth, a persisting oral habit, or an insufficient retention regimen after treatment. Most posttreatment changes occurred during the first 6 years after treatment. After the age of 20 years, only minor changes were noted. Long-term posttreatment changes in maxillary and mandibular dental arch perimeters and widths as well as in mandibular incisor irregularity seemed to be independent of treatment and a result of physiologic dentoskeletal changes throughout adulthood. (Am J Orthod Dentofacial Orthop 2014;145:15-27)

Effect of low-intensity pulsed ultrasound (LIPUS) on mandibular condyle growth in rats analyzed with micro-CT

“…Comparison of previously treated children and untreated controls after the second phase revealed that early treatment had little effect on subsequent treatment. Pancherz et al (3) followed patients for 32 years after therapy with a banded Herbst appliance and reported that only 64% of the subjects had a stable sagittal jaw relationship. On the other hand, Xiong et al (4) investigated changes in mandibular morphology of adult rats using fixed bitejumping devices and reported that bite jumping of the mandible in adult rats induced changes in the size and angulation of the condylar process.…”

Optimization of Class II Malocclusion Treatments Using the Forsus™ Fatigue Resistance Device and Its Post-Treatment Effect in Adult Patients: A Case Report

“…The decision to treat this case using the Forsus hybrid functional appliance was taken due to the patient's main complaint, the characteristics of the malocclusion and, mainly, the facial features that have shown facial asymmetry within the normal standards, i.e., convex profile, but with passive lip seal, harmonic nasolabial angle and horizontal growth pattern [1,2,[4][5][6]8,9,12,25,28,30,33,34,35]. Other treatment options were considered unfavorable due to the presented clinical condition and the patient's main complaint and treatment choice.…”

“…Based on this and supported by the literature, it was possible to consider and suggest some treatment options to the patient, such as a surgical-orthodontic treatment [20,38]; upper first molar extractions [39,40], the use of intermaxillary Class II elastics [24,41], which would need patient cooperation; and the use of fixed functional appliances-rigid [18,19,[21][22][23]25], semi-rigid [8,11,12,37], but, mainly, hybrid appliances as the Forsus™ Fatigue Resistant Device [3,7,11,[13][14][15]17,[32][33][34]35]. The chosen protocol was to use the Forsus™ Fatigue Resistant Device that has shown to be an effective device, providing greater comfort to patients [7,11,[14][15][16][17]33,34] and good resistance [10,13,15,35] when treating Class II malocclusions.…”

“…In the twenty-first century, the launch of the Forsus™ Fatigue Resistant Device brought a new proposal to treatments, considering patient comfort in the set-up day and along the treatment, due to the lack of mandibular postural change and easiness of performing the functional mandibular movements [7,11,[14][15][16][17]. Additionally, there are also scientific evidences demonstrating that the impact on growth pattern is temporary after treatment as, in a long-term run, changes responding to growth pattern already exists genetically [3,16,[18][19][20][21][22][23][24][25].…”

Predictive factors of sagittal stability after treatment of Class II malocclusions

“…Reported relapse rates following these treatments range from 20% to 52%. [2][3][4][5][6] Relapse, however, cannot be predicted at the individual level. 7 Moreover, relapse tendencies vary in extent and clinical significance.…”