AIMS: To identify if lower incisor movements after orthodontic treatment are due to the relapse of the orthodontic treatment or due to natural growth. SUBJECTS AND METHODS: The subjects consisted of 92 patients who have had orthodontic treatment, divided into three groups, group 1: 38 individuals had no retainer in the lower jaw. Group 2: 24 individuals had a retainer 0.028 inch, a spring hard wire bonded to the mandibular canines only. Group 3: 30 individuals had a 0.0195-inch Twist-Flex wire, bonded to all mandibular incisors and canines. Study models before orthodontic treatment (T0), immediately after orthodontic treatment (T1), 6 years after orthodontic treatment (T2), and 12 years after orthodontic treatment (T3) were used for the measurements. The wires in groups 2 and 3 were removed after mean 2.6 years (SD 1.49). Little Irregularity Index (LII), inter-canine distance, available mandibular anterior space, and number of crowded incisors were registered. A Tooth Displacement Index (TDI) was developed to measure the tooth displacement directions at T0 and T3. RESULTS: The LII showed equal values before treatment (T0) and at the follow-up registrations (T2 and T3). But about 25 per cent of the tooth displacements at T2 and T3 did not exist before treatment, at T0. This indicates usual growth changes and not relapse of the orthodontic treatment. CONCLUSION: As about 25 per cent of the displaced incisors can be considered as an effect of natural growth, not a relapse of the orthodontic treatment, it is valuable to use a displacement index in combination with other variables for investigations of stability after orthodontic treatment. Importance of the present study is that it is possible to differ between relapse and usual growth changes.

Agenesis of mandibular second premolar is reported to be 2.4-4.5%. The diagnosis can be set on at average 9 years of age. Early treatment in the form of extraction of the second primary molar and in some cases also the remaining three second premolars and comprehensive orthodontic treatment are often a good treatment solution. In vertical deep bite cases, cases with spacing in the dental arch, mandibular posterior rotation and for extractions disadvantageous growth pattern, a treatment with retaining of the primary molar must be taken in consideration. When there is no or minor infraocclusion, root resorption less than half of the root length, and no caries or fillings at the age of 12-13 years, there is a good prognosis for longtime survival of the primary molar.

The purpose of this investigation was to evaluate whether access to computed tomography (CT) influences orthodontists' decision-making about management of incisor root resorption due to ectopic maxillary canines. The study base comprised orthodontic specialists and active members of the Swedish Orthodontic Society: 182 orthodontists under 65 years of age, who had been registered specialists for at least one year and were providing specialist treatment for regular orthodontic patients. A questionnaire was sent out, comprising 8 questions about management and decision-making in cases of ectopic maxillary canines with root resorption of adjacent incisors and 7 questions about practice profile. The orthodontists were asked whether they altered their treatment decisions when CT was available as a diagnostic tool. The response rate was high, 86%. Sixty of the orthodontists had access to CT. Sixty-one percent of the 97 orthodontists without access to CT stated that, in cases with space deficiency, they seldom or never considered extraction of a lateral incisor with suspected root resorption if the resorption was not discernible on intra-oral or panoramic radiographs. It was evident that even in cases of root resorption of lateral incisors due to ectopic canines, the orthodontists' management decisions were not particularly influenced by availability of CT diagnostic data. In the extraction cases 55% of the orthodontists considered extraction of the affected incisor first when root resorption was severe, i.e. involving the pulp and 37% when the resorption reached half way to the pulp. in cases without space deficiency 82% preferred to extract these resorbed lateral incisors not until the resorption reached the pulp.

OBJECTIVE: To document and analyze factors involved in decision-making by orthodontists in managing disturbances of eruption of maxillary canines. MATERIAL AND METHODS: The participants comprised orthodontic specialists and active members of the Swedish Orthodontic Society. Those selected for the study sample were under 65 years of age or younger and had been treating orthodontic patients for at least 1 year as a specialist. Three typical cases were presented for treatment proposals. The case notes, including radiographs and specific background data, were sent to the 182 selected orthodontists. The orthodontists were also requested to complete a questionnaire about practice profile, comprising eight questions. RESULTS: The response rate was 86.3%; yielding 157 participants (mean age 53.8 years, SD 8.12). Analysis disclosed no differences between responders and nonresponders regarding age, gender, and years of specialist practice. For treatment plans based on panoramic radiographs, intraoral radiographs, and status and anamnesis, there was general consensus. However, when supplementary information from computer tomography (CT) was provided, disclosing root resorption half-way to the pulp or more on the lateral incisor, the orthodontists' treatment proposals varied. Gender, age, and practice profile of the orthodontists had little association with the decision-making. CONCLUSIONS: Supplementary CT information led to variations in decision-making with respect to treatment of eruption disturbances of maxillary canines. This lack of consensus among specialist orthodontists can have negative implications for patients.

A total of 61 children who had 83 maxillary canines impacted were followed up for a mean of 3.5 years (range 1.1-10.9 years) after treatment to evaluate the long-term results of the treatments. In most of the children, the impacted maxillary canines had been surgically exposed and treated with fixed orthodontic appliances. In 11 cases, lateral incisors had been extracted because of extensive root resorption. The esthetic results as well as functional and periodontal conditions were evaluated. Only four of the 61 children were not satisfied with the esthetic result, whereas orthodontists judged only 56% of the results as esthetically acceptable on clinical evaluation and 57% as es-thetically acceptable on color slides. The periodontal conditions and the occlusal function on sides with previously impacted canines and on sides with normally erupted canines, on the whole, were similar. Exceptions were pocket depths of the left lateral incisors and left canines, but these variables were significantly different mainly because of one patient. In lateral movements of the mandible, however, significant differences in contact pattern were found between sides with normally erupted canines and sides with impacted canines. Canine rise occurred more often on working sides with normally erupted canines than with impacted canines.

Objective: To evaluate mandibular irregularity index stability following orthodontic treatment facilitated by alveolar corticotomy and augmentation bone grafting (Cort+). Materials and Methods: The irregularity index of 121 orthodontically treated and 15 untreated patient study casts was analyzed at 5 years and 10 years. Results: Cort+ resulted in significantly lower mandibular irregularity index scores at both 5 years (1.5 mm vs 4.2 mm, P , .000) and 10 years (2.1 mm vs 4.1 mm, P , .000) compared with conventionally treated patients. Conclusions: Unmatched samples advise caution with conclusions, but orthodontic therapy combined with Cort+ enhanced the stability of the postorthodontic mandibular irregularity index for at least 10 years in this preliminary study.

INTRODUCTION: The aim of this study was to analyze the very long-term results after Herbst treatment with respect to changes in the mandibular incisor segment: incisor inclination, incisor alignment, and gingival status. METHODS: Fourteen patients were derived from a sample of 22 consecutive patients with Class II Division 1 malocclusions treated with the banded Herbst appliance. Intraoral photographs, mandibular dental casts, and lateral head films were analyzed from before (T1, age 12.5 years) and after (T2, age 14 years) treatment, and at 6 years (T3, age 20 years) and 32 years (T4, age 46 years) after treatment. RESULTS: At T1, incisor inclination in the 14 subjects was, on average, 100.1°. From T1 to T2, the incisors were proclined in 11 (79%) of the 14 patients, with an average value of 5.2°. Maximum proclinations of 10° were found in 2 subjects. From T2 to T4, tooth inclination recovered completely in 7 (63%) of the 11 patients. Incisor irregularity values were, on average, 3.4 mm at T1 and 3.0 mm at T2. These increased from T2 to T4 by 40% and had an average value of 5.0 mm at T4. Clinically insignificant labial gingival recessions on single front teeth were registered in 1 subject at T2 and in 8 subjects at T4. Gingival recessions were seen especially on bodily displaced incisors. CONCLUSIONS: In Herbst patients followed for 32 years after therapy, proclined mandibular incisors generally rebounded. The increase in posttreatment incisor tooth irregularity was not thought to be related to incisor tooth inclination changes but more likely resulted from physiologic processes occurring throughout life. Minor gingival recessions (especially on bodily displaced and crowded canines and incisors) seen in a few patients, 32 years after treatment, seemed not to be related to the posttreatment tooth inclination changes.

INTRODUCTION: The aim of this longitudinal 32-year follow-up investigation was to analyze the very long-term effects of Herbst treatment on the dentoskeletal structures. We followed 14 patients from a sample of 22 with Class II Division 1 malocclusions who were consecutively treated with the banded Herbst appliance at ages 12 to 14 years. The subjects were reexamined after therapy at the ages of 20 years (when the radius epiphysis/diaphysis plate was closed) and 46 years. METHODS: Lateral head films were analyzed from before (T1) and after (T2) treatment, and at 6 years (T3) and 32 years (T4) after treatment. RESULTS: (1) In the standard analysis (angular measurements) during the T2 to T3 period of 6 years, significant skeletal changes were the following: increase of the SNB (1.0°; P <0.01), decrease of the ANB (0.9°; P <0.01), and decrease of the ML/NSL (2.5°; P <0.001). During the T3 to T4 period of 24 years, no further significant angular changes occurred. (2) In the analysis of the sagittal changes in the occlusion (linear measurements) during the T2 to T3 period of 6 years, the mandible (6.1 mm; P <0.001) and the maxilla (3.0 mm; P <0.01) grew forward. During the T3 to T4 period of 24 years, the mandible (2.8 mm; P <0.01) and the maxilla (3.1 mm; P <0.01) continued to grow forward. Thus, during the total posttreatment (T2-T4) period of 32 years, there was continuous forward growth of the mandible (8.9 mm; P <0.001) and the maxilla (6.1 mm; P <0.001). (3) The analysis of superimposed lateral head films showed in all 14 subjects large amounts of sagittal and vertical skeletofacial growth during T3 to T4. CONCLUSIONS: In all 14 subjects, large amounts of sagittal and vertical skeletofacial growth occurred after the age of 20 years. However, the question of when, during the period from 20 to 46 years, growth had come to an end remains open. Closure of the radius epiphysis/diaphysis plate is not useful as an indicator for completed skeletofacial growth. Our findings indicate the importance of considering late adult skeletofacial growth in dentofacial orthopedics, orthognathic surgery, and tooth implantology with respect to treatment timing, posttreatment retention, and relapse.

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.

Objective:  To analyze radiographic signs of temperomandibular joint (TMJ) osteoarthritis and clinical TMJ symptoms in patients 6 years and 32 years after treatment with a Herbst appliance. Materials and Methods:  Fourteen patients were derived from a sample of 22 with Class II division 1 malocclusions consecutively treated with a banded Herbst appliance at the age of 12–14 years old (T1-T2). The subjects were reexamined after therapy at the ages of 20 years (T3) and 46 years (T4). The TMJs of the 14 patients were analyzed radiographically (conventional lateral tomography at T3 and cone-beam computed tomography at T4) and clinically/anamnestically at T3 and T4. Results:  Six years after Herbst therapy, signs of osteoarthritis were seen in one patient. At the 32-year follow-up, two additional patients had developed signs of osteoarthritis. At the 6-year follow-up, TMJ clicking was present in two patients, though none of the patients reported TMJ pain. At the 32-year follow-up, six patients had TMJ clicking and one patient had TMJ pain. Conclusions:  This longitudinal very-long-term follow-up study after Herbst therapy revealed only minor problems from the TMJ. The TMJ findings 6 years and 32 years after Herbst treatment corresponded to those in the general population. Thus, in the very long term, the Herbst appliance does not appear to be harmful to the TMJ.

The aim of the present study was to disclose the treatment procedures most frequently recommended by Swedish orthodontists for use by general practitioners and to determine whether these recommendations are reflected in the undergraduate dental program in orthodontics at Malmo University. Potential differences between the orthodontists' recommendations were also investigated. A questionnaire was sent to 169 consulting orthodontists, seeking their recommendations for appliance therapy to be undertaken by general practitioners: 129 (63 males and 66 females) responded. The Quad Helix was the appliance most commonly recommended for correction of posterior crossbite, a plate with Z-springs for correction of anterior crossbite and the headgear activator for correction of Class II malocclusions. A significant gender difference was disclosed with respect to orthodontists' recommendations for treatment of Class II malocclusions by general practitioners, namely that female orthodontists recommended the headgear activator more frequently than males. However, this difference is most likely attributable to the gender distribution among orthodontists qualifying as specialists during the last five decades: more recently qualified orthodontists are predominantly female. The choice of appliances corresponded well with undergraduate training in orthodontics at the Faculty of Odontology in Malmo.

Stability of Unilateral Posterior Crossbite Correction in the Mixed Dentition - a 3-year Follow-Up. Aim: To compare and evaluate long-term stability of crossbite correction with Quad Helix or expansion plate in the mixed dentition. Methods: In this RCT-study 35 patients with unilateral posterior crossbite were randomized to be treated with either Quad Helix or expansion plate. The inclusion criteria were: mixed dentition, unilateral posterior crossbite, no sucking habits or previous orthodontic treatment. Stability was evaluated after 3 years by study cast measurements. Twenty subjects with normal occlusion were included as controls. Success rate, maxillary and mandibular transverse dimensions, overjet and overbite were registered. Results: Stability was equal for the two treatment methods. Small, albeit significant, differences between the groups were assessed with reference to transverse dimensions. No significant difference was seen for overjet and overbite. Conclusions: The long-term stability of posterior crossbite correction with Quad helix and expansion plate was equal.

Aim: To compare and evaluate long-term stability of crossbite correction with Quad Helix or expansion plate in the mixed dentition. Methods: In this RCT-study 35 patients with unilateral posterior crossbite were randomized to be treated with either Quad Helix or expansion plate. The inclusion criteria were: mixed dentition, unilateral posterior crossbite, no sucking habits or previous orthodontic treatment. Stability was evaluated after 3 years by study cast measurements. Twenty subjects with normal occlusion were included as controls. Success rate, maxillary and mandibular transverse dimensions, overjet and overbite were registered. Results: Stability was equal for the two treatment methods. Small, albeit significant, differences between the groups were assessed with reference to transverse dimensions. No significant difference was seen for overjet and overbite. Conclusions: The long-term stability of posterior crossbite correction with Quad helix and expansion plate was equal.

INTRODUCTION: The long-term stability of posterior crossbite correction in the mixed dentition has not been sufficiently evaluated. Our aim was to compare long-term outcomes in patients with crossbite correction by using matched controls with normal occlusion.

METHODS: After 35 patients were treated for crossbite with a quad-helix or an expansion plate, we used randomized controlled trial methodology to follow them for 3 years posttreatment. All had fulfilled our pretreatment criteria: mixed dentition, unilateral posterior crossbite, no sucking habits, and no previous orthodontic treatment. Transverse relationships, maxillary and mandibular widths, overbite, overjet, arch lengths, and midlines were registered on the study models immediately before and after treatment and at the follow-up 3 years after treatment. The matched control group comprised 20 subjects with normal occlusion and was compared with the first and last registrations for the treated groups.

RESULTS: At follow-up, changes in the treatment groups were equal and stable. The changes were comparable with the control group. All other changes were minor and had no clinical implications. The long-term effect of crossbite correction on midline deviation was unpredictable.

CONCLUSIONS: If crossbite is successfully corrected by the quad-helix appliance or the expansion plate, similar long-term stability is achieved. However, in treated patients, mean maxillary widths never reached those of normal control subjects.

Stability of Unilateral Posterior Crossbite Correction in the Mixed Dentition - an RCT-study with 3-year Follow-Up. Aim: To compare and evaluate long-term stability of crossbite correction with Quad Helix or expansion plate in the mixed dentition. Methods: In this RCT-study 35 patients with unilateral posterior crossbite were randomized to be treated with either Quad Helix or expansion plate. The inclusion criteria were: mixed dentition, unilateral posterior crossbite, no sucking habits or previous orthodontic treatment. Stability was evaluated after 3 years by study cast measurements. Twenty subjects with normal occlusion were included as controls. Success rate, maxillary and mandibular transverse dimensions, overjet, overbite and arch length were registered. Results: Stability was equal for the two treatment methods. Small, albeit significant, differences between the groups were assessed with reference to transverse dimensions. No significant difference was seen for overjet and overbite. The treated patients never reached the same transversal width as the normal control group. Conclusions: The long-term stability of posterior crossbite correction with Quad helix and expansion plate was equal. The maxillary width was greater in the control group than the treated groups.

There are few cost evaluation studies of orthodontic treatment. The aim of this study was to determine the costs of correcting posterior crossbites with Quad Helix (QH) or expansion plates (EPs) and to relate the costs to the effects. To determine which alternative has the lower cost, a cost-minimization analysis was undertaken, based on that the outcome of the treatment alternatives is identical. The study comprised 40 subjects in the mixed dentition, who had undergone treatment for unilateral posterior crossbite: 20 with QH and 20 with EPs. Duration of treatment, number of appointments, broken appointments, and cancellations were registered. Direct costs (for the premises, staff salaries, material and laboratory costs) and indirect costs (loss of income due to parent's assumed absence from work) were calculated and evaluated for successful treatment alone, for successful and unsuccessful treatment and re-treatment when required. The QH had significantly lower direct and indirect costs, with fewer failures requiring re-treatment. Even the costs for successful cases only were significantly lower in the QH than in the EP group. The results clearly show that in terms of cost-minimization, QH is the preferred method for correcting posterior crossbite in the mixed dentition.

Introduction: The aim of this work was to analyze the dental and skeletal changes in patients treated with fixedorthodontic appliances with or without retention appliances, and to compare the changes with untreated sub- jects. Specifically, mandibular incisor irregularity was analyzed. Methods: A total of 105 children who had undergone orthodontic treatment with fixed appliances in both jaws were examined in 2 groups: 64 had a lingual mandibular retainer and 41 had no retainer. Retention time was 2.7 +/- 1.5 years. The untreated group consisted of 25 subjects. Measurements were done on study casts and lateral head radiographs before and after treatment and 6 and 12 years after treatment. The Little irregularity index (LII) was the most important variable. Results: No differences were found in LII 12 years after treatment between the group that had a retainer and the group without a retainer after treatment. In the untreated group, LII was increased over time, but not to the same extent as in the treated groups. Correction of overjet and overbite was stable long-term. At the last examination, the amount of overjet was almost the same in all 3 groups. Conclusions: The routine use of mandibular retainers for 2 to 3 years does not appear to prevent long-term relapse. If the patient wants to constrain natural development and changes, lifelong retainers are needed.

Objective: To compare the long-term outcome 9 years after removal of two different types of fixed retainers used for stabilization of the mandibular anterior segment. Materials and Methods: Sixty-four children who had undergone orthodontic treatment with fixed appliances in both arches were divided into two groups depending on which kind of retainer being used. Twenty-eight of the patients had a canine-to-canine retainer bonded to the canines and 36 had a bonded twistflex retainer 3-3, bonded to each tooth. Measurements were made on study models and lateral head radiographs, before and after treatment, 6 years after treatment, and 12 years after treatment, with a mean of 9.2 years after removal of the retainers. Results: No significant differences were found between the two groups at the long-term follow-up according to Little's Irregularity Index or available space for the mandibular incisors. The overjet and overbite were reduced after treatment in both groups and stayed stable throughout the observation period. Also, no differences in bonding failures between the two retainers were found. Conclusions: Both a canine-to-canine retainer bonded only to the canines and a twistflex retainer 3-3 bonded to each tooth can be recommended. However, neither of the retention types prevented long-term changes of mandibular incisor irregularity or available space for the mandibular incisors after removal of the retainers.

SUMMARY There is lack of consensus with respect to the preferred surgical procedure for the treatment of palatally impacted maxillary canines. The aim of this study was to evaluate post-treatment periodontal status of palatally impacted canines treated by open technique with free eruption and closed flap technique and compare it with naturally erupted canines. The subjects comprised 43 patients treated for unilateral palatally impacted maxillary canines and examined 4.19±1.44 months (3–6 months) after removal of the fixed appliance. The group 1 comprised subjects treated by open technique with free eruption (n = 22) and group 2 by closed technique (n = 21). Post-treatment examination comprised periodontal and radiographic examination. There were no significant intergroup differences with respect to periodontal pocket depth or bone support. However, compared with contralateral quadrants with normally erupted canines, quadrants with impacted canines exhibited significant bone loss at the distal contact point of the lateral incisor and the mesial contact point of the canine. The duration of treatment was 28.41±4.96 months for group 1 and 32.19±11.73 months for group 2 (P > 0.05). The mean treatment time required to achieve eruption/extrusion of the impacted canine was 3.05±1.07 months for group 1 and 6.86±4.53 months (P < 0.01) for group 2. It is concluded that choice of surgical method is not associated with any significant differences in post-treatment periodontal status of palatally impacted canines and adjacent teeth.

Dentoalveolar changes in adulthood have not been extensively documented. Such changes may have important implications for the long-term stability of orthodontic treatment. To analyse occlusal and dentoalveolar changes in adults from the age of 20 years to the age of 60 years. The material comprised 18 Swedish dentists, 16 men and 2 women, with no missing teeth and no prosthodontic or orthodontic treatment. Measurements were recorded on study casts made between 1949 and 1989 at the Department of Stomatognathic Physiology at the Faculty of Odontology in Malmö, thus documenting changes over an average period of 38.4 years. Malocclusion traits, overbite, overjet, dental arch length and width, and Little’s irregularity index were registered. There was a significant increase in Little’s irregularity index in the mandible (1.0 mm, P < 0.01) and a decrease in arch length in both jaws (0.5–0.9 mm, P < 0.05). The maxillary and mandibular intercanine widths decreased by 0.8 and 1.0 mm, respectively (P < 0.001). The malocclusion traits, overbite, and overjet remained unchanged during the observation period. The results confirm that dentoalveolar changes occur as a continuous process throughout adult life. The findings of potential clinical importance are decreases in arch length and depth, resulting in a decrease in intercanine width and an increase in anterior crowding. In clinical orthodontic practice, these findings have important implications for treatment planning and long-term stability after orthodontic treatment.