The Effects of Multi-Day vs. Single Pre-exercise Nitrate Supplement Dosing on Simulated Cycling Time Trial Performance and Skeletal Muscle Oxygenation.

Jo, E, Fischer, M, Auslander, AT, Beigarten, A, Daggy, B, Hansen, K, Kessler, L, Osmond, A, Wang, H, and Wes, R. The effects of multiday vs. single pre-exercise nitrate supplement dosing on simulated cycling time trial performance and skeletal muscle oxygenation. J Strength Cond Res 33(1): 217-224, 2019-A transient augmentation in the metabolic efficiency of skeletal muscle is the purported basis for dietary nitrate supplementation amongst competitive and recreational athletes alike. Previous studies support the ergogenic effects of nitrate supplementation, as findings indicated improved microvascular blood flow, exercise economy, and performance with relatively short-term supplementation. As with most ergogenic aids, the optimum duration of supplementation before performance or competition, i.e., loading phase, is a critical determinant for efficacy. Therefore, the purpose of this study was to investigate the effects of long-term vs. single dosing nitrate supplementation on skeletal muscle oxygenation and cycling performance. In a randomized, placebo controlled, double blind, parallel design study, healthy, recreationally active men (n = 15) and women (n = 14) subjects (age = 18-29 years) completed an 8 km (5 mi) simulated cycling time trial before and after a 14-day supplementation period with either a nitrate supplement (Multi-Day Dosing Group) (n = 14) or placebo (Single Pre-Exercise Dosing Group; SD) (n = 15). Both groups consumed a single dose of the nitrate supplement 2 hours before the post-treatment time trial. In addition, skeletal muscle oxygenation was measured via near-infrared spectroscopy during each time trial. Multiday nitrate supplementation significantly decreased time to completion (p = 0.01) and increased average power (p = 0.04) and speed (p = 0.02) from pre-to post-treatment, while a single dosing produced no significant changes to these measures. There were no significant differences over time and across treatments for any other measures including muscle oxygenation variables. Overall, long-term nitrate supplementation appears to have an advantage over a single pre-exercise dosing on cycling performance and metabolic efficiency as indicated by an increase in power output with no change in oxygenation.

Glass-ionomer open exposure (GOPEX) versus closed exposure of palatally impacted canines: a retrospective study of treatment outcome and orthodontists' preferences.

Objectives: To investigate which surgical technique orthodontists prefer for exposing palatally impacted canines (PICs), and to compare closed exposure and glass-ionomer open exposure (GOPEX) with regard to pre- and post-surgical orthodontic variables. Materials and methods: A questionnaire with 19 questions and three cases visualising superficial, deep, or medial PICs was sent to 48 orthodontists working in a Swedish county. Sixty case records for patients with unilateral PICs from two centres were analysed; 30 patients having GOPEX (Centre A), and 30 undergoing closed exposure (Centre B). Pre- and post-surgical orthodontic variables were collected from the dental records. Results: The response rate was 81 per cent. There was an equal distribution of preference between open and closed exposure. Glass-ionomer cement (GIC) was predominately used as surgical packing in open exposure. No active traction was initiated until the canine erupted spontaneously. In the closed exposure cases, traction started shortly after exposure. The clinicians mentioned similar advantages of choosing one technique over the other and the main basis for the decision was the clinician's preference and not the location of the canine. There were no differences regarding post-exposure complications between the techniques. The overall treatment time was the same but there were fewer appointments and significantly shorter active treatment time with traction of the PIC in the GOPEX group. Limitations: Despite the homogeneity of the baseline patient characteristics, pre- and post-surgical orthodontic variables were analysed retrospectively, therefore, it is difficult to assess what impact these confounding factors may have had on the treatment time. Conclusions: The choice of exposure technique depends on the clinician's preferences. The active treatment time is shorter and the number of appointments fewer with open exposure when GIC is used as surgical packing.

A cost-minimization analysis of large overjet reduction with two removable functional appliances based on a randomized controlled trial.

Objective: The purpose of this study was to assess and relate the societal costs of reducing large overjet with a prefabricated functional appliance (PFA), or a slightly modified Andresen activator (AA), using a cost-minimization analysis (CMA). Design, settings, and participants: A multicentre, prospective, randomized clinical trial was conducted with patients from 12 general dental practices. Ninety-seven patients with an Angle Class II, division 1 malocclusion, and an overjet of ≥6 mm were randomly allocated by lottery to treatment with either a PFA or an AA. The PFA and AA groups consisted of 57 and 40 subjects, respectively. Blinding was not performed. Duration of treatment, number of scheduled/unscheduled appointments, and retreatment were registered. Direct and indirect costs were analysed with reference to intention-to-treat (ITT), successful (S), and unsuccessful (US) outcomes. Societal costs were described as the total of direct and indirect costs, not including retreatments. Interventions: Treatment with a PFA or an AA. Results: The direct and societal costs were significantly lower for the PFA than for the AA group. The number of visits was lower in the PFA group, when ITT was considered, and for the US cases as well. No difference in retreatment rate could be seen between the groups. Limitations: Costs depend on local factors and thus should not be generalized to other settings. Harms: No harms were detected during the study. Conclusion: The success rate of the both appliances was low. However, the PFA was the preferred approach for reduction of a large overjet in mixed dentition, since it minimized costs and there were no difference in clinical outcomes between PFA and AA. Registration: This trial was registered at 'FoU i Sverige' (http://www.fou.nu/is/sverige), registration number: 97131. Protocol: The protocol was not published before trial commencement.

Discomfort, expectations, and experiences during treatment of large overjet with Andresen Activator or Prefabricated Functional Appliance: a questionnaire survey.

BACKGROUND: The purpose of this study was to investigate the amount of functional and social discomfort experienced after 1 and 6 months of appliance wear, comparing a slightly modified Andresen Activator (AA) and a Prefabricated Functional Appliance (PFA). METHODS: Ninety-seven patients randomly selected by lottery in an AA (40 subjects), and a PFA (57 subjects) group, with an Angle Class II, Division 1 malocclusion, were eligible for the study. One month and 6 months after start of treatment, a questionnaire, addressing discomfort, perception of treatment need and outcome, was used. RESULTS: The response rate was 69% after 1 month, and 45% after 6 months. The most common discomfort reported was the 'appliance falling out during sleep' followed by 'difficulties in remembering it'. The only difference was for pain, which was experienced more extensively in the AA group after 1 month of treatment. The dentist appeared to have the greatest impact on the decision to initiate treatment. Teasing, because of appearance, occurred in 13% of the cases. CONCLUSIONS: No difference could be seen between groups for the experience of functional or social discomfort after 6 months of appliance use. Adequate time should be allowed for clarifying treatment difficulties, using treatment need as motivation. PRACTICAL IMPLICATIONS: The PFA eliminates the need for taking impressions. Furthermore, it can be economically advantageous to both patients and clinicians.

Treatment of large overjet in Angle Class II: division 1 malocclusion with Andresen activators versus prefabricated functional appliances-a multicenter, randomized, controlled trial.

OBJECTIVES: The purpose of this study was to compare the clinical effectiveness in reducing large overjet between a prefabricated functional appliance (PFA) and a slightly modified Andresen activator (AA). SETTING AND SAMPLE POPULATION: Public Dental Service, Gothenburg, Sweden. PARTICIPANTS, STUDY DESIGN, AND METHODS: A multicentre, prospective randomized clinical trial was conducted with patients from 12 general dental practices. One hundred and five patients with an Angle Class II, division 1 malocclusion and an overjet of ≥6mm were eligible for the study. Eight patients were excluded due to various reasons and the sample consisted thus of 97 subjects (44 girls, 53 boys) with a mean age of 10.3 years. The study was designed as intention to treat and the patients were randomly allocated by lottery to treatment with either a PFA or an AA. The PFA and AA group consisted of 57 subjects (28 girls, 29 boys) and 40 subjects (16 girls, 24 boys), respectively. Overjet, overbite, lip seal, and sagittal molar relationship were recorded before, at the end of treatment and 1-year post-treatment. Blinding was not performed. The endpoint of treatment was set to overjet ≤3mm and after this a 6 months retention period followed. RESULTS: No significant difference was found in overjet, overbite, sagittal relation, and lip seal between the two groups for the total observation period. The treatment of 40 (70 per cent) patients with PFA and 21 (53 per cent) with AA were considered unsuccessful mainly due to poor compliance. LIMITATIONS: No cephalometric records were taken as only patient-centred clinical outcome were used as an indicator for treatment success. The criteria of reduction of overjet to as low as 3mm could have affected the success rate. CONCLUSION: No difference in effectiveness could be shown between PFAs and AAs in correcting overjet, overbite, sagittal molar relation, and lip seal. The success rate in treatment with both appliances is, however, low. REGISTRATION: This trial was registered in "FoU i Sverige" (http://www.fou.nu/is/sverige), registration number: 97131. PROTOCOL: The protocol was not published before trial commencement.

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

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.

Orthodontic tooth movement into edentulous ridge areas--a case series.

The aim of this case series was to analyse dimensional alterations of the alveolar ridge and tooth-supporting structures, as well as root resorption, following orthodontic tooth movement into edentulous areas with reduced ridge dimensions. The study involved six subjects (30-70 years) with 10 edentulous jaw areas in the premolar regions. Clinical and radiographic examinations and 3D measurements on scanned study casts were performed at baseline, at retention, and after 1 year of (i) the edentulous area into which the tooth was moved and (ii) the established edentulous area from which the tooth was moved. The orthodontic tooth movement into an edentulous area resulted in most individuals in only minor dimensional alterations of the periodontal tissues. With regard to the width of the alveolar process, the results indicated a decreased width in the newly established edentulous area, whereas in the area into which the tooth had been moved, the width increased. In all cases, the moved tooth showed lateral root resorption on its pressure side at the level of the bone crest at time of retention, but signs of repair were noticed at the 1-year follow-up. Within the limitations of the study, it can be concluded that orthodontic tooth movement results in dimensional alterations of the edentulous ridge and that lateral root resorption is an inevitable side-effect.

Molar position associated with a missing opposed and/or adjacent tooth: a follow up study in women.

UNLABELLED: The purpose of the study was to assess (i) the degree of overeruption of molars lacking opposed teeth and (ii) the inclination of molars with a mesial edentulous space and alsoto study (iii) changes during a 12 year period. The subject sample originated from the prospective population study of women in Gothenburg, Sweden where scanned panoramic radiographs taken with an interval of 12 years were analysed. Tipping as well as overeruption were scored on the two images according to a five-level scale. Sixty-seven subjects fulfilled the inclusion criteria at baseline and were referred to as "the non-extraction group". Further 35 subjects had lost the opposed and/or the adjacent tooth/teeth during the 12-year follow-up period: "the extraction-group". These groups were studied separately and a comparison between these groups was performed. The prevalence of molars tipped more than 15 degrees at baseline was 17.1% in the upper jaw and 44.3 % in the lower jaw, in the non-extraction group. At baseline overeruption was seen in 25 % of the unopposed upper molars and none of lower molars in the non-extraction group. The prevalence of tipping and overeruption was statistical significant less in the extraction group (P<0.01), than in the non-extraction group at baseline, but at follow-up no statistical significant group differences existed. IN CONCLUSION: The prevalence of tipped molars facing a mesial edentulous space and overerupted unopposed molars increased in adults during the 12-year period but the changes were small. Overeruption and tipping is most pronounced immediately after extractions.

Frequency of errors and pathology in panoramic images of young orthodontic patients.

The aims of this study were to evaluate the frequency of errors in panoramic radiographs in young orthodontic patients, to register pathologic and abnormal conditions, and to compare these findings with the patient's record. A total of 1287 panoramic radiographs of children and adolescents (530 boys and 757 girls; mean age 14.2 years) were analyzed. The radiographs were obtained of patients referred for orthodontic treatment during a 1 year period. Four observers evaluated the radiographs for 10 common errors, pathologies, and/or anomalies. Cohen's kappa was used for the calculations of inter- and intraobserver variability. Five of the errors were divided into clinically relevant or not clinically relevant errors, i.e. errors influencing diagnosis. Only those pathological findings with a possible influence on orthodontic treatment were compared with the patient's record. Of the 1287 radiographs, 96 per cent had errors. The number of errors in each image varied between 1 and 5, and in 24 per cent of these images, the errors could be of importance for clinical decision making. The most common error was that the tongue was not in contact with the hard palate. Pathologies or anomalies were found in 558 patients and a total of 1221 findings were recorded. Findings of possible relevance for orthodontic treatment were 63, and 12 of those were registered in the patient records. Pathological findings outside the dental arches were low and could be an argument for minimizing the radiation field.

The Effects of Loaded Plyometric Exercise during Warm-Up on Subsequent Sprint Performance in Collegiate Track Athletes: A Randomized Trial.

Prior evidence demonstrates the efficacy by which plyometric activities during warm-up conditions augment the subsequent performance in power-centric exercise. We investigated the acute effects of loaded jump squats incorporated into a standard sprinters' warm-up protocol on subsequent sprint performance in collegiate track athletes. Sprint times of 22 male and female collegiate track athletes were measured in 10-m intervals during a 30-m sprint trial following a standard sprinters' warm-up routine with or without plyometric exercise. Subjects were tested on two separate occasions, once with loaded jump squats as the experimental treatment (two sets of eight jumps, load = 13% bodyweight) (PLYO) and once with time-equated rest as the control treatment (CON). Treatments were implemented following a standard sprinters' warm-up routine familiar to the subjects. A dependent T-test was used for comparison of sprint interval times between conditions with a significant effect indicated by a p-value < 0.05. Sprint time did not differ between CON vs. PLYO at the 10 m (PLYO = 1.90 ± 0.12 s vs. CON = 1.90 ± 0.11 s, p = 0.66), 20 m (PLYO = 3.16 ± 0.21 s vs. CON = 3.15 ± 0.19 s, p = 0.53), and 30 m (PLYO = 4.32 ± 0.32 s vs. CON = 4.31 ± 0.28 s, p = 0.61) intervals. There was no interaction between treatment and sex, sex-specific ranking (above vs. below sex-specific mean), or sprint event (short vs. short-long vs. long) for 10 m, 20 m, or 30-m interval sprint times. At least within the limits of the current investigation, no evidence was provided to suggest that jump squats loaded at 13% bodyweight are an effective means to acutely potentiate sprint performance in collegiate track athletes. However, a further examination of responders indicates that the present loaded jump squat protocol may preferentially potentiate sprint performance in faster male athletes.

Management of root resorption in a large orthodontic clinic.

The aim of this study was to investigate, describe and analyse how the problem of root resorption is handled in a large orthodontic clinic and if these approaches were in accordance with the recommendations and guidelines described in the literature, and to estimate the prevalence of root resorption found in the radiographic material. All records of patients who terminated active treatment with fixed or removable appliances during the year 2004 at the Department of Orthodontics, University Clinics of Odontology, Göteborg, Sweden were examined (902 patients). In 837 records adequate information was obtained. The factors studied included: the presence of journal recordings of predisposing factors, the presence of radiographic examinations before, during and after treatment, the frequency of radiographic examinations and the prevalence of moderate or severe root resorption reported. The most frequent registrations were for trauma, and nail biting. Before treatment 81.5% of the patients were examined with periapical radiographs. After 6 months of treatment the percentage was 54.5%, while 15.8% of the patients were examined twelve months after treatment. At the end of treatment 52.5% of the patients were examined. When moderate root resorption was diagnosed during treatment the use of lower forces, resting periods and decrease of the treatment duration were the most common preventive measures. The prevalence of light root resorption was 1.9%, 3.2%, 4.9% and 8.6% at the beginning, after 6 and 12 months and at the end of treatment, respectively. Severe root resorption was found in 1.9% at the end of treatment. In conclusion before treatment periapical radiographs were taken in most cases. The percentage of the radiographs dropped significantly at 6 and 12 months. At the end of treatment half of the patients were examined with periapical radiographs.When moderate root resorption was diagnosed the use of lower forces, resting periods and decrease of treatment time were common preventive measures. Light root resorption was found in less than 10% while severe root resorption was noted in 2% after active treatment.

Diagnosis, screening and treatment of root resorption in orthodontic practices in Greece and Sweden.

OBJECTIVE: To evaluate the perception of Greek and Swedish orthodontic practitioners regarding the possible occurrence and prognosis of root resorption occurring during orthodontic treatment and to estimate practitioners' approaches to the diagnosis of preexisting root resorption, screening of prevalence, and treatment planning approach when moderate or severe root resorption is present. MATERIALS AND METHODS: Questionnaires were received from randomly selected Greek (n = 90) and Swedish (n = 106) practitioners. Topics of the questions included (a) the presence of history; (b) the radiographic evaluation of root resorption before, during, and after treatment; (c) the treatment approach of initial prevention and protocols in cases of radiographic diagnosis of root resorption during treatment. RESULTS: Of the respondents, 47.1% of the Swedish practitioners and 32.3% of the Greek practitioners use periapical and panoramic radiographs to diagnose root resorption, mostly in the anterior region. Both groups recognize trauma, root form, and oral habits as predisposing factors. The majority of Swedish orthodontists perform radiographic follow-up in the first 6 months. In contrast, the Greek orthodontists perform it at 1 year or at the end of treatment. The treatment approach for root resorption that is most frequently used by Swedish orthodontists is altering the treatment plan, using light forces, and allowing resting periods, while the Greek orthodontists most frequently use lighter forces and reduce the total duration of the treatment. CONCLUSIONS: Because there is no specific approach offered in the literature, the prevention and treatment reassessment in cases of root resorption relies on individual practitioner perception.

von Langenbeck procedures at 8 months or Wardill at 18 months for primary repair of cleft palate in adult Swedish patients with unilateral complete cleft lip and palate: a study of facial growth.

The purpose of this study was to compare facial growth in patients with unilateral complete cleft lip and palate (UCLP) in whom the palate was repaired with the von Langenbeck procedure at 8 months (L-8), or the Wardill procedure at 18 months (W-18). A total of 151 unaffected subjects were used as a reference series. Sixty-one adult patients, 34 in the L-8 group and 27 in the W-18 group, were investigated clinically and with lateral skull radiography and also filled out a questionnaire about their dental condition. Multiple linear regression was used to analyse the effects of the surgical strategy, sex, and the presence of a velopharyngeal flap on several dependent variables indicating sagittal jaw relations, vertical jaw relations, and inclination of incisors. The UCLP group was characterised by a short (n-sp) and retrusive maxilla (s-n-ss) and a retrusive mandible for women (s-n-sm), larger maxillary inclination (NSL/NL), more retroclined lower incisors (IL(I)/ML), shorter upper facial heights (n-sp) and normal total face height (n-gn) than the reference group. In the UCLP group there were significant differences between men and women in mandibular prognathism (s-n-sm), maxillary/mandibular relations (ss-n-sm), maxillary inclination (NSL/NL), total anterior facial height (n-gn), and upper anterior facial height (n-sp). Lateral crossbite was found in 20% of the UCLP group. The prevalence was similar in the L-8 and W-18 groups. Almost 80% of the patients in the UCLP group considered that their dental condition was good. The choice of surgical strategy had no significant influence on the variables measured on facial morphology.

A long-term follow-up study of Class II malocclusion correction after treatment with Class II elastics or fixed functional appliances.

INTRODUCTION: The aim of this study was to compare dentofacial morphology and long-term follow-up changes in growing males with skeletal Class II malocclusions treated without extractions and with either Begg or Herbst appliances. METHODS: Lateral cephalograms were obtained at the start of treatment, after active treatment, and after long-term follow-up. RESULTS: Treatment effects differed between the groups, with usually more favorable effects in the Herbst group. However, during the follow-up period, many of the changes were reversed. During the total observation period, maxillary prognathism and lower anterior facial height increased more in the Begg group than in the Herbst group. CONCLUSIONS: Although there were initial marked differences in the treatment outcomes, most of these differences were not sustained over the longer term.

TMD in relation to malocclusion and orthodontic treatment.

OBJECTIVE: The aim of this systematic literature review was to evaluate associations between different malocclusions, orthodontic treatment, and signs and symptoms of temporomandibular disorders (TMD). MATERIALS AND METHODS: This review was part of a project at the Swedish Council on Technology Assessment in Health Care focusing on malocclusion and orthodontic treatment from a health perspective. As a first step, the literature was searched in the Medline and Cochrane Library databases from 1966 to May 2003. A later update was made in January 2005. Human studies in English or in Scandinavian languages were included. RESULTS: Associations between certain malocclusions and TMD were found in some studies, whereas the majority of the reviewed articles failed to identify significant and clinically important associations. TMD could not be correlated to any specific type of malocclusion, and there was no support for the belief that orthodontic treatment may cause TMD. Obvious individual variations in signs and symptoms of TMD over time according to some longitudinal studies further emphasized the difficulty in establishing malocclusion as a significant risk factor for TMD. A considerable reduction in signs and symptoms of TMD between the teenage period and young adulthood has been shown in some recent longitudinal studies. CONCLUSIONS: Associations between specific types of malocclusions and development of significant signs and symptoms of TMD could not be verified. There is still a need for longitudinal studies.

Long-term stability of orthodontic treatment and patient satisfaction. A systematic review.

OBJECTIVE: To evaluate morphologic stability and patient satisfaction at least 5 years after orthodontic treatment. MATERIALS AND METHODS: Published literature was searched through the PubMed and Cochrane Library electronic databases from 1966 to January 2005. The search was performed by an information specialist at the Swedish Council on Technology Assessment in Health Care. The inclusion criteria consisted of a follow-up period of at least 5 years postretention; randomized clinical trials, prospective or retrospective clinical controlled studies, and cohort studies; and orthodontic treatment including fixed or removable appliances, selective grinding, or extractions. Two reviewers extracted the data independently and also assessed the quality of the studies. RESULTS: The search strategy resulted in 1004 abstracts or full-text articles, of which 38 met the inclusion criteria. Treatment of crowding resulted in successful dental alignment. However, the mandibular arch length and width gradually decreased, and crowding of the lower anterior teeth reoccurred postretention. This condition was unpredictable at the individual level (limited evidence). Treatment of Angle Class II division 1 malocclusion with Herbst appliance normalized the occlusion. Relapse occurred but could not be predicted at the individual level (limited evidence). The scientific evidence was insufficient for conclusions on treatment of cross-bite, Angle Class III, open bite, and various other malocclusions as well as on patient satisfaction in a long-term perspective. CONCLUSIONS: This review has exposed the difficulties in drawing meaningful evidence-based conclusions often because of the inherent problems of retrospective and uncontrolled study design.

A comparative study of cone beam computed tomography and conventional radiography in diagnosing the extent of root resorptions.

BACKGROUND: Root resorptions are assessed and diagnosed using different radiographical techniques. A comparison of the ability to assess resorptions on two-dimensional (2D) and three-dimensional (3D) radiographs is, hitherto, lacking. The aims of this study were to evaluate the accuracy of 2D (periapical radiographs, PA and panoramic radiograph, PAN) and 3D (cone beam computed tomography, CBCT) radiographic techniques in measuring slanted root resorptions compared to the true resorptions, a histological gold standard, in addition to a comparison of all the radiographic techniques to each other. METHODS: Radiographs (CBCT, PA, and PAN), in addition to histological sections, of extracted deciduous canines from thirty-four patients were analyzed. Linear measurements of the most and least resorbed side of the root, i.e., "slanted" resorptions, were measured using an analyzing software (Facad ®). For classification of slanted root resorptions, a modified Malmgren index was used. RESULTS: PAN underestimated the root length on both the least and most resorbed side. Small resorptions, i.e., low modified Malmgren scores, were more difficult to record and were only assessed accurately using CBCT. The root resorption scores were underestimated using PA and PAN. In assessment of linear measures, PAN differed significantly from both CBCT and PA. CONCLUSIONS: CBCT is the most accurate technique when measuring and scoring slanted root resorptions.

The mechanism of Class II correction in surgical orthodontic treatment of adult Class II, division 1 malocclusions.

The purpose of this investigation was to assess the dentoskeletal effects and facial profile changes as well as the mechanism of Class II correction in adult Class II subjects treated by surgical mandibular advancement in combination with orthodontics. The subject material comprised 46 adults with a Class II, division 1 malocclusion treated by nonextraction with a mandibular sagittal split osteotomy as well as with pre- and postsurgical multibracket appliances. Lateral head films from before treatment and after treatment were analyzed. The results revealed the following statistically significant (P < .001) treatment changes: (1) the mandibular prognathism enhanced; (2) the sagittal interjaw base relationship improved; (3) the mandibular plane angle increased; (4) the lower anterior facial height increased; (5) the lower posterior facial height decreased; (6) the facial profile straightened; (7) the overjet and Class II molar relationship were corrected. Overjet reduction was accomplished by 63% skeletal and 37% dental changes. The Class II molar correction was accomplished by 81% skeletal 19% dental changes. In conclusion, it can be said that mandibular sagittal split osteotomy in combination with pre- and postsurgical orthodontics is an effective and consistent method for the correction of Class II, division 1 malocclusions and for the straightening of the facial profile. A negative effect of treatment counteracting Class II correction is an increase in the mandibular plane angle.