Soft tissue treatment changes with fixed functional appliances and with maxillary premolar extraction in Class II division 1 malocclusion patients

The aim of this study was to compare the soft tissue changes and post-treatment status after complete fixed functional appliance non-extraction and maxillary premolar extraction treatment in patients with Class II division 1 malocclusion.



The sample consisted of 96 lateral cephalograms of 48 patients, divided into two groups. Group 1 consisted of 23 patients treated with fixed functional appliance associated with fixed appliances, with initial and final mean ages of 12.71 and 15.16 years, respectively, mean treatment time of 2.44 years and initial mean overjet of 6.83 mm. Group 2 comprised 25 patients treated with extraction of two maxillary premolars with initial and final mean ages of 13.05 and 15.74 years, respectively, mean treatment time of 2.67 years and initial mean overjet of 7.01 mm. t-Tests were used to compare treatment changes and the final cephalometric statuses between the groups.



According to the results, there was no inter-group difference regarding the soft tissue changes and post-treatment status.



The use of exclusively one type of fixed functional appliance in group 1 and performance of only one type of mechanics during space closure in group 2 were not always possible.



Late pubertal patients with Class II division 1 malocclusion treated with fixed functional appliances associated with fixed appliances present similar soft tissue results as two-maxillary premolar extraction treatments.

Related papers:

title: Effects of orthodontics on the facial profile: a comparison of changes during nonextraction and four premolar extraction treatment.
abstract: Cephalometric radiographs were used to examine soft tissue profiles of 198 orthodontic patients treated with full fixed appliances without extraction of any permanent teeth. Records were selected at random from five sources: cases treated by a Tweed Foundation instructor using the Tweed technique, patients treated with the Begg appliance, patients treated in one of two different practices with pretorqued, preangulated edgewise appliances, and patients treated in two stages with a functional appliance followed by full fixed edgewise appliances. The criteria for selection of cases and the methods of data collection were designed to allow comparisons with data collected by Drobocky and Smith on patients treated with extraction of four first premolars. Although the mean value of soft tissue changes were smaller in the nonextraction patients, the variability of these changes were generally as great as in the four premolar extraction cases. In addition, the percentage of undesirable facial changes was similar in the extraction and nonextraction samples. The results provide additional evidence that it is simplistic and incorrect to blame undesirable facial esthetics after orthodontic treatment on the extraction of premolars.

title: The influence of extraction versus non-extraction orthodontic treatment on the soft tissue profile.
abstract: The aim of the present study was to study profile changes following orthodontic harmonization of enlarged overjet and to attempt to trace predictive aspects regarding prognosis of the soft tissue changes. Lateral cephalograms and study models of 40 female patients, at least 12 years old at the start of treatment, with an overjet of > or = 6 mm were analyzed before (T1) and after treatment (T2). Twenty patients were treated without extractions, while in the remaining 20 patients extractions of premolars were carried out bilaterally in both jaws. The 2 groups were found to be highly homogeneous as regards overjet, cephalometric characteristics, space condition in the upper arch at T1 and both at T1 and T2 as regards age. The most striking aspect of the findings was the considerable amount of variability of the soft tissue changes. These changes were found to be rather unpredictable for the individual patient, since the regression models employed could give only a very wide individual prediction range. The relatively small changes registered, using superimposition methods, in both groups as regards the sagittal position of the lips in comparison to the very strong changes observed in relation to the esthetic line shows that the influence of the growth of the chin and/or the nose on the facial profile might be more important than the influence of the orthodontic treatment. The interpretation of the findings in the present study suggests that, apart from marked cases of skeletal convexity or concavity, the extraction versus non-extraction decision should be based primarily upon current knowledge of long-term stability of orthodontic treatment results.

title: Facial changes in extraction and nonextraction patients.
abstract: The purpose of this study was to determine if there are any differences in the posttreatment faces of patients treated nonextraction and those treated with premolar extraction in properly diagnosed and treated cases. The study was conducted in two parts. In Part 1, perceptions of 192 experienced general dentists and orthodontists were tested. Facial photos of 25 consecutively treated nonextraction patients and 25 consecutively treated four-premolar-extraction patients were shown to the study participants. They were asked if the patient was treated with the extraction of four premolars or without extractions. The mean score of the respondents was 54%, only slightly better than pure chance. In Part 2, profiles were evaluated based on cephalometric tracings. There was no significant difference between pretreatment and posttreatment profiles of the groups. The mean H-line values for both groups were within the desired esthetic range. It was concluded that experienced orthodontists and general dentists could not determine whether treatment was nonextraction or extraction by looking at the face alone. Also, there was no significant difference between the faces produced by the two types of treatments. Therefore, the avoidance of extracting premolars based on a fear of a significant detrimental effect on the face is unjustified when the case has been properly diagnosed and treated.

title: Esthetic impact of premolar extraction and nonextraction treatments on Korean borderline patients.
abstract: The esthetic impact of the soft-tissue profile might play a major role in deciding on premolar extraction or nonextraction treatment, particularly in borderline patients. The purpose of this study was to compare the esthetic impact of extraction and nonextraction therapy on Korean patients.



Panels of 50 dentists and 50 laypersons evaluated randomly presented pretreatment and posttreatment soft-tissue profiles of 50 extraction and 50 nonextraction patients. As subjects in this study, borderline patients were selected based on their initial diagnostic records. Two panels were asked to compare the pretreatment and posttreatment profile tracings and to quantify their perceptions of the esthetic impact of treatment change using a visual analog scale.



Premolar extraction patients showed greater improvement in facial profile compared with nonextraction patients, regardless of the panel. Based on the results of regression analysis to determine the degree of lip protrusion at which the retraction that commonly follows premolar extraction would be needed, the intersection was about 3.0 mm behind the Ricketts' E-line; this is far behind the Korean norm.



The results indicate that premolar extraction is more beneficial than nonextraction treatment in terms of facial profile improvement in Korean borderline patients.

title: Changes in soft tissue profile after orthodontic treatment with and without extractions.
abstract: The effects of orthodontic treatment on the facial profile, with or without the extraction of teeth, have greatly concerned orthodontists. A study was made of 80 patients with Angle Class I malocclusion. Forty patients (24 girls, 16 boys) did not undergo extraction of teeth, and 40 patients (23 girls, 17 boys) underwent extraction of maxillary and mandibular first premolars. Data were obtained from the corresponding lateral radiographs of the head taken before and after orthodontic treatment. The purpose of this study was to compare the response of the soft tissue of the facial profile in Class I malocclusions treated with and without the extraction of the 4 first premolars. The main soft tissue differences between the groups at the end of treatment were more retruded upper and lower lips in the extraction patients.

title: Treatment and posttreatment changes in patients with Class II, Division 1 malocclusion after extraction and nonextraction treatment.
abstract: The purpose of this study was to evaluate the treatment and posttreatment changes in the facial and dental parameters in two groups of patients with Class II, Division 1 malocclusions. In one group (n = 46), the patients were treated with a nonextraction approach, whereas in the second group (n = 45), the treatment included the extraction of four first premolars. The treatment groups were compared with matched untreated normals (n = 35) from the Iowa Growth Study. Lateral cephalograms and dental casts were evaluated at three stages: pretreatment, posttreatment, and approximately 2 years after treatment. Student's t tests were used to compare the extraction and nonextraction groups. Significance was predetermined at p < or = 0.05. The cephalometric findings indicate that before treatment, the subjects treated with four first premolar extractions had more protrusive upper and lower lips and a larger tooth size-arch length discrepancy. After treatment the upper and lower lips were more retrusive in the extraction groups, and more protrusive in the nonextraction groups. The extraction groups tended to have straighter faces and slightly more upright maxillary and mandibular incisors, whereas the nonextraction groups had the opposite tendencies. The average soft tissue and skeletal measurements for both groups were close to, but on opposite sides of, the corresponding averages derived from the Iowa normative standards. The findings from the dental arch measurements indicate that after treatment both the extraction and nonextraction groups experienced an increase in tooth size-arch length discrepancy and a reduction in arch length. In general, extractions did not significantly alter the direction of the overall posttreatment trends. Furthermore, the trends in the posttreatment changes were similar in male and female patients, as well as in the maxillary and mandibular arches. The current findings suggest that the extraction/nonextraction decision, if based on sound diagnostic criteria, does not have a systematic detrimental effect on the facial profile. But clinicians should be aware of the trends introduced by the two treatment modalities to avoid accentuating undesirable profile characteristics.

title: Long-term profile changes associated with successfully treated extraction and nonextraction Class II Division 1 malocclusions.
abstract: This study was undertaken to compare the post-treatment and long-term soft tissue profiles of successfully managed and stable Class II, division 1 malocclusions treated with either 4 first premolar extractions or nonextraction therapy. It was hypothesized that, if sound extraction decisions were made according to accepted treatment objectives and successful treatment outcomes were achieved, there should be no differences between groups in soft tissue profiles post-treatment and long-term post-retention. The sample consisted of 63 Caucasian adolescents (23 extraction, 40 nonextraction). Correction of the malocclusion was achieved using a combination of cervical headgear concurrent with mandibular growth and maxillary incisor retraction. Pretreatment, post-treatment, and long-term post-retention lateral cephalometric radiographs were evaluated. The soft tissue facial profiles of the extraction and nonextraction samples were the same following active treatment and long-term post-retention. Progressive flattening of the facial profile was observed in both samples. This flattening was attributed to the maturational changes associated with continued mandibular growth and nasal development and was not influenced by whether or not teeth were removed. Long-term lip positions were more retrusive than the ideals suggested by Ricketts and Steiner, but close to the values reported for normal, untreated adults of similar ages. The pretreatment position and thickness of the lower lip as well as the initial maxillomandibular skeletal relationship may be predictors of post-treatment or long-term lower lip position.

title: Profile changes of patients treated with and without premolar extractions.
abstract: In this study, we evaluated and compared treatment effects and long-term soft-tissue profile changes in patients treated with extraction of 4 first premolars and with a nonextraction protocol.



Cephalometric records of 98 patients were evaluated. For half (n = 49) of the patients, treatment included the extraction of 4 first premolars; the other 49 patients had no premolar extractions. The groups were evaluated before treatment (T1), at the end of treatment (T2), and at least 4 years postretention (T3).



At T1, the extraction group had more protrusive lower lips than the nonextraction group, as measured by the Z-angle. At T2, the Z-angles had improved in both groups and were not significantly different. During treatment, upper lip vermilion and superior thicknesses increased, whereas lower lip vermilion thickness decreased in both groups. Except for lower lip inferior thickness, which increased significantly in the nonextraction group, no other soft-tissue differences were significant. Significant growth of the nose occurred during from T1 to T2 in both groups, and there was a tendency for the incisors in both groups to return to pretreatment values. The nose also continued to grow during that period.



Overall, the soft-tissue facial profile measurements for both extraction and nonextraction samples were similar at T3, and there were no clinically significant correlations between hard- and soft-tissue variables at T1, T2, and T3.

title: Soft-tissue treatment changes in Class II Division 1 malocclusion with and without extraction of maxillary premolars.
abstract: In this study, we compared the soft-tissue changes and posttreatment status after nonextraction and maxillary premolar extraction treatment in patients with Class II Division 1 malocclusion.



Lateral cephalograms of 44 patients, divided into 2 matching groups, were evaluated. Group 1 comprised 22 patients (10 boys, 12 girls) treated nonextraction with initial and final mean ages of 12.50 and 15.12 years, respectively, and a mean treatment time of 2.62 years. This group had an initial mean overjet of 7.97 mm. Group 2 consisted of 22 patients (10 boys, 12 girls) treated with extractions of 2 maxillary premolars with initial and final mean ages of 12.86 and 15.32 years, respectively. The mean treatment time was 2.46 years, and the initial mean overjet was 8.61 mm. Independent t tests were used to compare the initial and final cephalometric status and the treatment changes between the groups.



According to the results, only 1 soft-tissue variable showed a significant treatment change between the groups. However, at the posttreatment stage, there were no significant differences between the soft-tissue variables.



The protocol including extraction of 2 maxillary premolars provides similar soft-tissue results as nonextraction treatment of complete Class II malocclusion.

title: The Effect of Premolar Extractions on Incisor Position and Soft Tissue Profile in Patients with Class II, Division 1 Malocclusion*
abstract: The objective of this study was to establish whether and how premolar extraction affects the soft tissue profile and incisor inclination in patients with Angle Class II, Division 1 malocclusion. Our primary intention was to identify differences between patients who had four premolars extracted and those who had only two upper premolars removed during camouflage treatment. Our control group consisted of patients with an Angle Class II, Division 1 treated without extractions.These patients’ lateral cephalograms were cephalometrically analyzed before and after treatment. Computer-assisted analysis of the data using Onyx Ceph® was followed by a single-factor variance analysis (one-way Our results demonstrate that patients who have undergone camouflage treatment exhibit significantly more retruded upper central incisors than those with extractions in both jaws, and that their upper incisors are highly significantly more retruded and their mandibles significantly more retrognathic than those of patients who have not undergone extraction therapy.We did not observe that the patients’ profiles did become worse after extraction therapy.Es soll dargestellt werden, ob und wie sich eine Prämolarenextraktion auf das Weichteilprofil und die Schneidezahnneigung bei Patienten mit Angle-Klasse II,1 auswirkt. Vor allem sollen Unterschiede zwischen Patienten, bei denen vier Prämolaren extrahiert wurden, und Patienten, denen im Rahmen einer Camouflage-Behandlung nur zwei Prämolaren im Oberkiefer entfernt wurden, ermittelt werden. Als Vergleichsgruppe dienen Patienten mit einer Angle-Klasse II,1, die ohne Extraktionen behandelt wurden.Die Fernröntgenseitenbilder dieser Patienten wurden vor und nach der Behandlung kephalometrisch ausgewertet. Im Anschluss an die computergestützte Auswertung der Daten mit Onyx Ceph® erfolgte eine einfaktorielle Varianzanalyse (Oneway ANOVA).Ergebnisse:Die Ergebnisse zeigen, dass Patienten mit Camouflage-Behandlung nach Therapie signifikant retrudierter stehende obere mittlere Schneidezähne als Patienten mit Extraktionen in beiden Kiefern haben und dass sie höchst signifikant retrudierter stehende obere Schneidezähne sowie signifikant retrognather liegende Unterkiefer als Patienten ohne Extraktionstherapie aufweisen.Eine Profilverschlechterung nach Extraktionstherapie konnte nicht nachgewiesen werden.

title: Forsus Nitinol Flat Spring and Jasper Jumper corrections of Class II division 1 malocclusions.
abstract: To compare the effects of Forsus Nitinol Flat Spring (FNFS) and Jasper Jumper (JJ) in the correction of Class II division I malocclusions.



Our research was conducted on 48 adolescents, who had a normal or horizontal growth pattern and retrognathic mandible. The patients were divided into three equal groups randomly. First group was treated with FNFS, and the second group was treated with JJ appliances, whereas the third group was the control group. Lateral cephalograms and study models were obtained after the leveling phase and at time of the removal of the appliances.



Cephalometric analysis revealed that both the appliances stimulated mandibular growth, increased the anterior face height because of the lower face, and elongated the posterior face height because of the growth of temporomandibular joint. Maxillary central incisors were extruded, retruded, and distally tipped. Contrarily, intrusion, protrusion, and labial tipping were observed in the mandibular central incisors. Distal movement and intrusion of the maxillary first molars and mesial movement and extrusion of the mandibular first molars were the other dental alterations. Overjet and overbite were decreased, and a Class I molar relationship and improvement in the profile were attained in both treatment groups. Cast model analysis showed expansion in the maxillary and mandibular dental arches.



Both the appliances were effective in the treatment of Class II malocclusion and revealed nearly same alterations in the skeletal, dental, and soft tissue parameters.

title: Treatment effects of the mandibular anterior repositioning appliance in patients with Class II skeletal malocclusions.
abstract: To examine the changes produced by the mandibular anterior repositioning appliance (MARA) appliance and compare the treatment effects to an untreated Class II control group.



Thirty consecutively treated patients were matched with an untreated control group. Lateral cephalograms were taken at T1, 5 months pre-MARA (CVMS 2.7); T2, immediately after MARA removal and prior to placement of full fixed edgewise appliances (CVMS 4.2); and T3, at least 2 years after MARA removal and completion of edgewise treatment (CVMS 5.4). The mean age of the MARA patients was 11.9 years for boys and 10.8 years for girls. Repeated-measures analysis of variance (ANOVA) was used to assess if the samples were morphologically comparable at the outset and to test if there were significant differences between the groups for the various increments of change. Given a significant ANOVA, the source of the difference was explored via Tukey-Kramer tests.



Restriction of maxillary growth and no significant mandibular growth were observed with the MARA appliance. The Class II correction was obtained mainly by slight maxillary molar distalization and intrusion, in addition to mesial migration of the lower molars and flaring of the lower incisors. No vertical effect was observed with this appliance.



The MARA appliance was effective in the treatment of Class II malocclusions. Restriction of maxillary growth and dentoalveolar changes in the maxillary and mandibular arches were responsible for the correction of the Class II malocclusion. Significant mandibular growth did not contribute to this correction.

title: Angle Class II correction with MARA appliance.
abstract: To assess the effects produced by the MARA appliance in the treatment of Angle's Class II, division 1 malocclusion.



The sample consisted of 44 young patients divided into two groups: The MARA Group, with initial mean age of 11.99 years, treated with the MARA appliance for an average period of 1.11 years, and the Control Group, with initial mean age of 11.63 years, monitored for a mean period of 1.18 years with no treatment. Lateral cephalograms were used to compare the groups using cephalometric variables in the initial and final phases. For these comparisons, Student's t test was employed.



MARA appliance produced the following effects: Maxillary growth restriction, no change in mandibular development, improvement in maxillomandibular relationship, increased lower anterior facial height and counterclockwise rotation of the functional occlusal plane. In the upper arch, the incisors moved lingually and retruded, while the molars moved distally and tipped distally. In the lower arch, the incisors proclined and protruded, whereas the molars mesialized and tipped mesially. Finally, there was a significant reduction in overbite and overjet, with an obvious improvement in molar relationship.



It was concluded that the MARA appliance proved effective in correcting Angle's Class II, division 1 malocclusion while inducing skeletal changes and particularly dental changes.

title: Dentoskeletal changes induced by the Jasper jumper and the activator-headgear combination appliances followed by fixed orthodontic treatment.
abstract: The aim of this study was to compare the dentoskeletal changes of patients with Class II Division 1 malocclusion treated with either the Jasper jumper appliance or the activator-headgear combination, both associated with fixed appliances.



The sample comprised 72 subjects with Class II Division 1 malocclusion divided into 3 groups: group 1 included 25 subjects treated with fixed appliances and the force modules of the Jasper jumper at an initial mean age of 12.72 years, group 2 included 25 subjects treated with the activator-headgear combination followed by fixed appliances at an initial mean age of 11.07 years, and group 3 included 22 untreated subjects at an initial mean age of 12.67 years. Initial cephalometric characteristics and dentoskeletal changes were compared with analysis of variance.



Both experimental groups had similar dentoskeletal changes: restrictive effect on the maxilla, clockwise mandibular rotation and a slight increase in anterior face height, retrusion of the maxillary incisors, distalization of the maxillary molars, protrusion of the mandibular incisors, extrusion of the mandibular molars, and significant improvements of the maxillomandibular relationship, overjet, overbite, and the molar relationship.



The effects of the Jasper jumper and the activator-headgear combination followed by fixed orthodontic appliances were similar in Class II malocclusion treatment.

title: Treatment effects produced by the Twin-block appliance vs the Forsus Fatigue Resistant Device in growing Class II patients.
abstract: To compare the dentoskeletal changes produced by the Twin-block appliance (TB) followed by fixed appliances vs the Forsus Fatigue Resistant Device (FRD) in combination with fixed appliances in growing patients having Class II division 1 malocclusion.



Twenty-eight Class II patients (19 females and 9 males; mean age, 12.4 years) treated consecutively with the TB followed by fixed appliances were compared with a group of 36 patients (16 females and 20 males; mean age, 12.3 years) treated consecutively with the FRD in combination with fixed appliances and with a sample of 27 subjects having untreated Class II malocclusion (13 females and 14 males; mean age, 12.2 years). Mean observation interval was 2.3 years in all groups. Cephalometric changes were compared among the three groups by means of ANOVA and Tukey's post hoc tests.



The FRD produced a significant restraint of the maxilla compared with the TB and control samples (SNA, -1.1° and -1.8°, respectively). The TB sample exhibited significantly greater mandibular advancement and greater increments in total mandibular length than either the FRD or control groups (SNB, 1.9° and 1.5°, respectively; and Co-Gn, 2.0 mm and 3.4 mm, respectively). The FRD produced a significantly greater amount of proclination of the mandibular incisors than what occurred with the TB or the control samples (2.9° and 5.6°, respectively).



The TB appliance produced greater skeletal effects in terms of mandibular advancement and growth stimulation while the Forsus caused significant proclination of the mandibular incisors.

title: Treatment effects of fixed functional appliances alone or in combination with multibracket appliances: A systematic review and meta-analysis.
abstract: To assess skeletal and dentoalveolar effects of fixed functional appliances, alone or in combination with multibracket appliances (comprehensive treatment), on Class II malocclusion in pubertal and postpubertal patients.



Literature survey was conducted using the Medline, SCOPUS, LILACS, and SciELO databases and The Cochrane Library, and through a manual search. The studies retrieved had to have a matched untreated control group. No restrictions were set regarding the type of fixed appliance, treatment length, or to the cephalometric analysis used. Data extraction was mostly predefined at the protocol stage by two authors. Supplementary mandibular elongation was used for the meta-analysis.



Twelve articles qualified for the final analysis of which eight articles were on pubertal patients and four were on postpubertal patients. Overall supplementary total mandibular elongations as mean (95% confidence interval) were 1.95 mm (1.47 to 2.44) and 2.22 mm (1.63 to 2.82) among pubertal patients and -1.73 mm (-2.60 to -0.86) and 0.44 mm (-0.78 to 1.66) among postpubertal patients, for the functional and comprehensive treatments, respectively. For pubertal subjects, maxillary growth restraint was also reported. Nevertheless, skeletal effects alone would not account for the whole Class II correction even in pubertal subjects with dentoalveolar effects always present.



Fixed functional treatment is effective in treating Class II malocclusion with skeletal effects when performed during the pubertal growth phase, very few data are available on postpubertal patients.

title: Long-term dentoskeletal changes with the Bionator, Herbst, Twin Block, and MARA functional appliances.
abstract: To determine if the long-term dentoskeletal changes in patients treated with tooth-borne functional appliances were comparable to each other and to matched controls.



The experimental sample consisted of 80 consecutively treated patients who were equally divided into Bionator, Herbst, Twin Block, and mandibular anterior repositioning appliance (MARA) groups. The control group comprised 21 children with untreated skeletal Class II malocclusions. Lateral cephalograms were taken for the treated group at T1 (initial records), T2 (completion of functional therapy), and T3 (completion of fixed appliance therapy). A repeated measure analysis of variance (ANOVA) was used to assess the differences between and within groups. If ANOVA results were significant, Tukey-Kramer tests were used to determine where the significant differences occurred.



(1) Temporary restriction of maxillary growth was found in the MARA group (T2-T1). (2) SNB increased more with the Twin Block and Herbst groups when compared with the Bionator and MARA groups. (3) The occlusal plane significantly changed in the Herbst and Twin Block groups. (4) The Twin Block group expressed better control of the vertical dimension. (5) The overbite, overjet, and Wits appraisal decreased significantly with all of the appliances. (6) The Twin Block group had significant flaring of the lower incisors at the end of treatment. (7) Over the long-term, there were no significant soft tissue changes among treated and untreated subjects.



No significant dentoskeletal differences were observed long-term, among the various treatment groups and matched controls.

title: Effectiveness of early treatment of Class II malocclusion.
abstract: The purpose of this study was to examine and report the effectiveness of early treatment with the headgear/biteplate and the bionator in patients with Class II malocclusion regardless of the mechanism of correction and to compare early-treatment results with changes over a similar time period in an observation group. The role of factors such as compliance was examined to determine their contribution to effective treatment. The experimental design was a prospective, longitudinal, randomized controlled trial. At the end of the early-treatment period, all 3 groups differed significantly (overall, P = .001) in percentage of treatment goal achieved, with median values of 83% for the bionator group, 100% for the headgear group, and 14% for the observation group. In both treated and observation subjects, the percentages of goal achieved varied by initial molar class severity (treated, P =.0205; observation, P = .0040) and race (treated, P = .0314; observation, P = .0416). Significant correlations in the treated subjects were identified between percentage of goal achieved and bone age (13 bones) (r = 0.16; P = .037), bone age (20 bones) (r = 0.16; P = .043), compliance (r = 0.26; P = .0005), and initial overjet (r = -0.26; P = .0095). Significant correlations were not detected in the observation group. Sex, treatment group, age, mandibular plane angle, pretreatment, and retention did not significantly affect percentage of goal achieved among the treated and the observation subjects. Correlation between normalized compliance scores and percentage of goal achieved was high for both bionator (r = 0.50) and headgear subjects (r = 0.49) at the end of treatment. Multivariate analysis suggested that headgear may be superior to bionator/biteplane in achieving a Class II correction during early treatment.

title: The Cervical Vertebral Maturation (CVM) Method for the Assessment of Optimal Treatment Timing in Dentofacial Orthopedics
abstract: The present study introduces a further modified version of the Cervical Vertebral Maturation (CVM) method for the detection of the peak in mandibular growth, based on the analysis of the second through fourth cervical vertebrae in a single cephalogram. The morphology of the bodies of the second (C2 –odontoid process), third (C3), and fourth (C4) cervical vertebrae were analyzed in 6 consecutive cephalometric observations (T1 through T6) of 30 orthodontically untreated subjects. Observations for each subject consisted of two consecutive cephalograms comprising the interval of maximum mandibular growth (as assessed by means of the maximum increment in total mandibular length, Condylion –Gnathion: Co-Gn), together with two earlier consecutive cephalograms and two later consecutive cephalograms. The analysis consisted of both visual and cephalometric appraisals of morphological characteristics of the three cervical vertebrae. The construction of this new modified version of the CVM method was based on the results of both ANOVA for repeated measures with post hoc Scheffe’s test (P < 0.05) and discriminant analysis. The new clinically improved CVM method is comprised of six maturational stages (cervical stage 1 through cervical stage 6, ie, CS1 through CS6). CS1 and CS2 are prepeak stages; the peak in mandibular growth occurs between CS3 and CS4. CS6 is recorded at least 2 years after the peak. The use of the CVM method enables the clinician to identify optimal timing for the treatment of a series of dentoskeletal disharmonies in all three planes of space.

title: Interval estimation for Cohen's kappa as a measure of agreement.
abstract: Cohen's kappa statistic is a very well known measure of agreement between two raters with respect to a dichotomous outcome. Several expressions for its asymptotic variance have been derived and the normal approximation to its distribution has been used to construct confidence intervals. However, information on the accuracy of these normal-approximation confidence intervals is not comprehensive. Under the common correlation model for dichotomous data, we evaluate 95 per cent lower confidence bounds constructed using four asymptotic variance expressions. Exact computation, rather than simulation is employed. Specific conditions under which the use of asymptotic variance formulae is reasonable are determined.

title: Effects of the pendulum appliance, cervical headgear, and 2 premolar extractions followed by fixed appliances in patients with Class II malocclusion.
abstract: In this retrospective study, we compared the cephalometric effects, the dental-arch changes, and the efficiency of Class II treatment with the pendulum appliance, cervical headgear, or extraction of 2 maxillary premolars, all associated with fixed appliance therapy.



The sample of 82 patients with Class II malocclusion was divided into 3 groups: group 1 patients (n = 22; treatment time, 3.8 years) were treated with the pendulum appliance and fixed orthodontic appliances. Group 2 patients (n = 30; treatment time, 3.2 years) were treated with cervical headgear followed by fixed appliances; group 3 patients (n = 30; treatment time, 2.1 years) were treated with 2 maxillary premolar extractions and fixed appliances. The average starting ages of the groups ranged from 13.2 to 13.8 years. Data were obtained from serial cephalometric measurements and dental casts. The dental casts were analyzed with the treatment priority index. The treatment efficiency index was also used.



The 3 treatment protocols produced similar cephalometric effects, especially skeletally. Comparisons among the 2 distalizing appliances (pendulum and cervical headgear) and extraction of 2 maxillary premolars for Class II treatment showed changes primarily in the maxillary dentoalveolar component and dental relationships. The facial profile was similar after treatment, except for slightly more retrusion of the upper lip in the extraction patients. The treatment priority index demonstrated that occlusal outcomes also were similar among the groups. The treatment efficiency index had higher values for the extraction group.



The effects of treatment with the pendulum appliance or cervical headgear and extraction of 2 maxillary premolars associated with fixed appliances were similar from both occlusal and cephalometric standpoints. Class II treatment with extraction of maxillary teeth was more efficient because of the shorter treatment time. Differences in maxillary incisor retraction should be noted, but these differences might have been due to greater maxillary dentoalveolar protrusion in the extraction group before treatment.

title: Finishing occlusion in Class II or Class III molar relation: therapeutic Class II and III.
abstract: The most frequent extraction regime consists of the removal of upper and lower premolars. Depending on anchorage requirements, camouflage treatment options, surgical intervention, or the absence of teeth in only one arch, it may become necessary to finalize the occlusion with a one-dental-unit discrepancy between the upper and lower dental arches. Guidelines are presented for finishing occlusions in Class II or Class III molar relation.

title: Class II treatment efficiency in maxillary premolar extraction and nonextraction protocols.
abstract: In this study, we compared the efficiency of nonextraction and 2-maxillary-premolar-extraction protocols in complete Class II malocclusion treatment.



A sample of 112 records from patients with complete Class II malocclusion was divided into 2 groups with the following characteristics: group 1, comprising 43 patients treated nonextraction with an initial mean age of 12.63 years; and group 2, comprising 69 patients treated with extraction of 2 maxillary premolars with an initial mean age of 13.91 years. To compare the efficiency of each treatment protocol, the initial and final occlusal statuses were evaluated on dental casts with the peer assessment rating (PAR) index, and the treatment time of each group was calculated from the clinical charts. Treatment efficiency was calculated by the ratio between the percentage of PAR reduction and the treatment time. PAR scores, treatment times, and treatment protocols' efficiencies of the groups were compared with the t test.



The 2-maxillary-premolar-extraction protocol had a smaller final PAR score, a greater percentage of PAR reduction, and greater treatment efficiency than the nonextraction protocol of complete Class II malocclusion.



The 2-maxillary-premolar-extraction protocol has greater treatment efficiency than the nonextraction protocol of complete Class II malocclusion.

title: Smile esthetics: perception and comparison of treated and untreated smiles.
abstract: Although orthodontic treatment is based primarily on occlusal relationships, greater attention is now paid to enhancing dentofacial characteristics to produce optimal facial esthetics. The purposes of this study were to compare smile esthetics among extraction and nonextraction patients and a control group, assess certain dentofacial characteristics in those groups, and discuss how these features relate to smile esthetics.



Panels of orthodontists, plastic surgeons, artists, general dentists, dental professionals, and parents used a 5-point scale to rate smiling photographs of 25 extraction, 25 nonextraction, and 25 untreated control subjects. Dentofacial characteristics of the 3 groups were obtained from lateral cephalometric analyses, direct biometric measurements, and frontal photographs. Smile esthetics and differences among the 3 groups were subjected to 1-way analysis of variance (ANOVA), and Pearson correlation coefficients were calculated to determine the relationship of the variables to the esthetic score.



The mean esthetic scores for the extraction, nonextraction, and control groups were 3.15, 3.12, and 3.26, respectively. Visible dentition width relative to the smile width ratio and intercanine distance relative to smile width ratio were significantly different among the groups, with extraction patients showing a slightly wider dental arch relative to the soft tissue (P < .05). There was also a significant difference in the U1-SN angle among the groups (P < .05), and this variable showed a strong correlation with the esthetic score as did maxillary gingival display (P < .05). However, our study groups could not be differentiated in smile esthetics.

title: Smile attractiveness in patients with Class II division 1 subdivision malocclusions treated with different tooth extraction protocols.
abstract: The aim of this study was to compare smile attractiveness between one, three, and four premolar extraction protocols in patients with Class II division 1 subdivision malocclusions and to analyse the aesthetic influence of buccal and posterior corridor widths on smile attractiveness. The sample consisted of posed smile photographs obtained from 66 subjects, divided into three groups according to the treatment-extraction protocol. Group 1 was treated with one maxillary premolar extraction included 23 subjects, group 2 was treated with four premolar extractions included 23 subjects, and 20 patients in group 3 were treated with three premolar extractions. Buccal and posterior corridor widths of each photograph were measured in proportion to the smile width. To rate the posed smile photographs, panels of 70 orthodontists and 46 laypeople used a 10-point scale. There were no significant differences in smile attractiveness scores between the three groups and between orthodontists and laypeople. Also buccal and posterior corridor widths did not differ between the groups and they did not influence the aesthetic scores. It was concluded that smile attractiveness is similar in treatment protocols of one, three, and four premolar extractions and that widths of buccal and posterior corridors do not influence smile attractiveness in these groups.

title: Maxillary arch width and buccal corridor changes with orthodontic treatment. Part 2: attractiveness of the frontal facial smile in extraction and nonextraction outcomes.
abstract: This study was designed to assess the influence that the buccal corridor might have on the frontal facial attractiveness of subjects who had received orthodontic treatment with or without 4 premolar extractions.



Posttreatment full-face frontal smiling photographs of 30 premolar extraction and 27 nonextraction patients were evaluated by 20 orthodontists, 20 dentists, and 20 laypeople using a visual analog scale. The ratings were analyzed according to rater group, rater sex, and number of years in practice for orthodontists and dentists to search for any statistically significant differences in the ratings on the basis of treatment groups, subject sex, and buccal corridor widths and areas.



Orthodontists and dentists gave higher mean overall frontal facial attractiveness scores than did laypeople. There were no significant differences in how men and women rated the study subjects. The number of years in practice did not affect how the orthodontists rated, but it did affect the ratings of the dentists. Female subjects were consistently rated as significantly more attractive than male subjects. There was no difference in ratings for the extraction and nonextraction subject groups. The buccal corridor widths and areas did not affect the frontal facial attractiveness ratings.



If treatment has been carried out with thorough diagnosis and careful planning, neither the choice of extraction or nonextraction treatment, nor the resulting buccal corridor widths or areas appeared to affect the subjects' frontal facial attractiveness.

title: Esthetic perception of changes in facial profile resulting from orthodontic treatment with extraction of premolars: A systematic review.
abstract: The authors conducted a systematic review to assess changes in patients' facial profiles resulting from orthodontic treatment with and without extraction of 4 premolars and to identify cephalometric parameters that can assist decision making in borderline cases.


TYPES OF STUDIES REVIEWED
The authors conducted a systematic review of randomized clinical trials and observational studies comparing the 2 types of treatment (with and without premolar extraction) in terms of the changes in facial profile. The authors conducted an electronic search of the databases the Cochrane Library, PubMed MEDLINE, Embase, and Latin-American and Caribbean Health Sciences Literature.



The authors identified 1 clinical trial with 26 participants and 5 observational cohort studies, collectively involving 362 participants. The authors assessed cephalometric parameters and esthetic outcomes. Four studies used linear regression analysis to investigate esthetic interaction between treatment strategy and initial lower lip protrusion. The 4 studies determined that if the initial lip protrusion was beyond a determined point, esthetic preferences favored extraction, and if the initial lip protrusion was not to that point, esthetic preferences favored conservative treatment.



The results of the authors' systematic review found no significant differences between the groups in terms of the esthetic outcomes. The cephalometric parameter of initial lip protrusion can help with decision making in borderline cases.

title: Maxillary third molar position in Class II malocclusions: the effect of treatment with and without maxillary premolar extractions
abstract: There were more functioning third molars (M3s) in subjects treated with premolar extractions.

title: Prevalence of third molar impaction in orthodontic patients treated nonextraction and with extraction of 4 premolars.
abstract: The purposes of this study were to confirm that premolar extraction treatment is associated with mesial movement of the molars concomitant with an increase in the eruption space for the third molars and to test the hypothesis that such treatment reduces the frequency of third molar impaction. Lateral cephalograms, panoramic or periapical radiographs, and study models made before (T1) and after (T2) treatment and a minimum of 10 years postretention (T3) of 157 patients were selected from the postretention sample at the Department of Orthodontics of the University of Washington, Seattle. Treatment for 105 patients included the extraction of 4 premolars; the other 53 were treated nonextraction. These patients represented all the extraction and nonextraction patients in the sample who had at least 1 third molar at T1 or T2 and who showed evidence of full eruption or closure of the root apex at T2 or T3. Student t tests showed higher scores for third molar impaction (P <.01), less mesial movement of the molars from T1 to T2 (P <.01), and smaller retromolar space at T2 (P <.001) in both arches of the nonex patients than in the ex patients. Similarly, molar movement was more mesial from T1 to T2 in the maxilla (P <.01) and in the mandible (P <.05), and the retromolar space was larger in both arches (P <.001) of the patients with eruption than in those with impaction of the third molars. Our results suggest that premolar extraction therapy reduces the frequency of third molar impaction because of increased eruption space concomitant with mesial movement of the molars during space closure.

title: Treatment effects of fixed functional appliances in patients with Class II malocclusion: a systematic review and meta-analysis.
abstract: To assess the treatment effects of fixed functional appliances (FFAs) in treated versus untreated Class II patients by means of lateral cephalometric radiographs.



Unrestricted electronic search of 18 databases and additional manual searches up to October 2014.



Prospective randomized and non-randomized controlled trials reporting on cephalometric angular measurements of Class II patients treated with FFAs and their matched untreated controls.



Skeletal, dental, and soft tissue cephalometric data were annualized and stratified according to the time of evaluation in effects. Following risk of bias evaluation, the mean differences (MDs) and 95 % confidence intervals (CIs) were calculated with random-effects models. Patient- and appliance-related subgroup analyses and sensitivity analyses were performed with mixed-effects models.



Nine studies were included (244 patients; mean age: 13.5 years and 174 untreated controls; mean age: 12.8 years) reporting on cephalometric effects directly after the removal of FFAs. FFAs were found to induce a small reduction of SNA angle (MD = -0.83 degree/year, 95 % CI: -1.17 to -0.48), a small increase of SNB angle (MD = 0.87 degree/year, 95 % CI: 0.30-1.43), and moderate decrease of ANB angle (MD = -1.74 degree/year, 95 % CI: -2.50 to -0.98) compared to untreated Class II patients. FFA treatment resulted in significant dentoalveolar and soft tissue changes. Several patient- or appliance-related factors seem to affect the treatment outcome. Long-term effectiveness of FFAs could not be assessed due to limited evidence.



According to existing evidence, FFAs seem to be effective in improving Class II malocclusion in the short term, although their effects seem to be mainly dentoalveolar rather than skeletal.