angle classified malocclusion in the sagittal plane based on the dental relationship and ignoring the skeletal relation .
the disto - occlusion is categorized into division 1 and division 2 based on the spatial orientation of upper anterior teeth . apart from these basic features
, there were no characteristic features pertaining to class ii div 2 in the literature .
the class ii div 2 malocclusion is rare and procuring the study sample is always a difficult task .
even though angle gave the classification of malocclusion in 1890s , there is still lack of clarity regarding the classical features of class ii div 2 malocclusion .
moorrees et al . , buschang et al . , and walkow and peck analyzed the study models of class ii div 1 and div 2 and summarized that class ii div 2 malocclusion exhibited decreased intercanine width .
assessed the cephalometric parameters between these two groups and found that mandibular retrognathism was a similar feature in both the groups . in the current scenario ,
an orthodontist should be abreast with the classical appearance of a malocclusion , as this may help the professional to choose the best treatment possible for the patient .
the aim of this study is to differentiate the cephalometric and transverse arch dimensions between angle 's class ii div 1 and div 2 malocclusions , in order to understand the diagnostic features of class ii div 2 malocclusion .
the diagnostic study casts and the lateral cephalometric radiographs required for the study were obtained from the hospital records of drs sudha and nageswara rao siddhartha institute of dental sciences .
a total of 612 pre - treatment records were obtained , with age ranging from 14 to 25 years ; of these , 317 were class ii div 1 and 295 were class ii div 2 malocclusions .
the inclusion criteria were angle 's class ii molar relationship on both the sides , with all the permanent teeth erupted , and an increased horizontal and vertical overlapping greater than 5 mm and 4 mm , respectively , for class ii div 1 malocclusion and overjet of 3 mm and 100% overbite for class ii div 2 malocclusion .
the transverse arch width dimensions were measured by using digital vernier calipers ( parameters used are explained in figures ) .
an appropriate statistical test was used to assess the cephalometric variables and transverse arch dimensions between the study groups .
intragroup evaluation was done at first to rule out sexual difference within the study groups . after the final verification that the sex did not have a variable difference
, males and females in either of the study group were combined to evaluate the cephalometric and transverse arch dimensions . the vertical linear variables and dental variables on the cephalometric radiograph
[ figures 14 and table 1 ] revealed a notable variation ( jarabak ratio , lower facial third and down 's mandibular plane angle ) .
skeletal sagittal parameters skeletal vertical parameters  angular skeletal vertical parameters  linear dental and soft tissue parameters mean comparison of cephalometric parameters between class ii div 1 and class ii div 2 groups the maxillary transverse arch dimensions [ figure 5 and table 2 ] were comparatively more in angle 's class ii div 2 group of malocclusion . a notable difference was not found with respect to the mandibular arch width parameters [ figure 6 and table 2 ] .
( a ) maxillary intercanine width ( b ) basal arch width at maxillary canines ( c ) maxillary intermolar width ( d ) basal arch width at maxillary molars mean comparison of arch width parameters between class ii div 1 and class ii div 2 groups mandibular arch width parameters .
( a ) mandibular intercanine width ( b ) basal arch width at mandibular canines ( c ) mandibular intermolar width ( d ) basal arch width at mandibular canines
in 1950s , studies were conducted in the department of orthodontics , university of illinois to evaluate the dental features and skeletal arrangement among various malocclusions .
vallera and nelson reported that analyzing cephalometric radiograph helps the orthodontist to arrive at treatment planning .
reported that the transverse arch dimensions and the apical bases , too , have a diagnostic potential .
hence , we have evaluated both cephalometric and transverse arch dimensions in the present study .
the sna , snb , and anb angles were measured in both the groups because of their importance in orthodontic diagnosis . to analyze the position and spatial orientation of bony bases , certain important parameters from mcnamara analysis and schwartz analysis
the dental parameters included in the study were orientation of upper incisor with sella - nasion plane ( ui - sn plane ) and lower incisor to mandibular plane ( go - me ) .
facial angle , skeletal convexity , h - line angle , and lower lip to ricketts e - line were included as a part of the study .
both the groups were shown to have class ii skeletal bases with a mild retrognathic mandible .
these results were in accordance with pancherz et al . and isik et al . and contrasted with rosenblum , demisch et al .
the skeletal vertical parameters [ figures 2 and 3 ] showed a clear hypodivergent growth pattern with decreased lower facial thirds in class ii div 2 group of malocclusion [ table 1 ] .
the maxillary anterior teeth were absolutely retroclined in the class ii div 2 group , as per angle 's abbreviation of class ii div 2 malocclusion .
lower anteriors were near normal without much difference between both the groups [ table 1 ] .
there was no significant difference between the two study groups with respect to the soft tissue measurements except for the linear measurement of lower lip to ricketts e - line .
the lower lip was slightly behind the ricketts e - line in class ii div 2 group .
this might be the reason for prominent chin , deep mentolabial sulcus , and poor retention ( excessive pressure exerted by lower lip on the upper anteriors ) .
the maxillary arch width parameters [ figure 5 and table 2 ] were increased with a statistically significant difference in class ii div 2 group of malocclusion .
these results educate the orthodontist to choose for non - extraction mode of therapy , unless the patient 's soft tissue integument demands for extraction .
as there is normal or increased maxillary arch width and narrowing of mandibular arch width , there is more probability for the occurrence of malalignment in the lower arch in class ii div 2 group .
the main setback of the study is that we have focused only on the lateral cephalograms and study models , not considering the clinical examination .
the study had focused only on the local population and , therefore , some results may be contradicting with the world 's averages .
the sna , snb , and anb angles were measured in both the groups because of their importance in orthodontic diagnosis . to analyze the position and spatial orientation of bony bases , certain important parameters from mcnamara analysis and schwartz analysis
the dental parameters included in the study were orientation of upper incisor with sella - nasion plane ( ui - sn plane ) and lower incisor to mandibular plane ( go - me ) .
facial angle , skeletal convexity , h - line angle , and lower lip to ricketts e - line were included as a part of the study .
both the groups were shown to have class ii skeletal bases with a mild retrognathic mandible .
these results were in accordance with pancherz et al . and isik et al . and contrasted with rosenblum , demisch et al . , and peck et al
the skeletal vertical parameters [ figures 2 and 3 ] showed a clear hypodivergent growth pattern with decreased lower facial thirds in class ii div 2 group of malocclusion [ table 1 ] .
this is in accordance with houston , bjork and skeiller , pancherz et al . , karlsen , and peck et al .
the anticlockwise rotation in class ii div 2 malocclusion may be because of lack of incisor support .
the maxillary anterior teeth were absolutely retroclined in the class ii div 2 group , as per angle 's abbreviation of class ii div 2 malocclusion .
lower anteriors were near normal without much difference between both the groups [ table 1 ] .
there was no significant difference between the two study groups with respect to the soft tissue measurements except for the linear measurement of lower lip to ricketts e - line .
the lower lip was slightly behind the ricketts e - line in class ii div 2 group .
this might be the reason for prominent chin , deep mentolabial sulcus , and poor retention ( excessive pressure exerted by lower lip on the upper anteriors ) .
the maxillary arch width parameters [ figure 5 and table 2 ] were increased with a statistically significant difference in class ii div 2 group of malocclusion .
the results of the present study were similar to buschang et al . , staley et al . , and sayin and turkkahraman .
these results educate the orthodontist to choose for non - extraction mode of therapy , unless the patient 's soft tissue integument demands for extraction .
as there is normal or increased maxillary arch width and narrowing of mandibular arch width , there is more probability for the occurrence of malalignment in the lower arch in class ii div 2 group .
nowadays the treatment plan is mainly based on the soft tissue integument of the patient .
the main setback of the study is that we have focused only on the lateral cephalograms and study models , not considering the clinical examination .
the study had focused only on the local population and , therefore , some results may be contradicting with the world 's averages .
the classical features of angle 's class ii div 2 group of malocclusion were as follows : 
 orthognathic maxilla and a mild retrognathic mandiblemarked horizontal growth pattern with forwardly rotated mandibular baseskeletal deep biteretroclined upper incisors with near - normal lower anteriorslower lip placed slightly behind e - line with prominent chinincreased transverse maxillary values ( intercanine and intermolar widths ; basal arch width at canines and molars)restricted mandibular arch width , hence , increased chances for crowding in lower arch . 
 
orthognathic maxilla and a mild retrognathic mandible marked horizontal growth pattern with forwardly rotated mandibular base retroclined upper incisors with near - normal lower anteriors lower lip placed slightly behind e - line with prominent chin increased transverse maxillary values ( intercanine and intermolar widths ; basal arch width at canines and molars ) restricted mandibular arch width , hence , increased chances for crowding in lower arch .
 statement of problem : a thorough knowledge of the salient features of malocclusion makes the practitioner to come to a proper diagnosis and to formulate proper mechanotherapy . it also helps to predict the prognosis , prior to the onset of treatment process . among the various malocclusions , class ii div 2 occurs the least often . the literature review does not clearly describe the classical skeletal and dental features of angle 's class ii div 2 malocclusion.purpose of study : the aim of this study is to describe the unique features of angle 's class ii division 2 malocclusion.materials and methods : a total of 612 pre - treatment records ( study models and cephalograms ) , with age ranging from 14 to 25 years , were obtained from the hospital records of drs sudha and nageswar rao siddhartha institute of dental sciences . among these samples , 317 were class ii div 1 and 295 were class ii div 2 . 
 the lateral cephalograms were analyzed by using kodak software and the arch width analysis was calculated by using digital vernier calipers.results:student's t test was used for the study . on the cephalograms , the vertical skeletal measurements and few of the dental variables showed a significant difference . on the plaster models , 
 the maxillary transverse measurements revealed a notable discrimination between the groups.conclusion:angle's class ii div 2 malocclusion has a marked horizontal growth pattern with decreased lower facial thirds , palatally inclined upper anteriors , and remarkably increased transverse maxillary arch dimensions . 
INTRODUCTION
MATERIALS AND METHODS
RESULTS
DISCUSSION
Cephalometric parameters
Limitations
CONCLUSION
Financial support and sponsorship
Conflicts of interest