double male syndrome  is a rare sex chromosome aneuploidy condition characterized by presence of two extra x and y chromosomes with an incidence of 1:18,000 - 1:40,000 male births . this syndrome is clinically manifested later in life with developmental delays , learning disabilities , behavioral problems , and delayed or incomplete puberty . many cases go undiagnosed as most of the above mentioned abnormalities do not develop until early puberty . the term taurodontism was coined by sir arthur kein to describe the bull - like appearance of the teeth . taurodontism can be defined as a morphological variation of a tooth in which the pulp chamber is vertically elongated and the roots are reduced in size . the etiology of taurodontism is attributed to the failure of hertwig epithelial root sheath diaphragm to invaginate at the proper horizontal level . based on the severity , taurodontic teeth can be classified ashypo- , meso- , and hypertaurodont forms . hypotaurodont expresses the least pronounced changes , while mesotaurodont expresses moderate variation , and hypertaurodont is characterized by the most severe variation in which the roots bifurcate or trifurcate close to the apices . this is the first reported incidence of the endodontic management of a hypertaurodontic mandibular molar tooth in a patient diagnosed with 48 , xxyy syndrome . a 19-year - old male reported to the postgraduate department of endodontics of our dental school , for management of multiple carious teeth . during history taking , it was elicited that the patient was a school dropout due to difficulty in coping with the educational curriculum . it was also evident , that the patient had below average communication skills with low self - esteem . ( b and c ) postsurgical photograph after bilateral sagittal split osteotomy and genioplasty intraoral examination revealed dental caries in relation to teeth 15 , 37 , and 47 and multiple missing teeth ( 14 , 13 , 22 , 23 , and 36 ) . an orthopantomograph revealed multiple taurodontic teeth in relation to 37 , 46 , 47 , 17 , 26 , and 27 [ figure 2a ] . the taurodontic teeth exhibited large pulp chamber extending beyond the cervical area and reaching the furcation suggestive of hypertaurodontism . the tooth was nonsensitive to percussion , and radiographic interpretation was suggestive of asymptomatic apical periodontitis . ( c ) a 2-year follow - up post endodontic restoration in 37 the complete endodontic management of the case was performed by one of the author , while the other author took care of post - endodontic restoration and clinical follow - up with department of oral surgery . the patient was anesthetized with 1.7 ml of 4% articaine with 1:100,000 epinephrine ( septocaine , septodont , new castle , de , usa ) and access opening was performed under rubber dam isolation . endodontic treatment in taurodontic teeth has been described as difficult as the complex morphology could hamper the location of the root canal orifices . the access opening and canal tracing was performed with the help of adental operating microscope ( g6 , global microscope , usa ) . careful inspection and exploration revealed a large coronal pulp chamber extending 8 - 10 mm below the cervical margin ( cementoenamel junction ( cej ) ) . the presence of two canals ( mesial and distal ) bifurcating 3 - 4 mm short of the radiographic apex was identified . an electronic apex locator ( root zx , morita , tokyo japan ) was used to determine the working length . the shaping and cleaning of all canals was done using nickel - titanium rotary instruments , k3 ( sybron endo , orange , ca , usa ) . irrigation was done with 5.2% sodium hypochlorite solution ( naocl ) during shaping and cleaning of the root canal system . passive ultrasonic irrigation ( pui ) activation was employed using # 20/0.00 taper ss noncutting ultrasonic tip ( irrisafe , satelec , acteon , merignae , france ) followed by 1 min flush of 17% ethylenediaminetetraacetic acid ( edta ; smearclear , sybronendo , ca , usa ) . the canals were dried using sterile paper points and dressed with intracanal calcium hydroxide medicament and the tooth was sealed temporarily with an intermediate restorative material ( cavitg , 3m - espe , seefeld , germany ) . the patient was asked to return after 2 weeks . at the second appointment , copious irrigation was done in order to remove the calcium hydroxide and the canals were made dry with sterile paper points . following radiographic control of the fit of gutta - percha mastercone ( guttapercha , sybronendo , ca , usa ) , the apical part of the main root canals was obturated with vertically compacted warm gutta - percha using the touch&heat 5004 device ( sybron endo , ca , usa ) . the coronal portion of the main canal was backfilled with thermoplasticized gutta - percha using the obtura iigun ( obtura - spartan corp , fenton , mo , usa ) . the access cavity was sealed with dualcuredcomposite resin ( paracore , coltene / whaledent , nj , usa ) . the patient was then referred to the department of oral surgery for surgical correction of prognathic mandible . the first stage involved a bilateral sagittal split osteotomy followed after 3 months by a second stage surgical advancement genioplasty procedure . follow - up was at 6-months and 2-year intervals [ ure 1b and c ] . a normal individual has 22 pairs of autosomes ( numbered chromosomes ) and one pair of autosomes and a single x and y chromosome , making a karyotype or chromosomal makeup of 46 , xy . similarly , a normal female has 22 pairs of autosomes and two x chromosomes , making a karyotype 46 , xx . 48 , xxyy syndrome is characterized by an extra x chromosome and an extra y chromosome . this , in addition to the 22 pairs of autosomes , males with 48 , xxyy syndrome has four sex chromosomes , making a karyotype 48 , xxyy . successive meiotic nondisjuctional events during spermatogenesis , resulting in a xyy sperm have been attributed as the most probable etiological mechanism of 48 , xxyy syndrome . the presence of extra sex chromosomes may lead to altered deoxyribonucleic acid ( dna ) methylation at various loci in genome leading to altered gene expression and subsequent phenotype variation . according to gardner and girgis , a patient with multiple taurodontic teeth without known association of any systemic syndrome should be consulted for chromosomal analysis , as there is a higher association of taurodontic teeth with x - chromosome aneuploidy syndromes . hence , we referred our patient to the department of human genetics for chromosomal analysis . chromosome analysis with gtg banding with a resolution of 450 - 550 bp , showed a numerical abnormality in all cells analyzed , with the presence of an extra x and an extra y chromosome resulting in 48 chromosomes and a diagnosis of 48 , xxyy syndrome was made [ figure 3 ] . chromosome analysis with gtg banding showing numerical abnormality in all cells with presence of extra x and y chromosome the prevalence of taurodontism ranges from 2.5 to 11.3% of the human population . taurodontism can occur either as an isolated manifestation or in association with various systemic syndromes . a literature search for relevant articles regarding endodontic management of taurodontic tooth associated with systemic syndromes was performed using ovid medline , cochrane database of systemic reviews , embase , and pubmed . table 1 summarizes the chronological order of case reports of taurodontism associated with systemic syndromes . chronological reports of systemic syndromes associated with taurodontism this case showing 48 , xxyy karyotype is recognized as a distinct clinical and genetic entity . this syndrome was previously considered to be a variant of klinefelter syndrome ( 47 , xxy ) ; however , it is now considered to be a distinct phenotype with more significant cognitive and psychological impairments . the characteristic differences between these two syndromes have been well documented by tartaglia et al . comparison of 47 , xxy klienfelter syndrome and 48 , xxyy syndrome ( adapted from tartaglia et al . , 48 , xxyy , 48 , xxxy , and 49 , xxxxy syndromes : not just variants of klinefelter syndrome , acta paediatr : 2011 ; 100(6):851 - 860 ) knowledge regarding 48 , xxyy syndrome and its dentofacial manifestations is important for early diagnosis and long - term predictable medical and dental health management . an early recognition of such a disorder is crucial in improving the psychological as well a dental quality of life in affected patients .
taurodontism is a developmental anomaly of a tooth characterized by large pulp chamber and short roots . 
 patients with multiple taurodontic teeth are associated with the probability of a systemic syndrome or chromosomal anomaly . 
 this is the first reported incidence of the endodontic management of a hyper taurodontic mandibular second molar in a patient diagnosed with 48 , xxyy syndrome .