title: Comparison of hard tissue interrelationships at the cervical region of teeth based on tooth type and gender difference.
abstract: BACKGROUND
  Cementoenamel junction (CEJ) represents the anatomic limit between the crown and root surface. With advancing age and continuous eruption, this area becomes exposed in the oral media. Consequently, CEJ will be subjected to the action of various physical and chemical factors that might alter its morphology, with the cementum being affected in most cases.
  
  
  OBJECTIVE
  To identify the frequency of hard tissue interrelationships present at the CEJ in relation to different genders, positions and aspects of tooth using a light microscope.
  
  
  METHODS
  The cervical regions of 80 permanent teeth (40 male and 40 female), extracted for orthodontic or periodontal reasons, were analyzed after longitudinal ground sections were made in the mesio-distal plane. The CEJ of the prepared sections was then studied and their frequencies were categorized as: cementum overlapping enamel, enamel overlapping cementum, edge-to-edge relationship and the presence of gap junctions.
  
  
  METHODS
  Chi-square test performed using SPSS 15 software.
  
  
  RESULTS
  Edge-to-edge contact of the cementum and enamel was most frequent, followed by gap junction and cementum overlapping the enamel, respectively. Chi-square test revealed no statistically significant differences with respect to the gender and tooth aspect, whereas the result was significant when the position of the tooth was studied.
  
  
  CONCLUSIONS
  The observations of the study indicate a considerable morphological diversity in the anatomical pattern of CEJ. It can be concluded that the region should be protected against dentinal sensitivity, erosion, abrasion, abfraction and resorption, as it is more prone to cervical pathologies.
authors.affiliation: Department of Oral and Maxillofacial Pathology, Pacific Dental College and Hospital, Udaipur, Rajasthan, India.
authors.forename: Madhusudan
authors.initials: M
authors.lastname: Astekar
authors.affiliation: Department of Oral and Maxillofacial Pathology, Darshan Dental College and Hospital, Udaipur, Rajasthan, India.
authors.forename: Prabhpreet
authors.initials: P
authors.lastname: Kaur
authors.affiliation: Department of Oral and Maxillofacial Pathology, Pacific Dental College and Hospital, Udaipur, Rajasthan, India.
authors.forename: Nidhi
authors.initials: N
authors.lastname: Dhakar
authors.affiliation: Department of Conservative Dentistry and Endodontics, Army Dental Corps, Chandimandir (WC), Panchkula, India.
authors.forename: Jappreet
authors.initials: J
authors.lastname: Singh
keywords: Cementoenamel junction; dental cementum; light microscopy; permanent dentition; tooth cervix; tooth components