Why WITS? Why not a way beyond?
BACKGROUND
WITS appraisal is a common parameter in cephalometrics to assess maxillo-mandibular skeletal relationship as an adjunct to angle ANB. The high variability of the WITS appraisal is attributable to difficulties or inaccuracies in identifying the occlusal plane or variations due to tooth eruption, dental development or treatment changes by vertical movement of incisors, molars, or both.


OBJECTIVE
An extracranial reference line common to both denture bases, instead of the occlusal plane is proposed to assess antero-posterior jaw relationships.


METHODS
A true vertical obtained by plumb line was recorded, while taking the cephalogram for 40 subjects. A line drawn perpendicular to this true vertical gave a stable and reproducible extracranial true horizontal (HOR) reference line. The linear distance between perpendiculars from points A and B was measured as an adjunct to angle ANB.


RESULTS
The Pearson's product moment correlation coefficient calculated for the entire sample indicated higher correlation coefficient (r = 0.8712) for the linear measurements on HOR (AH-BH) with respect to the angle ANB when compared with the WITS readings (AO-BO) (r = 0.549).


CONCLUSIONS
The horizontal appraisal method proposed eliminates the demerits of the occlusal plane and has the merits of simplicity and accuracy in comparison to WITS appraisal.
Department of Orthodontics and Dentofacial Orthopaedics, Inderprastha Dental College, Ghaziabad, India.
Shipra
S
Nagar
Department of Conservative Dentistry and Endodontics, Kalka Dental College, Meerut, Uttar Pradesh, India.
Rohit
R
Nagar
Department of Orthodontics and Dentofacial Orthopaedics, Subharti Dental College, Meerut, Uttar Pradesh, India.
Pradeep
P
Raghav
Antero-posterior jaw relationship; Johannesburg; South Africa appraisal; Witwatersrand university; cephalometrics; cephalostat; extracranial reference line; occlusal plane; true horizontal