Cephalograms taken in the Natural Head Position (NHP), and related to the true vertical and the true horizontal reference planes should logically replace the planes used in conventional cephalometry. This has not happened because of the difficulties in radiographically recording the NHP. This paper presents a modified approach to capture the true vertical reference line on the patients' face itself in NHP, which is then transferred to the conventional lateral cephalogram.

Twists in rectangular archwires may be used only when reciprocal torque is needed on adjacent teeth. In other situations, alternative torquing methods should be considered.

No abstract

Biomechanical influences on bone structure play an important role in the longevity of bone around an implant. The quantity and direction of applied force influence the implant and cause deformation of the bone. FEA was used to analyze the changes in the bone on loading the implant with orthodontic force in oblique and vertical directions and orthopedic force. The Mini-implants used in the present study efficiently resisted the oblique loading. But their use, for the purpose of orthopedic loading is questionable. FE models showed the area with the highest stress and strain to be around the neck of the implant and the surrounding bone at the cervical margin.

Objective:To check the reliability of various study model indices viz Ponts', Bolton's, Howes', Peck and Peck Index and Korkhaus Index. Materials and methods:Study models of male and female subjects between the age range of 18 and 26 years with normal Class I occlusion and an overjet or overbite < 3 mm and a crowding or spacing of < 2 mm were selected. Index values calculated were subjected to statistical comparison with earlier studies.