Composite lateral cephalometric norms– A pooled estimate of 137 Indian studies

The aim was to derive pooled mean for the commonly used lateral cephalometric parameters for populations belonging to different regions of the country and to compare the derived norms between them. Electronic databases such as Google, Google Scholar, Medline (via PubMed), and Scopus were searched for studies deriving regional lateral cephalometric norms. Grey literature search and hand search were also performed. An online survey was conducted among orthodontists to identify the most commonly used cephalometric parameters.137 studies were included from a total of 9693 records. The studies retrieved were grouped according to region of study as South, North, Central and West, and North-East. A total of 44 parameters were finalised for which the pooled mean and SD were estimated. The values differed significantly between different populations for most skeletal and dental parameters. The South Indians were found to have more prognathic maxilla (M= 82.74±2.07, F= 82.80±2.05) and mandible (M= 80.36±2.01, F= 79.94±1.93) compared to North Indians (SNA: M= 81.68±4.71, F= 81.15±3.26; SNB: M= 79.40±4.30, F= 78.76±3.39). The ANB angle was found to be the least in the Central and West Indians (M= 1.91±2.07, F= 2.06±1.95). The South Indians also showed increased upper incisor inclination (Upper 1 to NA: M= 27.46±4.2, F= 27.41±6.16), while it was least in the North Indians (M= 21.59, F= 23.73).This was a novel attempt to derive pooled mean for the commonly used cephalometric parameters for the Indian population, which can serve as a reference for clinicians and researchers alike.