The palatine rugae do not extend posteriorly beyond the anterior half of the hard palate and never cross the midline.
The shape, length, width, prominence, number and orientation of palatine rugae vary considerably among people.
Van der Linden  evaluated changes in the position of posterior teeth in relation to palatine rugae in 65 normally growing children (aged 6 to 16 years) and in six orthodontically treated patients.
Tooth movement: Hoggan and Sadowsky  investigated the use of the palatine rugae as reference points for measuring tooth movement in a manner comparable with cephalometric superimpositions.
Palatine rugae in cleft palate: Park and colleagues  studied the pattern of palatine rugae in submucosal clefts.
In a second study, Kratzsch and Opitz  investigated the relationship of palatine rugae to points (landmarks) and distances on the cleft palate during the period from birth to the time of early mixed dentition.
Kashima (1990)  compared the palatine rugae and shape of the hard palate in Japanese and Indian children.
Japanese children had more primary rugae than Indian children, but both groups had the same number of transverse palatine rugae.
Both groups had many transverse palatine rugae on the left side of the palate.
Shetty and colleagues (2005)28 compared the palatine rugae patterns in Indians with those in a Tibetan population.