Hi Pradeep Enugala,
Buttons' height is increased to 22px. in order to fit and look better when placed next to RadInput or RadComboBox items. The previous button height was 21px. If you are using a custom skin, based on previous version, you should change your main skin's CSS as shown in this sticky forum thread.
If you need help to change the styles and size of the buttons, please send a solution with Button Sprites included and we will fix it.
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