diff --git a/src/components/dialog/dialog.js b/src/components/dialog/dialog.js
index ad42aa11512..02e746a0a0d 100644
--- a/src/components/dialog/dialog.js
+++ b/src/components/dialog/dialog.js
@@ -699,7 +699,7 @@ function MdDialogProvider($$interimElementProvider) {
       transformToClickElement(dialogEl, options.origin);
 
       $$rAF(function () {
-        dialogEl.addClass('transition-in')
+        dialogEl.addClass('md-transition-in')
           .css($mdConstant.CSS.TRANSFORM, '');
       });
 
@@ -712,7 +712,7 @@ function MdDialogProvider($$interimElementProvider) {
     function dialogPopOut(container, options) {
       var dialogEl = container.find('md-dialog');
 
-      dialogEl.addClass('transition-out').removeClass('transition-in');
+      dialogEl.addClass('md-transition-out').removeClass('md-transition-in');
       transformToClickElement(dialogEl, options.origin);
 
       return $mdUtil.transitionEndPromise(dialogEl);
diff --git a/src/components/dialog/dialog.scss b/src/components/dialog/dialog.scss
index 451370fcc3c..cfec8f7810c 100644
--- a/src/components/dialog/dialog.scss
+++ b/src/components/dialog/dialog.scss
@@ -16,12 +16,12 @@ $dialog-padding: $baseline-grid * 3;
 }
 
 md-dialog {
-  &.transition-in {
+  &.md-transition-in {
     opacity: 1;
     transition: $swift-ease-out;
     transform: translate3d(0,0,0) scale(1.0);
   }
-  &.transition-out {
+  &.md-transition-out {
     transition: $swift-ease-out;
     transform: translate3d(0,100%,0) scale(0.2);
   }