diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..1fde4cf
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,41 @@
+pub enum NotationKind {
+    Iso,
+    Palmer,
+    Uns,
+    Alphanumeric,
+}
+
+pub enum TeethKind {
+    Canine,
+    Incisor,
+    Premolar,
+    Molar,
+}
+#[derive(PartialEq, Clone, Copy)]
+pub enum QuadrantKind {
+    TopLeft,
+    TopRight,
+    BottomLeft,
+    BottomRight,
+}
+
+pub struct Teeth {
+    quadrant: QuadrantKind,
+    number: u8,
+    permanent: bool,
+}
+
+impl Teeth {
+    pub fn new(number: u8, quadrant: QuadrantKind, permanent: bool) -> Teeth {
+        if !permanent && number > 5 {
+            panic!("Primary tooth number are in range [1; 5]");
+        }
+
+        Teeth {
+            number,
+            quadrant,
+            permanent,
+        }
+    }
+
+}
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..639a6f8
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,4 @@
+mod display;
+mod lib;
+fn main() {
+}