private void button3_Click(object sender, EventArgs e)
 {
     OldPatientForm ob = new OldPatientForm();
     ob.Show();
 }
 private void openToolStripMenuItem2_Click(object sender, EventArgs e)
 {
     OldPatientForm ob = new OldPatientForm();
     ob.Show();
 }
 private void treatmentBtn_Click(object sender, EventArgs e)
 {
     OldPatientForm ob = new OldPatientForm();
     ob.Show();
     this.Close();
 }