The maxillary sinus is connected to the nose and therefore fluid can come out of the nostrils when drinking· Change in sounds produced from the nose and the voice – specifically a whistling sound whilst speaking· Taste can be affected

Signs
· Visible hole between mouth and sinus
· Fracture of the floor of the maxillary sinus creating a communication to the oral cavity (e.g. as seen following trauma).· Air bubbles, blood or mucoid secretion around the orifice can be seen as air passes from the sinus into the oral cavity through the communication. Diagnosis
- Patient history - Diagnosis is usually based on clinical examination and reported symptoms. Therefore, a good history and understanding of the patient’s symptoms is key. - Undertake a complete extraoral and intraoral examination using a dental mirror alongside good lighting. When assessing the socket following an extraction look for granulation tissue in the socket which may represent normal healing. Assess for the presence of visible an opening/hole between the oral cavity and the maxillary sinus. - Imaging can be useful. However, radiographs only show if there is a breach in the bony floor of the antrum. Even if there is a breach in the bony floor then the Schneiderian membrane may still be intact. Depending on the size of the potential communication and in what context, a small radiograph inside the mouth may be sufficient (a periapical) to assess for any break in the bone of the sinus floor which may indicate an OAC.
A Bakers cyst, also known as a popliteal cyst, is a type of fluid collection behind the knee. Often there are no symptoms. If symptoms do occur these may include swelling and pain behind the knee, or knee stiffness. If the cyst breaks open, pain may significantly increase with swelling of the calf. Rarely complications such as deep vein thrombosis, peripheral neuropathy, ischemia, or compartment syndrome may occur.Risk factors include other knee problems such as osteoarthritis, meniscal tears, or rheumatoid arthritis. The underlying mechanism involves the flow of synovial fluid from the knee joint to the gastrocnemio-semimembranosus bursa, resulting in its expansion. The diagnosis may be confirmed with ultrasound or magnetic resonance imaging (MRI).Treatment is initially with supportive care. If this is not effective aspiration and steroid injection or surgical removal may be carried out. Around 20% of people have a Bakers cyst. They occur most commonly in those 35 to 70 years old. It is named after the surgeon who first described it, William Morrant Baker (1838–1896). Signs and symptoms
Symptoms may include swelling behind the knee, stiffness, and pain. If the cyst breaks open, pain may increase, and there may be swelling of the calf. Rupture of a Bakers cyst may also cause bruising below the medial malleolus of the ankle (Crescent sign). Cause
In adults, Bakers cysts usually arise from almost any form of knee arthritis (e.g., rheumatoid arthritis) or cartilage (particularly a meniscus) tear. Bakers cysts in children do not point to underlying joint disease.