Table of ContentsView AllTable of ContentsCausesSudden Lopsided SmileWhen to See a ProviderTreatmentFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
Causes
Sudden Lopsided Smile
When to See a Provider
Treatment
Frequently Asked Questions
A crooked or uneven smile is fairly common—most people do not have complete symmetry to their face. However, a crooked smile can mean there is a medical problem, and in some cases it can be an emergency. There are many possible reasons for a crooked smile, and most are not dangerous. However, a sudden change requires urgent medical attention.This article will discuss the possible meanings of a crooked smile, the significance of a sudden lopsided smile, and when to see a healthcare provider.Halfpoint Images / Getty ImagesLopsided Smile CausesA crooked smile can mean a variety of issues like dental problems, nerve damage, stroke, and more. Usually, the different causes are associated with additional symptoms besides a lopsided smile.StrokeA stroke is a serious type of brain damage that occurs due to an interrupted blood supply in an artery of the brain. Among othersymptoms, it can cause weakness of the face and body on one side.Symptoms from a stroke appear suddenly and it is a medical emergency. The acronym “FAST” stands forfacialdrooping,armweakness,speechdifficulties, andtimeto call emergency services.An Overview of StrokeBell’s PalsyThis type of facial weakness or paralysis affects one side of the face. Common symptoms affecting the mouth are that one corner of your mouth will droop and the smile line (nasolabial fold) will disappear.There will also be weakness in the forehead, eyelid, and cheek on that side of the face.Bell’s palsy develops over the course of a few hours and worsens for a few days. After a couple of weeks, it begins to improve gradually, often taking three to six months to get back to normal.The causes of Bell’s palsy are not known. It often improves on its own, and sometimes oral steroids can help speed up recovery.What Is Bell’s Palsy?Facial ParalysisFacial movements can become paralyzed (weak) due to nerve or muscle damage.Besides Bell’s palsy, stroke, and nerve injury, a few other causes of facial weakness include:Myasthenia gravis:A condition in which the immune system mistakenly attacks receptors needed to activate musclesMultiple sclerosis: A condition in which the immune system mistakenly attacks the protective myelin sheath of nerves in the brain, spinal cord, and eyesAmyotrophic lateral sclerosis: A disease that attacks the nerves that control movementUneven TeethMany people naturally have mildly or moderately uneven teeth. This typically does not cause a crooked smile. Sometimes teeth are naturally very uneven or become severely uneven due to dental conditions such as tooth decay. This can cause a smile to appear crooked.Misaligned JawThe jaw structure can cause a lopsided smile if the bones or movement of the jaw are formed unevenly or become damaged due to trauma or disease (such as cancer invading the bone).SurgerySurgery may cause damage to the nerve branches that control mouth movements. This can occur when surgery is necessary for removal of a tumor or abscess that has grown into thefacial nerve. And sometimes a surgical error can result in accidental transection (cutting) of a nerve or nerve branch.AgingFor some people, aging can lead to an uneven smile. This can occur as a result of wrinkles, dental issues, nerve damage, or stroke.SmokingSmoking may lead to mouth diseases, such as severe tooth decay, gum disease, or oral cancer. This can cause a crooked smile.TraumaAn injury to the face can cause damage to the nerves, muscles, bones, or other tissues. Swelling can be substantial as well. This can cause a lopsided smile and an uneven appearance of the face.After the swelling goes down and healing is complete, the face and smile can partially or fully return to normal. With severe trauma, a crooked smile can remain for the long term.TorticollisTorticollisis a movement disorder that causes involuntary (not on purpose) spasms and twisting of the neck. The muscles can spasm for prolonged periods, sometimes resulting in a crooked smile. This condition may be present from birth and can be associated with certain birth defects.Associated SymptomsSymptoms associated with a lopsided smile can include:Flattening of the nasolabial fold (the angled crease at the bottom of your cheeks, near your nose)Slurred speechTrouble chewing or swallowingAdroopy eyelidAn eyelid that can’t fully closeSudden Lopsided SmileA sudden lopsided smile can be a sign of a stroke,brain aneurysm(a bulge in the wall of an artery), or an infection. This may develop over the course of hours. Rarely, a new and rapidly worsening lopsided smile can be a sign of a tumor, cancermetastasis(spreading of cancer), or a seizure (uncontrolled electrical activity in the brain).What to Do if You Think Someone Is Having a StrokeIf you think someone is having a stroke, call 911 and stay with them until emergency help arrives. If possible, describe what you witnessed when emergency healthcare providers arrive.What to Do (and Not Do) If Someone Is Having a StrokeWhen to See a Healthcare ProviderIf your face or mouth suddenly feels numb or if movement seems uneven, you should get medical attention right away.Symptoms associated with an uneven smile that require urgent medical attention include:Sudden, severe headacheWeakness on one side of the bodyLoss of balanceVision changesFacial drooping on one sideSlurred speechTraumatic injurySwelling of the face or neckInability to control facial movementsSpasms of the face or neckPain in the eye or an infection of the eyeTreatmentThere are different techniques that can be used for treatment of an uneven smile. Immediate treatment differs from delayed treatment.During an emergency situation, such as a stroke or severe facial trauma, the immediate treatment involves preventing serious damage and reducing the long-term effects. This may include interventions such as blood thinners for stroke treatment or surgery for treatment of facial trauma.After a lopsided smile has stabilized, treatment can include exercises to train the muscles.This can be directed to improve the facial appearance, as well as to prevent complications, such as choking.In some situations, injections of Botox (botulinum toxin) can work to paralyze certain muscles to prevent a crooked appearance of the mouth.And sometimes surgical intervention may be necessary to reconstruct the facial nerves, muscles, bone, or other structures. This can help to even out the appearance of the face.This type of surgery may also be effective for reducing the risk of certain complications, like eye damage due to an eyelid that doesn’t properly close.SummaryA crooked smile can indicate many different medical problems. Sometimes, a person’s smile is uneven due to normal variations, and it isn’t usually anything to worry about. But a crooked smile can also mean there is a serious medical issue, such as a stroke or an infection.It’s important to get prompt medical attention for any sudden change in facial appearance. Other causes, such as Bell’s palsy or a misaligned jaw, may need medical intervention and management to prevent complications.Frequently Asked QuestionsGenerally, Bell’s palsy starts with stiffness or weakness of the face, including the eyelids. Blinking your eyes may feel uneven, or you might have a sensation of dryness in one of your eyes. Sometimes it can be hard to chew on one side, and your smile looks very uneven.The condition usually causes profound paralysis of one side of the face, including an inability to raise your eyebrow on one side. With Bell’s palsy, the face moves unevenly, and the sides of the face look uneven while you are resting your face.Learn MoreBell’s Palsy vs. StrokeYou should get medical attention if it is new, if it happens suddenly, or if the unevenness is severe. Complications can also be concerning, even if the cause is not dangerous.Complications may include corneal damage (to the outer layer of your eye), visual problems (due to a droopy eyelid), and the risk of choking due to chewing and swallowing problems.Common signs of a stroke include sudden weakness of one side of the face and/or body, trouble speaking or understanding language, loss of balance, dizziness, or confusion. Get prompt medical attention if you or someone else experiences these symptoms.
A crooked or uneven smile is fairly common—most people do not have complete symmetry to their face. However, a crooked smile can mean there is a medical problem, and in some cases it can be an emergency. There are many possible reasons for a crooked smile, and most are not dangerous. However, a sudden change requires urgent medical attention.
This article will discuss the possible meanings of a crooked smile, the significance of a sudden lopsided smile, and when to see a healthcare provider.
Halfpoint Images / Getty Images
Lopsided Smile Causes
A crooked smile can mean a variety of issues like dental problems, nerve damage, stroke, and more. Usually, the different causes are associated with additional symptoms besides a lopsided smile.
Stroke
A stroke is a serious type of brain damage that occurs due to an interrupted blood supply in an artery of the brain. Among othersymptoms, it can cause weakness of the face and body on one side.
Symptoms from a stroke appear suddenly and it is a medical emergency. The acronym “FAST” stands forfacialdrooping,armweakness,speechdifficulties, andtimeto call emergency services.
An Overview of Stroke
Bell’s Palsy
This type of facial weakness or paralysis affects one side of the face. Common symptoms affecting the mouth are that one corner of your mouth will droop and the smile line (nasolabial fold) will disappear.There will also be weakness in the forehead, eyelid, and cheek on that side of the face.
Bell’s palsy develops over the course of a few hours and worsens for a few days. After a couple of weeks, it begins to improve gradually, often taking three to six months to get back to normal.
The causes of Bell’s palsy are not known. It often improves on its own, and sometimes oral steroids can help speed up recovery.
What Is Bell’s Palsy?
Facial Paralysis
Facial movements can become paralyzed (weak) due to nerve or muscle damage.Besides Bell’s palsy, stroke, and nerve injury, a few other causes of facial weakness include:
Uneven Teeth
Many people naturally have mildly or moderately uneven teeth. This typically does not cause a crooked smile. Sometimes teeth are naturally very uneven or become severely uneven due to dental conditions such as tooth decay. This can cause a smile to appear crooked.
Misaligned Jaw
The jaw structure can cause a lopsided smile if the bones or movement of the jaw are formed unevenly or become damaged due to trauma or disease (such as cancer invading the bone).
Surgery
Surgery may cause damage to the nerve branches that control mouth movements. This can occur when surgery is necessary for removal of a tumor or abscess that has grown into thefacial nerve. And sometimes a surgical error can result in accidental transection (cutting) of a nerve or nerve branch.
Aging
For some people, aging can lead to an uneven smile. This can occur as a result of wrinkles, dental issues, nerve damage, or stroke.
Smoking
Smoking may lead to mouth diseases, such as severe tooth decay, gum disease, or oral cancer. This can cause a crooked smile.
Trauma
An injury to the face can cause damage to the nerves, muscles, bones, or other tissues. Swelling can be substantial as well. This can cause a lopsided smile and an uneven appearance of the face.
After the swelling goes down and healing is complete, the face and smile can partially or fully return to normal. With severe trauma, a crooked smile can remain for the long term.
Torticollis
Torticollisis a movement disorder that causes involuntary (not on purpose) spasms and twisting of the neck. The muscles can spasm for prolonged periods, sometimes resulting in a crooked smile. This condition may be present from birth and can be associated with certain birth defects.
Associated SymptomsSymptoms associated with a lopsided smile can include:Flattening of the nasolabial fold (the angled crease at the bottom of your cheeks, near your nose)Slurred speechTrouble chewing or swallowingAdroopy eyelidAn eyelid that can’t fully close
Associated Symptoms
Symptoms associated with a lopsided smile can include:Flattening of the nasolabial fold (the angled crease at the bottom of your cheeks, near your nose)Slurred speechTrouble chewing or swallowingAdroopy eyelidAn eyelid that can’t fully close
Symptoms associated with a lopsided smile can include:
A sudden lopsided smile can be a sign of a stroke,brain aneurysm(a bulge in the wall of an artery), or an infection. This may develop over the course of hours. Rarely, a new and rapidly worsening lopsided smile can be a sign of a tumor, cancermetastasis(spreading of cancer), or a seizure (uncontrolled electrical activity in the brain).
What to Do if You Think Someone Is Having a StrokeIf you think someone is having a stroke, call 911 and stay with them until emergency help arrives. If possible, describe what you witnessed when emergency healthcare providers arrive.
What to Do if You Think Someone Is Having a Stroke
If you think someone is having a stroke, call 911 and stay with them until emergency help arrives. If possible, describe what you witnessed when emergency healthcare providers arrive.
What to Do (and Not Do) If Someone Is Having a Stroke
When to See a Healthcare Provider
If your face or mouth suddenly feels numb or if movement seems uneven, you should get medical attention right away.
Symptoms associated with an uneven smile that require urgent medical attention include:
There are different techniques that can be used for treatment of an uneven smile. Immediate treatment differs from delayed treatment.
During an emergency situation, such as a stroke or severe facial trauma, the immediate treatment involves preventing serious damage and reducing the long-term effects. This may include interventions such as blood thinners for stroke treatment or surgery for treatment of facial trauma.
After a lopsided smile has stabilized, treatment can include exercises to train the muscles.This can be directed to improve the facial appearance, as well as to prevent complications, such as choking.
In some situations, injections of Botox (botulinum toxin) can work to paralyze certain muscles to prevent a crooked appearance of the mouth.
And sometimes surgical intervention may be necessary to reconstruct the facial nerves, muscles, bone, or other structures. This can help to even out the appearance of the face.This type of surgery may also be effective for reducing the risk of certain complications, like eye damage due to an eyelid that doesn’t properly close.
Summary
A crooked smile can indicate many different medical problems. Sometimes, a person’s smile is uneven due to normal variations, and it isn’t usually anything to worry about. But a crooked smile can also mean there is a serious medical issue, such as a stroke or an infection.
It’s important to get prompt medical attention for any sudden change in facial appearance. Other causes, such as Bell’s palsy or a misaligned jaw, may need medical intervention and management to prevent complications.
Frequently Asked QuestionsGenerally, Bell’s palsy starts with stiffness or weakness of the face, including the eyelids. Blinking your eyes may feel uneven, or you might have a sensation of dryness in one of your eyes. Sometimes it can be hard to chew on one side, and your smile looks very uneven.The condition usually causes profound paralysis of one side of the face, including an inability to raise your eyebrow on one side. With Bell’s palsy, the face moves unevenly, and the sides of the face look uneven while you are resting your face.Learn MoreBell’s Palsy vs. StrokeYou should get medical attention if it is new, if it happens suddenly, or if the unevenness is severe. Complications can also be concerning, even if the cause is not dangerous.Complications may include corneal damage (to the outer layer of your eye), visual problems (due to a droopy eyelid), and the risk of choking due to chewing and swallowing problems.Common signs of a stroke include sudden weakness of one side of the face and/or body, trouble speaking or understanding language, loss of balance, dizziness, or confusion. Get prompt medical attention if you or someone else experiences these symptoms.
Generally, Bell’s palsy starts with stiffness or weakness of the face, including the eyelids. Blinking your eyes may feel uneven, or you might have a sensation of dryness in one of your eyes. Sometimes it can be hard to chew on one side, and your smile looks very uneven.The condition usually causes profound paralysis of one side of the face, including an inability to raise your eyebrow on one side. With Bell’s palsy, the face moves unevenly, and the sides of the face look uneven while you are resting your face.Learn MoreBell’s Palsy vs. Stroke
Generally, Bell’s palsy starts with stiffness or weakness of the face, including the eyelids. Blinking your eyes may feel uneven, or you might have a sensation of dryness in one of your eyes. Sometimes it can be hard to chew on one side, and your smile looks very uneven.The condition usually causes profound paralysis of one side of the face, including an inability to raise your eyebrow on one side. With Bell’s palsy, the face moves unevenly, and the sides of the face look uneven while you are resting your face.
Generally, Bell’s palsy starts with stiffness or weakness of the face, including the eyelids. Blinking your eyes may feel uneven, or you might have a sensation of dryness in one of your eyes. Sometimes it can be hard to chew on one side, and your smile looks very uneven.
The condition usually causes profound paralysis of one side of the face, including an inability to raise your eyebrow on one side. With Bell’s palsy, the face moves unevenly, and the sides of the face look uneven while you are resting your face.
Learn MoreBell’s Palsy vs. Stroke
You should get medical attention if it is new, if it happens suddenly, or if the unevenness is severe. Complications can also be concerning, even if the cause is not dangerous.Complications may include corneal damage (to the outer layer of your eye), visual problems (due to a droopy eyelid), and the risk of choking due to chewing and swallowing problems.
You should get medical attention if it is new, if it happens suddenly, or if the unevenness is severe. Complications can also be concerning, even if the cause is not dangerous.
Complications may include corneal damage (to the outer layer of your eye), visual problems (due to a droopy eyelid), and the risk of choking due to chewing and swallowing problems.
Common signs of a stroke include sudden weakness of one side of the face and/or body, trouble speaking or understanding language, loss of balance, dizziness, or confusion. Get prompt medical attention if you or someone else experiences these symptoms.
6 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Centers for Disease Control and Prevention.Stroke signs and symptoms.Grohol B, Reno D, Jennings T, Fortin G, Rolfs M.Back to play considerations in a patient with Bell’s palsy: A case report and review.Cureus. 2023 Mar;15(3):e35739. doi:10.7759/cureus.35739Johns Hopkins Medicine.Bell’s palsy.De Stefani E, Barbot A, Bertolini C, et al.A new neurorehabilitative postsurgery intervention for facial palsy based on smile observation and hand-mouth motor synergies.Neural Plast.2021;2021:8890541. doi:10.1155/2021/8890541Yoshimoto S, Sato N, Kuroki T, Rikihisa N, Ichinose M.Static reconstruction of malar region in facial paralysis: a new alternative technique for plasty of symmetric mouth appearance.J Plast Surg Hand Surg.2013;47(5):390-3. doi:10.3109/2000656X.2013.771584Kuo AA, Tritasavit S, Graham JM Jr.Congenital muscular torticollis and positional plagiocephaly.Pediatr Rev.2014;35(2):79-87; quiz 87. doi:10.1542/pir.35-2-79
6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Centers for Disease Control and Prevention.Stroke signs and symptoms.Grohol B, Reno D, Jennings T, Fortin G, Rolfs M.Back to play considerations in a patient with Bell’s palsy: A case report and review.Cureus. 2023 Mar;15(3):e35739. doi:10.7759/cureus.35739Johns Hopkins Medicine.Bell’s palsy.De Stefani E, Barbot A, Bertolini C, et al.A new neurorehabilitative postsurgery intervention for facial palsy based on smile observation and hand-mouth motor synergies.Neural Plast.2021;2021:8890541. doi:10.1155/2021/8890541Yoshimoto S, Sato N, Kuroki T, Rikihisa N, Ichinose M.Static reconstruction of malar region in facial paralysis: a new alternative technique for plasty of symmetric mouth appearance.J Plast Surg Hand Surg.2013;47(5):390-3. doi:10.3109/2000656X.2013.771584Kuo AA, Tritasavit S, Graham JM Jr.Congenital muscular torticollis and positional plagiocephaly.Pediatr Rev.2014;35(2):79-87; quiz 87. doi:10.1542/pir.35-2-79
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Centers for Disease Control and Prevention.Stroke signs and symptoms.Grohol B, Reno D, Jennings T, Fortin G, Rolfs M.Back to play considerations in a patient with Bell’s palsy: A case report and review.Cureus. 2023 Mar;15(3):e35739. doi:10.7759/cureus.35739Johns Hopkins Medicine.Bell’s palsy.De Stefani E, Barbot A, Bertolini C, et al.A new neurorehabilitative postsurgery intervention for facial palsy based on smile observation and hand-mouth motor synergies.Neural Plast.2021;2021:8890541. doi:10.1155/2021/8890541Yoshimoto S, Sato N, Kuroki T, Rikihisa N, Ichinose M.Static reconstruction of malar region in facial paralysis: a new alternative technique for plasty of symmetric mouth appearance.J Plast Surg Hand Surg.2013;47(5):390-3. doi:10.3109/2000656X.2013.771584Kuo AA, Tritasavit S, Graham JM Jr.Congenital muscular torticollis and positional plagiocephaly.Pediatr Rev.2014;35(2):79-87; quiz 87. doi:10.1542/pir.35-2-79
Centers for Disease Control and Prevention.Stroke signs and symptoms.
Grohol B, Reno D, Jennings T, Fortin G, Rolfs M.Back to play considerations in a patient with Bell’s palsy: A case report and review.Cureus. 2023 Mar;15(3):e35739. doi:10.7759/cureus.35739
Johns Hopkins Medicine.Bell’s palsy.
De Stefani E, Barbot A, Bertolini C, et al.A new neurorehabilitative postsurgery intervention for facial palsy based on smile observation and hand-mouth motor synergies.Neural Plast.2021;2021:8890541. doi:10.1155/2021/8890541
Yoshimoto S, Sato N, Kuroki T, Rikihisa N, Ichinose M.Static reconstruction of malar region in facial paralysis: a new alternative technique for plasty of symmetric mouth appearance.J Plast Surg Hand Surg.2013;47(5):390-3. doi:10.3109/2000656X.2013.771584
Kuo AA, Tritasavit S, Graham JM Jr.Congenital muscular torticollis and positional plagiocephaly.Pediatr Rev.2014;35(2):79-87; quiz 87. doi:10.1542/pir.35-2-79
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