The small strip of tissue connecting the inside of your upper lip to the gum above your front teeth is called the labial frenulum, or more precisely, the superior labial frenulum. Dentists and surgeons sometimes call it the maxillary labial frenum. It is one of several frenula in your mouth, but it tends to be the most noticeable because you can feel it easily with your tongue or see it by pulling your upper lip outward in front of a mirror. Despite being a tiny fold of tissue most people never think about, it has a surprisingly active role in dental health, infant feeding debates, and even forensic medicine.
What the Frenulum Is Made Of
The superior labial frenulum looks like a thin flap of skin, but structurally it is a fold of mucosa, the soft, moist lining inside your mouth. Underneath that mucosal fold sits a layer of connective tissue that anchors to the bone between your two upper front teeth.1PubMed. What is a superior labial frenulum? An anatomical and histological study It is not a muscle and it does not contain muscle fibers, so it does not actively move. Instead, it acts like a tether, limiting how far your upper lip can pull away from the gum.
The frenulum attaches at different heights on the gum depending on the person. In some people it connects high up near the lip fold and barely touches the gum tissue. In others it extends all the way down between the front teeth and even reaches the roof of the mouth behind them. These attachment differences are at the heart of almost every clinical question about the frenulum: whether it needs treatment, whether it is causing a gap, or whether it is interfering with breastfeeding.
How It Forms Before Birth
The frenulum develops from structures called tectolabial bands during fetal growth. As the face takes shape in utero, these bands divide to form both the labial frenulum and the small bump of tissue behind the upper front teeth known as the palatine papilla.2Journal of the Korean Academy of Pediatric Dentistry. Management of the Maxillary Labial Frenum Essentially, the frenulum is a leftover remnant of embryonic connective tissue that once helped shape the developing upper jaw and lip. Everyone is born with one to some degree. A study that examined newborns found that every single baby had a visible superior labial frenulum, though the size and thickness varied considerably.3PubMed Central. The Superior Labial Frenulum in Newborns: What Is Normal?
Not All Frenula Look the Same
Clinicians have developed classification systems to describe the range of frenulum shapes and attachment points. The two most widely used are Sewerin’s system, which categorizes the frenulum by its visible shape (simple, persistent, double, nodular, and so on), and Placek’s system, which focuses on where the tissue attaches along the gum.4PubMed Central. Assessment and Management of Maxillary Labial Frenum—A Scoping Review Under Placek’s system, there are four types ranging from a high attachment near the lip fold (Type I) down to one that penetrates all the way to the palate (Type IV). Types III and IV, in which the frenulum extends into or through the gum tissue between the teeth, are the ones most likely to need treatment.
The simple frenulum, a thin and unobtrusive fold, is the most common shape across all jaw types. However, the thicker, lower-attaching forms show up more frequently in people with certain skeletal jaw patterns. One cross-sectional study found that the papillary and papillary-penetrating types were significantly more common in individuals with a particular underbite-related jaw pattern and were also associated with a gap between the front teeth.5PubMed Central. Prevalence of variations in morphology and attachment of maxillary labial frenum in various skeletal patterns – A cross-sectional study Sex does not appear to play a role: research has found no significant relationship between gender and frenulum type.6Annals of Medical Research. Types of the maxillary labial frenulum and median diastema in children: A cross-sectional study
How the Frenulum Changes as You Grow
One of the most important and least appreciated facts about the frenulum is that it does not stay the same throughout life. In infants, the frenulum often appears thick and low-set, sometimes extending well past the gum ridge. This alarms many parents, but it is usually a normal part of early anatomy. As the jaw grows and the adult teeth begin to come in, the frenulum’s attachment point tends to migrate upward, away from the teeth and toward the lip fold.7JAMA Otolaryngology–Head & Neck Surgery. Anatomic Distribution of the Morphologic Variation of the Upper Lip Frenulum Among Healthy Newborns Older children are far more likely to have a mucosal or gingival frenulum than the papillary-penetrating type commonly seen in babies.
This natural recession is exactly why many dentists and orthodontists advise waiting before deciding whether a child’s frenulum needs treatment. What looks alarmingly thick at age two may be completely unremarkable by age eight.
The “Lip Tie” Debate
In recent years, the term “lip tie” has gained enormous popularity among parents, lactation consultants, and some healthcare providers. A lip tie describes a situation where the superior labial frenulum is thought to be so tight or thick that it prevents a baby from flanging their upper lip properly during breastfeeding, leading to a poor latch, pain for the mother, and inadequate milk transfer.8PubMed. Diagnosing and understanding the maxillary lip-tie (superior labial, the maxillary labial frenum) as it relates to breastfeeding
The concept is real in the sense that soft tissue abnormalities in the mouth can interfere with feeding. But the evidence supporting routine surgical release of the upper lip frenulum for breastfeeding difficulties is weak. A systematic review found no randomized controlled trials supporting the practice, and the classification system most commonly used to grade the severity of lip ties (the Kotlow classification) has not proven reliable in predicting breastfeeding problems.9PubMed. Upper Lip Tie and Breastfeeding: A Systematic Review Another study found no correlation between frenulum grade and breastfeeding comfort, pain scores, or latch quality.10PubMed. Upper Lip Tie: Anatomy, Effect on Breastfeeding, and Correlation With Ankyloglossia
This does not mean that no baby’s frenulum ever causes a feeding problem. But it does mean the diagnosis is being made far more often than the evidence warrants. Frenotomy procedures for lip ties have been increasing, and practice patterns vary widely among different types of providers.11International Journal of Pediatric Otorhinolaryngology. Pediatric frenotomy practice patterns: A survey of pediatric dentists, otolaryngologists and surgeons A parent told their baby has a lip tie should feel comfortable asking for a second opinion, particularly from a provider outside the practice recommending the procedure.
The Gap Between Your Front Teeth
A gap between the upper front teeth, called a midline diastema, is one of the most visible effects a frenulum can have. When the frenulum attaches low enough to pass between the front teeth, it can physically hold them apart or prevent the gap from closing on its own. A systematic review of the dental literature confirmed that two specific frenulum types, the papillary and papillary-penetrating varieties, are associated with this gap.12International Journal of Pediatric Otorhinolaryngology. Association between superior labial frenum and maxillary midline diastema — a systematic review
The tricky part is knowing when the gap is a problem versus a normal stage of dental development. In children, a space between the front teeth is extremely common and often closes naturally once the permanent canine teeth push through and crowd the incisors together. For that reason, the standard recommendation is to delay any frenectomy until the permanent lateral incisors have erupted, because the gap may resolve on its own.12International Journal of Pediatric Otorhinolaryngology. Association between superior labial frenum and maxillary midline diastema — a systematic review If the gap persists after those teeth are in, and the frenulum is clearly involved, then a procedure to release or remove it becomes a reasonable step, usually in coordination with orthodontic treatment.
Gum Health and the Frenulum
A frenulum that attaches close to the gum line can pull on the gum tissue whenever you move your lip, especially during eating or brushing. Over time, this repeated tugging can contribute to gum recession, where the gum pulls back from the tooth and exposes the root. One regression analysis identified a high frenulum attachment as a significant contributor to gum recession, alongside factors like age, smoking, and aggressive toothbrushing.13PubMed. Gingival recession: epidemiology and risk indicators in a university dental hospital in Turkey
A low-set frenulum can also make brushing and flossing the area between the front teeth more difficult, which may lead to plaque buildup. If your dentist notices that the frenulum is interfering with hygiene or actively pulling your gums away from the teeth, they may suggest a frenectomy for periodontal reasons rather than cosmetic ones.
Frenectomy Procedures
A frenectomy is the surgical removal or release of the frenulum. It is a minor procedure that can be done in a dental or surgical office, often under local anesthesia. The two main approaches are traditional scalpel surgery and laser surgery, and recent research has compared them head to head.
In general, laser frenectomy is faster and causes less bleeding and less immediate pain. One trial found the average surgical time for a laser procedure was under four minutes, compared to roughly twelve minutes for the scalpel approach.14PubMed Central. Comparative frenectomy with conventional scalpel and dual-waved laser in labial frenulum Patients in the laser group also reported lower pain scores in the first few days and less difficulty chewing and speaking.15PubMed Central. Maxillary labial frenectomy: a randomized, controlled comparative study of two blue (445 nm) and infrared (980 nm) diode lasers versus surgical scalpel However, the scalpel group showed slightly faster tissue healing at the one-week mark in at least one study.16PubMed Central. Evaluating diode laser and conventional scalpel techniques in maxillary labial frenectomy for patient perception, tissue healing, and clinical efficacy: six-month results of a randomized controlled study By two weeks, outcomes between the methods tend to converge.
Among laser options, research suggests a blue diode laser (445 nm) performs somewhat better than an infrared one (980 nm), with lower immediate pain and faster healing.15PubMed Central. Maxillary labial frenectomy: a randomized, controlled comparative study of two blue (445 nm) and infrared (980 nm) diode lasers versus surgical scalpel These differences are meaningful in the first week of recovery but generally even out within a month.
No matter which technique is used, complications are rare. A retrospective study of frenectomies in children reported no adverse outcomes beyond minor, expected pain and swelling.17International Orthodontics. Safety and efficacy of maxillary labial frenectomy in children: A retrospective comparative cohort study
Torn Frenulum and What It Means
The frenulum tears fairly easily. A blow to the face, a fall, or even biting into something too aggressively can rip the thin tissue. In most adults and older children, a torn frenulum is a minor injury. It bleeds a lot because the mouth has rich blood supply, but it typically heals on its own without stitches.
In infants and toddlers, though, a torn labial frenulum has a more complicated significance. For decades, a torn frenulum in a non-mobile infant (one too young to crawl or walk) was considered a potential red flag for non-accidental injury, since a baby who cannot move independently is unlikely to fall and hit their mouth. This association led to its inclusion in some child abuse screening guidelines. However, a systematic review concluded that the current literature does not support diagnosing abuse based on a torn labial frenulum in isolation.18PubMed Central. Diagnosing abuse: a systematic review of torn frenum and other intra‐oral injuries A torn frenulum should prompt further evaluation and context, but by itself it is not proof that harm was inflicted.
Frenulum Piercings
Oral piercings through the superior labial frenulum, sometimes called a “smiley” piercing because the jewelry is only visible when you smile, have become an established trend in body modification culture. The piercing passes through the thin mucosal fold and typically uses a small curved barbell or captive bead ring. Because the tissue is thin and has minimal nerve density, the piercing itself is usually described as relatively low-pain compared to other oral piercings.
That said, the frenulum is not designed to hold hardware. The tissue is delicate and the mouth is a challenging environment for wound healing, with constant saliva exposure, food particles, and bacterial load. Common complications include the jewelry migrating through the tissue over time (eventually falling out), gum erosion where the ring rests against the gum line, and enamel wear on the front teeth from metal contact. People with a very thin or short frenulum may not have enough tissue to support a piercing at all. If you are considering one, choosing a skilled piercer who can evaluate your anatomy beforehand reduces the risk of problems, but rejection of the jewelry remains common with this placement regardless of technique.
Other Frenula in the Mouth
The superior labial frenulum gets the most attention, but it is not the only frenulum you have. There is a corresponding frenulum under your lower lip (the inferior labial frenulum), which connects the inner lower lip to the gum below the front bottom teeth. It is usually thinner and less prominent, and it causes far fewer clinical issues.
The lingual frenulum, the one under your tongue, is probably the second most discussed. When the lingual frenulum is unusually short or tight, it restricts tongue movement and is commonly known as tongue-tie, or ankyloglossia. This condition affects speech, feeding, and oral function more directly than the upper lip frenulum does, and it has a much stronger evidence base for surgical release when it causes functional problems.
Your cheeks also have frenula, sometimes called buccal frenula, which connect the inner cheek to the gum near the premolar teeth. These are smaller and rarely cause problems, but they have recently entered the clinical conversation as “buccal ties.” Among healthcare professionals surveyed about buccal restrictions, about 87% reported that they assess for them, and an estimated 5-10% of infants were thought to be affected.19PubMed Central. The buccal frenum: Trends in diagnosis and indications for treatment of buccal-ties among 466 healthcare professionals Whether buccal ties represent a real clinical entity or another example of overdiagnosis is still being debated, and the evidence base is thin.
All of these frenula share the same basic anatomy: folds of mucosa over connective tissue that tether a movable part of the mouth to a fixed structure. They all vary in size and attachment from person to person. And the same tension exists around all of them between the impulse to treat any variation that looks unusual and the recognition that most variations fall within normal range and resolve on their own or never cause symptoms.