Tethered Labial Frenum With Midline Diastema

A 2-year-old girl was brought for evaluation of a pinkish mass between her 2 front teeth and enlargement of the space between these teeth. Her parents were concerned that the mass may be painful because the child complained of discomfort during teeth cleanings. They also were concerned that it may be affecting her speech because she had difficulty in pronouncing certain sounds and words. The girl was otherwise healthy and had achieved normal developmental milestones. There had been no bleeding from the lesion or recent rapid enlargement and no history of feeding problems, vomiting, or previous cardiac or gastric surgeries. A comprehensive review of systems was otherwise normal.

Examination of the mouth revealed a prominent maxillary frenum that was thick and fleshy. The frenum terminated between the incisors, creating a noticeable midline gap, or diastema (A). Elevation of the upper lip caused the frenum to blanch slightly (B). The child’s younger sibling had a similar hyperplastic maxillary labial frenum (C).

The maxillary frenum is a thin mucosal tissue that connects the upper lip mucosa to the gingiva between the upper central incisors. It is primarily made up of connective tissue, with a few striated muscle fibers, which arise from the muscle bundles of the lip on either side of the midline. Its function is to provide stability to the upper lip.

The superior labial frenum arises in utero from the front nasal process.¹ The alveolar process causes the tectolabial frenum to be divided into 2 parts: the palatine papilla and the superior labial frenum. The attachment of the frenum to the gingiva moves progressively upwards and thins out as the alveolar process enlarges and maxillary incisors and canines erupt. Interruption of this process can result in an abnormally attached, hyperplastic frenum.

Hyperplastic maxillary frena are associated with a diastema of the upper central incisors and traction of the attached gingiva.² It is uncertain whether the enlarged frenum causes the diastema or whether the diastema results in the abnormal frenum.³ A diagnostic test for an abnormal frenum is to pull the upper lip forward to see whether blanching of the tissue occurs interproximally from the labial to the lingual.⁴ It has been said that a truly abnormal frenum grows with age and simple enlargement of the frenum becomes less evident with age.

An abnormal or enlarged frenum can negatively affect oral hygiene as well as speech, as in this patient. Certain sounds, like “s” cannot be pronounced properly.⁵ In addition, a number of systemic conditions are associated with an abnormal frenum. Two potentially fatal conditions associated with a hyperplastic frenum are hypoplastic left heart syndrome and Ellis-Van Creveld syndrome.^6-8 In contrast, hypoplastic or absent frena may be manifestations of infantile hypertrophic pyloric stenosis^9,10 and Saldino-Noonan syndrome (a fatal chondrodystrophy associated with multiple osseous and visceral abnormalities).¹¹ Benign associations include orodigitofacial dystosis—in which hypertrophied labial, lingual, and lateral frenula produce clefts of the upper lip—and various other oral mucosal abnormalities.¹² However, hyperplastic frena are often isolated anomalies and may be familial.

Management of hyperplastic frena with diastema is somewhat controversial. When the frenum is asymptomatic and not aesthetically displeasing, no intervention is required. When the defect affects speech or bothers the patient cosmetically, management usually consists of orthodontically closing the diastema with braces. This often results in spontaneous regression of the hyperplastic frenum.¹³ The frenum that does not spontaneously resolve after closure of the diastema is often excised to prevent scar tissue from forming between the teeth. However, there are reports of spontaneous closure of the diastema after excision of the frenum.⁵ The usual timing of excision, if needed, is during puberty. This is because the diastema often closes spontaneously on eruption of the permanent canine teeth.

If the frenum is the only cosmetic consideration, laser frenectomy may be performed and has been shown to have good results with minimal recurrence.² For extremely enlarged frenum, a lateral pedical flap, free papilla graft, free gingival mucosal graft, or similar procedure is done in addition to a surgical or laser frenectomy to reform the oral mucosa.¹⁴

This patient was referred to a pediatric otolaryngologist for further evaluation and management. The specialist discussed different treatment options, risks and benefits. The patient’s mother elected release of her tethered upper labial frenum. This was done uneventfully under general anesthesia. Gradual resolution of the diastema and speech issues was observed during follow-up.