Case report and differential diagnosis of Van der Woude's
syndrome and congenital commissural pits 

M.D. Al-Shawaf, BDS,MS;
N. J. Mani, BDS,MDS
King Sand University College of Dentistry, P.O. Box 5967, Riyadh 11432, Saudi Arabia

This article presents a rare case of Van der Woude's Syndrome consisting of bilateral congenital lip pits and bifid uvula, together with two cases of unusually deep congenital commissural pits.

Congenital lip pits are rare defects1 occurring on either side of the midline of the vermilion border. These pits may extend to 3 mm or more in diameter and up to 2 mm deep. They may be circular or pre­ sent as transverse slits.2-3 Rarely, they may be located at the apex of a nipple-like elevation. The depressions often exude saliva spontaneously or upon pressure.2 When these pits are associated with cleft-lip and palate, the condition is referred to as Van der Woude's Syndrome.4 In such a case the clefts are bilateral in over 80% of patients. A few cases have been reported in which there has been but a single pit.2 Sedano et al2 reported cases of Van der Woude's Syndrome showing adhesion between maxilla and mandible, missing or hypop­ lastic (peg) lateral maxillary incisors, ankyloglossia and cleft uvula. They also reported that the condi­ tion is transmitted as an autosomal dominant con­ dition, and that the syndrome is seen in about 75,000 - 100,000 live births and affects both sexes equally.2

In contrast to lip pits, congenital commissural pits are relatively common developmental anomalies located in the vermilion border of either, or both, angles of the mouth with tracts diverging dorsolateraly into the cheeks.5 These pits may extend up to 4 mm deep with the tissue around the opening slightly raised6 Evidence of serous secre­ tion may be seen on probing or palpation of these pits. Everett and Wescott6 noted that they are hereditary in nature, possibly an autosomal domin­ ant condition. They also reported that about 0.2% of the population show this anomaly. Baker7, how­ever, demonstrated that they could be seen in 12% of white and 20% of black population.We present one case of Van der Woude's Syn­ drome and two cases of unusually deep
commissural pits.

Case 1

An 18-year-old college student, healthy, well built Saudi male patient was examined in 1985 at King Saud University College of Dentistry Oral Medicine Clinic in Riyadh for routine dental check up. Extraoral examination showed two depressions on either side of the midline of the lower lip on the vermilion border. The pits were about 2 mm in diameter. The right pit was about 3 mm, whereas the left was about 7 mm deep. The surrounding tis­ sues were swollen giving the appearance of two dome-shaped areas (Figs. 1 & 2). A mucous secre­ tion could be easily milked out from the pits. Fur­ thermore, examination showed the presence of a partial bifid uvula. The patient was unaware of any person in his family with similar lip appearance.

Case 2

A 22-year-old American Caucasian male patient was examined in 1978 at the Oral Diagnosis Clinic of Creighton University in Nebraska, USA. Exami-nation of the lips revealed the presence of bilateral pits at the commissures of the mouth. On probing, the depth of the right pit was 8 mm and the left was 6 mm (Fig. 3), Both pits were moistened with saliva. The patient reported no discomfort at anytime since he was unaware of the condition. The midline of the lower lip was slightly depressed.

Case 3

A 20-year-old white male patient, having had routine dental check up in 1979 from the Oral Diagnosis Clinic at Creighton University, was found to have bilateral congenital commissural pits (Figs. 4 & 5). The pit on the right side was about 7 mm deep, whereas that on the left was about 4 mm deep. Both pits were asymptomatic, and showed the presence of saliva on probing.

Developmental abnormaiities of the lips are vari­ ed. Some of them, as in cleft lips, may have a func­ tional and esthetic significance, whereas others, like macrocheilia and double lips, have only an esthetic significance.8 Congenital lip pits may have some questionable esthetic consideration, whereas commissural pits are generally unnoticed even by the patients. The extreme rarity of the lip pits1 and their apparently harmless nature make them clinically insignificant.

Congenital mucous secreting fistulae of the lower lip associated with cleft lip and palate are observed in Van der Woude's Syndrome,4-9 an abnormality which may have other associated developmental anomalies. In the present series, Case 1 had secreting fistulae of the lower lip and a bifid uvula. Since bifid uvula is the mildest form of a cleft palate,8 the present case could be a form of Van der Woude's Syndrome rather than an isolated congenital lip pit.4 Whether such pit occurs in iso­ lation, or in combination with other developmental anomalies, the nature of the mucous secreting fis­ tulae is disputable. These pits could be ectopic salivary glands, or part of the mechanism that keeps the vermilion border moist. In some cases, their surgical removal may be warranted due to esthetic considerations.

While relatively common, commissural pits are usually hidden and may first be noticed by an astute clinician. Whether they represent accessory salivary glands, or areas of incomplete obliteration of the ectoderm by a deficient mesenchymal prolif­ eration in the line of fusion of the embryonal man­ dibular and maxillary processes, is left to specula­ tion. Pits with salivary secretion may indicate the former possibility, whereas just blunt depressions at the commissures suggest the latter. In either case, because of the innocuous and inconspicuous nature of the pits, no treatment is generally required.

Both kinds of pits can easily be differentiated from inflammatory or neoplastic lesions of the angle of the mouth, or the midline of the lower lip in that they are bilateral, clean, non-inflamed depressions that lack ulceration.3

The term commissural lip pits, used in some references, might be confused with congenital commissural pits that are located at the commis­ sure of the lips.

The authors would like to thank Mrs. Estrella Samaniego and Miss Corazon Alano for their help with this manuscript, and Mr. Dick Ramilla for the preparation of photographs.