Agenesis of the venous duct is a rare congenital anomaly resulting in abnormal drainage of the umbilical vein into the foetal venous circulation. The clinical presentation and prognosis is variable, and may depend on the specific drainage pathways of the umbilical vein. We present two foetuses with agenesis of the venous duct, both associated with a postnatal portosystemic shunt, but with markedly different postnatal clinical courses. We also review all previously reported cases to better characterise this foetal disorder and the prognosis.

Our study among an orthodontic population of 1,095 patients indicates that 9% of the subjects have at least one agenesis (3% for maxillary lateral or mandibular central/lateral incisors).

Regarding possible treatments, we evaluated the different solutions from the less invasive to the most invasive: simple space closure, space closure with laminated veneers, space opening with a cantilevered bonded bridge, space opening with implant.

Recent advances in biomimetic dentistry suggest that now is the time for a paradigm shift.

This article presents solutions to problems posed by missing teeth in the anterior sector of the arch by synthesizing three groups of parameters, those related to patients, those related to dentists, and those related to the orthodontist.

But the patient, or the parents of patients who are young children, in consultation with the treatment professionals, must make the final decision.

The use of implants to replace congenitally missing teeth is a-predictable esthetic Solution that is, paradoxically less invasive than the traditional reliance on bridges to supply the missing elements because it demands little or no sacrifice of dental tissue. But this noble goal cannot be achieved unless we can assure prospective patients that the results will be stable and esthetically satisfying over the long term. This is an issue of primordial importance in view of the tender age of the patients that are the usual candidates for this treatment modality for agenesis. And no such assurance can be proffered unless we deal with the problem in a multi-disciplinary fashion from the very outset of treatment planning. We must evaluate the space needed for a replacement not just from the standpoint of the prosthetic requirements alone but also with an assessment of the associated osseous and gingival tissues in the framework of a tri-dimensional implantplacement.