Dr. Alan MeltzerFROM THE DESK OF ALAN M. MELTZER DMD MScD
In this issue I will explore the formation of papilla between adjacent implants. As you may recall from my previous monograph, when a single tooth implant is placed the formation of the papilla is controlled by the distance from the crest of bone on the adjacent natural teeth to the crown contact points. The general rule is as long as the distance from the tooth contact point to the crest of bone on the adjacent teeth is 5 millimeters or less there is an excellent chance the papilla will form. Simply stated, the fate of the papilla is controlled by the attachment level of the tissue to the natural tooth and not by the situation associated with the implant side of the interproximal space.
In the case of adjacent implants, there is no tooth-associated supracrestal fiber system to support the inter-implant papilla. Additionally, in this case the position of the contact point is completely within the control of the restorative dentist and laboratory since these adjacent implants are restored by crowns. Therefore, the measure used is simply the thickness of tissue covering the interproximal bone. The average tissue thickness is 3.5 millimeters. It is for this reason that adjacent implants frequently produce black triangles rather than full papilla.
Bulb 1This aesthetic dilemma remains one of the great challenges of implant dentistry. When one replaces two central incisors, symmetry can be maintained as long as the inter-implant distance is greater than 3 millimeters (see my next monograph for further explanation). The true problem surfaces when one needs to replace either a central incisor and its adjacent lateral incisor or a canine and adjacent lateral incisor. When the implant side is compared with the opposite tooth side, there will be an obvious difference in soft tissue morphology creating an aesthetic compromise. One can expect only 3.5 millimeters of soft tissue over the bone between implants, while 5-6 millimeters or more can be expected between natural teeth. This requires the restorative dentist to alter tooth form or create a black triangle.
TeethNote the lack of symmetry of the central lateral papilla (#7 and #8 are adjacent implant crowns compared to natural teeth #9 and #10)
What is the best solution? Place one implant and cantilever off the lateral incisor. This solution works because the edentulous lateral incisor site can be augmented at the time of implant replacement. Connective tissue augmentation of the pontic site can produce almost 7 millimeters of soft tissue thickness compared to 3.4 millimeters between implants. The use of a properly placed wide-diameter implant in either the canine or central incisor site is suggested. A lateral incisor can be cantilevered off either the canine or central incisor as required. An implant with an internal connection is suggested to insure abutment stability.