Implant selection and positioning can be confidently addressed with thorough, prosthetically driven treatment planning. The appropriate size and spacing of dental implants in the posterior is determined by carefully assessing the anatomy of the ridge, the restorative space available, and the long-term needs of the patient.
The edentulous span must be evaluated to identify the appropriate implant size for each site. First, the mesial-distal distance between the teeth adjacent to the edentulous space is measured. Then, the implant sizes are determined, allowing for 1.5 mm of space between the shoulder of each implant and the neighboring tooth, and 3 mm between adjacent implants. Buccolingually, allow for 1–2 mm of bone on each side of the implant.
The following case shows how to navigate the implant spacing and selection considerations for restoration of an edentulous span in the posterior. By properly evaluating the residual ridge and surrounding anatomy, and positioning the implants to support the ideal prosthetic outcome, dental function is restored for the patient predictably and efficiently despite the presence of a large buccal defect at the time of implant placement.
By properly evaluating the residual ridge and surrounding anatomy, and positioning the implants to support the ideal prosthetic outcome, dental function is restored for the patient predictably and efficiently.
With an edentulous span measuring approximately 26 mm long, the diameter of the three implants was calculated as follows:
Implant spacing and selection in the posterior can be determined with confidence by carefully evaluating the patient’s anatomy, performing simple calculations, accounting for any bone deficiencies, and visualizing the prosthetic outcome from the outset. Virtually any obstacle can be overcome with proper treatment planning, especially by taking advantage of the digital tools, implant design innovations, bone grafting materials and prosthetic options available to the modern practitioner.