BACKGROUND: Prior studies have defined minimum mesiodistal space (MS) and faciolingual alveolar width (FAW) requirements for dental implant sites, and failure to observe these constraints may adversely impact peri-implant health and esthetics. However, to the authors' knowledge, no previous reports have established frequencies at which anterior tooth positions present favorable MS and FAW for implant accommodation. METHODS: A single examiner analyzed 205 cone-beam computed tomographic images, recording MS and FAW available for implant placement at anterior tooth positions. The examiner compared measurements with standardized implant diameters to assess anticipated implant-to-tooth distances and peri-implant bone thicknesses. RESULTS: In the esthetic zone, lateral incisor sites most frequently failed to present favorable MS. At maxillary lateral incisor positions, 22% (left) and 27% (right) of sites offered less than 2 millimeters between the proposed implant platform and the adjacent teeth. In mandibular incisor positions, implant-to-tooth distance was less than 2 mm at 79% through 97% of sites and less than 1.5 mm at 35% through 76% of sites. Over one-half of maxillary incisor sites and 78% through 95% of mandibular incisor sites exhibited FAW of less than 4 mm beyond implant diameter. CONCLUSIONS: In the population evaluated, mandibular incisor positions frequently presented unfavorable MS to accommodate conventional narrow-diameter implants. In addition, considerable proportions of mandibular incisor and maxillary lateral incisor sites may be at risk of developing unfavorable peri-implant bone thickness when conventional narrow-diameter implants are used. PRACTICAL IMPLICATIONS: Practitioners should consider small-diameter implants and nonimplant tooth replacement methods for many patients missing single mandibular incisors or maxillary lateral incisors.
BACKGROUND: Prior studies have defined minimum mesiodistal space (MS) and faciolingual alveolar width (FAW) requirements for dental implant sites, and failure to observe these constraints may adversely impact peri-implant health and esthetics. However, to the authors' knowledge, no previous reports have established frequencies at which anterior tooth positions present favorable MS and FAW for implant accommodation. METHODS: A single examiner analyzed 205 cone-beam computed tomographic images, recording MS and FAW available for implant placement at anterior tooth positions. The examiner compared measurements with standardized implant diameters to assess anticipated implant-to-tooth distances and peri-implant bone thicknesses. RESULTS: In the esthetic zone, lateral incisor sites most frequently failed to present favorable MS. At maxillary lateral incisor positions, 22% (left) and 27% (right) of sites offered less than 2 millimeters between the proposed implant platform and the adjacent teeth. In mandibular incisor positions, implant-to-tooth distance was less than 2 mm at 79% through 97% of sites and less than 1.5 mm at 35% through 76% of sites. Over one-half of maxillary incisor sites and 78% through 95% of mandibular incisor sites exhibited FAW of less than 4 mm beyond implant diameter. CONCLUSIONS: In the population evaluated, mandibular incisor positions frequently presented unfavorable MS to accommodate conventional narrow-diameter implants. In addition, considerable proportions of mandibular incisor and maxillary lateral incisor sites may be at risk of developing unfavorable peri-implant bone thickness when conventional narrow-diameter implants are used. PRACTICAL IMPLICATIONS: Practitioners should consider small-diameter implants and nonimplant tooth replacement methods for many patients missing single mandibular incisors or maxillary lateral incisors.