Implant Placement in Developing Patients
Thomas J. Salinas, DDS
Implant placement in the partially edentulous mandible is achieving a high level of success and has predictable application in individuals who are missing single and multiple teeth.1 Dental implants can be used to replace missing teeth due to restorative failure, periodontal disease, or congenital absence. Most guidelines for placement of dental implants are well-defined. On the other hand, guidelines for timing of dental implant placement in the developing patient are ill-defined, and published literature on the topic is spattered with case reports and anecdotal extrapolations.
Orthodontic literature on facial growth in adolescents gives some general guidelines in treating the craniofacial skeleton from anticipated averages in space allocation. Three-dimensional growth of the craniofacial skeleton should be considered in the order of width, length, and height, of dental arches. Growth in width of dental arches is complete by the age of 12 in most adolescents, while growth in width of both jaws tends to be complete before the adolescent growth spurt and is affected minimally by further adolescent growth changes. The balance of growth throughout early adolescence and adulthood is of length and height. Therefore, evaluations of this growth, in most cases, can be assessed by lateral cephalometric radiographs.
Growth in length of both jaws continues through puberty. In the average female, it ceases by 2 to 3 years after the first menstrual period. In males, growth in length does not decline to the basal adult level until about 4 years after attainment of sexual maturity.
Vertical height growth of the jaw and face continues longer in both sexes than growth in length. Increases in facial height and concomitant eruption of teeth continue throughout life, but the decline to the adult level often does not occur until ages 17 or 18 in females, and in the early 20s in males.2 Changes in facial height are apparent when implants are placed before completion of the majority of facial height growth.
Frequently, orthodontics may be used as an adjunct in these cases to achieve space augmentation laterally and vertically. However, post-treatment infraocclusion may be apparent with implant restorations. This seems to be more apparent in patients with limited incisor contact or where incisor stability is questionable.3 Therefore, orthodontic treatment should be directed not only toward space achievement, but also towards a stable incisal relationship. Due to the variability among individuals, recommendations of implant placement based strictly on chronological age are not advocated; an approach that considers skeletal maturity and growth curves is more prudent. Wrist radiographs can give an assessment of epiphyseal plate closure that indicates skeletal maturity. Also, height and weight charts will give some indication of the plateau desired for a stable growth phase.
Implant placement has been used extensively in adolescents afflicted with anhidrotic ectodermal dysplasia. Effects on the facial and craniofacial development are not considered detrimental when comparing those treated with dental implants to those not treated.4 Bonded FPDs have been utilized with a somewhat predictable outcome. On average, single-tooth replacement with relatively nonmobile abutment teeth is preferred, and an average of 7 years without debonding can be expected. Definitive long-term treatment with bonded FPDs, however, is questionable.
Implant placement in the developing patient should be carefully scrutinized, and age-related growth changes may direct treatment to a more provisional alternative.
*Assistant Professor, Department of Otolaryngology, University of Nebraska medical Center, Omaha, Nebraska.
- Hultin M, Gustafsson A, Klinge B. Long-term evaluation of osseointegrated dental implants in the treatment of partly edentulous patients. J Clin Periodontol 2000;27(2):128-133.
- Proffit W. Contemporary Orthodontics. St. Louis, MO: Mosby; 1986.
- Thilander B, Odman J, Jemt T. Single implants in the upper incisor region and their relationship to the adjacent teeth. An 8-year follow-up study. Clin Oral Impl Res 1999;10(5):346-355.
- Johnson EL, Roberts MW, Guckes AD, et al. Analysis of craniofacial development in children with hypohidrotic ectodermal dysplasia. Am J Med Genet 2002;112(4):327-334.