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Computed tomographic evaluation of bone formation after secondary bone grafting of alveolar clefts
KAJUN
1213
VARGERVIK
6. Paulin G, Astrand P, Rosenquist JB, et al: Intermediate bone grafting of alveolar clefts. J Craniomaxillofac Surg 16:2, 1988 7. Bergland 0, Semb G, Abyholm FE: Elimination of the residual alveolar cleft by secondary bone grafting and subsequent orthodontic treatment. Cleft Palate J 23:175, 1986 8. Kindelan JD, Nashed RR, Bromige MR: Radiographic assessment of secondary autogenous alveolar bone grafting in cleft lip and palate patients. Cleft Palate Craniofac J 34:195, 1997 9. Long RE Jr, Spangler BE, Yow M: Cleft width and secondary alveolar bone graft success. Cleft Palate Craniofac J 32:420, 1995 10. Lilja J, Moller M, Friede H, et al: Bone grafting at the stage of mixed dentition in cleft lip and palate patients. Scand J Plast Reconstr Surg 21:73,1987 11. Imo M, Kochi S, Matsui K, et al: Secondary bone grafting of alveolar clefts using autogenous particulate cancellous bone and marrow harvested from iliac bone. J Jpn Cleft Palate Assoc 19:22, 1994
J Oral Maxillofac 57:1213, 1999
12. van der Meij AJW, Baart JA, PrahLAndersen tomography in evaluation of early secondary Oral Maxillofac Surg 23:132, 1994
B, et al: Computed bone grafting. Int J
13. Rosenstein SW, Long RI?Jr, Dado DV, et al: Comparison of 2-D calculations from periapical and occlusal radiographs versus 3-D calculations from CAT scans in determining bone support for cleft-adjacent teeth following early alveolar bone grafts. Cleft Palate Craniofac J 34:199, 1997 14. Kaysinger KK, Nicholson NC, Ramp WK, et al: Toxic effects of wound irrigation solutions on cultured tibiae and osteoblasts. J Orthop Trauma 9:303,1995 15. Kearns GMB, Perrott DH, Sharma A, et al: Placement of endosseous implants in grafted alveolar clefts. Cleft Palate
Craniofac J 34:520, 1997 16. Hamamoto N, Hamamoto Y, Kobayasbi T: Tooth autotransplantation into the bone-grafted alveolar cleft: Report of two cases with histologic tindings. J Oral Maxillofac Surg 56: 145 1, 1998
Surg
Discussion Computed Tomographic Evaluation of Bone Formation After Secondary Bone Grafting of Alveolar Clefts Karin
Vargervik, DDS
Professor and Chair, Department of Growth and School of Dentistry, University of California-San Francisco, California; e-mail: [email protected]
Development, Francisco, San
Secondary bone grafting to the alveolar cleft bony defect has come into wide use the last few years. There are many advantages to successful bone fill of the alveolar bony defect and, at this time, the procedure can be considered part of standard care for patients with oronasal clefts. However, questions still remain, particularly with regard to timing of the procedure as it relates to growth, dental development, width of cleft and edentulous space, and stage of orthodontic treatment. The bone volume achieved by the procedure is important, particularly if a missing tooth, usually the lateral incisor, is to be replaced by an implant. It is generally the width rather than the height of the repaired alveolus that determines whether there is enough bone for successful incorporation of an implant. In most studies and in day-to-day clinical practice, either a periapical or a panoramic radiograph is used to assess the outcome of the alveolar bone grafting procedure. Bone fill across the defect and bone height can be assessed on these radiographs, but not the width. This is generally assessed by palpation or inspection at the time of implant placement. A method that allows accurate volume assessment would be helpful both in treatment planning and in follow-up studies such as the one presented here. In this study on 15 patients with alveolar clefts, alveolar defect volume was studied at the time of bone grafting and at 3 and 12 months after the procedure. The average volume
was found to be greater than the original defect as determined by the investigators’ measuring technique; the mean volume at 12 months was found to be about the same as the original defect. More important than the averages is the variability of the outcome. At 3 months, 3 of the patients showed loss of about half of the volume. From 3 to 12 months, the volume increased in 2 patients, but decreased in others. The increase in volume was assumed to be caused by erupting teeth. Unfortunately, the authors have not described the cleft surroundings with regard to the presence or absence of teeth or width of the gap between the teeth on the margin of the 2 maxillary segments. Presumably these are factors tbat explain, or at least contribute to a better understanding of, the variability in outcome. There is general agreement that alveolar bone exists only in association with teeth. There appears to be a zone adjacent to a tooth where the alveolar bone is maintained. The exact area of alveolus that a tooth supports has not been established, at least in the literature. However, it is clear that the wider the gap between the teeth, the more alveolar bone loss occurs. This principle also comes into play in the grafted alveolus. Eruption of teeth into the area, orthodontic movement of teeth into the area, or placement of an implant will all support the bone created by the grafting procedure. Thus, I agree with the authors’ conclusion, which also is in agreement with the preliminary findings in a prospective study reported by our group,’ that implants should be placed relatively early when they are to be used in patients with bone grafted alveolar clefts.
Reference 1. Kearns GMB, Perrott DH, Sharma A, et al: Placement of endosseous implants in grafted alveolar defects. Cleft Palate Craniofac J 34:520, 1997
1213
VARGERVIK
6. Paulin G, Astrand P, Rosenquist JB, et al: Intermediate bone grafting of alveolar clefts. J Craniomaxillofac Surg 16:2, 1988 7. Bergland 0, Semb G, Abyholm FE: Elimination of the residual alveolar cleft by secondary bone grafting and subsequent orthodontic treatment. Cleft Palate J 23:175, 1986 8. Kindelan JD, Nashed RR, Bromige MR: Radiographic assessment of secondary autogenous alveolar bone grafting in cleft lip and palate patients. Cleft Palate Craniofac J 34:195, 1997 9. Long RE Jr, Spangler BE, Yow M: Cleft width and secondary alveolar bone graft success. Cleft Palate Craniofac J 32:420, 1995 10. Lilja J, Moller M, Friede H, et al: Bone grafting at the stage of mixed dentition in cleft lip and palate patients. Scand J Plast Reconstr Surg 21:73,1987 11. Imo M, Kochi S, Matsui K, et al: Secondary bone grafting of alveolar clefts using autogenous particulate cancellous bone and marrow harvested from iliac bone. J Jpn Cleft Palate Assoc 19:22, 1994
J Oral Maxillofac 57:1213, 1999
12. van der Meij AJW, Baart JA, PrahLAndersen tomography in evaluation of early secondary Oral Maxillofac Surg 23:132, 1994
B, et al: Computed bone grafting. Int J
13. Rosenstein SW, Long RI?Jr, Dado DV, et al: Comparison of 2-D calculations from periapical and occlusal radiographs versus 3-D calculations from CAT scans in determining bone support for cleft-adjacent teeth following early alveolar bone grafts. Cleft Palate Craniofac J 34:199, 1997 14. Kaysinger KK, Nicholson NC, Ramp WK, et al: Toxic effects of wound irrigation solutions on cultured tibiae and osteoblasts. J Orthop Trauma 9:303,1995 15. Kearns GMB, Perrott DH, Sharma A, et al: Placement of endosseous implants in grafted alveolar clefts. Cleft Palate
Craniofac J 34:520, 1997 16. Hamamoto N, Hamamoto Y, Kobayasbi T: Tooth autotransplantation into the bone-grafted alveolar cleft: Report of two cases with histologic tindings. J Oral Maxillofac Surg 56: 145 1, 1998
Surg
Discussion Computed Tomographic Evaluation of Bone Formation After Secondary Bone Grafting of Alveolar Clefts Karin
Vargervik, DDS
Professor and Chair, Department of Growth and School of Dentistry, University of California-San Francisco, California; e-mail: [email protected]
Development, Francisco, San
Secondary bone grafting to the alveolar cleft bony defect has come into wide use the last few years. There are many advantages to successful bone fill of the alveolar bony defect and, at this time, the procedure can be considered part of standard care for patients with oronasal clefts. However, questions still remain, particularly with regard to timing of the procedure as it relates to growth, dental development, width of cleft and edentulous space, and stage of orthodontic treatment. The bone volume achieved by the procedure is important, particularly if a missing tooth, usually the lateral incisor, is to be replaced by an implant. It is generally the width rather than the height of the repaired alveolus that determines whether there is enough bone for successful incorporation of an implant. In most studies and in day-to-day clinical practice, either a periapical or a panoramic radiograph is used to assess the outcome of the alveolar bone grafting procedure. Bone fill across the defect and bone height can be assessed on these radiographs, but not the width. This is generally assessed by palpation or inspection at the time of implant placement. A method that allows accurate volume assessment would be helpful both in treatment planning and in follow-up studies such as the one presented here. In this study on 15 patients with alveolar clefts, alveolar defect volume was studied at the time of bone grafting and at 3 and 12 months after the procedure. The average volume
was found to be greater than the original defect as determined by the investigators’ measuring technique; the mean volume at 12 months was found to be about the same as the original defect. More important than the averages is the variability of the outcome. At 3 months, 3 of the patients showed loss of about half of the volume. From 3 to 12 months, the volume increased in 2 patients, but decreased in others. The increase in volume was assumed to be caused by erupting teeth. Unfortunately, the authors have not described the cleft surroundings with regard to the presence or absence of teeth or width of the gap between the teeth on the margin of the 2 maxillary segments. Presumably these are factors tbat explain, or at least contribute to a better understanding of, the variability in outcome. There is general agreement that alveolar bone exists only in association with teeth. There appears to be a zone adjacent to a tooth where the alveolar bone is maintained. The exact area of alveolus that a tooth supports has not been established, at least in the literature. However, it is clear that the wider the gap between the teeth, the more alveolar bone loss occurs. This principle also comes into play in the grafted alveolus. Eruption of teeth into the area, orthodontic movement of teeth into the area, or placement of an implant will all support the bone created by the grafting procedure. Thus, I agree with the authors’ conclusion, which also is in agreement with the preliminary findings in a prospective study reported by our group,’ that implants should be placed relatively early when they are to be used in patients with bone grafted alveolar clefts.
Reference 1. Kearns GMB, Perrott DH, Sharma A, et al: Placement of endosseous implants in grafted alveolar defects. Cleft Palate Craniofac J 34:520, 1997