- Email: [email protected]
Skin graft fixation
References
Roger Davies Consultant in Special Needs Dentistry Steen Sindet-Pedersen Professor of Oral & Maxillofacial Implantology Eastman Dental Institute for Oral Health Care Sciences London UK
1. Kissun D, Rogers A, Basti M, Frame JW. General medical practitioners’knowledge of the specialty of oral and maxillofacial Surgery. Br J Oral Maxillofacial Surg 1998; 36: 15-76. 2. General Medical Council. Tomorrow’s Doctors. Recommendations on Undergraduate Medical Education. London: General Medical Council, 1993. 3. Bowden J, Scully C. Dentistry and total oral health. Br Med J 1989; 298: 186.
References 1. Devani P, Laveny K M, Howell C J T. Dental extractions in patients on Warfarin: is alteration of anticoagulant regime necessary? Br J Oral Maxillofac Surg 1998; 36: 107-l 11. 2. Drug and Therapeutics Bulletin 1993; 31: 10. 3. Palareti G, Leali N, Coccheri S et al. Bleeding complications of oral anticoagulant treatment: an inception cohort, prospective collaborative study (ISCOAT). Lancet 1996; 348: 423428. 4. Cannegieter S C, Rosendaal F R, Wintzen A R, van der Meer F J M, Vandenbroucke J P, Briet E. Optimal oral anticoagulant therapy in patients with mechanical heart valves. N Engl J Med 1995; 333: 1 l-17. 5. Sindet-Pedersen S, Ramstrom G, Bemvil S, Blomback M. Haemostatic effect of tranexamic acid mouthwash in anticoagulant treated patients undergoing oral surgery. N Engl J Med 1989; 320: 840-843. 6. Souto J, Oliver A, Zauzu-Jausoro I, Vives A, Fontcuherta J. Oral surgery in anticoagulated patients without reducing the dose of oral anticoagulant. J Oral Maxillofac Surg 1996; 54: 27-32.
RE: Devani et al. Dental extractions in patients on warfarin: is alteration of anticoagulant regime necessary? Sir, We would like to commend the authors of the recent paper ‘Dental extractions in patients on warfarin: is alteration of anticoagulant regime necessary? (Br J Oral Maxillofac Surg 1998; 36: 107-111) for highlighting what is now generally agreed to be an acceptable protocol for the dental treatment of anticoagulated patients.’ We would, however, like to make some, hopefully constructive, comments: 1. It is stated that the anticoagulant effects of warfarin following the commencement of treatment are delayed for 2-3 days. This is undoubtedly true and, by day 3, 50% of patients will have an internationally normalised ratio (INR) within the therapeutic range.2 However, 50% will not, and it is this 50% that may have continued problems with their surgical/medical management. 2. Patients with INRs > 4.0 were excluded from the study. However, the therapeutic range recommended for patients with prosthetic heart valves was documented as 3.045, and for other valvular problems 2.045. It would have perhaps been of great practical benefit to include patients with INRs up to 4.5, thereby including the full range of anticoagulated patients. 3. In the study group, patients did not have the INR repeated if it had been done within the last 5 days. This is an extended period of time, during which the INR can change dramatically, even to the extent of falling below the level of the control group. In a collaborative study, 68% of 51 5663 anticoagulated patients were within the therapeutic range. However, 26.1% were below and 5.9% were above. In a similar Dutch study4 of 123 254 INR measurements, 61% were within the appropriate therapeutic range. However, 3 1% were below and 8% above. If the majority of those patients who reside outside the therapeutic range are below the target, and 5 days elapse before surgery, then some of the study group patients are likely to have INRs similar to, or lower than, the control subjects. 4. Whilst mention is made in the text of antifibrinolytics, much work has been done on the use of agents such as tranexamic acid mouthwash5,6 in the prevention of post-extraction haemorrhage. This now forms the mainstay of many dental protocols for warfarinized patients undergoing oral surgery. Pedersen’s study indicated that in patients with INRs of between 2.5 and 4.8, a significant reduction in post-extraction bleeding could be achieved with tranexamic acid mouthwash.
SKIN GRAFT FIXATION Sir, We read the recent technical note by Johnson and colleagues on skin-graft fixation with interest’ and would agree that use of foam dressings is an excellent method for securing skin grafts. This technique, as the authors point out, is not new but offers distinct advantages over conventional and often cumbersome tie-over dressings.* Foam dressings are successful in most patients but inadequate graft-bed preparation, haematoma formation, serum collection, sheer stress, infection and technical error can contribute to graft loss.3 These problems may also be exacerbated when attempting to graft complex contoured wounds such as in the head and neck region. We have therefore extended the use of the foam dressings as described above by additionally applying negative pressure across grafted wounds to aid skin-graft take. Application of topical negative pressure (TNP) using foam suction dressings for the treatment of various wounds is a new concept in wound healing. Developed and popularized by Argenta in the USA and by Fleischmann in Germany,435 early clinical and experimental results in a variety of acute and chronic wounds suggests dramatic improvements in wound healing. The technique has also been applied for use as an adjunct to surgery including fixation of skin grafts with reported take rates of over 95%.6 An open-pore foam dressing is placed over the skin graft with a non-adherent dressing (e.g. Mepitel) interposed. A drainage tube is placed over the foam and a transparent drape (e.g. Opsite) is then used to seal the wound. Negative pressure (i.e. suction) is then delivered by using commercially available devices (VACTM Pump, KCI, Witney, Oxon, UK), wall suction or even surgical drainage bottles.7 The foam dressing then shrinks down according to the contour of the wound and provides a uniform force over the skin graft. Any fluid collections are removed by the suction effect, thereby promoting skin-graft take. Dressings may be left in situ for 34 days with 480
Operations of up to 13 hours have been shortened to as little as two-and-a-half hours, with reduced hospitalization times of about two-thirds, and often no requirements for critical care. Very simple, and possibly safer, single-staged operations are possible to functionally reconstruct the face including the dentition, and the patient may be returned to the ward wearing a new dental prosthesis. Implants have been in place for over two years. Cost savings for the purchasers in the UK have been estimated at &I7 00&&19 000 ($32 500-$35 000 US) per case. This series included 7 patients treated with customized implants. This technology has applications in many surgical specialties, and is expected to reduce perioperative morbidity and mortality figures. In the last four years, the mortality rate in Doncaster for advanced mouth cancer in 17 treated cases is two patients (11.7%) in a disease whose expected mortality for advanced stages is in the region of 70%90% at two years post surgery. One case referred from the USA involved cost savings of $150 000 for US purchasers. The apparent reduction in mortality is statistically significant (P > O.OOl).i The apparent reduction in death rate has a I:1000 chance of occurring by chance alone, and such an improvement in the two-year survival is unexpected. The sample size required to show significant reduction in mortality by half, with a 95% confidence limit, is 38 patients. Whilst a reduction in perioperative mortality (i.e. death related to treatment by surgery) might be expected in the region of IO%, as a function of the reduction of surgical trauma related to the method of reconstruction with this new technology, the apparent reduction in mortality is so unexpectedly large, it requires further investigation and explanation within a more homogeneous group of patients within clinical trials, and this is our next objective. These early findings require more detailed investigation as a matter of some urgency. For further details please access www.maxfac.com on the Internet. We are pleased to enter into any discussions with interested parties globally, with respect to developing protocols and planning multicentred clinical trials. This work is being considered for publication in the British Journal of Oral and Maxillofacial Surgery.
continuous pressures of 5&75 mmHg being applied, although the patient can be disconnected if they wish to ambulate. Argenta4 and others6 have found use of foam suction dressings enables more rapid and secure graft take compared to conventional bolster techniques. They conform readily to contoured surfaces, provide active immobilization of the graft and remove wound exudate and blood, hence minimizing haematoma or seroma formation. This technique has been used in over 40 patients with good results and no complications. We have found it is potentially a reliable method of maximizing skin-graft take but requires a good seal for optimum effect. Routine use of foam suction dressings over skin grafts should be encouraged. Paul E. Banwell FRCS Duke of Kent Research Fellow, Burns and Reconstructive Surgery Research Trust, Stoke Mandeville Hospital Aylesbury Bucks HP21 8AL UK References 1. Johnson PA, Fleming K, Avery CME. Latex foam and staple fixation of skin grafts. Br J Maxillofacial Surg 1998; 36: 141-142. 2. Rudolph R, Ballantyne DL. Skin grafts. In: McCarthy J (ed) Plastic Surgery, Vol 1, General Principles. Philadelphia: WB Saunders, 1990: 221-274. 3. The BT. Why do skin grafts fail? Plast Reconstr Surg 1979; 63(3): 323-332. 4. Argenta LC, Morykwas MJ. Vacuum-assisted closure: a new method for wound control and treatment - clinical experience. Ann Plast Surg 1997; 38: 5633517. 5. Fleischmann W, Becker U, Bischoff M, Hoekstra H. Vacuum sealing: indication, technique and results. Eur J Orthop Surg Trauma 1995; 5: 3740. 6. Blackburn JH, Boemi L, Jeffords K et al. Negative pressure dressings as a bolster for skin grafts. Ann Plast Surg 1998; 40(5): 453457. I. Banwell PE, Withey S, Holten IW. Negative pressure to promote healing. Br J Plast Surg 1998; 51(l): 79.
STEREOLITHOGRAPHY AND THE MANUFACTURE OF CUSTOMIZED IMPLANTS IN FACIAL RECONSTRUCTION: A FLAPLESS SURGICAL TECHNIQUE
Niuian S. Peckitt FRCS FFD RCS FDS RCS, Consultant Oral & Maxillofacial Surgeon Doncaster Royal Infirmary Director ComputerGen Implants Limited Doncaster UK
Sir, The Department of Oral & Maxillofacial Surgery in Doncaster has recently developed a new method of reconstruction utilizing giant customized titanium implants without the need for flap cover (World Wide Patents Pending: Mr Ninian S. Peckitt) This technology is relevant in the treatment of trauma, congenital/acquired facial deformity and cancer surgery, with applications across a range of surgical specialties, and is expected to change the way surgical implants are manufactured in general.
Reference 1. Du V Florey C. Sample size for beginners. Br Med J 1993; 306: 1181~1184.
481
Roger Davies Consultant in Special Needs Dentistry Steen Sindet-Pedersen Professor of Oral & Maxillofacial Implantology Eastman Dental Institute for Oral Health Care Sciences London UK
1. Kissun D, Rogers A, Basti M, Frame JW. General medical practitioners’knowledge of the specialty of oral and maxillofacial Surgery. Br J Oral Maxillofacial Surg 1998; 36: 15-76. 2. General Medical Council. Tomorrow’s Doctors. Recommendations on Undergraduate Medical Education. London: General Medical Council, 1993. 3. Bowden J, Scully C. Dentistry and total oral health. Br Med J 1989; 298: 186.
References 1. Devani P, Laveny K M, Howell C J T. Dental extractions in patients on Warfarin: is alteration of anticoagulant regime necessary? Br J Oral Maxillofac Surg 1998; 36: 107-l 11. 2. Drug and Therapeutics Bulletin 1993; 31: 10. 3. Palareti G, Leali N, Coccheri S et al. Bleeding complications of oral anticoagulant treatment: an inception cohort, prospective collaborative study (ISCOAT). Lancet 1996; 348: 423428. 4. Cannegieter S C, Rosendaal F R, Wintzen A R, van der Meer F J M, Vandenbroucke J P, Briet E. Optimal oral anticoagulant therapy in patients with mechanical heart valves. N Engl J Med 1995; 333: 1 l-17. 5. Sindet-Pedersen S, Ramstrom G, Bemvil S, Blomback M. Haemostatic effect of tranexamic acid mouthwash in anticoagulant treated patients undergoing oral surgery. N Engl J Med 1989; 320: 840-843. 6. Souto J, Oliver A, Zauzu-Jausoro I, Vives A, Fontcuherta J. Oral surgery in anticoagulated patients without reducing the dose of oral anticoagulant. J Oral Maxillofac Surg 1996; 54: 27-32.
RE: Devani et al. Dental extractions in patients on warfarin: is alteration of anticoagulant regime necessary? Sir, We would like to commend the authors of the recent paper ‘Dental extractions in patients on warfarin: is alteration of anticoagulant regime necessary? (Br J Oral Maxillofac Surg 1998; 36: 107-111) for highlighting what is now generally agreed to be an acceptable protocol for the dental treatment of anticoagulated patients.’ We would, however, like to make some, hopefully constructive, comments: 1. It is stated that the anticoagulant effects of warfarin following the commencement of treatment are delayed for 2-3 days. This is undoubtedly true and, by day 3, 50% of patients will have an internationally normalised ratio (INR) within the therapeutic range.2 However, 50% will not, and it is this 50% that may have continued problems with their surgical/medical management. 2. Patients with INRs > 4.0 were excluded from the study. However, the therapeutic range recommended for patients with prosthetic heart valves was documented as 3.045, and for other valvular problems 2.045. It would have perhaps been of great practical benefit to include patients with INRs up to 4.5, thereby including the full range of anticoagulated patients. 3. In the study group, patients did not have the INR repeated if it had been done within the last 5 days. This is an extended period of time, during which the INR can change dramatically, even to the extent of falling below the level of the control group. In a collaborative study, 68% of 51 5663 anticoagulated patients were within the therapeutic range. However, 26.1% were below and 5.9% were above. In a similar Dutch study4 of 123 254 INR measurements, 61% were within the appropriate therapeutic range. However, 3 1% were below and 8% above. If the majority of those patients who reside outside the therapeutic range are below the target, and 5 days elapse before surgery, then some of the study group patients are likely to have INRs similar to, or lower than, the control subjects. 4. Whilst mention is made in the text of antifibrinolytics, much work has been done on the use of agents such as tranexamic acid mouthwash5,6 in the prevention of post-extraction haemorrhage. This now forms the mainstay of many dental protocols for warfarinized patients undergoing oral surgery. Pedersen’s study indicated that in patients with INRs of between 2.5 and 4.8, a significant reduction in post-extraction bleeding could be achieved with tranexamic acid mouthwash.
SKIN GRAFT FIXATION Sir, We read the recent technical note by Johnson and colleagues on skin-graft fixation with interest’ and would agree that use of foam dressings is an excellent method for securing skin grafts. This technique, as the authors point out, is not new but offers distinct advantages over conventional and often cumbersome tie-over dressings.* Foam dressings are successful in most patients but inadequate graft-bed preparation, haematoma formation, serum collection, sheer stress, infection and technical error can contribute to graft loss.3 These problems may also be exacerbated when attempting to graft complex contoured wounds such as in the head and neck region. We have therefore extended the use of the foam dressings as described above by additionally applying negative pressure across grafted wounds to aid skin-graft take. Application of topical negative pressure (TNP) using foam suction dressings for the treatment of various wounds is a new concept in wound healing. Developed and popularized by Argenta in the USA and by Fleischmann in Germany,435 early clinical and experimental results in a variety of acute and chronic wounds suggests dramatic improvements in wound healing. The technique has also been applied for use as an adjunct to surgery including fixation of skin grafts with reported take rates of over 95%.6 An open-pore foam dressing is placed over the skin graft with a non-adherent dressing (e.g. Mepitel) interposed. A drainage tube is placed over the foam and a transparent drape (e.g. Opsite) is then used to seal the wound. Negative pressure (i.e. suction) is then delivered by using commercially available devices (VACTM Pump, KCI, Witney, Oxon, UK), wall suction or even surgical drainage bottles.7 The foam dressing then shrinks down according to the contour of the wound and provides a uniform force over the skin graft. Any fluid collections are removed by the suction effect, thereby promoting skin-graft take. Dressings may be left in situ for 34 days with 480
Operations of up to 13 hours have been shortened to as little as two-and-a-half hours, with reduced hospitalization times of about two-thirds, and often no requirements for critical care. Very simple, and possibly safer, single-staged operations are possible to functionally reconstruct the face including the dentition, and the patient may be returned to the ward wearing a new dental prosthesis. Implants have been in place for over two years. Cost savings for the purchasers in the UK have been estimated at &I7 00&&19 000 ($32 500-$35 000 US) per case. This series included 7 patients treated with customized implants. This technology has applications in many surgical specialties, and is expected to reduce perioperative morbidity and mortality figures. In the last four years, the mortality rate in Doncaster for advanced mouth cancer in 17 treated cases is two patients (11.7%) in a disease whose expected mortality for advanced stages is in the region of 70%90% at two years post surgery. One case referred from the USA involved cost savings of $150 000 for US purchasers. The apparent reduction in mortality is statistically significant (P > O.OOl).i The apparent reduction in death rate has a I:1000 chance of occurring by chance alone, and such an improvement in the two-year survival is unexpected. The sample size required to show significant reduction in mortality by half, with a 95% confidence limit, is 38 patients. Whilst a reduction in perioperative mortality (i.e. death related to treatment by surgery) might be expected in the region of IO%, as a function of the reduction of surgical trauma related to the method of reconstruction with this new technology, the apparent reduction in mortality is so unexpectedly large, it requires further investigation and explanation within a more homogeneous group of patients within clinical trials, and this is our next objective. These early findings require more detailed investigation as a matter of some urgency. For further details please access www.maxfac.com on the Internet. We are pleased to enter into any discussions with interested parties globally, with respect to developing protocols and planning multicentred clinical trials. This work is being considered for publication in the British Journal of Oral and Maxillofacial Surgery.
continuous pressures of 5&75 mmHg being applied, although the patient can be disconnected if they wish to ambulate. Argenta4 and others6 have found use of foam suction dressings enables more rapid and secure graft take compared to conventional bolster techniques. They conform readily to contoured surfaces, provide active immobilization of the graft and remove wound exudate and blood, hence minimizing haematoma or seroma formation. This technique has been used in over 40 patients with good results and no complications. We have found it is potentially a reliable method of maximizing skin-graft take but requires a good seal for optimum effect. Routine use of foam suction dressings over skin grafts should be encouraged. Paul E. Banwell FRCS Duke of Kent Research Fellow, Burns and Reconstructive Surgery Research Trust, Stoke Mandeville Hospital Aylesbury Bucks HP21 8AL UK References 1. Johnson PA, Fleming K, Avery CME. Latex foam and staple fixation of skin grafts. Br J Maxillofacial Surg 1998; 36: 141-142. 2. Rudolph R, Ballantyne DL. Skin grafts. In: McCarthy J (ed) Plastic Surgery, Vol 1, General Principles. Philadelphia: WB Saunders, 1990: 221-274. 3. The BT. Why do skin grafts fail? Plast Reconstr Surg 1979; 63(3): 323-332. 4. Argenta LC, Morykwas MJ. Vacuum-assisted closure: a new method for wound control and treatment - clinical experience. Ann Plast Surg 1997; 38: 5633517. 5. Fleischmann W, Becker U, Bischoff M, Hoekstra H. Vacuum sealing: indication, technique and results. Eur J Orthop Surg Trauma 1995; 5: 3740. 6. Blackburn JH, Boemi L, Jeffords K et al. Negative pressure dressings as a bolster for skin grafts. Ann Plast Surg 1998; 40(5): 453457. I. Banwell PE, Withey S, Holten IW. Negative pressure to promote healing. Br J Plast Surg 1998; 51(l): 79.
STEREOLITHOGRAPHY AND THE MANUFACTURE OF CUSTOMIZED IMPLANTS IN FACIAL RECONSTRUCTION: A FLAPLESS SURGICAL TECHNIQUE
Niuian S. Peckitt FRCS FFD RCS FDS RCS, Consultant Oral & Maxillofacial Surgeon Doncaster Royal Infirmary Director ComputerGen Implants Limited Doncaster UK
Sir, The Department of Oral & Maxillofacial Surgery in Doncaster has recently developed a new method of reconstruction utilizing giant customized titanium implants without the need for flap cover (World Wide Patents Pending: Mr Ninian S. Peckitt) This technology is relevant in the treatment of trauma, congenital/acquired facial deformity and cancer surgery, with applications across a range of surgical specialties, and is expected to change the way surgical implants are manufactured in general.
Reference 1. Du V Florey C. Sample size for beginners. Br Med J 1993; 306: 1181~1184.
481