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Comparison of electrosurgery with conventional fiberotomies on rotational relapse and gingival tissue in the dog
Comparison of electrosurgery with conventional fiberotomies on rotational relapse and gingival tissue in the dog Laurie Lee Fricke, BS, DDS,* and Christopher A. N. Rankine, DDS, MMedSc** New Orleans, La.
The relapse tendency of orthodontically rotated teeth after electrosurgical circumferential fiberotomies and after conventional scalpel blade surgical procedures was demonstrated with a split-mouth procedure involving the maxillary second incisors of five mongrel dogs. The second incisors were rotated orthodontically an average of 63.5 ° over a 4-month period. Electrosurgical circumferential fiberotomies were performed on the designated second incisors, and circumferential fiberotomies with a scalpel blade were performed on the contralateral incisors. The teeth were retained for 1 month and relapse was measured 2 months postretention. Wound healing was demonstrated by measurement of sulcus depths and facial gingival recession preoperatively and at 1, 2, 3, 4, and 9 weeks after surgery. In both groups, the sufcus depths had decreased about 2 mm and the facial gingiva had receded 0.3 mrn 9 weeks after surgery. Two months postretention there was an average 25% relapse in the teeth treated by means of a circumferential fiberotomy with a scalpel blade compared to an average 23% relapse in those treated by means of a circumferential fiberotomy with electrosurgery. No significant difference was seen between the two techniques. (AM J ORTHOD DENTOFACORTHOP 1990;97:405-12.)
M a i n t e n a n c e of the correction of severely rotated teeth is a concern in orthodontic therapy. A significant cause of relapse is thought to be the gingival and transseptal fibers, which are stretched and twisted as the tooth is rotated. 1-4To reduce the potential relapse, a circumferential supracrestal fiberotomy is performed. Conventionally, a scalpel blade is inserted into the depth of the gingival sulcus to sever the twisted gingival fibers from the rotated tooth? The purpose of this study was to compare the results of fiberotomies performed by means of electrosurgery and fiberotomies performed by the conventional scalpel blade procedure. The specific aims were to compare (I) amount of relapse, (2) amount of gingival recession, and (3) sulcus depth. The literature offers substantial indication that circumferential fiberotomies significantly reduce relapse following orthodontic rotation? "9 For example, Pinson and Strahan 7demonstrated, in human patients, that after 23 weeks of retention a mean relapse of 56.5% of the original rotation occurred where no fiberotomies had been performed. The teeth on which fiberotomies were
From Louisiana State University School of Dentistry. *Postgraduate student, Department of Orthodontics, **Assistant Professor, Department of Orthodontics. 8/1112599
performed displayed a reduced relapse of 20% of the original rotation after 16 to 28 weeks of retention. In dogs, fiberotomies significantly reduce the amount of relapse. Wiser 8 reported a mean 11.2% relapse after fiberotomy compared with a mean 43.8% relapse when no fiberotomy was performed. Brain '° reported a mean 1.1% relapse after fiberotomy compared with a mean 43.3% in the control. The literature supports the belief that fiberotomies significantly reduce relapse following orthodontic rotation. However, in a questionnaire sent to 1000 orthodontists in the United States, 75% of the respondents stated that they did not use fiberotomies? The lack of clinical acceptance despite the demonstrated advantage suggests to us the need to consider an alternate technique that may be more clinically acceptable. MATERIAL AND METHODS A split-mouth procedure involving the maxillary second incisors of five mongrel dogs was used. The maxillary second incisors were selected as the experimental teeth because comparable methods were used in previous studies on dogs and because the dimensions of the tooth and alveolar structure are similar to those of human beings. The procedure involved rotation of the maxillary incisors followed by a circumferential fiberotomy with a scalpel blade on one side of the arch 405
406
Fricke and Rankine
Am. J. Orthod. Dent~?~lc, Orthop.
May 1990
Fig. 1. Labiolingual appliance with elastic chain to rotate second incisors.
C Fig. 2. Electrode passed around tooth with four separate applications.
and an eleetrosurgical circumferential fiberotomy on the contralateral side. Each dog was sedated, and a shallow groove was made on the facial enamel at the crest of the marginal gingiva as a reference for measurement of the amount of gingival recession. Another groove was made on the incisal edge to help measure the amount of rotation and relapse. To prevent occlusal interference with the appliance, the mandibular incisors were extracted and the mandibular canines were reduced to the gingival crest after pulP0tomies were performed. Two impressions were made, and from the stone casts a specially designed labiolingual appliance was fabricated and prerotational measurements were made. The appliance consisted of band material adapted to the canines and the third incisors. Perforations were
made on each band to allow for mechanical retention. One 0.036 inch round wire from canine to canine was soldered to the labial surface of the bands and another to the lingual surface. Small cleats were welded to the wires. One week later the appliances were bonded to the third incisors and the maxillary canines. Orthodontic buttons were bonded to the labial and lingual surfaces of the maxillary second incisors. Elastic chains were engaged from each button to a cleat on the labiolingual appliance to create a faciodistal-linguomesial rotational force (Fig. 1). The dogs were kept on a soft diet for the duration of the experiment and were seen once a week for 3 months so that hygiene could be maintained, the elastics could be changed, and the stability of the appliances could be checked. After 16 weeks of orthodontic rotation, scalpel circumferential fiberotomies were performed on one second incisor and electrosurgical circumferential fiberotomies were performed on the contralateral incisor. Surgery was performed before retention, as described in studies by Edwards, 9 Brain, ~° and Boese. ~t Immediately before the fiberotomies were performed, the sulcus depth was measured on the mesial, distal, facial, and lingual surfaces of each tooth. The technique for the scalpel fiberotomies was that described by Edwards. 6 A Bard-Parker blade was inserted to a depth approximately 3 mm below the crest of alveolar bone, severing the fibers surrounding the tooth. The technique for the electrosurgical fiberotomies was similar to the method for tissue dilation reported by Kelly and Harrison.t2 As described in their study,
Comparison of electrosurgery with conventional fiberotomies 407
Volume 97 Number 5
Fig. 3. Labiolingual appliance during retention. Ligature wire was tied from the buttons on the second incisors to the cleats on the lingual wire.
Table I. Relapse Degrees of rotation Dog 1 2 3 4 5 Mean
Scalpel 65.5 63.8 80,5 56,8 49.2 63.16
Electrosurgery 63,0 88.5 65.4 36,0 66,3 63.84
Degrees of relapse Scalpel 13,5 9.6 17.6 16.5 19.7 15.38
an Ellman Dento Surg unit (Ellman Dental Mfg. Co., Hewlett, N.Y.) was used and a fully rectified surgical current was selected, since this current provides coagulation as well as incision. A passive plate was placed under the dog's shoulders. A straight-wire electrode was held parallel and next to the tooth in the gingival sulcus and passed around the tooth approximately 1 to 2 mm below the epithelial attachment with a rapid, nonpressure stroke in four separate applications (Fig. 2). The rule of 1 second on and 5 seconds off was followed. A solution of tincture of myrrh and benzoin was applied to the tissue after the incision. T h e teeth were retained with a steel ligature from the buttons to the cleats on the lingual wire (Fig. 3). One month after surgery, the appliances were removed and impressions were made for the analysis of rotation. Three months after surgery another impression was made for the measurement of the amount of relapse.
Electrosurgery 22.7 13.0 20.4 6.2 ll.l 14.68
Percent of relapse Scalpel 20.6 15,0 21.8 29,0 40,0 25.3
Electrosurgery 36.0 14,7 31,2 17.2 16.7 23,1
On the original, rotational, and relapse models a round wire was glued into the groove on the incisal edge of each maxillary second incisor. Another wire was glued onto the midpalatal raphe. Each of the three models for each animal was placed on a prosthetic surveyor and tripod to maintain an identical horizontal plane. While on the surveyor, the casts were photographed on a Linhoff vertical copy stand. From the photographs the original, rotational, and relapse angles were measured with the use of lines superimposed on the midpalatal raphe and the round wire glued to the incisal edges (Fig. 4). The data included the original, rotational, and relapse angles of the scalpel fiberotomy on one maxillary second incisor and the electrosurgical fiberotomy on the contralateral tooth for each of the five dogs. In addition to measuring relapse, this study also measured the sulcus depth and the gingival recession of the experimental teeth. A periodontal probe was used
408
Fricke and Rankine
Am. J. Orthod, Dentofac. Orthop. May 1990
Fig. 4. A, Original model with round wires in the groove on the incisal edges and the midpalatal raphe. B, Model after rotation of the second incisors. C, Model 2 months postretention.
to measure the sulcus depth preoperatively and at i, 2, 3, 4, and 9 weeks postoperatively. Pocket depths were recorded on the rnesial, distal, facial, and lingual surfaces. The amount of gingival recession was determined by means of the shallow horizontal groove in the facial
enamel corresponding to the preoperative level of the free gingival margin. A periodontal probe was used to measure the distance from the horizontal groove to the free gingival margin 1, 2, 3, 4, and 9 weeks after surgery.
Comparison of electrosurgery with conventional fiberotomies
Volume 97
Number 5
DEGREES OF ORTHODONTIC ROTATION
PERCENT OF RELAPSE AFTER 2 MONTHS
90-~
30-
807063.84 63.16 - - - 60-
S. D. =0.09
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S.E.=5. 21 S' E" =8"34 23.1
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Electrosurgery
Fig. 5. Degrees of orthodontic rotation.
RESULTS
The degrees of rotation and relapse and the percent of relapse for each dog are shown in Table I. The range for degrees of rotation was 80.5 ° to 49.2 ° (mean value, 63.1 °) for the teeth treated with scalpel surgery and 88.5 ° to 36.0 ° (mean value, 63.8 °) for the electrosurgically treated teeth (Fig. 5). The ranges for degrees of relapse were 9.6 ° to 19.7 ° (mean value, 15.38 °) for the scalpel group, and 6.2 ° to 22.7 ° (mean value, 14.68 °) for the electrosurgical group. The mean values for amount of relapse were 25.3% for the scalpel surgical technique and 23.1% for the electrosurgical technique (Fig. 6). There was no significant difference between the two groups. One week after surgery the scalpel group showed an average sulcus depth of 4.15 mm. Two weeks after surgery the electrosurgery group showed an average sulcus depth of 4.45 ram. Nine weeks after surgery the scalpel group had an average sulcus depth of 1.75 mm and the electrosurgery group had an average depth of 1.9 ram. There was no significant difference between the two groups (Fig. 7).
\\%\ \\\N
,',,\',) 0
Scalpel Blade
Electrosurgery
Fig. 6. Percent of relapse after 2 months.
The amount of gingival recession was similar in the two groups. Three weeks after surgery the mean for the scalpel group and for the electrosurgery group was 0.7 mm. Nine weeks after surgery the mean for both groups was 0.3 ram; there was no statistical difference (Fig. 8). DISCUSSION
The results of this study indicate that there was no significant difference in orthodontic relapse, gingival recession, and sulcus depth between the teeth treated with scalpel fiberotomies and those treated with electrosurgical fiberotomies. We are unaware of any previous study of wound healing after electrosurgical circumferential fiberotomies. Electrosurgery provided hemostasis by coagulation and sealed the capillary and lymphatic vessels, t3 The completed electromagnetic cycle of the instrument, electrode, dog, and dispersive plate sterilized the tip of
410
Fricke and Rankine
Am. J. Orthod. Dentofac. Orthop. May 1990
SULCUS DEPTH
4.00-
/ 3.20EE ¢.,,
2.40
I. 60 I
I
0.0
2.0
I --
4.0
I
I
I
6.0
8.0
I0.0
Weeks
Fig. 7. Suleus depth.
GINGIVAL RECESSION
---
Scalpel blade Electrosurgery
0.60 E c'-
0.45131
0.30
I
I
1.5
3.0
.....
I
f'
I
I
4.5
6.0
7.5
9.0
Weeks Fig. 8. Gingival recession,
the electrode, thus reducing the potential for infection. ,4 An inherent problem with electrosurgery is the foul odor that is produced. To eliminate the odor, a high-volume evacuation system was employed. Studies of wound healing after electrosurgical excision of gingival tissue compared with that after surgery with conventional periodontal scalpels have yielded conflicting results. Findings reported by Glickman and Imber, '~ Pope et al., 16and Schneider and Zaki iv involving light microscopic tissue studies have ranged from retarded healing to no detectable differences at the electron microscopic level.
Kelly and Harrison n studied differences in healing between surgery with periodontal knives and electrosurgery with regard to gingival regeneration. After 6 weeks, there was a gingival loss of 0.375 mm after the use of periodontal knives compared with a loss of 0.310 mm after the use of electrosurgery. After 8 weeks gingival losses after the use of periodontal knives and electrosurgery were 0.310 mm and 0.115 mm, respectively. In 1970 Glickman and Imber 15conducted biometric and histologic studies to compare the effects of gingival resection with the conventional scalpel and with the
Volume 97 Number 5
Comparison of electrosurge~y with conventionalfiberotomies 411
fully rectified electrosurgical scalpel. Two types of operation were performed; these involved shallow resection in three dogs and deep resection in one dog. After 3 weeks, the shallow resections showed similar results between the electrosurgica//y treated and the scalpeltreated areas in the marginal gingiva and epithelial attachment levels and revealed no histologic alteration in the bone. In the dog with the deep resections, the area treated electrosurgically showed bone necrosis and sequestration, ulceration of the gingiva, and pronounced destruction o f the buccal alveolar plate, whereas the scalpeltreated side showed gingival inflammation, slight recession, and a reduction in bone height. In 1972 Schieda et al. ~9studied the alveolar bone response to electrosurgery and found results diametrically opposite those reported by Glickman and Imber. From the measurements of alveolar bone height and the histologic examination, the electrosurgical areas showed no greater amount of bone loss from the alveolar crest than that found in the control areas. The histologic studies failed to show necrosis, sequestration, or any destruction of the bone. Schieda et al. concluded that the use of electrosurgery in periodontics is safe and effective, even if contact with the bone occurs. Wilhelmsen, Ramfjord, and Blankenship, -~° in 1976, studied the free gingival margin and loss of connective tissue attachment after electrosurgery in four rhesus monkeys. The histometric study resulted in (1) significant recession of the free gingival margin, (2) apical positioning of sulcular epithelium, and (3) loss of some connective tissue attachment. The incision used by Wilhelmsen et al. differed from the incision made in this study in that Wilhelmsen's study involved two incisions. The first incision was made at an acute angle with the tooth, and the second incision was aimed at the bottom of the gingival sulcus. This resulted in resection of a thin wedge of gingival tissue. Conversely, only one parallel incision was made in this study and a wedge of gingival tissue was not resected. There is considerable evidence in the literature supporting both sides of the controversy. T h e purpose of this study was to determine the amount of relapse that occurs after circumferential supracrestal fiberotomies with electrosurgery versus the amount of relapse after circumferential supracrestal fiberotomies with conventional scalpel blades. Measurements of gingival recession and pocket depth served merely as indicators of healing. A more detailed histologic study may be necessary to determine the responses of the gingiva and alveolar bone to electrosurgery in circumferential supracrestal fiberotomies. A future study, in addition, should assess connective tissue reattachment after cem e n t u m contact with an electrode.
An obvious limitation of this study was that the experimental model was the dog, whose gingival fibers vary from those o f human beings. For example, the proportions of elastic and oxytalan fibers are similar in human beings and rhesus monkeys but different in dogs. 2j Therefore, a consecutive study involving the rhesus monkey is warranted. There is controversy over whether the amount of rotational relapse is influenced by the severity of the initial rotation. Swanson, Riedel, and D ' A n n a ~2 reported a direct relationship between relapse and initial rotation. Conversely, Boese ~ and Brain ~° found that the percentage of relapse was not directly related to the degree of initial rotation. The present study agrees with the latter findings, as the severely rotated teeth did not predictably exhibit more relapse than the moderately rotated teeth. For example, in dog No. 5, the tooth rotated 49.2 ° showed a 40% relapse, whereas the tooth rotated 66.3 ° showed a 16.7% relapse. Dog No. 4 demonstrated the opposite trend, in that the tooth rotated 56.8 ° relapsed 29% and the tooth rotated 36 ° relapsed 17.2%. In dog No. 1 similarly rotated teeth exhibited different amounts of relapse. There was no correlation between the amount of rotation and the amount of relapse. In conclusion, the results of this study indicate there was no significant difference in orthodontic relapse, gingival recession, and sulcus depth between the teeth treated with scalpel fiberotomies and those treated with electrosurgical fiberotomies. The data from this study demonstrate that electrosurgery was as effectiv'e as the conventional scalpel blade procedures in circumferential fiberotomies in dogs. We would like to express our gratitude to Dr. James Harrison for his assistance.
REFERENCES
1. Thompson HE. Orthodontic relapses analyzed in a study of connective tissue fibers. AMJ ORTHOD1959;¢5:93-109. 2. Edwards JG. A study of the periodontium during orthodontic rotation of teeth. AM J ORTHOD1968;54:441-61. 3. Reitan K. Tissue behavior during orthodontic tooth movement. AM J ORTHOD1960;46:881-900. 4. Reitan K. Tissue rearrangement during retention of orthodontically rotated teeth. Angle Orthod 1959;29:105-i3. 5. Kaplan RG. Cliniea~ experiences with circumferential supracrestal fiberotomy. AM J ORTHOD1976;70:146-53. 6. Edwards JG. A surgical procedure to eliminate rotational relapse. AM J ORTHOD1970;57:35-46.
7. Pinson RR, Strahan JD. The effect on the relapse of orthodontically rotated teeth of surgical division of the gingival fibresperieision. Br I Orthod 1973;1:87-91. 8. Wiser GM. Resection of the supra-alveolar fibers and the retention of orthodontically rotated teeth [Abstract]. AM J ORTI-IOD 1966;52:855-6, 9. Edwards .1(3. A long-term prospective evaluation of the clrcum-
412 Fricke and Rankine
10.
11.
12. 13. 14. 15.
16. 17.
ferentia[ supracrestal fiberotomy in alleviating orthodontic relapse. AM J ORa~ODDENTOFACORTnOP1988;93:380-7. Brain WE. The effect of surgical transection of free gingival fibers on the regression of orthodontically rotated teeth in the dog. AM J ORanaOD1969;55:50-70. Boese LR. Increased stability of orthodontically rotated teeth following gingivectomyin Macaca nemestrina. AM J ORTHOD 1969;56:273-90. Kelly WJ, Harrison JD. Tissue dilation during multiple cast techniques. Dent Clio North Am 1982;26:759-80. Conroy CW. Currentconcepts of periodontal therapy using electrosurgery. Dent Clin North Am 1982;26:873-90. Young AT, Malone WFP. Clinical application of research in electrosurgery. Dent Clin North Am 1982;26:835-54. Glickman I, Imber TR. Comparison of gingival resection with electrosurgery and periodontalknives: a biometricand histologic study. J Periodontol 1970;41:142-8. Pope JW, Gargiulo AW, Staffileno H, Levy S. Effect of electrosurgery on wound healing in dogs. Pefiodontics 1968;6:30-7. Schneider A, Zaki AE. Gingival wound healing following ex-
Am. J. Orthod. Dentofac. Orthop. May 1990
18. 19. 20.
21.
22.
perimentalelectrosurgery:an electron microseopic investigation. J Perlodontol 1974;45:685-94. OringerM/. Electrosurgeryin dentistry.Philadelphia: WB Saunders, 1975:729-31. Schieda JD, DeMarco T, Johnson LE. Alveolar bone response to electrosurgiealscalpel. J Pefiodontol 1972;43:225. WilhelmsenNR, RamfjordSP, BlankenshipJR. Effects of eleca'osurgery on gingival attachment of rhesus monkeys. J Pefiodontol 1976;47:160-70. FullmerHM. A comparativehistochemicalstudy of elastic, preelastic and oxytalan connective tissue fibers. J Histochem Cytochem 1960;8:290-5. Swanson WD, Riedcl RA, D'Anna JA. Postretention study: incidence and stability of rotated teeth in humans. Angle Orthod 1975;45:198-203,
Reprint requests to: Dr. Laurie Lee Fficke
40 Shady Oak Dr. Covington, LA 70433
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The relapse tendency of orthodontically rotated teeth after electrosurgical circumferential fiberotomies and after conventional scalpel blade surgical procedures was demonstrated with a split-mouth procedure involving the maxillary second incisors of five mongrel dogs. The second incisors were rotated orthodontically an average of 63.5 ° over a 4-month period. Electrosurgical circumferential fiberotomies were performed on the designated second incisors, and circumferential fiberotomies with a scalpel blade were performed on the contralateral incisors. The teeth were retained for 1 month and relapse was measured 2 months postretention. Wound healing was demonstrated by measurement of sulcus depths and facial gingival recession preoperatively and at 1, 2, 3, 4, and 9 weeks after surgery. In both groups, the sufcus depths had decreased about 2 mm and the facial gingiva had receded 0.3 mrn 9 weeks after surgery. Two months postretention there was an average 25% relapse in the teeth treated by means of a circumferential fiberotomy with a scalpel blade compared to an average 23% relapse in those treated by means of a circumferential fiberotomy with electrosurgery. No significant difference was seen between the two techniques. (AM J ORTHOD DENTOFACORTHOP 1990;97:405-12.)
M a i n t e n a n c e of the correction of severely rotated teeth is a concern in orthodontic therapy. A significant cause of relapse is thought to be the gingival and transseptal fibers, which are stretched and twisted as the tooth is rotated. 1-4To reduce the potential relapse, a circumferential supracrestal fiberotomy is performed. Conventionally, a scalpel blade is inserted into the depth of the gingival sulcus to sever the twisted gingival fibers from the rotated tooth? The purpose of this study was to compare the results of fiberotomies performed by means of electrosurgery and fiberotomies performed by the conventional scalpel blade procedure. The specific aims were to compare (I) amount of relapse, (2) amount of gingival recession, and (3) sulcus depth. The literature offers substantial indication that circumferential fiberotomies significantly reduce relapse following orthodontic rotation? "9 For example, Pinson and Strahan 7demonstrated, in human patients, that after 23 weeks of retention a mean relapse of 56.5% of the original rotation occurred where no fiberotomies had been performed. The teeth on which fiberotomies were
From Louisiana State University School of Dentistry. *Postgraduate student, Department of Orthodontics, **Assistant Professor, Department of Orthodontics. 8/1112599
performed displayed a reduced relapse of 20% of the original rotation after 16 to 28 weeks of retention. In dogs, fiberotomies significantly reduce the amount of relapse. Wiser 8 reported a mean 11.2% relapse after fiberotomy compared with a mean 43.8% relapse when no fiberotomy was performed. Brain '° reported a mean 1.1% relapse after fiberotomy compared with a mean 43.3% in the control. The literature supports the belief that fiberotomies significantly reduce relapse following orthodontic rotation. However, in a questionnaire sent to 1000 orthodontists in the United States, 75% of the respondents stated that they did not use fiberotomies? The lack of clinical acceptance despite the demonstrated advantage suggests to us the need to consider an alternate technique that may be more clinically acceptable. MATERIAL AND METHODS A split-mouth procedure involving the maxillary second incisors of five mongrel dogs was used. The maxillary second incisors were selected as the experimental teeth because comparable methods were used in previous studies on dogs and because the dimensions of the tooth and alveolar structure are similar to those of human beings. The procedure involved rotation of the maxillary incisors followed by a circumferential fiberotomy with a scalpel blade on one side of the arch 405
406
Fricke and Rankine
Am. J. Orthod. Dent~?~lc, Orthop.
May 1990
Fig. 1. Labiolingual appliance with elastic chain to rotate second incisors.
C Fig. 2. Electrode passed around tooth with four separate applications.
and an eleetrosurgical circumferential fiberotomy on the contralateral side. Each dog was sedated, and a shallow groove was made on the facial enamel at the crest of the marginal gingiva as a reference for measurement of the amount of gingival recession. Another groove was made on the incisal edge to help measure the amount of rotation and relapse. To prevent occlusal interference with the appliance, the mandibular incisors were extracted and the mandibular canines were reduced to the gingival crest after pulP0tomies were performed. Two impressions were made, and from the stone casts a specially designed labiolingual appliance was fabricated and prerotational measurements were made. The appliance consisted of band material adapted to the canines and the third incisors. Perforations were
made on each band to allow for mechanical retention. One 0.036 inch round wire from canine to canine was soldered to the labial surface of the bands and another to the lingual surface. Small cleats were welded to the wires. One week later the appliances were bonded to the third incisors and the maxillary canines. Orthodontic buttons were bonded to the labial and lingual surfaces of the maxillary second incisors. Elastic chains were engaged from each button to a cleat on the labiolingual appliance to create a faciodistal-linguomesial rotational force (Fig. 1). The dogs were kept on a soft diet for the duration of the experiment and were seen once a week for 3 months so that hygiene could be maintained, the elastics could be changed, and the stability of the appliances could be checked. After 16 weeks of orthodontic rotation, scalpel circumferential fiberotomies were performed on one second incisor and electrosurgical circumferential fiberotomies were performed on the contralateral incisor. Surgery was performed before retention, as described in studies by Edwards, 9 Brain, ~° and Boese. ~t Immediately before the fiberotomies were performed, the sulcus depth was measured on the mesial, distal, facial, and lingual surfaces of each tooth. The technique for the scalpel fiberotomies was that described by Edwards. 6 A Bard-Parker blade was inserted to a depth approximately 3 mm below the crest of alveolar bone, severing the fibers surrounding the tooth. The technique for the electrosurgical fiberotomies was similar to the method for tissue dilation reported by Kelly and Harrison.t2 As described in their study,
Comparison of electrosurgery with conventional fiberotomies 407
Volume 97 Number 5
Fig. 3. Labiolingual appliance during retention. Ligature wire was tied from the buttons on the second incisors to the cleats on the lingual wire.
Table I. Relapse Degrees of rotation Dog 1 2 3 4 5 Mean
Scalpel 65.5 63.8 80,5 56,8 49.2 63.16
Electrosurgery 63,0 88.5 65.4 36,0 66,3 63.84
Degrees of relapse Scalpel 13,5 9.6 17.6 16.5 19.7 15.38
an Ellman Dento Surg unit (Ellman Dental Mfg. Co., Hewlett, N.Y.) was used and a fully rectified surgical current was selected, since this current provides coagulation as well as incision. A passive plate was placed under the dog's shoulders. A straight-wire electrode was held parallel and next to the tooth in the gingival sulcus and passed around the tooth approximately 1 to 2 mm below the epithelial attachment with a rapid, nonpressure stroke in four separate applications (Fig. 2). The rule of 1 second on and 5 seconds off was followed. A solution of tincture of myrrh and benzoin was applied to the tissue after the incision. T h e teeth were retained with a steel ligature from the buttons to the cleats on the lingual wire (Fig. 3). One month after surgery, the appliances were removed and impressions were made for the analysis of rotation. Three months after surgery another impression was made for the measurement of the amount of relapse.
Electrosurgery 22.7 13.0 20.4 6.2 ll.l 14.68
Percent of relapse Scalpel 20.6 15,0 21.8 29,0 40,0 25.3
Electrosurgery 36.0 14,7 31,2 17.2 16.7 23,1
On the original, rotational, and relapse models a round wire was glued into the groove on the incisal edge of each maxillary second incisor. Another wire was glued onto the midpalatal raphe. Each of the three models for each animal was placed on a prosthetic surveyor and tripod to maintain an identical horizontal plane. While on the surveyor, the casts were photographed on a Linhoff vertical copy stand. From the photographs the original, rotational, and relapse angles were measured with the use of lines superimposed on the midpalatal raphe and the round wire glued to the incisal edges (Fig. 4). The data included the original, rotational, and relapse angles of the scalpel fiberotomy on one maxillary second incisor and the electrosurgical fiberotomy on the contralateral tooth for each of the five dogs. In addition to measuring relapse, this study also measured the sulcus depth and the gingival recession of the experimental teeth. A periodontal probe was used
408
Fricke and Rankine
Am. J. Orthod, Dentofac. Orthop. May 1990
Fig. 4. A, Original model with round wires in the groove on the incisal edges and the midpalatal raphe. B, Model after rotation of the second incisors. C, Model 2 months postretention.
to measure the sulcus depth preoperatively and at i, 2, 3, 4, and 9 weeks postoperatively. Pocket depths were recorded on the rnesial, distal, facial, and lingual surfaces. The amount of gingival recession was determined by means of the shallow horizontal groove in the facial
enamel corresponding to the preoperative level of the free gingival margin. A periodontal probe was used to measure the distance from the horizontal groove to the free gingival margin 1, 2, 3, 4, and 9 weeks after surgery.
Comparison of electrosurgery with conventional fiberotomies
Volume 97
Number 5
DEGREES OF ORTHODONTIC ROTATION
PERCENT OF RELAPSE AFTER 2 MONTHS
90-~
30-
807063.84 63.16 - - - 60-
S. D. =0.09
25.3. 25-
S.E.=5. 21 S' E" =8"34 23.1
20-
x.~l
,x,,\-,,l ,\'q
15'
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Electrosurgery
Fig. 5. Degrees of orthodontic rotation.
RESULTS
The degrees of rotation and relapse and the percent of relapse for each dog are shown in Table I. The range for degrees of rotation was 80.5 ° to 49.2 ° (mean value, 63.1 °) for the teeth treated with scalpel surgery and 88.5 ° to 36.0 ° (mean value, 63.8 °) for the electrosurgically treated teeth (Fig. 5). The ranges for degrees of relapse were 9.6 ° to 19.7 ° (mean value, 15.38 °) for the scalpel group, and 6.2 ° to 22.7 ° (mean value, 14.68 °) for the electrosurgical group. The mean values for amount of relapse were 25.3% for the scalpel surgical technique and 23.1% for the electrosurgical technique (Fig. 6). There was no significant difference between the two groups. One week after surgery the scalpel group showed an average sulcus depth of 4.15 mm. Two weeks after surgery the electrosurgery group showed an average sulcus depth of 4.45 ram. Nine weeks after surgery the scalpel group had an average sulcus depth of 1.75 mm and the electrosurgery group had an average depth of 1.9 ram. There was no significant difference between the two groups (Fig. 7).
\\%\ \\\N
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Electrosurgery
Fig. 6. Percent of relapse after 2 months.
The amount of gingival recession was similar in the two groups. Three weeks after surgery the mean for the scalpel group and for the electrosurgery group was 0.7 mm. Nine weeks after surgery the mean for both groups was 0.3 ram; there was no statistical difference (Fig. 8). DISCUSSION
The results of this study indicate that there was no significant difference in orthodontic relapse, gingival recession, and sulcus depth between the teeth treated with scalpel fiberotomies and those treated with electrosurgical fiberotomies. We are unaware of any previous study of wound healing after electrosurgical circumferential fiberotomies. Electrosurgery provided hemostasis by coagulation and sealed the capillary and lymphatic vessels, t3 The completed electromagnetic cycle of the instrument, electrode, dog, and dispersive plate sterilized the tip of
410
Fricke and Rankine
Am. J. Orthod. Dentofac. Orthop. May 1990
SULCUS DEPTH
4.00-
/ 3.20EE ¢.,,
2.40
I. 60 I
I
0.0
2.0
I --
4.0
I
I
I
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8.0
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Fig. 7. Suleus depth.
GINGIVAL RECESSION
---
Scalpel blade Electrosurgery
0.60 E c'-
0.45131
0.30
I
I
1.5
3.0
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I
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the electrode, thus reducing the potential for infection. ,4 An inherent problem with electrosurgery is the foul odor that is produced. To eliminate the odor, a high-volume evacuation system was employed. Studies of wound healing after electrosurgical excision of gingival tissue compared with that after surgery with conventional periodontal scalpels have yielded conflicting results. Findings reported by Glickman and Imber, '~ Pope et al., 16and Schneider and Zaki iv involving light microscopic tissue studies have ranged from retarded healing to no detectable differences at the electron microscopic level.
Kelly and Harrison n studied differences in healing between surgery with periodontal knives and electrosurgery with regard to gingival regeneration. After 6 weeks, there was a gingival loss of 0.375 mm after the use of periodontal knives compared with a loss of 0.310 mm after the use of electrosurgery. After 8 weeks gingival losses after the use of periodontal knives and electrosurgery were 0.310 mm and 0.115 mm, respectively. In 1970 Glickman and Imber 15conducted biometric and histologic studies to compare the effects of gingival resection with the conventional scalpel and with the
Volume 97 Number 5
Comparison of electrosurge~y with conventionalfiberotomies 411
fully rectified electrosurgical scalpel. Two types of operation were performed; these involved shallow resection in three dogs and deep resection in one dog. After 3 weeks, the shallow resections showed similar results between the electrosurgica//y treated and the scalpeltreated areas in the marginal gingiva and epithelial attachment levels and revealed no histologic alteration in the bone. In the dog with the deep resections, the area treated electrosurgically showed bone necrosis and sequestration, ulceration of the gingiva, and pronounced destruction o f the buccal alveolar plate, whereas the scalpeltreated side showed gingival inflammation, slight recession, and a reduction in bone height. In 1972 Schieda et al. ~9studied the alveolar bone response to electrosurgery and found results diametrically opposite those reported by Glickman and Imber. From the measurements of alveolar bone height and the histologic examination, the electrosurgical areas showed no greater amount of bone loss from the alveolar crest than that found in the control areas. The histologic studies failed to show necrosis, sequestration, or any destruction of the bone. Schieda et al. concluded that the use of electrosurgery in periodontics is safe and effective, even if contact with the bone occurs. Wilhelmsen, Ramfjord, and Blankenship, -~° in 1976, studied the free gingival margin and loss of connective tissue attachment after electrosurgery in four rhesus monkeys. The histometric study resulted in (1) significant recession of the free gingival margin, (2) apical positioning of sulcular epithelium, and (3) loss of some connective tissue attachment. The incision used by Wilhelmsen et al. differed from the incision made in this study in that Wilhelmsen's study involved two incisions. The first incision was made at an acute angle with the tooth, and the second incision was aimed at the bottom of the gingival sulcus. This resulted in resection of a thin wedge of gingival tissue. Conversely, only one parallel incision was made in this study and a wedge of gingival tissue was not resected. There is considerable evidence in the literature supporting both sides of the controversy. T h e purpose of this study was to determine the amount of relapse that occurs after circumferential supracrestal fiberotomies with electrosurgery versus the amount of relapse after circumferential supracrestal fiberotomies with conventional scalpel blades. Measurements of gingival recession and pocket depth served merely as indicators of healing. A more detailed histologic study may be necessary to determine the responses of the gingiva and alveolar bone to electrosurgery in circumferential supracrestal fiberotomies. A future study, in addition, should assess connective tissue reattachment after cem e n t u m contact with an electrode.
An obvious limitation of this study was that the experimental model was the dog, whose gingival fibers vary from those o f human beings. For example, the proportions of elastic and oxytalan fibers are similar in human beings and rhesus monkeys but different in dogs. 2j Therefore, a consecutive study involving the rhesus monkey is warranted. There is controversy over whether the amount of rotational relapse is influenced by the severity of the initial rotation. Swanson, Riedel, and D ' A n n a ~2 reported a direct relationship between relapse and initial rotation. Conversely, Boese ~ and Brain ~° found that the percentage of relapse was not directly related to the degree of initial rotation. The present study agrees with the latter findings, as the severely rotated teeth did not predictably exhibit more relapse than the moderately rotated teeth. For example, in dog No. 5, the tooth rotated 49.2 ° showed a 40% relapse, whereas the tooth rotated 66.3 ° showed a 16.7% relapse. Dog No. 4 demonstrated the opposite trend, in that the tooth rotated 56.8 ° relapsed 29% and the tooth rotated 36 ° relapsed 17.2%. In dog No. 1 similarly rotated teeth exhibited different amounts of relapse. There was no correlation between the amount of rotation and the amount of relapse. In conclusion, the results of this study indicate there was no significant difference in orthodontic relapse, gingival recession, and sulcus depth between the teeth treated with scalpel fiberotomies and those treated with electrosurgical fiberotomies. The data from this study demonstrate that electrosurgery was as effectiv'e as the conventional scalpel blade procedures in circumferential fiberotomies in dogs. We would like to express our gratitude to Dr. James Harrison for his assistance.
REFERENCES
1. Thompson HE. Orthodontic relapses analyzed in a study of connective tissue fibers. AMJ ORTHOD1959;¢5:93-109. 2. Edwards JG. A study of the periodontium during orthodontic rotation of teeth. AM J ORTHOD1968;54:441-61. 3. Reitan K. Tissue behavior during orthodontic tooth movement. AM J ORTHOD1960;46:881-900. 4. Reitan K. Tissue rearrangement during retention of orthodontically rotated teeth. Angle Orthod 1959;29:105-i3. 5. Kaplan RG. Cliniea~ experiences with circumferential supracrestal fiberotomy. AM J ORTHOD1976;70:146-53. 6. Edwards JG. A surgical procedure to eliminate rotational relapse. AM J ORTHOD1970;57:35-46.
7. Pinson RR, Strahan JD. The effect on the relapse of orthodontically rotated teeth of surgical division of the gingival fibresperieision. Br I Orthod 1973;1:87-91. 8. Wiser GM. Resection of the supra-alveolar fibers and the retention of orthodontically rotated teeth [Abstract]. AM J ORTI-IOD 1966;52:855-6, 9. Edwards .1(3. A long-term prospective evaluation of the clrcum-
412 Fricke and Rankine
10.
11.
12. 13. 14. 15.
16. 17.
ferentia[ supracrestal fiberotomy in alleviating orthodontic relapse. AM J ORa~ODDENTOFACORTnOP1988;93:380-7. Brain WE. The effect of surgical transection of free gingival fibers on the regression of orthodontically rotated teeth in the dog. AM J ORanaOD1969;55:50-70. Boese LR. Increased stability of orthodontically rotated teeth following gingivectomyin Macaca nemestrina. AM J ORTHOD 1969;56:273-90. Kelly WJ, Harrison JD. Tissue dilation during multiple cast techniques. Dent Clio North Am 1982;26:759-80. Conroy CW. Currentconcepts of periodontal therapy using electrosurgery. Dent Clin North Am 1982;26:873-90. Young AT, Malone WFP. Clinical application of research in electrosurgery. Dent Clin North Am 1982;26:835-54. Glickman I, Imber TR. Comparison of gingival resection with electrosurgery and periodontalknives: a biometricand histologic study. J Periodontol 1970;41:142-8. Pope JW, Gargiulo AW, Staffileno H, Levy S. Effect of electrosurgery on wound healing in dogs. Pefiodontics 1968;6:30-7. Schneider A, Zaki AE. Gingival wound healing following ex-
Am. J. Orthod. Dentofac. Orthop. May 1990
18. 19. 20.
21.
22.
perimentalelectrosurgery:an electron microseopic investigation. J Perlodontol 1974;45:685-94. OringerM/. Electrosurgeryin dentistry.Philadelphia: WB Saunders, 1975:729-31. Schieda JD, DeMarco T, Johnson LE. Alveolar bone response to electrosurgiealscalpel. J Pefiodontol 1972;43:225. WilhelmsenNR, RamfjordSP, BlankenshipJR. Effects of eleca'osurgery on gingival attachment of rhesus monkeys. J Pefiodontol 1976;47:160-70. FullmerHM. A comparativehistochemicalstudy of elastic, preelastic and oxytalan connective tissue fibers. J Histochem Cytochem 1960;8:290-5. Swanson WD, Riedcl RA, D'Anna JA. Postretention study: incidence and stability of rotated teeth in humans. Angle Orthod 1975;45:198-203,
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