- Email: [email protected]
Surgical positioning of maxillary canines
Report of a Case J. J. Williamson, Y.D.Sc., Ijental
School, Unkemity
P.D.S.lW.S.,*
Perth,
Western Australia
of Western Australia.
A symposium on transplantation, replantation, and surgical positioning of Irepositioning teeth,l Holland2 reported “a high incidence of success with a technique of certain unerupted and/or impacted teeth. ” In this technique, a N
new socket is made in the alveolar process into which the surgically exposed unerupted tooth can be rotated or guided into an erupted position with its long axis in good alignment. There is fairly general agreement? that, ideally, root formation should be no more than five-sixths complete, since revaseularization of the pulp is unlikely if the apical foramen is further closed. Where root formation is complete, the technique is modified and movement of the tooth is restricted to tipping around the apex as rotation center in an attempt to preserve the blood supply to the pulp. Baden observes that surgical positioning of teeth is “fraught with a certain percentage of failures.” The following case is reported to emphasize that surgical positioning should be approached with circumspection and that even “success” can be limited to a relatively short period. CASE RRPCRT The patient, a 12-year-old girl attending the Perth Dental Hospital, was referred from the Orthodontic Department for surgical exposure of the maxillary canines. AU permanent teeth were erupted with the exception of the four third molars and the maxillary canines. The maxillary deciduous canines were present, and there was ample room in the arch for the permanent canines, which radiographs showed were lying on the palatal aspect of the arch, each with its crown closely related to the root of the central incisor and with a horizontal inclination of about 45 degrees (Figs. 1, 2, and 3). It was considered that in this position the maxillary canines were unlikely to erupt of their own accord and that surgical exposure to assist eruption was indicated. On March 13, 1961, with the patient under sedation and local anesthesia, a palatal flap was raised and the crowns of the maxillary canines were uncovered. The crowns were deep and lying in such a position that eruption seemed most unlikely (Fig. 4) ; therefore, the decision was made to reposition them. The deciduous canines were extracted and the bone between the permanent canines and the deciduous sockets was removed. A gouge was used to expose the greater part *Senior Lecturer in
Oral
Medicine
and
Oral
Surgery,
289
University
of
Western
Australia.
Fig. Z.-Preoperative Fig. 3.-Preoperative
radiograh radiograph
of upper right canine. of upper left canine.
Volume 17 Number 3
SURGICAL
POSITIONING
OF MAXILLARY
CANINES
291
of the distal and pdatal aspects of the canine roots and the canines were then loosened and turned toward the deciduous canine sockets. To minimize trauma to the pulpal vessels, each tooth was tilted around its apex as rotation center, and no attempt waa made to bring it to the level of the occlusal plane. The left canine wedged nicely in its new poeition, but the right canine was loose and without doubt its apical vessels had ruptured. The palatal flap was trimmed free of each canine crown and closed (Fig. 5). An impression w&9 taken for the construction of a metal cap splint, and a zinc oxide pack was sutured over each canine. On the following clay the packs were removed and the splint waa cemented over all maxillary teeth. When the splint was removed on May 15, 1961, both canines were quite firm, Six months after the opemtion (on Sept. 25, 1961) both teeth were of good color and gave a positive response to teats with the electric pulp tester, but dental radiographs showed a lack of definition between tooth root and periodontal membrane. Further radiographs on Jan. 15, 1962, showed partial obliteration of the pulp and definite radiolucency on the clistolingual aspect of the roots of both teeth (Figs. 6 and 7). There had been no change in position of the teeth since they were repositioned. Since it was fairly evident that ankylosia would prevent further eruption, the caninea lvere extracted.
he
the were
ved.
i1.S.. O.M. & O.P. March. 1964
Fig. 6.
Fig. 7.
Fig. B.-Radiograph of of the periodontal membrane is obvious resorption on the Fig. ‘I.-Radiograph of months postoperatively.
upper right canine taken 10 months postoperatively. The shadow is indefinite. the pulp cavity has been partly obliterated, and there distolingual aspect. upper left canine showing an advanced degree of resorption 10
1n each tooth the histologic picture was similar (Figs. 8 and 9). A resorptive process, apparently commencing from the lingual surface of the root, had removed an extensive amount of tooth substance and evidently was still active in many areas where osteoclasts abutted on Howship’s lacuna0 in dcntine (Fig. 10). The resorbed arw contained a fibrous tissue in which considerable bone, of both woven and lamellar type, had been laid down. In some places there was fusion of bone to dentine. Examination of serial sections of both teeth revealed Fig. B.-Section of upper right canine showing quite advanced resorption and bone formation within the resorbed area. The section does not paas through the root canal but shows deposited on its walls. (Hematoxylin and eosin stain. some of the calcifled “osteodentine” Magnification. x8 ; reduced ]k.) Fig. 9.-Section of upper left canine showing extensive resorption and bony replacement of tooth substance. (Hematoxylin and eosin stain. Magnification. x8 ; reduced % 1 Fig. lO.-Osteoclastlc resorption of dentine is evident. In places, “osteodentine” haa been laid down on previously resorbed areas of dentine. Woven bone is present within a flbroblastic tissue which is lightly infiltrated with round cells. (Hematoxylin and eosin stain. Magnification. x105 ; reduced $4.)
Volume 17 Number 3
SURGTCAL
Fig.
POSITIONING
OF MAXILLARY
Fig.
8.
Fig. Figs.
8 to lo.-(For
293
CANINES
9.
10.
legends, see opposite
gage.)
that the pulp cavity, although almost completely obliterated 11y ‘ i osteodent ino ’ ’ laitl do\Vn on the walls, contained a fibrous tissue which communic*atted with t.hc periapic-a1 t.issuc through the apical foramen and with the fibrous tissue in tht! area of rc++orption. A vrry mild iniiltra~t! of round cells was scattcrrd diffusely throughout the fibrous tissue, but no plasma. ~11s ww sceu. Coraclzlsion: External root resorption and ankylosis of the maxillary canines.
COMMENT
It is noteworthy that, even though the apical vessels supplying the right maxillary canine were, without doubt, ruptured at the time of the operation, pulpal degeneration rather than pulpal necrosis resulted. It would seem that a similar pulpal reaction had developed in both teeth, and the changes conform with the findings of Agnew and FongE in experimental transplantation in the rhesus monkey. It is considered that temporary deprivation of nuarition to the more specialized cells results in a degenerative change. In some inst.ances partial regeneration of odontoblasts may occur, but generally the fibroblast is the cell which survives and extensive calcification is often observed in a fibrillar type of scar tissue lining the surrounding dentinal wall. Holland,2 who mentions t.hat he has used the “technique of surgical orthodontics” on more than 300 teeth, published det.ailed records of eight cases,’ the longest postoperative follow-up in any one case being only 10 months. He observed calcification in the pulp canals bu6 resorption in one case only, and this on the dist.al aspect of an upper left canine 7 months after surgical intervention. However, external root resorption of varying degree is a fairly constant finding among transplant.ed and replanted teeth and, to quote Thorna,* “the ultimate fate of replant.ed teeth is resorption of the tooth with replacement of the dental tissue by bone.” The teet,h are not retained permanently, their “life” being dependent on the rate and extent of the resorptive process. The cause of the resorption is not known. External root resorption is often associated with new bone formation resulting in ankylosis. The ankylosis may be a true ankylosis from union of bone and tooth substance, or it may bc due to a dovetailing of bone laid down in areas of resorpDion. Whatever the type of ankylosis, further eruption of a tooah is highly unlikely: t.he positioning of a toot.h so that it is short of the occlusal plane may therefore result in its failure to erupt completely. SUMMARY
A case in which the technique of surgical positioning was carried out, OII maxillary canines in a 12-year-old girl has been reported. Nine months postoperatively each tooth showed advanced resorption of its roots and was cxtracted. Histologically, each tooth showed ankylosis. tElc
REFERENCES 1. Symposium:
Transplantation,
Replantation
and Surgical
ORAL MED. & ORAL PATH. 9: 3-140, 1956.
Positioning
of Teeth, ORAL SURG.,
2. Holland, D. J.: The Surgical Positioning of Unerupted Impacted Teeth tics), ORAL Smw., OIUL MED. & ORAL PATH. 9: 130, 1956.
(Surgical
Orthodon-
Volume17 Number3
SURGICAL
POSITIONING
OF MAXTLLARY
CANINES
295
3. Villaseca. H. Rodolfo: Autoaenous Transulantation of an Imuacted Cuwid to the First Bikpid Alveolus for Orthodontic Purposes : Case Repor%,,D. Abat: 3: 144, 1953. 4. Thoma. K. H.: Sureieal Positionine: of Erupted Teeth in Torso-Occlusion, OILAL SURG..ORAL LED. & ORAL~PATH.9: 125, i956. * 5. Baden, Ernest: Surgical Management of Unerupted Canines and Premolars, ORAL SURQ., ORAL MED. & ORAL PATH. 9: 141, 1956. 6. Agnew, R. G., and Fong, C. C.: Histologic Studies in Experimental Transplantation of Teeth, ORAL Sm.&, ORAL MED. $ OrmA PATH. 9: 18, 1956. 7. Holland, D. J.: A Teachnique of Surgical Orthodontics, Am. J. Orthodontics 41: 27, 1955. 8. Thoma, K. H.: Oral Surgery, ed. 3, St. Louis, 1958, The C. V. Mosby Company, p. 420.
School, Unkemity
P.D.S.lW.S.,*
Perth,
Western Australia
of Western Australia.
A symposium on transplantation, replantation, and surgical positioning of Irepositioning teeth,l Holland2 reported “a high incidence of success with a technique of certain unerupted and/or impacted teeth. ” In this technique, a N
new socket is made in the alveolar process into which the surgically exposed unerupted tooth can be rotated or guided into an erupted position with its long axis in good alignment. There is fairly general agreement? that, ideally, root formation should be no more than five-sixths complete, since revaseularization of the pulp is unlikely if the apical foramen is further closed. Where root formation is complete, the technique is modified and movement of the tooth is restricted to tipping around the apex as rotation center in an attempt to preserve the blood supply to the pulp. Baden observes that surgical positioning of teeth is “fraught with a certain percentage of failures.” The following case is reported to emphasize that surgical positioning should be approached with circumspection and that even “success” can be limited to a relatively short period. CASE RRPCRT The patient, a 12-year-old girl attending the Perth Dental Hospital, was referred from the Orthodontic Department for surgical exposure of the maxillary canines. AU permanent teeth were erupted with the exception of the four third molars and the maxillary canines. The maxillary deciduous canines were present, and there was ample room in the arch for the permanent canines, which radiographs showed were lying on the palatal aspect of the arch, each with its crown closely related to the root of the central incisor and with a horizontal inclination of about 45 degrees (Figs. 1, 2, and 3). It was considered that in this position the maxillary canines were unlikely to erupt of their own accord and that surgical exposure to assist eruption was indicated. On March 13, 1961, with the patient under sedation and local anesthesia, a palatal flap was raised and the crowns of the maxillary canines were uncovered. The crowns were deep and lying in such a position that eruption seemed most unlikely (Fig. 4) ; therefore, the decision was made to reposition them. The deciduous canines were extracted and the bone between the permanent canines and the deciduous sockets was removed. A gouge was used to expose the greater part *Senior Lecturer in
Oral
Medicine
and
Oral
Surgery,
289
University
of
Western
Australia.
Fig. Z.-Preoperative Fig. 3.-Preoperative
radiograh radiograph
of upper right canine. of upper left canine.
Volume 17 Number 3
SURGICAL
POSITIONING
OF MAXILLARY
CANINES
291
of the distal and pdatal aspects of the canine roots and the canines were then loosened and turned toward the deciduous canine sockets. To minimize trauma to the pulpal vessels, each tooth was tilted around its apex as rotation center, and no attempt waa made to bring it to the level of the occlusal plane. The left canine wedged nicely in its new poeition, but the right canine was loose and without doubt its apical vessels had ruptured. The palatal flap was trimmed free of each canine crown and closed (Fig. 5). An impression w&9 taken for the construction of a metal cap splint, and a zinc oxide pack was sutured over each canine. On the following clay the packs were removed and the splint waa cemented over all maxillary teeth. When the splint was removed on May 15, 1961, both canines were quite firm, Six months after the opemtion (on Sept. 25, 1961) both teeth were of good color and gave a positive response to teats with the electric pulp tester, but dental radiographs showed a lack of definition between tooth root and periodontal membrane. Further radiographs on Jan. 15, 1962, showed partial obliteration of the pulp and definite radiolucency on the clistolingual aspect of the roots of both teeth (Figs. 6 and 7). There had been no change in position of the teeth since they were repositioned. Since it was fairly evident that ankylosia would prevent further eruption, the caninea lvere extracted.
he
the were
ved.
i1.S.. O.M. & O.P. March. 1964
Fig. 6.
Fig. 7.
Fig. B.-Radiograph of of the periodontal membrane is obvious resorption on the Fig. ‘I.-Radiograph of months postoperatively.
upper right canine taken 10 months postoperatively. The shadow is indefinite. the pulp cavity has been partly obliterated, and there distolingual aspect. upper left canine showing an advanced degree of resorption 10
1n each tooth the histologic picture was similar (Figs. 8 and 9). A resorptive process, apparently commencing from the lingual surface of the root, had removed an extensive amount of tooth substance and evidently was still active in many areas where osteoclasts abutted on Howship’s lacuna0 in dcntine (Fig. 10). The resorbed arw contained a fibrous tissue in which considerable bone, of both woven and lamellar type, had been laid down. In some places there was fusion of bone to dentine. Examination of serial sections of both teeth revealed Fig. B.-Section of upper right canine showing quite advanced resorption and bone formation within the resorbed area. The section does not paas through the root canal but shows deposited on its walls. (Hematoxylin and eosin stain. some of the calcifled “osteodentine” Magnification. x8 ; reduced ]k.) Fig. 9.-Section of upper left canine showing extensive resorption and bony replacement of tooth substance. (Hematoxylin and eosin stain. Magnification. x8 ; reduced % 1 Fig. lO.-Osteoclastlc resorption of dentine is evident. In places, “osteodentine” haa been laid down on previously resorbed areas of dentine. Woven bone is present within a flbroblastic tissue which is lightly infiltrated with round cells. (Hematoxylin and eosin stain. Magnification. x105 ; reduced $4.)
Volume 17 Number 3
SURGTCAL
Fig.
POSITIONING
OF MAXILLARY
Fig.
8.
Fig. Figs.
8 to lo.-(For
293
CANINES
9.
10.
legends, see opposite
gage.)
that the pulp cavity, although almost completely obliterated 11y ‘ i osteodent ino ’ ’ laitl do\Vn on the walls, contained a fibrous tissue which communic*atted with t.hc periapic-a1 t.issuc through the apical foramen and with the fibrous tissue in tht! area of rc++orption. A vrry mild iniiltra~t! of round cells was scattcrrd diffusely throughout the fibrous tissue, but no plasma. ~11s ww sceu. Coraclzlsion: External root resorption and ankylosis of the maxillary canines.
COMMENT
It is noteworthy that, even though the apical vessels supplying the right maxillary canine were, without doubt, ruptured at the time of the operation, pulpal degeneration rather than pulpal necrosis resulted. It would seem that a similar pulpal reaction had developed in both teeth, and the changes conform with the findings of Agnew and FongE in experimental transplantation in the rhesus monkey. It is considered that temporary deprivation of nuarition to the more specialized cells results in a degenerative change. In some inst.ances partial regeneration of odontoblasts may occur, but generally the fibroblast is the cell which survives and extensive calcification is often observed in a fibrillar type of scar tissue lining the surrounding dentinal wall. Holland,2 who mentions t.hat he has used the “technique of surgical orthodontics” on more than 300 teeth, published det.ailed records of eight cases,’ the longest postoperative follow-up in any one case being only 10 months. He observed calcification in the pulp canals bu6 resorption in one case only, and this on the dist.al aspect of an upper left canine 7 months after surgical intervention. However, external root resorption of varying degree is a fairly constant finding among transplant.ed and replanted teeth and, to quote Thorna,* “the ultimate fate of replant.ed teeth is resorption of the tooth with replacement of the dental tissue by bone.” The teet,h are not retained permanently, their “life” being dependent on the rate and extent of the resorptive process. The cause of the resorption is not known. External root resorption is often associated with new bone formation resulting in ankylosis. The ankylosis may be a true ankylosis from union of bone and tooth substance, or it may bc due to a dovetailing of bone laid down in areas of resorpDion. Whatever the type of ankylosis, further eruption of a tooah is highly unlikely: t.he positioning of a toot.h so that it is short of the occlusal plane may therefore result in its failure to erupt completely. SUMMARY
A case in which the technique of surgical positioning was carried out, OII maxillary canines in a 12-year-old girl has been reported. Nine months postoperatively each tooth showed advanced resorption of its roots and was cxtracted. Histologically, each tooth showed ankylosis. tElc
REFERENCES 1. Symposium:
Transplantation,
Replantation
and Surgical
ORAL MED. & ORAL PATH. 9: 3-140, 1956.
Positioning
of Teeth, ORAL SURG.,
2. Holland, D. J.: The Surgical Positioning of Unerupted Impacted Teeth tics), ORAL Smw., OIUL MED. & ORAL PATH. 9: 130, 1956.
(Surgical
Orthodon-
Volume17 Number3
SURGICAL
POSITIONING
OF MAXTLLARY
CANINES
295
3. Villaseca. H. Rodolfo: Autoaenous Transulantation of an Imuacted Cuwid to the First Bikpid Alveolus for Orthodontic Purposes : Case Repor%,,D. Abat: 3: 144, 1953. 4. Thoma. K. H.: Sureieal Positionine: of Erupted Teeth in Torso-Occlusion, OILAL SURG..ORAL LED. & ORAL~PATH.9: 125, i956. * 5. Baden, Ernest: Surgical Management of Unerupted Canines and Premolars, ORAL SURQ., ORAL MED. & ORAL PATH. 9: 141, 1956. 6. Agnew, R. G., and Fong, C. C.: Histologic Studies in Experimental Transplantation of Teeth, ORAL Sm.&, ORAL MED. $ OrmA PATH. 9: 18, 1956. 7. Holland, D. J.: A Teachnique of Surgical Orthodontics, Am. J. Orthodontics 41: 27, 1955. 8. Thoma, K. H.: Oral Surgery, ed. 3, St. Louis, 1958, The C. V. Mosby Company, p. 420.