Clinical and roentgenographic evaluation of thirty-seven autotransplantedimpacted maxillary canines Badri Azaz, D.M.D., * Yerucham Zilbermun, D.M.D., ** and Tikva Hackak, D.M.D., Jerusalem, Israel THE HEBREW UNIVERSITY-HADASSAH FOUNDED
SCHOOL OF DENTAL
MEDICINE,
BY THE ALPHA OMEGA FRATERNITY
Thirty-seven autotransplanted canines in thirty-one patients were observed for a period of 2 to 7 years, Transplants with Iess than 2 years’ follow-up were not included in this study. Although the surgical, root canal, and fixation techniques were identical, the delayed pathophysiologic changes were different.
Tis second he maxillary canine is one of the most frequently misplacedteeth in the dental arch and only to the third molars in frequency of impacti0n.l Many attemptshave been madeto bring this impacted tooth into a correct position in the dental arch, becauseof its esthetic importance and also becauseit has such structural strength that it plays a major role in oral rehabilitation.2 If the impacted canine is in a favorable position and hasenough space in the arch, it is possible to expose the impacted canine surgically and direct it orthodontically into its normal position with traction.3 However, both in caseswith severe displacement, in which surgical exposure and orthodontic traction are unlikely to be successful, and in patients who are past their youth and object to orthodontic treatment, autotransplantation could be considered the treatment of choice. This procedure has become more acceptable4-6with or without root canal filling, dependingon the stageof root formation.’ It is essential that there be adequatespaceprior to the surgical intervention. The purpose of this study was to determine, in a certain number of cases,the fate of the autotransplantedimpacted maxillary canines under standardizedconditions of operation, root canal filling, and fixation. This article is part of the thesis submitted by Miss T. Hackak in partial fulfillment of the requirements for the D.M.D. degree. *Department of Oral Surgery. **Department of Orthodontics.
8
Vohmle 45 Number I
Autotransplanted
Table I. Distribution
No.
43
(years)
Upto 18 18to25 Over 25 Total
of
No.
subjects
5 II 5 21
maxillary
canines
9
of the autotransplanted canines according to side, age, and sex Females
group
impacted
Males
Transplants
of teeth 8 13 _f 27
Unilateral 2 9 4 15
No.
-No.of Bilateral subjects 3 2 1 6
2 5 3 10
Transplants
h’o
Bilateral
No. of subjects
-
7 I6 8 31
of teeth 2 5 3 10
__-.
Total
Unilateral 2 5 3 IO
4 teeth 10 IX 9 ii? -_-
MATERIALS AND METHODS
Thirty-seven fully formed, impacted, maxillary canines in thirty-one patients were autotransplanted by the staff of the Oral Surgery Department within the last 7 years after grafting. Transplants of less than 2 years’ follow-up were not included in the study. Table I presents the distribution of the evaluated group in relation to their sex and age. Transplantation was performed in twenty-one female and ten male patients. The bilateral impacted canines were found only in females. The ages of the patients ranged from 13 to 36 years. The teeth were assessed in follow-up sessions, both clinically with respect to their stability, color, pocket depth, and tenderness to percussion, and radiographically, with the bone regeneration and root condition being examined. AUTOTRANSPLANTATION
TECHNIQUE
The cases for autotransplantation were selected carefully, with attention being paid to the space available in the arch. If this was not present naturally, then it was created orthodontically prior to the operation. As most of the canines were impacted palatally, local anesthesia was induced and a palatal mucoperiosteal flap was reflected. The bone overlying the canine was carefully removed, with care being taken not to injure any part of the root. When sufficient bone was removed, the canine was gently elevated from its socket and wrapped in a wet saline swab. A new socket was then prepared in order that the tooth could be placed in its correct anatomic position. A standardized root canal filling was done with zinc oxide-eugenol paste and gutta-percha points. Apicoectomy was performed only if the apex caused difficulty in fitting the root into the newly created socket. In all cases, the time between removal of the impacted tooth and its placement in the new socket was not more than 25 minutes. Postoperative fixation with either a surgical or an orthodontic arch was maintained for a period of about 10 weeks. POSTOPERATIVE CARE
The patient was given prophylactic antibiotic cover for 5 days and encouraged to practice oral hygiene. A postoperative radiograph was taken immediately after the operation or a week later to provide a base line for further follow-up. After removal of the splint, the teeth were scaled and polished and occlusal adjustment was performed. The transplants were grouped for clinical evaluation as follows:
10
Azaz, Zilberman, and Hackak
Oral Surg. January, 1978
Fig. 1. A, Preoperative roentgenogram. B, Fixation of the autotransplanted canine by Erich arch. C and D, Roentgenographic and clinical photographs showing successful appearance after 4 years 9 months.
1. Successful-Completely asymptomatic, with tooth stability and color normal, pocket depth up to 2 mm, and no sign of tendernessto percussion. 2. Good-Tooth functional but with somemild changes,such asfirst-degreemobility, alteration in color, pocket depth up to 4 mm., and mild tendernessto percussion. 3. Failure-Tooth requiring extraction. The radiographic criteria were as follows: 1. Successful A. Normal appearance(Fig. 1). B. Surface resorption with spontaneoushealing (Fig. 2). C. No regeneration of bone at the gingival level (Fig. 3). 2. Good-Progression of mnlacement level (Fig. 4). 3. Failure
A. Inflammatory resorption (Fig. 5). B. Tooth loss.
Volume 45 Number I
Autotransplanted impacted maxillary canines
11
Fig. 2. A, Preoperative roentgenogram. B, Seventeen months after autotransplantation with signs of resorption in the apical third of the root. C, No further resorption 4 years 7 months since the resorption was first noticed. D, Normal clinical appearance 6 years after transplantation.
RESULTS The general success of the transplantations, as assessed in Table II, is indicated by the fact that only four out of the total of thirty-seven teeth were clinical failures. The progression of replacement resorption seems to be the main radiographic finding. Groups 1 and 2, which were considered as roentgenographic successes, included thirtyfive out of forty-five teeth. The long-term assessment is better evaluated by x-ray examination than by clinical judgment. In a few cases, while the clinical appearance was favorable, radiogmphically the prognosis was found to be poor.
12 Azaz, Zilberman, and Hackak
Fig. 3. A and B, Preoperative appearance. C, Immediately postoperative. D, Two months after transplantation. E, Four years after transplantation, showing lack of regeneration of bone at the gingival level. F, Clinical appearance 4 years after autotransplantation.
DISCUSSION
Dachi and Howell,, in a routine examination of full-mouth radiographs of more than 3,800 patients, found that 0.92 per cent had impacted maxillary canines. Females showed a higher percentage of impaction (1.17 per cent compared to 0.5 1 per cent of males), a finding that is supported by others, 9 and by the present study. Dachi and Howell, found only two cases of bilateral impaction, a finding that is low compared to the 14 per cent reported by Rhorer, and approximately one third of all maxillary impactions in Nordenram and Stromberg’s, impactions group. In our small group almost 20 per cent were bilateral. When an impacted canine is disclosed, especially if it is in a poor position for orthodontic traction or in an older patient who objects to orthodontic treatment, one must consider alternative treatment approaches, such as: 1. Leaving the deciduous canine in place if still present. This is a poor alternative, as
Volume 45 Number I
Autotransplanted impacted maxillary canines
13
Fig. 4. A, Preoperative roentgenogram. B, After regaining of space. C, Six months atIer transplantation, showing early surface resorption. D, Eleven months after transplantation, showing obvious inflammatory resorption. E, Progression of bone replacement. F, Normal clinical appearance in spite of progression of bone replacement.
the deciduous canine is usually involved to a certain degree with caries and with moderate to severe resorption of its root, or these problems may develop eventually. 2. Restoration of the space of the missing deciduous canine with a bridge or a removable prosthesis. The tooth preparation for this bridge in young persons may damage the vitality of the abutment teeth. On the other hand, a partial denture may no1 be advisable as the caries activity may still be high. In both of the alternatives mentioned it is believed that the permanent canine should not be left impacted as the tooth may develop a follicular cyst or cause resorption of the roots of adjacent teeth due to local factors. Thus, if surgery is planned, consideration should be given to autotransplantation of the impacted maxillary canine as the treatment of choice, especially in youngsters. The cases for autotransplantation should be selected carefully. A suitable space in the arch is a prerequisite. In three cases with follow-up of less than 2 years (not included in the reported group), the space in the arch did not allow insertion of the impacted canine in the preformed new socket and some grinding of root had to be carried out. Each of these
14 Azaz, Zilberman, and Hackak
Oral Surg. January, 1978
Fig. 5. A, Preoperative roentgenogram. B, Two years after transplantation. C, Progression of inflammatory resorption 5 years after transplantation. D, Clinical appearance after 5 years.
subsequently showed very rapid resorption and had to be extracted within a year of the surgical procedure. This phenomenonis well known in casesin which the cementum is harmed during autotransplantation procedures.2,lo, r1 Our experience also shows that the prognosis of autotransplantationin young patients is more promising. Even though the patients were seenfrequently, it was difficult to assess the point at which resorption began. Another observation reported also by Andreasenand Hj@ting-Hansen12was that in somecasesthe inflammatory resorption subsidedin favor of bone repair which, of course, improves the tooth’s prognosis. However, the resorption in our group was higher than that reported by Moss,lOwho reported that thirty-one teeth out of fifty did not show any signs of resorption at least 3 years after the transplantation. There is a noticeable dearth of information in the literature on the behaviour of autotransplanted canines which had previously undergone surgical exposure, with or
Volume 45 Number 1
Autotransplanted impacted maxillary canines
15
II. Distribution of autotransplantedteeth according to clinical evaluation criteria and follow-up periods -.
Table
Observation periods Clinical group Successful
No. of teeth
2-5 yr.
Over 5 JJ~
Good
23 10
14 8
9 2
Failure Total
4 37
3 25
_1 12
III. Distribution of autotransplantedteeth according to roentgenographic changesand follow-up periods
Table
Observation periods
X-ray groups Successful A. Normal appearance (Fig. 1) 9. Surface resorption with spontaneous healing (Fig. 2) C. No regeneration of bone at the gingival level (Fig. 3) Good Progression of replacement resorption (Fig. 4) Failure A. Inflammatory resorption (Fig. 5) B. Tooth loss Total
No. of teeth
2 -5 yr.
Over 5 yr.
6 9 8 12 9 2 45*
3 6 6 I0 6
3 3 :! 2 3 I 14*
31*
*These totals are greater than their respective base lines as several teeth were included in more than one category.
without orthodontic traction, and which had failed. In our reported group, seven such teeth had been uncovered, of which four had also undergone orthodontic traction. The results of their autotransplantation showed no ciinical or radiographic differences when comparedto the others in the group. The purpose of this study was to evaluate the prognosis of autotransplantedimpacted caninesby comparing clinically standardizedgroups. It is our belief that the critical period is the first 2 years following intervention, in which the pathologic changeswill be already seen. In all of the autotransplantedteeth root canals were filled by the sametechnique. The surgical intervention was identical, and the splinting was for the sameperiod of time. Yet the delayed pathophysiologic changeswere different. From this, one must conclude that, except for the managementof theseteeth, there are still individual unknown factors which render the prognosis of autotransplanted impacted maxillary canines questionable, at least. REFERENCES
1. Thoma, K. H.: Oral Surgery, ed. 3, St. Louis, 19.58, The C. V. Mosby Company, pp. 378-390. 2. Thom-rer, K. E.: Autogenous Transplantation of Unerupted Maxillary Canines: A Clinical and Histological Investigation Over Five Years, Dent. Practit. 21: 251-257, 1971.
16 Azaz, Zilberman, and Hackak
Oral Surg. January, 1978
3. Hovinga, J.: Auto-transplantation of Maxillary Canines: A Long Term Evaluation, I. Oral Surg. 27: 701-708, 1969. 4. Emmersten, E., and Andreasen, J. 0.: Replantation of Extracted Molars: A Radiographic and Histologic Study, Acta Odontol. Stand. 24: 327-346, 1966. 5. Miller, H. M.: Reimplanting Human Teeth, Dent. Survey 29: 1439-1443, 1953. 6. Simson, W.: The Reimplanted Maxillary Canine, Br. J. Oral Surg. 4: 150-154, 1966. 7. Dachi, S. F., and Howell, F. V.: Surveys of 3,874 Routine Full-Mouth Radiographs. II. A Study of Implanted Teeth, ORAL SURG. 14: 1165-l 169, 1961. 8. Nordenram, A., and Stronberg, C.: Positional Variations of the Impacted Upper Canine: A Clinical and Radiologic Study, ORAL SURG. 22: 71 l-714, 1966. 9. Rohrer, A.: Displaced and Impacted Canines: A Radiographic Research, Int. J. Orthod. 15: 1003-1020, 1929. IO. Moss, J. P.: An Orthodontic Approach to Surgical Problems, Am. J. Orthod. 68: 363-390, 1975. II. Heslop, I. H.: Autogenous Replantation of the Maxillary Canine, Br. J. Oral Surg. 5: 135-140, 1967. 12. Andreasen, J. O., and Hjorting-Hansen, E.: Replantation of Teeth. II. Histological Study of 22 Replanted Anterior Teeth in Humans, Acta Odontol. Stand. 24: 287-306, 1966. Reprint requests to:
Dr. Badri Azaz Department of Oral Surgery Hebrew University-Hadassah School of Dental Medicine P. 0. Box 499 Jerusalem, Israel
SCHOOL OF DENTAL
MEDICINE,
BY THE ALPHA OMEGA FRATERNITY
Thirty-seven autotransplanted canines in thirty-one patients were observed for a period of 2 to 7 years, Transplants with Iess than 2 years’ follow-up were not included in this study. Although the surgical, root canal, and fixation techniques were identical, the delayed pathophysiologic changes were different.
Tis second he maxillary canine is one of the most frequently misplacedteeth in the dental arch and only to the third molars in frequency of impacti0n.l Many attemptshave been madeto bring this impacted tooth into a correct position in the dental arch, becauseof its esthetic importance and also becauseit has such structural strength that it plays a major role in oral rehabilitation.2 If the impacted canine is in a favorable position and hasenough space in the arch, it is possible to expose the impacted canine surgically and direct it orthodontically into its normal position with traction.3 However, both in caseswith severe displacement, in which surgical exposure and orthodontic traction are unlikely to be successful, and in patients who are past their youth and object to orthodontic treatment, autotransplantation could be considered the treatment of choice. This procedure has become more acceptable4-6with or without root canal filling, dependingon the stageof root formation.’ It is essential that there be adequatespaceprior to the surgical intervention. The purpose of this study was to determine, in a certain number of cases,the fate of the autotransplantedimpacted maxillary canines under standardizedconditions of operation, root canal filling, and fixation. This article is part of the thesis submitted by Miss T. Hackak in partial fulfillment of the requirements for the D.M.D. degree. *Department of Oral Surgery. **Department of Orthodontics.
8
Vohmle 45 Number I
Autotransplanted
Table I. Distribution
No.
43
(years)
Upto 18 18to25 Over 25 Total
of
No.
subjects
5 II 5 21
maxillary
canines
9
of the autotransplanted canines according to side, age, and sex Females
group
impacted
Males
Transplants
of teeth 8 13 _f 27
Unilateral 2 9 4 15
No.
-No.of Bilateral subjects 3 2 1 6
2 5 3 10
Transplants
h’o
Bilateral
No. of subjects
-
7 I6 8 31
of teeth 2 5 3 10
__-.
Total
Unilateral 2 5 3 IO
4 teeth 10 IX 9 ii? -_-
MATERIALS AND METHODS
Thirty-seven fully formed, impacted, maxillary canines in thirty-one patients were autotransplanted by the staff of the Oral Surgery Department within the last 7 years after grafting. Transplants of less than 2 years’ follow-up were not included in the study. Table I presents the distribution of the evaluated group in relation to their sex and age. Transplantation was performed in twenty-one female and ten male patients. The bilateral impacted canines were found only in females. The ages of the patients ranged from 13 to 36 years. The teeth were assessed in follow-up sessions, both clinically with respect to their stability, color, pocket depth, and tenderness to percussion, and radiographically, with the bone regeneration and root condition being examined. AUTOTRANSPLANTATION
TECHNIQUE
The cases for autotransplantation were selected carefully, with attention being paid to the space available in the arch. If this was not present naturally, then it was created orthodontically prior to the operation. As most of the canines were impacted palatally, local anesthesia was induced and a palatal mucoperiosteal flap was reflected. The bone overlying the canine was carefully removed, with care being taken not to injure any part of the root. When sufficient bone was removed, the canine was gently elevated from its socket and wrapped in a wet saline swab. A new socket was then prepared in order that the tooth could be placed in its correct anatomic position. A standardized root canal filling was done with zinc oxide-eugenol paste and gutta-percha points. Apicoectomy was performed only if the apex caused difficulty in fitting the root into the newly created socket. In all cases, the time between removal of the impacted tooth and its placement in the new socket was not more than 25 minutes. Postoperative fixation with either a surgical or an orthodontic arch was maintained for a period of about 10 weeks. POSTOPERATIVE CARE
The patient was given prophylactic antibiotic cover for 5 days and encouraged to practice oral hygiene. A postoperative radiograph was taken immediately after the operation or a week later to provide a base line for further follow-up. After removal of the splint, the teeth were scaled and polished and occlusal adjustment was performed. The transplants were grouped for clinical evaluation as follows:
10
Azaz, Zilberman, and Hackak
Oral Surg. January, 1978
Fig. 1. A, Preoperative roentgenogram. B, Fixation of the autotransplanted canine by Erich arch. C and D, Roentgenographic and clinical photographs showing successful appearance after 4 years 9 months.
1. Successful-Completely asymptomatic, with tooth stability and color normal, pocket depth up to 2 mm, and no sign of tendernessto percussion. 2. Good-Tooth functional but with somemild changes,such asfirst-degreemobility, alteration in color, pocket depth up to 4 mm., and mild tendernessto percussion. 3. Failure-Tooth requiring extraction. The radiographic criteria were as follows: 1. Successful A. Normal appearance(Fig. 1). B. Surface resorption with spontaneoushealing (Fig. 2). C. No regeneration of bone at the gingival level (Fig. 3). 2. Good-Progression of mnlacement level (Fig. 4). 3. Failure
A. Inflammatory resorption (Fig. 5). B. Tooth loss.
Volume 45 Number I
Autotransplanted impacted maxillary canines
11
Fig. 2. A, Preoperative roentgenogram. B, Seventeen months after autotransplantation with signs of resorption in the apical third of the root. C, No further resorption 4 years 7 months since the resorption was first noticed. D, Normal clinical appearance 6 years after transplantation.
RESULTS The general success of the transplantations, as assessed in Table II, is indicated by the fact that only four out of the total of thirty-seven teeth were clinical failures. The progression of replacement resorption seems to be the main radiographic finding. Groups 1 and 2, which were considered as roentgenographic successes, included thirtyfive out of forty-five teeth. The long-term assessment is better evaluated by x-ray examination than by clinical judgment. In a few cases, while the clinical appearance was favorable, radiogmphically the prognosis was found to be poor.
12 Azaz, Zilberman, and Hackak
Fig. 3. A and B, Preoperative appearance. C, Immediately postoperative. D, Two months after transplantation. E, Four years after transplantation, showing lack of regeneration of bone at the gingival level. F, Clinical appearance 4 years after autotransplantation.
DISCUSSION
Dachi and Howell,, in a routine examination of full-mouth radiographs of more than 3,800 patients, found that 0.92 per cent had impacted maxillary canines. Females showed a higher percentage of impaction (1.17 per cent compared to 0.5 1 per cent of males), a finding that is supported by others, 9 and by the present study. Dachi and Howell, found only two cases of bilateral impaction, a finding that is low compared to the 14 per cent reported by Rhorer, and approximately one third of all maxillary impactions in Nordenram and Stromberg’s, impactions group. In our small group almost 20 per cent were bilateral. When an impacted canine is disclosed, especially if it is in a poor position for orthodontic traction or in an older patient who objects to orthodontic treatment, one must consider alternative treatment approaches, such as: 1. Leaving the deciduous canine in place if still present. This is a poor alternative, as
Volume 45 Number I
Autotransplanted impacted maxillary canines
13
Fig. 4. A, Preoperative roentgenogram. B, After regaining of space. C, Six months atIer transplantation, showing early surface resorption. D, Eleven months after transplantation, showing obvious inflammatory resorption. E, Progression of bone replacement. F, Normal clinical appearance in spite of progression of bone replacement.
the deciduous canine is usually involved to a certain degree with caries and with moderate to severe resorption of its root, or these problems may develop eventually. 2. Restoration of the space of the missing deciduous canine with a bridge or a removable prosthesis. The tooth preparation for this bridge in young persons may damage the vitality of the abutment teeth. On the other hand, a partial denture may no1 be advisable as the caries activity may still be high. In both of the alternatives mentioned it is believed that the permanent canine should not be left impacted as the tooth may develop a follicular cyst or cause resorption of the roots of adjacent teeth due to local factors. Thus, if surgery is planned, consideration should be given to autotransplantation of the impacted maxillary canine as the treatment of choice, especially in youngsters. The cases for autotransplantation should be selected carefully. A suitable space in the arch is a prerequisite. In three cases with follow-up of less than 2 years (not included in the reported group), the space in the arch did not allow insertion of the impacted canine in the preformed new socket and some grinding of root had to be carried out. Each of these
14 Azaz, Zilberman, and Hackak
Oral Surg. January, 1978
Fig. 5. A, Preoperative roentgenogram. B, Two years after transplantation. C, Progression of inflammatory resorption 5 years after transplantation. D, Clinical appearance after 5 years.
subsequently showed very rapid resorption and had to be extracted within a year of the surgical procedure. This phenomenonis well known in casesin which the cementum is harmed during autotransplantation procedures.2,lo, r1 Our experience also shows that the prognosis of autotransplantationin young patients is more promising. Even though the patients were seenfrequently, it was difficult to assess the point at which resorption began. Another observation reported also by Andreasenand Hj@ting-Hansen12was that in somecasesthe inflammatory resorption subsidedin favor of bone repair which, of course, improves the tooth’s prognosis. However, the resorption in our group was higher than that reported by Moss,lOwho reported that thirty-one teeth out of fifty did not show any signs of resorption at least 3 years after the transplantation. There is a noticeable dearth of information in the literature on the behaviour of autotransplanted canines which had previously undergone surgical exposure, with or
Volume 45 Number 1
Autotransplanted impacted maxillary canines
15
II. Distribution of autotransplantedteeth according to clinical evaluation criteria and follow-up periods -.
Table
Observation periods Clinical group Successful
No. of teeth
2-5 yr.
Over 5 JJ~
Good
23 10
14 8
9 2
Failure Total
4 37
3 25
_1 12
III. Distribution of autotransplantedteeth according to roentgenographic changesand follow-up periods
Table
Observation periods
X-ray groups Successful A. Normal appearance (Fig. 1) 9. Surface resorption with spontaneous healing (Fig. 2) C. No regeneration of bone at the gingival level (Fig. 3) Good Progression of replacement resorption (Fig. 4) Failure A. Inflammatory resorption (Fig. 5) B. Tooth loss Total
No. of teeth
2 -5 yr.
Over 5 yr.
6 9 8 12 9 2 45*
3 6 6 I0 6
3 3 :! 2 3 I 14*
31*
*These totals are greater than their respective base lines as several teeth were included in more than one category.
without orthodontic traction, and which had failed. In our reported group, seven such teeth had been uncovered, of which four had also undergone orthodontic traction. The results of their autotransplantation showed no ciinical or radiographic differences when comparedto the others in the group. The purpose of this study was to evaluate the prognosis of autotransplantedimpacted caninesby comparing clinically standardizedgroups. It is our belief that the critical period is the first 2 years following intervention, in which the pathologic changeswill be already seen. In all of the autotransplantedteeth root canals were filled by the sametechnique. The surgical intervention was identical, and the splinting was for the sameperiod of time. Yet the delayed pathophysiologic changeswere different. From this, one must conclude that, except for the managementof theseteeth, there are still individual unknown factors which render the prognosis of autotransplanted impacted maxillary canines questionable, at least. REFERENCES
1. Thoma, K. H.: Oral Surgery, ed. 3, St. Louis, 19.58, The C. V. Mosby Company, pp. 378-390. 2. Thom-rer, K. E.: Autogenous Transplantation of Unerupted Maxillary Canines: A Clinical and Histological Investigation Over Five Years, Dent. Practit. 21: 251-257, 1971.
16 Azaz, Zilberman, and Hackak
Oral Surg. January, 1978
3. Hovinga, J.: Auto-transplantation of Maxillary Canines: A Long Term Evaluation, I. Oral Surg. 27: 701-708, 1969. 4. Emmersten, E., and Andreasen, J. 0.: Replantation of Extracted Molars: A Radiographic and Histologic Study, Acta Odontol. Stand. 24: 327-346, 1966. 5. Miller, H. M.: Reimplanting Human Teeth, Dent. Survey 29: 1439-1443, 1953. 6. Simson, W.: The Reimplanted Maxillary Canine, Br. J. Oral Surg. 4: 150-154, 1966. 7. Dachi, S. F., and Howell, F. V.: Surveys of 3,874 Routine Full-Mouth Radiographs. II. A Study of Implanted Teeth, ORAL SURG. 14: 1165-l 169, 1961. 8. Nordenram, A., and Stronberg, C.: Positional Variations of the Impacted Upper Canine: A Clinical and Radiologic Study, ORAL SURG. 22: 71 l-714, 1966. 9. Rohrer, A.: Displaced and Impacted Canines: A Radiographic Research, Int. J. Orthod. 15: 1003-1020, 1929. IO. Moss, J. P.: An Orthodontic Approach to Surgical Problems, Am. J. Orthod. 68: 363-390, 1975. II. Heslop, I. H.: Autogenous Replantation of the Maxillary Canine, Br. J. Oral Surg. 5: 135-140, 1967. 12. Andreasen, J. O., and Hjorting-Hansen, E.: Replantation of Teeth. II. Histological Study of 22 Replanted Anterior Teeth in Humans, Acta Odontol. Stand. 24: 287-306, 1966. Reprint requests to:
Dr. Badri Azaz Department of Oral Surgery Hebrew University-Hadassah School of Dental Medicine P. 0. Box 499 Jerusalem, Israel
