autotransplantation of premolars in a patient with …treatment of a patient in the early mixed...

Autotransplantation of teeth can significantly reduce

treatment time in cases of aplasia, tooth loss, or ectopia, provided a suitable tooth is available and the anatomical conditions are favor-able. As a viable option for restor-ing edentulous areas in young patients whose alveolar growth is not yet complete, it can resolve complicated treatment problems in the dental arches. Moreover, this approach allows replacement of a missing tooth with a natural

tooth rather than a prosthesis or osseointegrated implant.

Autotransplantation of pre-molars with partly formed roots is a predictable modality,1-9 be -cause transplanted teeth have the capacity for preservation of the alveolar ridge10 and functional adaptation.11,12

This article describes the treatment of a patient in the early mixed dentition using a combina-tion of autotransplantation and orthodontics.

Diagnosis and Treatment Plan

A 10-year-old female pre-sented with congenitally missing mandibular permanent central incisors and second premolars (Fig. 1). She was still in the early mixed dentition, indicating delayed development for her age. Clinical examination showed a convex profile, normal vertical facial proportions, and good facial symmetry, with a Class I molar

VOLUME XLV NUMBER 7 399

CASE REPORTAutotransplantation of Premolars in a Patient with Multiple Congenitally Missing Teeth

KIYOSHI TAI, DDS JAE HYUN PARK, DMD, MSD, MS, PHDDAISUKE HAYASHI, DDSASUKA MIURA, DDS

© 2011 JCO, Inc.

Dr. MiuraDr. HayashiDr. ParkDr. Tai

Dr. Tai is a doctoral student, Okayama Department of Oral and Maxillofacial Reconstructive Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan. Drs. Tai, Hayashi, and Miura are in the private practice of orthodontics in Okayama. Dr. Tai is also a Visiting Adjunct Assistant Professor, and Dr. Park is Associate Professor and Chair, Postgraduate Orthodontic Program, Arizona School of Dentistry & Oral Health, A.T. Still University, 5855 E. Still Circle, Mesa, AZ 85206. Dr. Park is also an International Scholar, Graduate School of Dentistry, Kyung Hee University, Seoul, South Korea. E-mail Dr. Park at [email protected].

©2011 JCO, Inc. May not be distributed without permission. www.jco-online.com

400 JCO/JULY 2011

Fig. 1 10-year-old female patient with Class I occlusion and congeni-tally missing mandibular central incisors and second premolars before treatment.

Autotransplantation of Premolars in a Patient with Multiple Missing Teeth

relationship, a 2mm overjet, and a 1mm overbite. The etiology of the missing teeth was presumed to be genetic, since there was no history of trauma or infection to the mouth, teeth, or jaws.

Panoramic radiographs con-firmed the agenesis of the man-dibular permanent central inci-sors and second premolars and showed no evidence of third molars. Cephalo metric analysis indicated a Class I skeletal pat-tern with a normal growth pattern and proclination of both the max-illary and mandibular incisors (Table 1).

The treatment plan called for transplanting the maxillary right first premolar to the man-dibular right second premolar region and transplanting the max-illary left second premolar to the mandibular left second premolar region. While we waited for the patient to progress further into the

permanent dentition, we took a panoramic film with a metal ball in place to indicate the amount of magnification, and we calculated the appropriate sizes of the recip-ient sites (adjusted for magnifica-tion). The patient was seen every three months to monitor tooth eruption and root development.

Treatment Progress

Autotransplantation was performed when the patient was 12 years old. Her deciduous man-dibular second molars were removed under local anesthesia, with care taken to preserve the buccal and lingual alveolar bone during extraction, and the sockets were prepared to receive the transplanted maxillary premolars. The intra-alveolar septum was trimmed with a chisel, and the sockets were irrigated. The donor teeth—the maxillary right first

premolar and maxillary left sec-ond premolar—were carefully removed, keeping their roots and remaining periodontal ligaments (PDLs) intact to avoid separation of Hertwig’s epithelial root sheath (Fig. 2). Root development of the donor teeth was about 75%.

As quickly as possible, each transplanted tooth germ was placed in its prepared socket with its occlusal surface slightly below the occlusal plane, thus avoiding premature contacts. The flaps were sutured with black silk, and the transplanted teeth were fixed in place by crossing the same suture material over the occlusal surfaces.

Chlorhexidine rinse and amoxicillin were prescribed for one week. The patient was in -structed not to chew any foods during the first month of the post-operative period, after which she was permitted to chew a soft diet


Tai, Park, Hayashi, and Miura

TABLE 1CEPHALOMETRIC DATA

Japanese Norm Pretreatment Post-Treatment One-Year Follow-Up

SNA 82.0° 84.0° 86.3° 86.5°SNB 80.0° 82.6° 85.9° 86.3°ANB 2.0° 1.4° 0.4° 0.7°Wits 1.1mm –4.5mm –6.7mm –6.3mmSN-MP 32.0° 30.3° 27.4° 27.6°FH-MP 25.0° 27.8° 25.7° 25.5°LFH (ANS-Me/N-Me) 55.0% 57.1% 60.0% 59.7%U1-SN 104.0° 115.2° 105.9° 106.4°U1-NA 22.0° 31.1° 19.6° 20.1°IMPA 90.0° 95.0° 89.3° 89.9°L1-NB 25.0° 28.0° 22.5° 22.9°U1/L1 124.0° 119.5° 137.4° 136.9°Upper lip 1.2mm –0.3mm –2.5mm –2.7mmLower lip 2.0mm –0.1mm –1.8mm –1.9mm

for one month, gradually increas-ing the chewing load to normal function within three months.

A day after surgery, the transplanted teeth had retained their positions; thereafter, the sta-bility and position of the teeth were assessed weekly. Sutures were removed one week after transplantation, and flexible sta-bilization wires were bonded to connect the transplanted teeth to the adjacent teeth. Full clinical and radiographic examinations were performed one, four, and 12 weeks and six months after sur-gery to evaluate periodontal heal-ing, root growth, tooth eruption,

and pulpal healing and to check for any signs of pulp canal oblit-eration (PCO).

Six months after autotrans-plantation, full .018" edgewise appliances* were bonded in both arches. No PCO was observed on the pretreatment radiographs4-6

(Figure 3 shows records taken after two to three months of ortho dontic treatment).

Fixed appliances were removed following 36 months of active treatment. A 4-4 .0175" twisted lingual wire was bonded in the mandibular arch, and an Essix** retainer was delivered for the maxillary arch.

Treatment Results

Post-treatment records showed proper midline alignment and an acceptable overbite and overjet (Fig. 4A). The panoramic radiograph indicated proper root parallelism, with no signs of bone or root resorption. Cephalometric superimpositions revealed no sig-nificant skeletal changes and con-firmed the normal inclination of the anterior teeth (Fig. 4B, Table 1).

402 JCO/JULY 2011


Fig. 2 Transplantation of donor teeth at age 12. A. Site preparation and transplantation of extracted maxillary right first premolar to mandibular right second premolar site. B. Site preparation and transplantation of extracted maxillary left second premolar to mandibular left second premolar site.

*3M Unitek, 2724 S. Peck Road, Monrovia, CA 91016; www.3mUnitek.com.

**Trademark of Dentsply Raintree Essix, 6448 Parkland Drive, Sarasota, FL 34243; www.essix.com.

A

B

Post-treatment radiographic examination of the transplanted teeth showed complete root growth with intact laminae durae and well-defined periodontal spaces. Both transplanted teeth, particularly the left second pre-molar, displayed partial PCO at this point. Alveolar ridge levels were similar to those of the adja-cent teeth, and the final crown-to-root ratios were greater than 1:1. The response of the transplanted teeth to electric pulp testing was positive, their mobility was nor-mal, and the sulcus depths were less than 3mm.

After one year of retention, the patient’s occlusion had re -mained fairly stable (Fig. 5).

Discussion

Autotransplantation, which has become an accepted modality in orthodontics,13 offers several benefits compared with alterna-

tives such as dental implants. A successfully transplanted tooth recovers its normal periodontal health and proprioceptive func-tion after a single surgical pro-cedure. Transplantation allows natural biological response, including continued alveolar bone induction,14 and lets the patient feel a normal chewing sensation.

Although studies have re -ported survival rates as high as 90% for transplanted teeth,5 un -desirable complications such as root resorption or dentoalveolar ankylosis can occur. If there is a residual Hertwig’s epithelial root sheath on the developing tooth, the capillaries and PDLs can pro-liferate through the apex, filling the pulp canal with vital tissues within a few months after auto-transplantation.4-6 Calcification of the root canal may then result in a complete or partial oblitera-tion—a common problem associ-ated with autotransplantation.

While PCO can result in discol-oration of the tooth, however, it does not affect the success of the procedure in vital pulp.4

For successful autotrans-plantation, the following proto-cols should be observed:

1. Minimal handling during sur-gery. Minimal handling of the donor tooth is crucial to preserve an intact PDL and Hertwig’s epi-thelial root sheath and to prevent compromised root growth leading to resorption, ankylosis, or attach-ment loss.15,16

2. Minimizing the time the donor tooth is out of the mouth.15,16 Kim and colleagues reported no root resorption or ankylosis within their experimental extraoral time of 7.8 minutes.17 These investiga-tors applied a meticulous surgical technique to prevent damage of the PDL and Hertwig’s epithelial root sheath, transplanting the donor teeth to the recipient sites


Fig. 3 Progress records taken eight (panoramic radiograph) and nine months (intraoral photographs) after autotransplantation.


404 JCO/JULY 2011


Fig. 4 A. Patient after 36 months of orthodontic treatment. B. Superimposition of pre- and post-treatment cephalometric tracings.

A B



Fig. 5 A. Patient 12 months after end of treatment. B. Cone-beam computed tomography: multiplanar recon-struction (left and center) and panoramic rendering (right).

A

B

immediately after extraction.

3. Root morphology. The donor tooth should have a conical, smooth root to permit non-trau-matic extraction, thus avoiding damage to the PDL. Successful periodontal healing, completed within two months in most pa -tients,10 is marked by the presence of a lamina dura and absence of root resorption. The fate of a transplanted or reimplanted tooth depends on the viability of the PDL attached to the root.16,18-20

4. Condition of the recipient site. The recipient site should provide enough space for the donor tooth, including adequate height and width of bone. If the buccolingual width is insufficient to accom-modate the donor tooth, there is a risk of alveolar ridge resorption.

5. Donor-tooth fixation. Al -though fixation with sutures pro-vides easy and effective stabiliza-tion of the transplanted tooth in the recipient site, occlusal adjust-ment must be completed before fixation. A splint can permit some movement of the tooth while immobilizing it enough to allow healing. Such minor tooth move-ment can reduce the incidence of ankylosis and minimize adverse effects on periodontal and pulpal healing.21,22

6. Attention to the growth stage of the donor tooth.23 Because there is no root growth after transplantation, autotransplanta-

tion of tooth germs should be performed when root develop-ment has reached 75-100%3-6

(root development stages 3 to 4, on the scale of Moorrees and col-leagues24), with a wide-open api-cal foramen of at least 1mm.25,26

Andreasen and colleagues report-ed that the incidence of pulp necrosis and root resorption was greater in mature premolar trans-plants due to their closed apices. Transplantation of a fully formed root nullifies the potential for pulp regeneration, although endo-dontic therapy will still ensure high survival rates.3-6 In our pa -tient, the donor teeth were trans-planted when root development was about 75% complete. Pulpal healing was achieved because the immature transplanted teeth had wide apical openings.

7. Force application. Ortho-dontic forces should not be applied to a tooth during the first three to six months after the transplantation procedure; when force is eventually applied, the amount and duration should be minimized. According to Hama-moto and colleagues, orthodontic treatment may be initiated shortly after regeneration of the perio-dontal space and radiographic confirmation of the lamina dura.27 In our patient, active orthodontic treatment was begun six months after autotransplantation. At the end of treatment, the crown-to-root ratio of each tooth was ac -

ceptable, and the prognosis of the transplants was good.

Although the closure of our patient’s mandibular central inci-sor spaces prevented us from achieving canine guidance, stud-ies of incisor space closure have found no difference in occlusal function between patients finish-ing with group function and those with canine guidance.28,29 Our patient also required occlusal adjustment to eliminate interfer-ences and premature contacts of the lingual cusps of the trans-planted teeth. Considering the mismatch in tooth morphology between the upper and lower arches, we believe a reasonable esthetic and functional outcome was achieved.

Conclusion

The addition of autotrans-plantation to the orthodontic armamentarium permits tooth movement to contralateral sides of the same dental arch, as well as to the opposite arch. Benefits include reestablishment of a nor-mal alveolar process and bone induction.30 In young patients with missing permanent teeth, the permanent premolars are good candidates for donor teeth while still in their root-formation stage. Even if the transplant ultimately fails, the intact recipient site could subsequently be used for a dental implant.

406 JCO/JULY 2011


1. Slagsvold, O. and Bjercke, B.: Auto-transplantation of premolars with partly formed roots: A radiographic study of root growth, Am. J. Orthod. 66:355-366, 1974.

2. Kristerson, L.: Autotransplantation of human premolars: A clinical and radio-graphic study of 100 teeth, Int. J. Oral Surg. 14:200-213, 1985.

3. Andreasen, J.O.; Paulsen, H.U.; Yu, Z.; Ahlquist, R.; Bayer, T.; and Schwartz, O.: A long-term study of 370 autotrans-planted premolars, Part I. Surgical pro-cedures and standardized techniques for monitoring healing, Eur. J. Orthod. 12:3-13, 1990.

4. Andreasen, J.O.; Paulsen, H.U.; Yu, Z.; Bayer, T.; and Schwartz, O.: A long-term study of 370 autotransplanted pre-molars, Part II. Tooth survival and pulp healing subsequent to transplantation, Eur. J. Orthod. 12:14-24, 1990.

5. Andreasen, J.O.; Paulsen, H.U.; Yu, Z.; and Schwartz, O.: A long-term study of 370 autotransplanted premolars, Part III. Periodontal healing subsequent to transplantation, Eur. J. Orthod. 12:25-37, 1990.

6. Andreasen, J.O.; Paulsen, H.U.; Yu, Z.; and Bayer, T.: A long-term study of 370 autotransplanted premolars, Part IV. Root development subsequent to trans-plantation, Eur. J. Orthod. 12:38-50, 1990.

7. Zachrisson, B.U.: Planning esthetic treatment after avulsion of maxillary incisors, J. Am. Dent. Assoc. 139:1484-1490, 2008.

8. Zachrisson, B.U.; Stenvik, A.; and Haanæs, H.R.: Management of missing maxillary anterior teeth with emphasis on autotransplantation, Am. J. Orthod. 126:284-288, 2004.

9. Stenvik, A. and Zachrisson, B.U.: Ortho dontic closure and transplantation in the treatment of missing anterior teeth: An overview, Endod. Dent. Traumatol. 9:45-52, 1993.

10. Czochrowska, E.M.; Stenvik, A.; Album, B.; and Zachrisson, B.U.: Auto-transplantation of premolars to replace maxillary incisors: A comparison with natural incisors, Am. J. Orthod. 118:592-600, 2000.

11. Slagsvold, O. and Bjercke, B.: Indica-tions for autotransplantation in cases of missing premolars, Am. J. Orthod. 74:241-257, 1978.

12. Slagsvold, O. and Bjercke, B.: Appli-cability of autotransplantation in cases of missing upper anterior teeth, Am. J. Orthod. 74:410-421, 1978.

13. Jonsson, T. and Sigurdsson, T.J.: Autotransplantation of premolars to premolar sites: A long-term follow-up study of 40 consecutive patients, Am. J. Orthod. 125:668-675, 2004.

14. Cohen, A.S.; Shen, T.C.; and Pogrel, M.A.: Transplanting teeth successfully: Autografts and allografts that work, J. Am. Dent. Assoc. 126:481-485, 1995.

15. Thomas, S.; Turner, S.R.; and Sandy, J.R.: Autotransplantation of teeth: Is there a role? Br. J. Orthod. 25:275-282, 1998.

16. Raghoebar, G.M. and Vissink, A.: Results of intentional replantation of molars, J. Oral. Maxillofac. Surg. 57:240-244, 1999.

17. Kim, E.; Jung, J.Y.; Cha, I.H.; Kum, K.Y.; and Lee, S.J.: Evaluation of the prognosis and causes of failure in 182 cases of autogenous tooth transplanta-tion, Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod. 100:112-119, 2005.

18. Nethander, G.: Oral restoration with fixed partial dentures on transplanted abutment teeth, Int. J. Prosthod. 8:517-526, 1995.

19. Tsukiboshi, M.: Autotransplantation of Teeth, Quintessence, Tokyo, pp. 21-55, 2001.

20. Andreasen, J.O. and Kristerson, L.: The effect of limited drying or removal of the periodontal ligament: Periodontal healing after replantation of mature

incisors in monkeys, Acta Odontol. Scand. 39:1-13, 1981.

21. Hernandez, S.L. and Cuestas-Carnero, R.: Autogenic tooth transplantation: A report of ten cases, J. Oral Maxillofac. Surg. 46:1051-1055, 1988.

22. Pogrel, M.A.: Evaluation of over 400 autogenous tooth transplants, J. Oral Maxillofac. Surg. 45:205-211, 1987.

23. Schwartz, O.; Bergmann, P.; and Klausen, B.: Resorption of autotrans-planted human teeth: A retrospective study of 291 transplantations over a period of 25 years, Int. Endod. J. 18:119-131, 1985.

24. Moorrees, J.F.A.; Fanning, E.A.; and Hunt, E.E.: Age variation of formation stages for ten permanent teeth, J. Dent. Res. 42:1490-1502, 1963.

25. Tsukiboshi, M.: Autotransplantation of teeth: Requirement for predictable suc-cess, Dent. Traumatol. 18:157-180, 2002.

26. Northway, W.: Autogenic dental trans-plants, Am. J. Orthod. 121:592-593, 2002.

27. Hamamoto, N.; Hamamoto, Y.; and Kobayashi, T.: Tooth autotransplanta-tion into the bone grafted alveolar cleft: Report of two cases with histologic findings, J. Oral Maxillofac. Surg. 56:1451-1456, 1998.

28. Nordquist, G.G. and McNeill, R.W.: Orthodontic vs. restorative treatment of the congenitally absent lateral incisor—long term periodontal and occlusal evaluation, J. Periodontol. 46:139-143, 1975.

29. Robertsson, S. and Mohlin, B.: The congenital missing upper lateral incisor: A retrospective study of orthodontic space closure versus restorative treat-ment, Eur. J. Orthod. 22:697-710, 2000.

30. Fiorentino, G. and Vecchione, P.: Multiple congenitally missing teeth: Treatment outcome with autologous transplantation and orthodontic space closure, Am. J. Orthod. 132:693-703, 2007.



REFERENCES

autotransplantation of premolars in a patient with …treatment of a patient in the early mixed...

Documents