Title

The Long-Term Survival Rate of Transplanted Maxillary Impacted Canines is High But The Long-Term Success Rate is Low

Clinical Question

What is the long-term prognosis of an impacted maxillary canine that has been transplanted into the arch in a healthy patient?

Clinical Bottom Line

The long-term success rate of impacted maxillary canines that are transplanted was found to be 38% in one study, but the long-term survival rate is high ranging from 83%-93.5%. (See Comments on the CAT below)

Best Evidence

PubMed ID	Author / Year	Patient Group	Study type (level of evidence)
18380551	Arikan/2008	30 healthy patients over the age of 25 with at least one impacted maxillary canine	Prospective, 5-year longitudinal study
Key results	This study only looked at the long-term survival rate of auto-transplanted maxillary canines. They found the survival rate to be 93.5%. The survival rate is defined as the transplanted tooth still present and asymptomatic but may have some root resorption or other clinical factors deeming it unsuccessful. This study had a higher survival rate than other studies. This can be attributed to a few factors such as they required the transplanted tooth to undergo endodontic therapy, which could help reduce the risk of future root resorption. Also, this study had a much shorter follow-up period compared to other studies.
20819783	Patel/2010	191 patients who underwent autotransplantation of impacted maxillary canines with closed apices were asked to participate in this study and a total of 49 patients responded and were included in this study. The average age of these patients at the time of surgery was 21.8 years.	Retrospective
Key results	The survival rate was 83% with an average duration of 14.5 years. The success rate was 38%. The success rate is defined as the transplanted tooth still present, is asymptomatic and has no clinical factors that deem it as unsuccessful. This study didn’t require that the patients have endodontic therapy.

Evidence Search

“autotransplanted” “maxillary” “canines” “success-rate”

Comments on
The Evidence

The studies were well-controlled and followed a strict protocol. The difference in findings suggests that there are several factors that determine whether or not the transplantation will be successful. The age of the patient was found to be a significant factor in the success rate of the surgery. These studies agreed that the younger the patient, the higher the chance of success. Also, performing endodontic therapy seemed to decrease the risk of root resorption and therefore increase the chance of success.

Applicability

Auto-transplantation of impacted maxillary canines can be a good alternative for patients who do not want to undergo lengthy orthodontic treatment or when the position of their impacted canines makes it impossible to bring the tooth in orthodontically. Also, it’s a good interim for patients and buys them time before they have to undergo a more costly procedure such as an implant. There is a definite use for this procedure, but it should be limited to specific cases due to the low long-term success rate.

Specialty

(Oral Surgery) (Orthodontics)

Keywords

impacted tooth, canine tooth, autotransplantation

ID#

880

Date of submission

05/05/2011

E-mail

zirbel@uthscsa.edu

Author

Cassandra Zirbel, DDS

Co-author(s)

Co-author(s) e-mail

Faculty mentor

Peter T. Gakunga, BDS, MS, PhD

Faculty mentor e-mail

GAKUNGA@uthscsa.edu

Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)

None available

Comments and Evidence-Based Updates on the CAT
(FOR PRACTICING DENTISTS', FACULTY, RESIDENTS and/or STUDENTS COMMENTS ON PUBLISHED CATs)

by Kristin Saunders and Wesley Shute (San Antonio, TX) on 10/03/2014
A PubMed search was performed in October 2014 and the 2011 article by Patel is still the most current article. The conclusion regarding clinical applicability remains true: this procedure may provide a positive outcome in cases where orthodontic treatment is not feasible.