Evaluation of Bone Growth around Autotransplanted Teeth Using Cone-Beam Computed Tomographic Images.

INTRODUCTION: The aim of this observational study was to evaluate bone growth at the recipient site of autotransplanted teeth using cone-beam computed tomography (CBCT) images and to compare it to the control tooth. METHODS: Bone growth was measured on CBCT images obtained from the anterior region of the maxilla, which received a single transplant of immature premolars due to early loss of the central incisor. The results were compared to the bone growth of contralateral central incisor that served as control. The sample consisted of 13 autotransplanted teeth and 13 control teeth. It was determined the thickness of the buccal bone of the marginal ridge, the thickness of the palatal bone of the marginal ridge, the height of the maxillary bone, and the thickness of the maxillary bone at its mid-height. The measurements were analyzed statistically, adopting a significance level of 5%. RESULTS: The mean interval between the dental autotransplantation surgery and the CBCT scan was 16.2 years. The mean thickness of the buccal bone of the marginal ridge, thickness of the palatal bone of the marginal ridge, height of the maxillary bone, and thickness of the maxillary bone at its mid-height were, respectively, 0.85, 0.94, 19.6, and 8.85 mm for autotransplanted teeth and 0.79, 1.09, 18.88, and 8.5 mm for control teeth. There were no significant differences in the bone measurements between autotransplanted and control teeth (P > .05). CONCLUSIONS: The growth of maxillary bone in the region that received the autotransplanted tooth was proportional to that of maxillary bone that supports the contralateral tooth. Thus, autogenous transplantation is efficient in maintaining the bone architecture at the recipient site.

An evaluation of 910 premolars transplanted in the anterior region-A retrospective analysis of survival, success, and complications.

AIM: The aim this retrospective analysis was to evaluate the survival, success and possible complications of transplanted premolars to the anterior region subdivided in development stage and patient's age. MATERIALS AND METHODS: The material comprised patients that underwent a tooth transplantation between April 2004 and December 2021. A total of 910 premolars were transplanted in 707 patients. Tooth mobility, oral hygiene, and periodontal parameters were clinically evaluated. Standardized radiographs were used to evaluate pulpal and periodontal healing and root formation. The cumulative survival rate was calculated using the Kaplan-Meier method. RESULTS: The data were subdivided in three groups based on the stage of root development and patient's age. The average age at surgery was 16 years. The main indication for transplantation was trauma, followed by agenesis and other indications. Two premolars were lost during the whole observation period. The overall survival and success in the immature premolars group after an observation period of 10 years was 99.8%. The 10-year survival and success rate when fully developed premolars were transplanted in the anterior region in adolescents were 100% and 96.3%, respectively. In adults, the 10-year survival and success rate were 87.5%. CONCLUSION: Transplantation of premolars with developing and fully developed roots to the anterior region in children, adolescents, and adults is a predictable treatment modality.

An evaluation of 1654 premolars transplanted in the posterior region-A retrospective analysis of survival, success and complications.

AIM: The aim of this retrospective analysis was to evaluate the survival, success and possible complications of transplanted premolars in the posterior region subdivided by developmental stage and patient age. MATERIALS AND METHODS: This study included patients who underwent tooth transplantation between April 2004 and December 2021. A total of 1654 premolars were transplanted into 1243 patients. Tooth mobility, oral hygiene and periodontal parameters were clinically evaluated. Intraoral radiographs were used to evaluate pulpal and periodontal healing, and root formation. The cumulative survival rate was calculated using the Kaplan-Meier method. RESULTS: Data were subdivided into three groups based on the stage of root development and patient age. The mean age at surgery was 14.5 years. The main indication for transplantation was agenesis, followed by trauma and other indications, such as impacted or malformed teeth. A total of 11 premolars were lost during the study period. The overall survival and success rates in the immature premolar group after an observation period of 10 years were 99.7% and 99.4%, respectively. High survival and success rates (95.7% and 95.5%, respectively) were also observed when fully developed premolars were transplanted into the posterior region of adolescents. In adults, the success rate after 10-year follow-up is 83.3%. CONCLUSIONS: Transplantation of premolars with developing and fully developed roots is a predictable treatment modality.

Survey of patients and parents on the autotransplantation of developing premolars to replace traumatised maxillary incisors.

BACKGROUND/AIM: There is a little research on the experiences and opinions of patients who have had autotransplantation of a tooth. The aim of the study was to assess the satisfaction of patients who underwent the autotransplantation of a developing premolar to replace a traumatised maxillary central incisor. MATERIALS AND METHODS: Eighty patients (with a mean age of 10.7-years) and 32 parents were surveyed with 13 and 7 questions, respectively, to determine their opinions about the surgery, post-operative period, orthodontic and restorative treatment they had received. RESULTS: Patients and their parents were very satisfied with the outcomes of the autotransplantation treatment. The majority of patients and all parents declared that they would choose this treatment again if needed. Patients who already had aesthetic restoration of the transplanted toothscored significantly better in position, similarity to other teeth, alignment and aesthetics, when compared to patients before restoration of the premolar to the shape of incisor. Patients after orthodontic treatment considered the alignment of the transplanted tooth between the adjacent teeth as better when compared to patients before or during their orthodontic treatment. CONCLUSIONS: Autotransplantation of developing premolars to replace traumatized maxillary central incisors proved to be a well-accepted treatment option. A delay of restoration of the transplanted premolars to the shape of the maxillary incisors did not have a negative impact on the satisfaction with the treatment.

The outcomes of auto-transplanted premolars in the anterior maxilla following traumatic dental injuries.

BACKGROUND/AIMS: Tooth auto-transplantation is a treatment option, which is often not considered to replace anterior maxillary incisors in children and adolescents. There are multiple prognostic factors that may influence the outcomes of premolar auto-transplantation, but there is limited evidence from human studies. The aim of this study was to report the outcomes of auto-transplanted premolars in the anterior maxilla following traumatic dental injuries (TDIs) and to identify their prognostic factors. MATERIALS AND METHODS: The clinical records of patients who had premolars transplanted in the anterior maxilla following TDI, with appropriate radiographs and a minimal of 1-year follow-up, were reviewed retrospectively. A specific data extraction form was developed, tested and used to collect information for the prognostic factors and outcomes. RESULTS: The cohort included 120 patients with 144 auto-transplanted premolars. The mean age was 12.2 years (±2.0), and the mean observation period was 3.7 years (±1.8). The success rate was 80%, and the survival rate was 93%. Unfavourable outcomes included external replacement resorption in 12.5%, uncontrolled external inflammatory resorption in 2.7%, and both resorption types in 4.9% of teeth. Periodontal healing was significantly associated with donor tooth root maturity, graft handling at the time of surgery including ease of donor tooth extraction and placement at the recipient sites, recipient site alveolar bone status, and post-operative transplant mobility. Seventy-four teeth (53.4%) were immature at the time of transplantation where pulp revascularisation was anticipated, and 52 (70%) of those had radiographic and clinical signs of pulp healing. Pulp healing was significantly related to donor tooth eruption stage, ease of extraction of donor tooth, and ease of placement in the recipient site. CONCLUSIONS: Good outcomes were observed for premolar teeth auto-transplanted in the anterior maxilla. The main prognostic factors were ease of extraction of donor tooth and ease of placement in the recipient sites and donor tooth root maturity.

Enhanced socket preparation during autotransplantation: a new treatment protocol.

OBJECTIVE: Tooth autotransplantation (AT) is a viable option for the replacement of unrestorable or missing teeth. Recently, the use of a 3D replica of a donor tooth constructed from CBCT scans was described. The model is made to assess the recipient site's size and minimize the required extraoral time of the donor tooth after extraction. The aim of the paper was to describe a new technique for AT using the 3D replica as a socket preparation tool. CASE REPORT: A 13-year-old boy who presented with hypodontia was referred for consultation and treatment. The treatment plan included combined orthodontic treatment and AT of the mandibular left second premolar into the site of the congenitally missing maxillary right canine. A titanium 3D model of the donor tooth was printed by a direct metal laser 3D printer utilizing the model from the CBCT scan. An intrasulcular flap was elevated, and the edentulous maxillary ridge was prepared using implant trephine burs with increasing diameters. A surgical mallet was utilized to apply vertical forces to the 3D-printed model, which was inserted into the prepared socket to allow a perfect fit for the donor tooth. After atraumatic extraction of the mandibular left second premolar, the donor tooth was inserted into the ready socket and splinted. Follow-up examinations at 1, 3, and 6 months, and 1 year after surgery demonstrated a successful outcome. CONCLUSION: The titanium replica was successfully used for precise preparation of the recipient site, minimizing the extraoral time of the procedure to 4 minutes, and thereby improving the expected outcome. (Quintessence Int 2023;54:142-148; doi: 10.3290/j.qi.b3649031).

Long-term outcomes 1-20 years after autotransplantation of teeth: clinical and radiographic evaluation of 66 premolars and 8 molars.

In this retrospective study we investigated the long-term survival of autotransplanted premolars and molars with incompletely developed roots. The presence of the transplanted teeth and their outcome after autotransplantation was ascertained from clinical and radiographic evaluation by a maxillofacial surgeon or dentist. Kaplan Meier survival curves were estimated for the total population and for the two groups (premolars and molars). Fifty-one patients with 74 transplanted teeth were included, and the median duration of follow-up was 10 (range 1-20) years. Four of 66 premolars and one of 8 molars were removed and the cumulative survival was 95.4% (95% CI 90.3 to 100). The difference in survival between the premolars and molars was not significant. These results show that the long-term survival of autotransplanted teeth is good. Replacement of a single tooth by autotransplantation should therefore always be considered and is preferred when a suitable donor tooth is available.

Patient with asymmetric multiple hypodontia treated with autotransplantation of 2 premolars.

Tooth autotransplantation is performed in patients with congenitally missing teeth and those with traumatic tooth loss. We report a course of edgewise treatment of a girl with multiple congenitally missing teeth and residual features of ectodermal dysplasia, who was treated with autotransplantation of 2 premolars with developing roots. She was 8 years old at the beginning of the treatment. No signs of inflammation, root resorption, or pulp symptoms were observed during the 2.5 years of edgewise treatment after autotransplantation. Cervical external root resorption was detected 31 months postoperatively in 1 transplanted tooth (maxillary first premolar), and the same problem occurred in the other transplanted tooth (mandibular second premolar) 2 years later. Root canal treatment was immediately undertaken and resulted in inhibition of further pathology. Consequently, the survival of both transplanted teeth was achieved. The orthodontic treatment that included intervals related to diagnosis and treatment of root resorption of the transplanted premolars is described in detail.

Autotransplantation of premolars: does surgeon experience matter?

Autotransplantation of premolars is a well-established method to rehabilitate aplasia of premolars. Nevertheless, with the introduction of titanium implants, not all surgical units offer this procedure. The aim of this study was to examine the predictability of autotransplantation of premolars on orthodontic indication as suggested by Andreasen et al., when performed by surgeons with or without prior experience of this procedure. A prospective protocol was implemented in 2001. All patients treated with autotransplantation of premolars during the years 2001-2015 were recalled to evaluate the long-term status of the teeth. The state of root development, need for endodontic treatment, presence of an apical pathology or ankylosis, and tooth loss were recorded. The results were divided into two groups according to the surgeon's experience: senior surgeons with prior training and experience in the procedure and junior surgeons without prior experience. A total of 89 teeth (66 patients) were treated. The mean observation time was 10.1 years (range 1.0-15.1 years). The long-term survival rate was 95%. No statistically significant difference between the results of the two groups of surgeons was found. Autotransplantation of premolars on orthodontic indication could be adopted successfully in the hospital setting regardless of surgeon experience.

Computerized three-dimensional design for accurate orienting and dimensioning artificial dental socket for tooth autotransplantation.

OBJECTIVE: To present an improved, accurate, and efficient method for planning and preparing an artificial socket for autotransplantation, by using a three-dimensional (3D) surgical guide and a replica of the transplanted donor tooth. The guide and the tooth replica were fabricated using a computerized 3D simulation. A case treated with this approach is presented. METHOD AND MATERIALS: Cone beam computed tomography (CBCT) and computerized 3D simulations (Simplant plus registration as stereolithography) were used for planning the optimal artificial socket position and dimensions, within the limitations of the alveolar bone borders and the adjacent teeth roots, and for producing a metal replica of the transplanted tooth. The replica was used to assure the correct socket preparation and orientation before extraction and replantation of the donor premolar. RESULTS: The entire procedure time for autotransplantation of a permanent second premolar to the incisor site without the buccal plate was about 45 minutes. At 15 months' follow up, clinical examination of the transplanted tooth demonstrated both normal mobility and no sensitivity to cold stimulation. A radiographic examination revealed continuous root development and pulp obliteration. The adjacent teeth maintained their vitality with no pathologic signs. CONCLUSION: We present an improved technique for autotransplantation based on computerized 3D simulations and guidance for accurate dimensioning and optimal locating of the artificial socket relative to the alveolar bone borders and the adjacent teeth roots. This technique may significantly simplify the autotransplantation procedure and will probably also increase its success rate and use in young patients, even in cases with absence of a buccal plate.

National clinical guidelines for the management of unerupted maxillary incisors in children.

This article summarises recently updated guidelines produced by the Clinical Governance Directorate of the British Orthodontic Society through the Clinical Standards Committee of the Faculty of Dental Surgery, Royal College of Surgeons of England (FDSRCS) on the management of unerupted maxillary incisor teeth in children. The maxillary incisor teeth usually erupt in the early mixed dentition but eruption disturbances can occur and are often attributable to local factors. A failure of eruption will affect the developing occlusion and potentially influence psychological development of the child. The general principles of management for delayed eruption or impaction of these teeth is to ensure that adequate space exists in the dental arch and to remove any obstruction to eruption. Consideration should also be given to further promoting eruption through surgical exposure of the incisor, with or without subsequent orthodontic traction. A number of factors influence the decision-making process, including patient age, medical history, potential compliance, aetiology and position of the unerupted incisor. Treatment planning should be complemented by careful clinical assessment and the use of appropriate special investigations. To optimise the treatment outcome a multidisciplinary specialist approach is recommended.

Premolar autotransplantation in juvenile dentition: quantitative assessment of vertical bone and soft tissue growth.

OBJECTIVE: Premolar autotransplantation represents an effective therapeutic option for the treatment of juvenile dentition with either aquired or congenital hypodontia. The objective of this prospective clinical study was to quantitatively assess bone and soft tissue levels after autogenous premolar transplantation by clinical and radiographic parameters. STUDY DESIGN: In the study, 26 premolars were transplanted in 20 patients after traumatic tooth loss (n = 16) or congenital aplasia (n = 10) in the anterior maxilla. Based on standardized photographic documentation, the relative soft tissue level was measured compared to the healthy adjacent teeth. Radiographic findings included evaluation of root resorption, pulp canal obliteration, and relative bone height. RESULTS: Average survival rate of transplanted premolars (n = 26) was 100% over a follow-up period of 29 months (range 10-60 months). The relative soft tissue level significantly increased by +1.1 mm (P < .01). Radiographs showed a tendency toward vertical bone growth. Continuous root development and signs of pulpal healing were observed postoperatively in 18 transplants (69.2%). CONCLUSIONS: Autogenous premolar transplantation represents a safe method to ensure functional and aesthetic rehabilitation in the anterior maxilla irrespective of the nature of tooth loss.

Guided Autotransplantation of Teeth: A Novel Method Using Virtually Planned 3-dimensional Templates.

INTRODUCTION: The aim of this study was to introduce an innovative method for autotransplantation of teeth using 3-dimensional (3D) surgical templates for guided osteotomy preparation and donor tooth placement. METHODS: This report describes autotransplantation of immature premolars as treatment of an 11-year-old boy having suffered severe trauma with avulsion of permanent maxillary incisors. This approach uses modified methods from guided implant surgery by superimposition of Digital Imaging and Communications in Medicine files and 3D data sets of the jaws in order to predesign 3D printed templates with the aid of a fully digital workflow. RESULTS: The intervention in this complex case could successfully be accomplished by performing preplanned virtual transplantations with guided osteotomies to prevent bone loss and ensure accurate donor teeth placement in new recipient sites. Functional and esthetic restoration could be achieved by modifying methods used in guided implant surgery and prosthodontic rehabilitation. The 1-year follow-up showed vital natural teeth with physiological clinical and radiologic parameters. CONCLUSIONS: This innovative approach uses the latest diagnostic methods and techniques of guided implant surgery, enabling the planning and production of 3D printed surgical templates. These accurate virtually predesigned surgical templates could facilitate autotransplantation in the future by full implementation of recommended guidelines, ensuring an atraumatic surgical protocol.

EDTA soluble chemical components and the conditioned medium from mobilized dental pulp stem cells contain an inductive microenvironment, promoting cell proliferation, migration, and odontoblastic differentiation.

BACKGROUND: The critical challenge in tissue engineering is to establish an optimal combination of stem cells, signaling morphogenetic molecules, and extracellular matrix scaffold/microenvironment. The extracellular matrix components of teeth may be reconstituted as an inductive microenvironment in an ectopic tooth transplantation bioassay. Thus, the isolation and identification of the chemical components of the inductive microenvironment in pulp/dentin regeneration will accelerate progress towards the goal of tissue engineering of the tooth. METHODS: The teeth demineralized in 0.6 M hydrochloric acid were sequentially extracted by 4.0 M guanidine hydrochloride (GdnHCl), pH 7.4, and 0.5 M ethylenediaminetetraacetic acid (EDTA), pH 7.4. The extracted teeth were transplanted into an ectopic site in severe combined immunodeficiency (SCID) mice with mobilized dental pulp stem cells (MDPSCs). The unextracted tooth served as a positive control. Furthermore, the soluble components for the inductive microenvironment, the GdnHCl extracts, or the EDTA extracts together with or without MDPSC conditioned medium (CM) were reconstituted systematically with autoclaved teeth in which the chemical components were completely inactivated and only the physical microenvironment was preserved. Their pulp/dentin regenerative potential and angiogenic potential were compared 28 days after ectopic tooth transplantation by histomorphometry and real-time RT-PCR analysis. RESULTS: Expression of an odontoblastic marker, enamelysin, and a pulp marker, thyrotropin-releasing hormone degrading enzyme (TRH-DE), was lower, and expression of a periodontal cell marker, anti-asporin/periodontal ligament-associated protein 1 (PLAP-1), was higher in the transplant of the EDTA-extracted teeth compared with the GdnHCl-extracted teeth. The autoclaved teeth reconstituted with the GdnHCl extracts or the EDTA extracts have weak regenerative potential and minimal angiogenic potential, and the CM significantly increased this potential. Combinatorial effects of the EDTA extracts and the CM on pulp/dentin regeneration were demonstrated in vivo, consistent with their in-vitro effects on enhanced proliferation, migration, and odontoblastic differentiation. CONCLUSIONS: The EDTA-extracted teeth demonstrated significantly lower pulp/dentin regenerative potential compared with the GdnHCl-extracted teeth. The EDTA soluble chemical components when reconstituted with the physical structure of autoclaved teeth serve as an inductive microenvironment for pulp/dentin regeneration, promoting cell proliferation, migration, and odontoblastic differentiation.

Autotransplantation of Premolars With a 3-Dimensional Printed Titanium Replica of the Donor Tooth Functioning as a Surgical Guide: Proof of Concept.

PURPOSE: Autotransplantation of premolars is a good treatment option for young patients who have missing teeth. This study evaluated the use of a preoperatively 3-dimensional (3D)-printed replica of the donor tooth that functions as a surgical guide during autotransplantation. MATERIALS AND METHODS: Five consecutive procedures were prospectively observed. Transplantations of maxillary premolars with optimal root development were included in this study. A 3D-printed replica of the donor tooth was used to prepare a precisely fitting new alveolus at the recipient site before extracting the donor tooth. Procedure time, extra-alveolar time, and number of attempts needed to achieve a good fit of the donor tooth in the new alveolus were recorded. RESULTS: For each transplantation procedure, the surgical time was shorter than 30 minutes. An immediate good fit of the donor tooth in the new alveolus was achieved with an extra-alveolar time shorter than 1 minute for all transplantations. CONCLUSION: These results show that the extra-alveolar time is very short when the surgical guide is used; therefore, the chance of iatrogenic damage to the donor tooth is minimized. The use of a replica of the donor tooth makes the autotransplantation procedure easier for the surgeon and facilitates optimal placement of the transplant.

Autotransplantation of premolars to the maxillary incisor region: a long-term follow-up of 12-22 years.

OBJECTIVE: To investigate the long-term outcome of treatment of missing maxillary incisor teeth by transplantation of premolars, with special reference to aesthetics and patient satisfaction. SUBJECTS AND METHODS: Twenty subjects who had undergone transplantation of premolars to the maxillary incisor area were recalled for follow-up varying between 12 and 22 years post-surgery. Twelve subjects presented for examination, including radiography and three subjects participated only by answering questions. Three reference groups-general practitioners, orthodontists, and lay people-evaluated the aesthetic results from photographs. Patient satisfaction was evaluated by interviews and OHIP-14. RESULTS: The mean age at transplantation was 12.3 years: 1 subject had been 20 years old and 11 were in the range of 9-14 years. Twelve to 22 years after autotransplantation, 5 subjects could not be reached: of the 15 who could be contacted, the survival rate was 15 out of 15. In the 12 subjects who presented for clinical examination, 11 out of the 12 transplants were assessed as successful. Nine transplants were restored with crowns and five had been recontoured with composite build-ups. In one patient, no restorative treatment had been undertaken. The subjects were satisfied with the aesthetic result. CONCLUSION: Autotransplantation of premolars is an appropriate method for treatment of missing maxillary anterior teeth. Subjects with a transplanted tooth to the maxillary anterior region perceive their oral health as good long term.

Nasomaxillary hypoplasia with a congenitally missing tooth treated with LeFort II osteotomy, autotransplantation, and nickel-titanium alloy wire.

INTRODUCTION: In some skeletal Class III adult patients with nasomaxillary hypoplasia, the LeFort I osteotomy provides insufficient correction. This case report describes a 20-year-old woman with a combination of nasomaxillary hypoplasia and a protrusive mandible with a congenitally missing mandibular second premolar. METHODS: We performed a LeFort II osteotomy for maxillary advancement. Autotransplantation of a tooth was also performed; the donor tooth was used to replace the missing permanent tooth. To increase the chance of success, we applied light continuous force with an improved superelastic nickel-titanium alloy wire technique before extraction and after transplantation. RESULTS: The patient's profile and malocclusion were corrected, and the autotransplanted tooth functioned well. The postero-occlusal relationships were improved, and ideal overbite and overjet relationships were achieved. CONCLUSIONS: The methods used in this case represent a remarkable treatment.

A case of tooth autotransplantation after long-term cryopreservation using a programmed freezer with a magnetic field.

This case report describes the treatment of a skeletal Class III malocclusion with autotransplantation of a cryopreserved tooth. To gain an esthetic facial profile and good occlusion, extraction of bimaxillary premolars and surgical therapy were chosen. The patient had chronic apical periodontitis on the lower left first molar. Although she did not feel any pain in that region, the tooth was considered to have a poor prognosis. Therefore, we cryopreserved the extracted premolars to prepare for autotransplantation in the lower first molar area because the tooth would probably need to be removed in the future. The teeth were frozen by a programmed freezer with a magnetic field (CAS freezer) that was developed for tissue cryopreservation and were cryopreserved in -150°C deep freezer. After 1.5 years of presurgical orthodontic treatment, bilateral sagittal split ramus osteotomy was performed for mandible setback. Improvement of the facial profile and the occlusion were achieved in the retention phase. Six years after the initial visit, the patient had pain on the lower left first molar, and discharge of pus was observed, so we extracted the lower left first molar and autotransplanted the cryopreserved premolar. Three years later, healthy periodontium was observed at the autotransplanted tooth. This case report suggests that long-term cryopreservation of teeth by a CAS freezer is useful for later autotransplantation, and this can be a viable technique to replace missing teeth.