A long-term study of 370 autotransplanted premolars. Part II. Tooth survival and pulp healing subsequent to transplantation

Transient Apical Breakdown: Incidence, Pathogenesis, and Healing

BACKGROUND/AIMS

Transient apical breakdown (TAB) is a phenomenon that indicates temporary apical periodontal destruction and root resorption after tooth luxation injuries, followed by the healing process of the dental pulp. Andreasen in 1986, reported that TAB was seen in approximately 4.2% of all luxation injuries. However, there have been no reports thereafter on the types and frequency of the luxation traumatic injuries in which TAB occurs. Therefore, this retrospective study was aimed to assess the incidence and pathogenesis of dental trauma-induced TAB and to suggest a possible mechanism of subsequent healing based on a series of cases.

METHODS

Data analysis included mature teeth (n = 56) of 49 patients aged 9-30 years who presented in a private dental office over a period of 10 years (2012-2022) to investigate the incidence and healing sequala of TAB.

RESULTS

TAB was observed in 43.8% of subluxation, 62.5% of extrusive luxation, and 75% of lateral luxation injuries. The average age of patients who developed TAB was 14.5 years, ranging from 9 to 28 years old.

CONCLUSIONS

TAB can be expected in many cases of luxation injuries with minimal dislocation. Therefore, mild injuries (subluxation, extrusion, and lateral luxation), may exhibit spontaneous healing, recovery of dark discoloration of the crown, disappearance of a periapical radiolucent lesion and return to normal response to EPT as long as 12 months after the traumatic injury. Thus, a decision to perform endodontic treatment in these cases might be postponed until clear evidence for an infection exists.

"In Their Own Words": Families' Experiences With Tooth Autotransplantation for the Replacement of Maxillary Incisors in Children

OBJECTIVES

To examine families' experiences, including motivation and barriers to undergoing tooth autotransplantation (AT), and their perceptions of associated esthetic and functional outcomes.

METHODS

Semi-structured, in-depth-interviews (IDIs) were conducted in person with families who had children that underwent the AT procedure. Interviews were audio recorded and transcribed. Transcripts were coded and thematically analyzed both deductively and inductively. A facilitators and barriers matrix and journey maps were created to draw inferences on patterns arising from main themes.

RESULTS

Twenty families selecting AT as a solution for a missing maxillary incisor were recruited and interviewed. Overall, all families interviewed had a positive experience with the AT procedure. Motivating factors for undergoing the AT procedure included wanting an earlier intervention for the missing incisor, wishing to mitigate negative psychosocial effects, and the anticipated positive outcomes that would last into adulthood. Barriers to uptake of the AT procedure included the lack of dental practitioner awareness of AT as a potential solution and a large number of appointments and travel. Families were also initially concerned over potential complications that could arise from their child undergoing this procedure. The cost of the procedure was both a barrier and a facilitator for treatment.

CONCLUSIONS

The study results demonstrate that the overall AT is favorably considered by the families of growing children for the replacement of maxillary incisors and highlight factors that may act as motivators or barriers to its uptake.

Digital Simulation and Designing of a Novel Osteotomy Guide for Autotransplantation in the Anterior Region

Autotransplantation of teeth (ATT) is a viable treatment option for replacing teeth lost due to various reasons. Periodontal ligament (PDL) on the donor tooth is one of the most crucial factors determining the success of ATT. To preserve the PDL during surgery and improve the success rate of ATT, digital dentistry has been applied to ATT. In this article, a digital workflow including surgical simulation, a three-dimensional (3D) replica fabrication, and a novel osteotomy guide design is introduced. Digital simulation of ATT on a patient's integrated model enables visualization of anatomical structures and the 3D position of the donor tooth prior to the actual surgery. The 3D-printed osteotomy guide allows the transfer of the direction and depth of the planned osteotomy into the intraoral environment. The 3D replica helps prepare the recipient site before the actual transplantation, which minimizes the extra-alveolar time of the donor tooth and decreases trauma during the try-in process. The proposed virtual planning and the use of the guide and the 3D replica can facilitate the surgical procedures while minimizing complications.

Tooth autotransplantation with adjunctive application of enamel matrix derivatives using a digital workflow: A prospective case series

OBJECTIVES

Digital protocols and bioactive materials may reduce complications and improve tooth autotransplantation (ATT) success and survival rates. This prospective study assesses the performance of a fully digital autotransplantation protocol of close-apex molars with the adjunctive application of Enamel Matrix Derivatives (EMD).

METHODS

Twelve adult patients with 13 hopeless molar teeth were replaced with autotransplantation of closed apex third molars. Outcomes, including success and survival rates, clinical, endodontic, radiographic, patient-reported outcome measures (PROMs), and digital image assessments, were conducted over a two-year follow-up period.

RESULTS

Survival and success rates were 100% and 91.2%, respectively, with no progressive inflammatory or replacement root resorption (ankylosis) except for one tooth presenting radiographic furcation involvement. A significant probing depth reduction of 2.4 ± 2.58 mm and CAL gains of 2.8 ± 3.03 mm were observed in transplanted teeth compared to the hopeless receptor teeth. Radiographic bone levels remained stable throughout the study period (-0.37 ± 0.66 mm), and digital image assessments showed minimal alveolar ridge width changes (-0.32 to -0.7 mm) and gingival margin changes (-0.95 to -1.27 mm) from baseline to last visit. PROMs indicated very high patient satisfaction.

CONCLUSION

The use of a digital ATT protocol with adjunctive use of EMD in closed-apex third molars demonstrated promising short-term high success and survival rates. Additionally, this type of therapy adequately preserves the dimensions of the alveolar ridge in the receptor site.

CLINICAL SIGNIFICANCE

This is the first prospective clinical study examining the effect of a digital tooth autotransplantation protocol combined with the application of EMD. It demonstrates that this approach is an effective treatment for replacing hopeless teeth and also validates the digital assessment of ATT alveolar ridge preservation at the recipient site.

Autologous Tooth Transplantation in Craniofacial Malformations

OBJECTIVE

To evaluate the applicability of transplanted teeth in young patients with craniofacial anomalies.

DESIGN

Observational study.

SETTING

Comprehensive Centre for Cleft Palate and Craniofacial Malformations.

PATIENTS/PARTICIPANTS

Patients with craniofacial anomalies who underwent tooth transplantation. Only children with complete clinical and radiological documentation and a follow-up period of at least 1.5 years were included.

INTERVENTIONS

Tooth transplantation.

MAIN OUTCOME MEASURE(S)

Retrospective evaluation of clinical records, pre- and postoperative radiographs, and operative charts. Clinical characteristics of patients, preoperative parameters and postoperative outcome parameters were collected.

RESULTS

A total of 17 patients with 23 tooth transplantations were included. The median follow-up period was 6.7 years. The pooled survival and success rates were 91%. Notably, one out of two teeth that were transplanted into the bone grafted alveolar cleft site had to be extracted, which might indicating a higher risk for this procedure. In total, two transplanted teeth had to be extracted during the follow-up period, one due to external resorption and the other one due to perio-endo lesion. One patient needed endodontic treatment due to pulp necrosis.

CONCLUSION

We consider tooth transplantation to be a reliable and suitable procedure in the dental rehabilitation of young patients with craniofacial anomalies and fitting concomitant circumstances. We encourage craniofacial teams to reconsider this option more frequently in appropriate cases.

Tooth Autotransplantation, Autogenous Dentin Graft, and Growth Factors Application: A Method for Preserving the Alveolar Ridge in Cases of Severe Infraocclusion-A Case Report and Literature Review

Background: Tooth infraocclusion is a process in which a completely or partially erupted tooth gradually moves away from the occlusal plane. Submerged teeth can lead to serious complications. Treating teeth with infraocclusion is very challenging. One of the procedures allowing for the replacement of a missing tooth is autotransplantation. The aim of this paper is to review the literature on teeth autotransplantation, supported by a case report involving the autotransplantation of a third mandibular molar into the site of an extracted infraoccluded first mandibular molar, as well as the utilization of advanced platelet-rich fibrin (A-PRF) alongside autogenous dentin grafts for bone tissue regeneration. Methods: A severely infraoccluded first permanent right mandibular molar was extracted and then ground to obtain the dentin graft. A-PRF clots (collected from the patient's peripheral blood) were added to the autogenous dentin graft, to create the A-PRF membrane. An atraumatic extraction of the lower left third molar was performed and then it was transplanted into the socket of tooth no. 46. Immediately after transplantation, tooth no. 38 was stabilized with orthodontic bracket splints for 3 months. The patient attended regular follow-up visits within 12 months. Results: After one year, the patient did not report any pain. In the clinical examination, the tooth and surrounding tissues did not show any signs of infection. However, radiographically, cervical inflammatory resorption, unchanged pulp canal dimensions, absent root growth, periapical radiolucency, and lack of apical and marginal healing were observed. Reconstruction of the bone defect was obtained and the alveolar ridge of the mandible was preserved. Due to poor stability of the tooth and severe resorption, the tooth needed to be extracted. Conclusions: This study is designed to critically evaluate the efficacy of autotransplantation, the application of growth factors, and the integration of autogenous dentin grafts in remedying dental deficiencies resulting from reinclusion. We aim to point out the possible causes of treatment failure.

Nonextraction Treatment of Maxillary Canine and Lateral Incisor Transposition: A Case Report

The transposition of teeth is an infrequent dental abnormality characterized by the exchange of position between two adjacent teeth. This report presents a unique case of transposition involving the maxillary right canine and lateral incisor in a 20-year-old female patient. Clinical assessment and radiographic evaluation revealed the unconventional positioning of the affected teeth. Treatment planning necessitated collaborative efforts between orthodontic specialists to achieve optimal esthetic and functional outcomes. The patient underwent a comprehensive treatment regimen, including orthodontic alignment by distal drifting of the canine and mesial shifting of the lateral incisor. Subsequent long-term follow-ups confirmed stable occlusion and satisfactory esthetics in a time period of 18 months. This case underscores the significance of precise diagnosis and a multidisciplinary approach in managing intricate dental anomalies such as tooth transposition.

Advancements in tooth autotransplantation

BACKGROUND

Tooth autotransplantation (AT) involves the surgical relocation of a tooth from 1 site in the mouth to another site within the same patient. This approach is a good option in a growing patient when dental implant placements or fixed bridges are not suitable and when preserving natural teeth is a priority. Tooth AT is a complex procedure that requires specialized skills from a multidisciplinary team with careful patient and tooth selection and treatment planning.

TYPES OF STUDIES REVIEWED

The authors provided a review of the state of knowledge and research on tooth AT and presented a case scenario and barriers to adoption, with a focus on the United States.

RESULTS

Success rates for tooth AT can vary depending on several factors, including the patient's overall health, specific tooth involved, skill of the dental surgeon, and postoperative care provided. Long-term outcomes of autotransplanted teeth have been cited in the literature with impressive longitudinal follow-up spanning up to 26 years. Results of several systematic reviews showed survival rates from 75% through 98%.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Adoption of tooth AT has grown over the years, owing to advancements in dental techniques, improved patient outcomes, and increased awareness among both dentists and patients. Increasing awareness and availability of tooth AT to replace missing teeth can provide a natural and functional alternative to traditional prosthetic options. Tooth AT helps preserve the alveolar bone in growing patients and can offer excellent esthetic and functional outcomes.

Successful auto-transplantation of a mandibular third molar: A case report on restoring esthetics and function in a 66-year-old patient

Key Clinical Message

This article describes a successful case of auto-transplantation of a mandibular third molar to replace a non-restorable second molar, highlighting the efficacy of this procedure in restoring function with factors like asepsis, surgical technique, and postoperative care contributing to the success.

Abstract

This case report describes successful auto-transplantation of a mandibular third molar to replace a non-restorable second molar in a 66-year-old patient. The procedure involved atraumatic extraction, repositioning, and stabilization of the donor tooth, followed by postoperative care and 1-year follow-up. The favorable outcome highlights the potential of mature third molar transplantation as an effective approach for replacement of missing or non-restorable permanent molar teeth to restore esthetics and function. The success of the procedure was attributed to factors such as asepsis, atraumatic surgical technique, preservation of the periodontal ligament (PDL) vitality, minimal extraoral time, optimal occlusion, and adequate fixation. At the 1-year follow-up, the patient was asymptomatic with stable occlusion, highlighting the optimal efficacy of the procedure.

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.

Survival of retained permanent canines after autotransplantation: A retrospective cohort study

INTRODUCTION

After third molars, canines are the teeth most commonly affected by displacement and impaction. Although orthodontic surgical treatment represents the standard method for realignment of canines, autotransplantation (autoTX) functions as the second-line therapy if orthodontic alignment does not succeed in treating impaction and severe displacement. This retrospective cohort study aimed to identify clinical predictors for postoperative survival and endodontic treatment needs after autoTX of severely displaced and impacted canines.

METHODS

The study cohort comprised patients who received canine autoTX in a single surgical center between 2006 and 2018. Canines with severe displacement and retention were surgically treated using a standardized protocol. Statistical analysis of survival probability was performed with the Kaplan-Meier method, and bivariate data were analyzed using logistic regression and the Pearson chi-square test. Nonparametric continuous variables were analyzed using the Mann-Whitney U test.

RESULTS

Data from 319 patients with 378 canine grafts were available for analysis after a mean follow-up of 54.7 ± 36.5 months on the patient level (range, 0.3-181.8 months). With 25 lost autotransplants, the cumulative survival rate was 93.4%. Patient age at surgery, the state of the apical foramen, endodontic treatment need, and persistence of deciduous teeth at the implantation site had a significant negative impact on autotransplant survival (P <0.05). Endodontic treatment need was significantly related to the patient's age at surgery, the state of the apical foramen, and preoperative orthodontic traction (P <0.05). Thus, these independent variables were identified as clinical predictors for the survival of both the autotransplant and the dental pulp. Gender, ischemia time, postoperative ankylosis, or site of autoTX did not influence any of the outcome variables.

CONCLUSIONS

The high survival rates of autotransplanted permanent canines make this treatment a promising option, especially in patients with severe tooth displacement, in which orthodontic treatment alone cannot provide predictable alignment, irrespective of the patient's age. Interpreting age and preoperative orthodontic traction as delaying the onset of autoTX and state of apex, time-dependent aspects seem to be of great importance for postoperative complications leading to endodontic treatment or graft loss. Therefore, early implementation of autoTX as a treatment modality for impacted, severely displaced, and vain exposed canines in daily surgical practice should be encouraged.

Effect of 3D printed replicas on the duration of third molar autotransplantation surgery: A controlled clinical trial

BACKGROUND/AIM

This study aimed to develop a protocol that combines cone-beam computed tomography (CBCT), software, and 3D printing to design 3D replicas for tooth autotransplantation. The goal was to evaluate the impact of this approach on the extraoral time of the donor teeth and the total surgical time, thereby enhancing surgical efficiency and outcomes.

MATERIALS AND METHODS

A non-randomized trial (protocol 10.1186/ISRCTN13563091) was conducted at Riga Stradins University, enrolling 46 patients (13-22 years old) who required molar extraction and possessed a non-erupted third molar. The patients were sequentially assigned to a 3D replica group (24 patients) or a control group (22 patients). The primary outcome measured was the extra-alveolar time of the donor tooth, and the secondary outcome was the total duration of surgery. Both were assessed using a sample size capable of detecting a 10-min difference. A generalized linear model adjusted for various factors was used to test for significant time differences (p < .05) between the groups.

RESULTS

Forty-six patients were included in this analysis. The effect of using 3D replicas was not statistically significant and was associated with a decrease in the extraoral time of the donor tooth in seconds (β = -9.35, 95% CI [-40.86, 22.16]). For the total surgical time in minutes, the use of 3D replicas had a statistically significant impact, reducing the operation duration in minutes (β = -13.42, 95% CI [-24.50, -2.34]). No early complications were observed in either group, with all teeth present at 3-4 weeks post-surgery.

CONCLUSIONS

The integration of 3D printing technology can enhance the efficiency of autotransplantation surgeries, primarily by reducing surgical time.

Multiple effects of dose-related GM-CSF on periodontal resorption in deep-frozen grafted teeth: A reverse study

Autologous tooth grafting is a dental restorative modality based on periodontal ligament healing.Human periodontal ligament stem cells(PDLSCs) are involved in the formation and remodeling of periodontal tissue.Based on previous findings, the proliferation and differentiation of processing cryopreserved periodontal ligament stem cells (PDLSCs) exhibit similarities to those of fresh cells. However, there is evident absorption in the transplanted frozen tooth's roots and bones, with the underlying cause remaining unknown. Granulocyte macrophage colony-stimulating factor(GM-CSF) is named for its produce granulocyte and macrophage precursors from bone marrow precursors, and it also serves as one of the regulatory factors in inflammatory and osteoclast formation. This study aimed to investigate changes in GM-CSF expression in frozen PDLSCs (fhPDLSCs) and evaluate the impact of GM-CSF on PDLSCs with respect to cellular activity and osteogenic ability. The role of GM-CSF in periodontal absorption was further speculated by comparing with IL-1β. The results revealed a significant increase in GM-CSF levels from fhPDLSCs compared to fresh cells, which exhibited an equivalent inflammatory stimulation effect as 1 ng/ml IL-1β. Cell viability also increased with increasing concentrations of GM-CSF; however, the GM-CSF from fhPDLSCs was not sufficient to significantly trigger osteoclastic factors. Considering its interaction with IL-1β and positive feedback mechanism, environments with high doses of GM-CSF derived from fhPDLSCs are more likely to activate osteoclastic responses.Therefore, for frozen tooth replantation, great attention should be paid to anti-inflammation and anti-infection.GM-CSF may serve as a potential therapeutic target for inhibiting periodontal resorption in delayed grafts.

Use of 3D printing models for donor tooth extraction in autotransplantation cases

OBJECTIVE

To clarify whether the 3D printing model has auxiliary functions in toto extraction of donor tooth in autotransplantation cases.

METHODS

Two hundred and sixty patients who would have operation of ATT were divided into two groups. In group 1, determination of the tooth extraction in toto was predicted only according to the clinical and imaging examination. In group 2, the prediction was performed according to the clinical and imaging examination as well as the 3D model of donor tooth pre-extraction. A prespctive clinical study was designed on intra-group comparison between the predicted and actual donor teeth situation when extraction in cases of ATT. The consistent rate for the predicted results and the actual results were compared with the two groups.

RESULTS

A remarkable difference was observed between the predicted results and the actual results of tooth positions and root numbers in group without model (p < 0,05). The consistency rate of the model group (94.62%) was significantly higher than that of non 3D model group (86.15%) (p = 0.034).

CONCLUSION

The 3D printing model for the donor tooth is helpful for dentists to predict the accuracy of toto extraction of donor teeth in autotransplantation cases.

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.

Evaluation of the 3D Technology in the Auto-transplantation: An Original Research

Introduction

Using three-dimensional printed duplicates of the donor teeth, three-dimensional auto-transplantation is a medical procedure that moves a tooth from one location inside a patient to another. The intraoperative practicability during 3D auto-transplantation of teeth was evaluated in the present study.

Material and Methods

A prospective multicenter clinical study was done among the subjects. "Preoperative cone-beam computed tomography imaging," "computer-assisted design (CAD)," and "computer-assisted manufacturing (CAM)" were used in all operations to make a 3D duplicate of the donor teeth. The clinical parameters that were evaluated were the time required for the fit, number of attempts to fit, and intra-operative experience.

Results

Canines, premolars, molars, and one extra tooth were all transplanted during the 200 auto-transplantation surgeries among 152 subjects. An initial satisfactory fit of the donor tooth and an extra-alveolar time of less than one minute were achieved in 80% of the surgeries. The extra-alveolar time exceeded 3 minutes in ten teeth. Difficulties that were faced were related to the imaging, patient cooperation, and the bone quality.

Conclusions

The application of the duplicate teeth by 3D printing of a donor tooth all through auto-transplantation techniques reduced the time the tooth stays extra-alveolar as well as the efforts at transplant fitting during implantation. This allowed for more challenging surgeries as well as a speedy and reliable therapy.

Modified single-step apexification and strengthening of thin dentinal walls with Biodentine

Apexification is a technique used to create a mineralized barrier in a root having an open apex or to continue the apical growth of a root that is still not fully developed in teeth with necrotic pulps. Biodentine is a versatile material which can help in achieving apical closure as well as reinforcement of thin dentinal walls, thus improving the overall prognosis and preserving the natural dentition. In the present case, the radiographic evaluation showed thinner dentinal walls and an open apex with periapical radiolucency in relation to the upper right central incisor. The large open root apex and thin dentin walls of immature permanent teeth render them challenging to treat with root canal therapy. This case report describes a modified single-step apexification procedure and strengthening of the dentinal walls of the root canal using Biodentine.

Guided Autotransplantation of an Immature Premolar to the Maxillary Incisor Region with Immediate Restoration of Esthetics: A Case Report

This case report describes the treatment of two maxillary central incisors following a traumatic injury with tooth #8 developing replacement resorption and #9 developing inflammatory root resorption. A 10-year-old girl presented complaining of pain in her maxillary central incisors. Upon clinical examination, teeth #8 and #9 were tender to percussion and palpation of the buccal soft tissues. Thermal and electrical pulpal sensitivity tests for teeth #8 and #9 were negative. An intraoral periapical radiograph revealed resorptive defects in tooth #8, which were filled with bone-like tissue, while tooth #9 had radiolucent resorptive defects along the root surface and a periapical radiolucency. A diagnosis of replacement resorption was made for tooth #8 and external inflammatory root resorption for tooth #9. Tooth #8 was treated with a multidisciplinary approach utilizing a guided template for premolar autotransplantation with an immediate veneer restoration, while tooth #9 was managed with root canal treatment using a tricalcium silicate cement to fill the canal. At the 1, 4, 8, 12, and 24-month follow-ups, the patient remained asymptomatic, and there was no radiographic evidence of root or periapical pathosis on either tooth. The root-end of the donor tooth transplanted to the #8 site continued to develop. This case report highlights successful interdisciplinary management of two forms of root resorption using modern treatment strategies that provided immediate function and esthetics to the maxillary central incisors in a young patient following trauma.

Validation of a Cox prognostic model for tooth autotransplantation

OBJECTIVES

This study aimed to validate our Cox proportional hazards prognostic model for autotransplantation of teeth with complete root formation using prognostic index (PI) and determine whether the prognosis can be predicted.

PATIENTS AND METHODS

The Protocol group, as a training data set for validation, consisted of 259 autotransplanted teeth to create a PI using the Cox model, as described previously. The Pre-protocol group, as the first validation data set, consisted of 95 autotransplanted teeth treated without a protocol. The Post-protocol group, as the second validation data set, consisted of 61 autotransplanted teeth obtained after the establishment of the prognostic model. Because four prognostic factors, including history of root canal treatment (yes), number of roots (multirooted), source of donor tooth (maxillary tooth), and duration of edentulism (≥2.5 months), were selected as a Cox prognostic model, 16 patterns of PI were constructed. First, the autotransplantated teeth in the Protocol group were divided into low- and high-risk groups respectively according to the median of PI as the cutoff value. The survival curves of low- and high-risk groups were calculated using the Kaplan-Meier method and tested using the log-rank test. Then, in the Pre- and Post-protocol groups, all transplanted teeth were divided into low-and high-risk teeth by the median of PI and the survival curves of low- and high- risk teeth were analyzed statistically in a similar manner.

RESULTS

The survival curves of the low- and high-risk groups diverged significantly in the Protocol and Post-protocol groups. In the Pre-protocol group, the curves of the low- and high-risk groups were separated, and the low-risk survival rate was improved.

CONCLUSIONS

Our Cox prognostic model for autotransplantation of teeth with complete root formation was useful in predicting the prognosis by external validation using PI.

Anterior tooth autotransplantation: a case series

Tooth autotransplantation is the technique of transplanting embedded, impacted or erupted teeth from one site into another in the same individual. It is relatively common for the anterior segment of the mouth to be affected by traumatic tooth injuries, impacted and/or congenitally missing permanent teeth. Autotransplantation of teeth into the anterior dental arch can provide unrivalled biological solutions when such issues arise in this critical aesthetic zone, particularly for adolescent patients. The combination of meticulous pre-surgical assessment, synergistic interdisciplinary collaboration and carefully performed anterior tooth autotransplantation has been demonstrated to achieve impressive outcomes, with respect to both transplant survival and clinical success. © 2023 Australian Dental Association.

Tooth autotransplantation: An umbrella review

Tooth autotransplantation is a versatile procedure with several clinical applications among patients across different age groups. The success of this procedure depends on multiple factors. Despite the wealth of studies available, no single primary study or systematic review is able to report on every factor affecting the outcomes of autotransplantation. The aims of this umbrella review were to evaluate treatment-related and patient-related outcomes of autotransplantation and to assess the pre-, peri- or post-operative factors that could affect these. An umbrella review was conducted according to the PRISMA statement. A literature search of five databases was performed up to 25 September 2022. Systematic Reviews (SR) with and without meta-analysis evaluating autotransplantation were included. Calibration among reviewers was carried out prior to study selection, data extraction and Risk of Bias (RoB) assessment. Study overlap was calculated using corrected covered area. Meta-meta-analysis (MMA) was performed for suitable SRs. The AMSTAR 2 critical appraisal tool was used to evaluate the quality of evidence. Seventeen SRs met the inclusion criteria. Only two SRs were suitable for conduct of MMA on autotransplantation of open apex teeth. The 5-year and 10-year survival rates were >95%. A narrative summary on factors that could affect autotransplantation outcomes and comparisons of autotransplantation to other treatment options were reported. Five SRs were rated as 'low quality' and 12 SRs were rated as 'critically low quality' in the AMSTAR 2 RoB assessment. In order to facilitate a more homogenous pool of data for subsequent meta-analysis, an Autotransplantation Outcome Index was also proposed to standardise the definition of outcomes. Autotransplantation of teeth with open apices have a high survival rate. Future studies should standardise the reporting of clinical and radiographic findings, as well as the definition of outcomes.

Accuracy of CAD-CAM surgically guided tooth autotransplantation using guided templates and custom-designed osteotomes in human cadaver mandibles

INTRODUCTION

A major challenge in dentistry is the replacement of teeth lost prematurely due to trauma, caries, or malformations, especially in growing patients. The aim of this study was to assess the accuracy of CAD-CAM surgically guided tooth autotransplantation in cryopreserved cadaver mandibles using guided templates and custom-designed osteotomes.

METHODS

Cryopreserved human cadaver heads were digitized and scanned using an intraoral optical scanner and a large-volume cone beam computed tomography (CBCT) device. First, virtual surgical planning was performed to create a 3D tooth replica, two surgical guides, and a custom-made osteotome for each single-rooted tooth autotransplantation procedure/case. Surgical sockets were created in the selected mandibles using guided tooling consisting of an initial guided osteotomy with implant burs and a final guided osteotomy using custom osteotomes. After tooth autotransplantation, second large-volume CBCT images of the five cadaver mandibles were obtained. The discrepancy in mm within the 3D space (apical and mesiodistal deviations) between the final position of the autotransplanted teeth and their digitally planned 3D initial position was calculated and analyzed statistically (P< .05).

RESULTS

All donor teeth were placed without incident within their newly created sockets in the real mandibles. The mean difference between the digitally planned root apex position and the final tooth position was 2.46±1.25mm. The mesiodistal deviation of the autotransplanted teeth was 1.63±0.96mm.

CONCLUSIONS

The autotransplantation of single-rooted teeth with custom-designed and 3D-printed surgical tooling provided promising results. The technique was able to create surgically prepared sockets that could accommodate transplanted teeth in mandibles.

Multimodal Imaging of Dental Pulp Healing Patterns following Tooth Autotransplantation And Regenerative Endodontic Treatment

INTRODUCTION

Understanding the healing process of dental pulp after tooth autotransplantation (TAT) and regenerative endodontic treatment (RET) of immature teeth is important both clinically and scientifically. This study aimed to characterize the pattern of dental pulp healing in human teeth that underwent TAT and RET using state-of-the-art imaging techniques.

MATERIALS AND METHODS

This study examined four human teeth, two premolars that underwent TAT and two central incisors that received RET. The premolars were extracted after one year (case 1) and two years (case 2) due to ankylosis, while the central incisors were extracted after three years (cases 3 and 4) for orthodontic reasons. Nanofocus x-ray computed tomography was used to image the samples before being processed for histological and immunohistochemical analysis. Laser scanning confocal second harmonic generation imaging (SHG) was used to examine the patterns of collagen deposition. A maturity-matched premolar was included as a negative control for the histological and SHG analysis.

RESULTS

Analysis of the four cases revealed different patterns of dental pulp healing. Similarities were observed in the progressive obliteration of the root canal space. However, a striking loss of typical pulpal architecture was observed in the TAT cases, while a pulp-like tissue was observed in one of the RET cases. Odontoblast-like cells were observed in cases 1 and 3.

CONCLUSION

This study provided insights into the patterns of dental pulp healing after TAT and RET. The SHG imaging sheds light on the patterns of collagen deposition during reparative dentin formation.

Guided Autotransplantation of Impacted Canines Using a CAD/CAM Surgical Template

Autotransplantation is a potential treatment alternative when orthodontic traction of an impacted tooth is difficult. In this article, we describe two cases of guided autotransplantation of an impacted canine using a computer-aided designed and manufactured surgical template. The impacted canine was segmented on preoperative cone-beam computed tomography images to ensure a sufficient periodontal ligament space and placement of the donor tooth with the least pressure on it. The canine was virtually transposed using a simulation program considering the adjacent teeth. The surgical template, which was connected to the occlusal stop on adjacent teeth, was designed and 3D-printed with polymer resin. The recipient site was prepared using the surgical template, followed by immediate transplantation of the surgically extracted canine into the socket. The transplanted donor tooth was positioned in planned infra-occlusion to prevent occlusal interference. It was then splinted with the adjacent teeth for initial stabilization. During follow-up, one transplanted tooth showed pulp canal obliteration and the other had suspected pulp necrosis; endodontic treatment was performed. One year after the procedure, the periradicular condition of both teeth was favorable.

Pulp revascularization after autotransplantation of the mandibular canines with partially resected roots. Report of five cases with follow-ups between 26 and 80 months

INTRODUCTION

Transmigrated (migrated through the midline) mandibular canines constitute a treatment challenge. Advanced transmigration can be successfully treated by autotransplantation. In developing canines, pulp revascularisation is typical after transplantation. On the contrary, the pulp of teeth with completed apex formation does not undergo revascularization. In this case, root canal treatment becomes compulsory and decreases the success of autotransplantation. The aim of this observational retrospective study was to evaluate whether partial resection of the root (performed during the autotransplantation of mature canines) would enable revascularization of the pulp after the surgery.

METHODS

Five transmigrated mandibular canines with complete apex formation before the surgery were evaluated. During the autotransplantation surgery, the resection of 2-4 mm of the root apex was performed to open the path for revascularisation of the pulp after surgery. The transplanted teeth were observed during healing after the surgery for the presence of pulp obliteration. Clinical and radiographic examinations were performed.

RESULTS

All treated canines survived the minimum observation period of two years (ranging from 26 to 80 months, mean: 55 months) without pulp healing complications. The survival was 100 percent, and the success was 80 percent. In one canine, the external cervical root resorption was diagnosed and treated one year after the surgery. At the final examination, transplanted canines presented radiographic features of pulp obliteration, normal mobility, and healthy periodontal tissues.

CONCLUSIONS

The surgical protocol proved to be successful in promoting revascularization to maintain pulp vitality, in all cases. The outcomes confirm that autotransplantation, combined with the resection of the root, constitutes as a valid treatment for mature ectopic canines.

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.

Tooth auto-transplantation: A bibliometric analysis of the top 100 most-cited articles

BACKGROUND/AIM

Tooth auto-transplantation has recently gained high clinical acceptance. The aim of this study was to identify the top 100 most-cited articles regarding tooth auto-transplantation, to analyse multiple citations and publication metrics and to outline the historical scientific advancements in this field.

MATERIALS AND METHODS

An advanced search of the Clarivate Analytics' Web of Science 'Core Collection' and Elsevier's Scopus databases utilising specific keywords related to tooth auto-transplantation between 1971 and 2021 was performed. The retrieved articles were ranked in descending order based on their Web of Science citation counts and further cross-matched with citation data from Scopus. The extracted data included citation counts, citation density, level of evidence, year of publication, contributing authors names and institutes, corresponding author's address, journal of publication, journal local citations index, cumulative growth index, keywords and keywords Plus. Data analysis was performed using descriptive statistics and graphical mapping.

RESULTS

A total of 1290 articles were retrieved. The top 100 most-cited articles received a total of 4899 (Web of Science) and 5250 (Scopus) citations. Among these, cohort studies (29%) and case series (18%) were the most common study designs. Scandinavian countries produced major contributions in defining the top 100 most-cited articles and ranked within the top 5 countries based on the number of publications and citations per year. The greatest contributing authors were Schwartz O (n = 12), Andreasen JO (n = 8) and Paulsen HU (n = 6), and they were affiliated with Copenhagen, Denmark. The top contributing journals were American Journal of Orthodontics and Dentofacial Orthopedics, International Journal of Oral and Maxillofacial Surgery, Oral Surgery Oral Medicine Oral Pathology Oral Radiology, European Journal of Orthodontics, Dental Traumatology and Journal of Oral and Maxillofacial Surgery.

CONCLUSION

This bibliometric analysis revealed a large geographical scientific interest and broad development in the field of tooth auto-transplantation spanning multiple dental disciplines.

Orthodontic management of a horizontally impacted maxillary incisor in an adolescent patient

Horizontal maxillary incisor impaction is not common, but it affects facial esthetics, phonetics, and the patient's self-esteem. Therefore, it is necessary to manage this problem as early as possible. This case report presents a patient with an unerupted maxillary left central incisor combined with anterior and left posterior crossbite, edge-to-edge overbite on the right and left anterior open bite, low smile line, and mild skeletal Class III discrepancy. The treatment consisted of 3 stages: (1) maxillary expansion and sufficient space creation for the impacted tooth; (2) surgical exposure by closed-eruption technique; and (3) induced eruption of impaction. The treatment outcome was highly favorable. Maxillary impaction erupted in the proper position with a normal clinical crown height and consonant gingival line with the adjacent teeth. Maxillary and mandibular teeth had normal and stable occlusion. The 3-year follow-up demonstrated an esthetically functional outcome after orthodontically induced tooth eruption. This treatment required a good treatment plan by the orthodontist to obtain satisfactory results.

Long-Term Survival Rate of Autogenous Tooth Transplantation: Up to 162 Months

Background and Objectives: The purpose of this study is to observe the usefulness of autogenous tooth transplantation by examining the cumulative survival rate according to the period of auto-transplanted teeth as pre-implant treatment. Materials and Methods: This study was conducted on 111 patients who visited Kyungpook National University Dental Hospital and underwent autogenous tooth transplantation between November 2008 and January 2021 (about 13 years). The cumulative survival rate of autogenous tooth transplantation according to the causes of extraction of the recipient tooth (caries, periapical lesion, crack, crown fracture, periodontitis) and condition of opposing teeth (natural teeth vs. fixed prosthesis). The cumulative survival rate of autogenous tooth transplantation according to the age (under 30 vs. over 30) was also investigated and it was examined whether there were any differences in each factor. Results: The average follow-up period was 12 months, followed by a maximum of 162 months. The 24-month cumulative survival rate of all auto-transplanted teeth was 91.7%, 83.1% at 60 months and the 162-month cumulative survival rate was 30.1%. There were no statistical differences between the causes of extraction of the recipient's teeth, differences in the condition of the opposing teeth, and differences under and over the age of 30. Conclusions: The survival rate of autogenous tooth transplantation appears to be influenced by the conditions of the donor tooth rather than the conditions of the recipient tooth. Although autogenous tooth transplantation cannot completely replace implant treatment, it is meaningful in that it can slightly delay or at least earn the time until implant placement is possible.

Dental autotransplantation as a alternative treatment for the loss of permanent anterior teeth in children

Introduction:

Autotransplantation is defined as the surgical movement or transposition of a tooth from its original site to a recipient alveolus, in the same patient. It has high success rates when performed within predefined parameters.

Objective:

This study aims to describe the advantages of a dental autotransplantation protocol based on a multidisciplinary approach and using cone beam computed tomography, computer-aided planning, and rapid prototyping of the donor tooth, enabling the preparation of a surgical guide and postoperative protective plate. This article discusses the indications and contraindications for autotransplantation, as well as the selection criteria for the tooth to be transplanted and the transoperative care essential for its success. The parameters for post-operative control are described, in addition to the variables of success and failure to be considered.

Conclusions:

When analyzing the treatment options available for children with anterior tooth loss and the psychosocial impact on these patients, autotransplantation is considered not only an alternative treatment, but the only viable option for their functional, aesthetic, and social reestablishment.

Present status and future directions: Root resorption

Root resorption is the loss of dental hard tissue because of odontoclastic action. In permanent teeth, it is undesirable and pathological in nature. Root resorption may occur on the inner aspect of the root canal (internal root resorption) or on the outer aspect of the root (external root resorption). Regardless of its location, root resorption is irreversible, and may result in discomfort for the patient, requires management and/or, in some cases, results in the premature loss of the affected tooth. Root resorption is often challenging to accurately diagnose and manage. The aim of this narrative review is to present the relevant literature on the aetiology, pathogenesis, diagnosis and management, as well as discuss the future directions of diagnosis and management of root resorption.

Knowledge, attitude, and practice of autotransplantation among the practicing pediatric dentists in Chennai - A questionnaire study

Background

Autotransplantation is a minor surgical procedure which involves transplantation of teeth within the same oral cavity. For children, autotransplantation may be considered as a provisional measure with good survival probability. It offers a viable biological approach for replacing the missing teeth and also for orthodontic treatments in children.

Aim

The aim of this study is to assess the knowledge, attitude, and practice of autotransplantation among pediatric dentists in Chennai, India.

Methods

An 18-item questionnaire was developed, piloted, and distributed among 100 practicing pediatric dentists in Chennai, India. Descriptive statistical analysis was done using Chi-square test.

Results

Seventy valid responses from the practicing pediatric dentists were obtained. Among them, 39.7% had an experience of 5-10 years, 47.1% practiced less than 5 years, and 13.2% had experience more than 10 years. Analysis of the responses showed that 76.5% of the pediatric dentists were aware of the procedure but have not observed autotransplantation being done. Among the respondents, 95.6% have not performed this technique and 40.6% of them were not sure of the prognosis. Atraumatic extraction of donor tooth was considered to be a major limitation in autotransplantation by 41.8% of the pediatric dentists. From the responses received, 95.6% were interested in gaining more information with majority opting for more hands on workshops on the technique of autotransplantation.

Conclusion

Though most of the respondents were aware of autotransplantation procedure, they have not practiced it due to inadequate training.

10-Year Follow-up of Previously-Traumatized Immature Permanent Incisors Sustaining Second and Third Traumatic Injuries After Revascularization Treatment: Case reports

The long-term prognosis of previously traumatized immature permanent teeth treated with guided endodontic repair is well documented, but little is known about how these teeth respond to further traumatic injury after treatment. This case report presents the 10-year clinical and radiographic findings of two patients with traumatized maxillary incisors who underwent guided endodontic repair treatment and sustained two further traumatic injuries. Three crown-fractured maxillary central incisors with pulp necrosis were treated with a protocol that used 2.5% NaOCl irrigation, 3-4 week medication with calcium hydroxide or ciprofloxacin-metronidazole paste, induction of apical bleeding, and coronal sealing with mineral trioxide aggregate. One tooth sustained subluxation and a crown fracture after 20 months and 7 years, respectively. Two other teeth had a luxation injury at 9 months and subluxation 6.5 years after the regenerative treatment. One subluxated and one luxated tooth remained free of symptoms for 10 years with radiographic evidence of progressive root canal calcification, while the other luxated incisor required root canal treatment after 7.5 years. Although teeth treated with the so-called "regenerative" endodontic techniques do not possess true pulp tissue, the reparative tissue may respond to traumatic injuries in a similar manner to teeth with normal pulps.

Does Root Development Status Affect the Outcome of Tooth Autotransplantation? A Systematic Review and Meta-Analysis

Background: Tooth autotransplantation is defined as the surgical repositioning of an autogenous tooth in another surgical site within the same individual. Aim: The aim of this research was to analyze the outcome of tooth transplantation using immature donor teeth compared with closed apex teeth and to compare differences between donor tooth positions on the arch. Methods: Electronic and manual literature searches were performed in different databases, including the National Library of Medicine (MEDLINE), EMBASE (OVID), Cochrane Central (CENTRAL), and the digital library of the Universitat Internacional de Catalunya (UIC University) from 1978 to March 2021. Studies were selected when they fulfilled the following criteria: only human prospective clinical studies, minimum sample size of 10 patients, minimum follow-up of 1 year, studies reporting or with at least deducible data on survival rates, immediate tooth autotransplantation with completed or incomplete root formation, and publications in the English language. A meta-analysis of random effects was developed to estimate the global effect measure of the survival rate, success rate, and root resorption involving the total sample, as well as open- and closed-apex groups. Results: Twenty-four articles were eligible for analysis. The Cohen’s kappa corresponding to this review was 0.87, and the risk assessment was considered low–moderate for the included studies. Overall survival and success rates were 95.9% and 89.4%, respectively, with a mean follow-up of 4 years and an overall mean age of 25.2 ± 12.3 years. Closed apex teeth showed a survival rate of 3.9% lower than that of open apex teeth. Higher complication rates were found for both inflammatory external root resorption and replacement root resorption in the closed-apex group, without reaching statistical significance. Conclusions: Tooth autotransplantation is a viable treatment alternative, regardless of the apical condition, with high survival and success rates after a mean follow-up of 4 years. Open-apex donor teeth could be considered the gold-standard option, showing lower complication rates when compared to closed-apex donor teeth. Future randomized controlled clinical studies are needed to examine the long-term prognosis of this technique.

Root Membrane Replantation as an Alternative Technique for the Socket Preservation

Background and Overview. Socket shield is a technique that allows the maintenance of tissue volumes. In the reported clinical case, the replantation of the buccal root fragment mistakenly extracted during a socket shield surgery is performed. We present a follow-up to 5 years with an unexpected healing.Case Description. An 88-year-old patient underwent an immediate loading implant placement associated with the replantation of the mistakenly extracted root fragment. The shaping of the fragment was performed extraorally, and the replantation was done so that the fragment protruded above the crest margin.Conclusions and Practical Implications. The 5-year follow-up shows an uneventful healing of the implant. At 48 months, postoperative CBCT exam reports images compatible with the regeneration of the bone over the portion of root that protruded over the margin. The outcome suggests clinical implications, as the opportunity to easily shape the fragment extraorally and replant sound portion of the root (not necessary the buccal) in buccal socket with bone defect.

Three-Dimensional (3D) Stereolithographic Tooth Replicas Accuracy Evaluation: In Vitro Pilot Study for Dental Auto-Transplant Surgical Procedures

After immediate tooth extraction or after alveolar socket healing, tooth transplants are increasingly used for functional restoration of edentulous maxillary areas. Recent studies have shown the periodontal ligament (PDL) viability and the tooth housing time in the adapted neo-alveolus as key factors for transplantation success. During surgical time, 3D stereolithographic replicas are used for fitting test procedures. In this paper, the accuracy of 3D dental replicas, compared with the corresponding natural teeth, is assessed in surgical transplantation. Lamb skulls were selected and submitted to Cone Beam Computer Tomography (CBCT). Scanning information, converted into Standard Digital Imaging and Communications in Medicine (DICOM) and Standard Triangulation Language (STL), was sent to the Volux X-ray Centre for 3D replica printing. After the tooth extractions, all lambs’ incisors were measured with a digital caliber and compared with the 3D replicas. Volume and dimensional error values were evaluated. All replicas showed macroscopically smaller volume (45.54%). Root replicas showed higher variations compared with the crown areas, with several unreplicated apical root areas. The cement–enamel junction tooth area was replicated quite faithfully, and the base area relative error showed 9.8% mean value. Even further studies with a larger number of replicas are needed. Data obtained confirmed high volumes of macroscopic discrepancies with several unreproduced apical root sites. The achieved accuracy (90.2%) confirmed that the 3D replicas cannot be used to reduce the surgical time during transplantation predictable procedures.

Influence of Static Navigation Technique on the Accuracy of Autotransplanted Teeth in Surgically Created Sockets

The aim of this study was to analyse and compare the position of single-rooted autotransplanted teeth using computer-aided SNT drilling and conventional freehand (FT) drilling, by comparing the planned and performed position at the coronal, apical and angular level. Materials and methods: Forty single-root upper teeth were selected and distributed into the following study groups: A. Autotransplanted tooth using the computer-aided static navigation technique (SNT) (n = 20) and B. Autotransplanted tooth using the conventional free-hand technique (FT) (n = 20). Afterwards, the teeth were embedded into two experimental models and 10 single-root upper teeth were randomly autotransplanted in each experimental model. The experimental models were submitted to a preoperative cone-beam computed tomography (CBCT) scan and a digital impression by a 3D intraoral scan, in addition to a postoperative CBCT scan, after the autotransplantation. Datasets from postoperative CBCT scans of the two study groups were uploaded to the 3D implant planning software, aligned with the autotransplantation planning, and the coronal, apical and angular deviations were measured. The results were analysed using Student’s t-test and Mann–Whitney non-parametric statistical analysis. Results: Coronal (p = 0.079) and angular (p = 0.208) statistical comparisons did not present statistically significant differences; however, statistically significant differences between the apical deviation of the SNT and FT study groups (p = 0.038) were also observed. Conclusions: The computer-aided static navigation technique does not provide higher accuracy in the positioning of single-root autotransplanted teeth compared to the conventional free-hand technique.

Impacted maxillary canine with curved apex: Three-dimensional guided protocol for autotransplantation

INTRODUCTION

Maxillary canines play a crucial role in dental and facial aspect, arch expansion, and efficient occlusion. When surgical exposure measures cannot be executed or the patient does not agree to take the treatment, autotransplantation should be considered. The aim of this case report was to describe a novel surgical technique using virtually planned three-dimensional(3D)-printed templates for guided apicoectomy and guided drilling of the recipient site for an autotransplantation of an impacted maxillary canine with a curved apex.

METHODS

A 42-year-old male complaining of pain and increased mobility in the maxillary left primary canine came to the clinic. Autotransplantation of the impacted canine was completed using altered methods from guided implant surgery to manufacture 3D-printed templates. Following a full-thickness mucoperiosteal flap elevation, the surgical template for the guided osteotomy and apicoectomy was inserted. This 3D-printed guided allowed the clinician to perform a quick and precise removal of the curved apex, providing an atraumatic extraction of the impacted canine throughout the cyst. Three further 3D surgical guides for implant burs and a 3D replica tooth were printed to modify the recipient socket. After the final position, the tooth was semi-rigid splinted to the adjacent teeth.

RESULTS

Follow-up at 2 years showed complete regeneration of the palatal defect and remodeling of the bone surrounding the maxillary canine.

CONCLUSIONS

Digitally planned procedures can facilitate the complex execution of an autotransplantation reducing the treatment chair-time and the morbidity for the patient as well as increasing the predictability of the result.

Tooth autotransplantation in a patient with rapidly progressing periodontitis aided by 3D printing

Patients with rapidly progressing periodontitis may require extractions of teeth with poor periodontal prognosis. Although replacement with a dental implant is a popular choice, teeth autotransplantation remains a viable option. Herein, we report a case of a 23-year-old patient with rapidly progressing periodontitis resulting in severe clinical attachment loss on the left maxillary first molar, which required extraction. The tooth was replaced by tooth autotransplantation of the unerupted immature left mandibular third molar, which was delivered carefully without compromising the periodontal ligament. Cone beam computed tomography and three-dimensional printing of the third molar donor tooth significantly aided the tooth autotransplantation procedure. Recovery was uneventful. At the 1-year follow-up, healthy periodontal parameters and radiographic features were noted, and the autotransplanted tooth remained vital. This case showed that tooth autotransplantation is a viable option for replacing tooth loss due to rapidly progressing periodontitis.

Mandibular premolar transplantation to replace missing maxillary anterior teeth: A multidisciplinary approach

One of the most challenging problems for orthodontists is that of multiple missing maxillary teeth in a growing patient. In many patients, a good treatment option is autotransplantation. This case report describes the multidisciplinary treatment of an 11-year-old girl with regional odontodysplasia affecting the maxillary right and left central incisors, and congenitally missing maxillary left lateral incisor and canine. Autotransplantation of the mandibular second premolars to the affected area was combined with orthodontic space closure, and the transplanted premolars were reshaped and restored with a resin composite to be in line with the left central and lateral incisors. After completion of the orthodontic treatment, gingivectomy was performed to obtain an even gingival contour and symmetrical gingival tissue. Space closure of the maxillary anterior teeth was achieved. Autotransplantation enabled the patient to retain her natural teeth rather than having a prosthesis or dental implant. The autotransplanted tooth allows for alveolar bone growth in synchrony with neighboring teeth and the formation of normal interdental papilla while adapting to functional stimuli and confers a high survival rate in the long term.

Aesthetic and functional restoration of the dental arch continuity in difficult cases of impacted teeth within the frontal segment

Impacted teeth are a fairly common defect with the incidence ranging from 2.9 to 13.7%. Evaluation of the efficacy and safety of various treatment modalities in patients with impacted teeth within the frontal segment of the maxilla. The retrospective evaluation covered treatment outcomes in 81 patients with impacted teeth within the aesthetic segment. The subjects were divided into 3 groups. Patients with the impacted tooth uncovered and orthodontically repositioned in the arch were assigned to group 1. Group 2 consisted of patients with the impacted tooth qualified for extraction and the gap augmented and restored with an implant. Group 3 included subjects, who underwent en-bloc autotransplantation of the impacted tooth. In 38 group 1 subjects 47 teeth were uncovered with a mean efficacy of 58.1% (96.3% and 70% in patients below 18 yoa and adults, respectively). The excellent aesthetic treatment outcome was obtained in 75% and good in 25% of patients. In group 2 twenty-six adult subjects were treated with 100% efficacy. In 65.4% of patients, augmentation with a bone block was performed and in the remaining 34.6%, implantation and augmentation with bone granulate. In 88.3% subjects a satisfying treatment outcome was obtained. In group 3 eighteen teeth in a block were grafted with the efficacy of 88.9%. Excellent aesthetics was obtained in 56.25% of cases and good in 31.25%. Orthodontic repositioning of the impacted teeth in the arch in adult patients bears the risk of failure. Surgical treatment modalities in impacted teeth are effective and provide high aesthetics of the treatment outcome improved by prior orthodontic treatment of the concomitant malocclusion and augmentation of the vertical bone atrophy before implantation.

Guided tooth autotransplantation in edentulous areas post-orthodontic treatment

OBJECTIVE

Tooth autotransplantation with a complete root formation to replace one or more lost teeth is indicated as a cost-effective alternative to implants. The aim of this case report was to describe a successfully guided autotransplantation of a maxillary third molar with fully formed roots into a surgically created socket after orthodontic space opening.

CLINICAL CONSIDERATIONS

A guided autotransplantation of the maxillary left third molar into the missing maxillary left first molar site was chosen. After virtually orientating donor tooth to confirm its optimum fit, it was deemed necessary to open 4 mm the mesiodistal space. Following the orthodontic movement, a 3-dimensional (3D)-guiding template and a milled surgical guide were manufactured to allow the donor tooth to be transplanted exactly in the planned position. The 2-year follow-up periapical radiograph showed a continuous periodontal space with no signs of apical periodontitis or root resorption.

CONCLUSIONS

Virtual planning and 3D-printed tooth replica combined with guided surgery can simplify the autotransplantation technique for both the clinician and the patient, particularly when the socket has been completely created during surgery.

CLINICAL SIGNIFICANCE

Virtual digital planning, which can accurately calculate the exact space to open orthodontically before an autotransplantation, could prove essential to enhancing the precision of 3D placement of the donor tooth in the recipient site.

Pre-autotransplantation alveolar process augmentation and premolar autotransplantation as a treatment method for single tooth replacement in adolescents

The treatment of young patients with missing teeth and an atrophied alveolar process after trauma or agenesis of a tooth can be challenging. The aim of this study was to evaluate autotransplantation of a premolar after pre-autotransplantation alveolar process augmentation (PAPA) as a treatment option for these patients. A retrospective cohort study was implemented to analyse the PAPA procedure and subsequent autotransplantation procedure. Alveolar process augmentation was performed using different types of autologous bone grafts. Subsequent autotransplantation of one or more premolars was performed approximately 4 months later. Nine patients with a mean age of 12 years were included. Twelve premolars were transplanted after a PAPA procedure: seven in the maxillary incisor region, four in the mandibular premolar region, and one in the mandibular incisor region. Initially all transplanted teeth functioned well. However, one mandibular premolar that was transplanted in the maxillary incisor region was lost because of resorption after 6 years of follow-up. The other 11 transplanted teeth functioned well. The mean follow-up was 6 years (range 3-13 years). The results showed that autotransplantation can be facilitated by PAPA with a high chance of success. It can therefore be a valuable addition to other existing treatment options.

Status of the alveolar bone after autotransplantation of developing premolars to the anterior maxilla assessed by CBCT measurements

Background/Aims

Autotransplantation of developing premolars is an established treatment to replace missing teeth in the anterior maxilla in growing patients with a reported success rate of over 90%. The normal shape of the alveolus is observed after transplantation, but data on the presence and amount of alveolar bone after healing has not been previously reported. The aim of this study was to look for potential differences in alveolar bone dimensions between sites where autotransplanted premolars replaced missing incisors and control sites of contralateral incisors.

Material/Methods

There were 11 patients aged between 10 and 12 years five months (mean age: 10 years and 7 months) who underwent autotransplantation of a premolar to replace a central incisor. Cone Beam Computed Tomography (CBCT) performed at least 1 year after transplantation served to evaluate bone at sites of autotransplanted premolars and controls (contralateral maxillary central incisor). The thickness of the labial bone, plus the height and width of the alveolar process were measured on scans and compared at transplant and control sites.

Results

Mean thicknesses of the labial bone at the transplant and control sites were 0.78 mm and 0.82 mm respectively. Mean alveolar bone height was 15.15 mm at the transplant sites and 15.12 mm at the control sites. The mean marginal thickness of the alveolus was 7.75 mm at the transplant sites and 7.98 mm at the control sites. Mean thicknesses of the alveolus for half of its vertical dimension at the transplant and control sites were 7.54 mm and 8.03 mm, respectively.

Conclusion

The mean values of bone thickness, width and height of the alveolar process at sites of transplanted premolars were comparable to the mean values for the control incisors. Successful autotransplantation of developing premolars to replace missing central incisors allowed preservation of alveolar bone in the anterior maxilla.