Indications for autotransplantation in cases of missing premolars

Long-term survival of 57 premolars consecutively transplanted to premolar sites

INTRODUCTION

The objective of this study was to report the long-term outcome of autotransplantation of premolars to other premolar recipient sites.

METHODS

The sample was limited to adolescents seeking orthodontic treatment, and all had 1 or 2 premolars transplanted to a recipient site in which a premolar was congenitally missing. The transplantations were performed between 1980 and 2008, comprising 29 premolars in 22 males and 28 premolars in 22 females. Systematic clinical and radiographic follow-up varied from 1 year to 36.8 years, with a mean observation time of 18.9 years and a median of 19.2 years. Of the 57 transplanted teeth, 52 were subjected to orthodontic forces.

RESULTS

A total of 9 of 57 teeth (15.8%) were lost during the observation period, and 8 of 9 lost teeth had been functional for at least 9 years posttransplantation. Of the 48 surviving transplants, 6 did not meet the criteria for success, giving an overall success rate of 73.7%. Complications were diagnosed within 5 years from the transplantation in 4 of 57 teeth (7.0%) and later in 11 of 57 (19.3%). The Kaplan-Meier survival curve shows that the complication-free proportion of transplants decreased at a constant rate over the observation time. The average survival time, taking censoring into account during follow-up of 36.8 years, was estimated as 28.5 years. The complications in the 15 teeth were classified into 4 categories: periapical lesions (6 teeth), inflammatory resorption (5 teeth), abrupt fracture (2 teeth), and ankylosis (2 teeth).

CONCLUSIONS

Overall, premolar transplants in all stages of root formation have high success and survival rates. Transplants with complications may survive temporarily and preserve critical arch space and alveolar bone. Transplants with normal healing may have latent weaknesses that can eventually affect long-term survival.

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.

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.

Evaluation of the accuracy of cone beam computed tomography (CBCT) generated tooth replicas with application in autotransplantation

OBJECTIVES

The primary aim of this study was to assess the linear and geometric accuracy of 3-dimensional (3D) printed tooth replicas when compared to the actual tooth. The secondary aims were to compare the accuracy of three different 3D printers and to evaluate dimensional changes of tooth replicas after sterilization.

METHODS

A sample of 16 teeth were selected from recruited patients. Segmentation was carried out to generate files from the patient's cone beam computed tomography (CBCT) data, Tooth replicas were then printed using three printers making use of Polyjet, laser stereolithography (SLA) and digital light processing (DLP) technology respectively. These replicas, along with the actual tooth, were scanned by an optical scanner. Replicas were sent for sterilization and scanned again. Paired superimposition of the scans was performed.

RESULTS

A mean length difference of 0.36 mm and mean geometric (root mean square [RMS]) difference of 0.56 mm was found. Qualitative analysis showed that the replicas were generally larger in size. Repeated ANOVA tests showed that the Polyjet printer had the highest accuracy (p<0.0001). After sterilization, there was an overall mean length difference of 0.10 mm and RMS deviation of 0.02 mm.

CONCLUSION

This study found that there was a significant difference in linear and geometric measurements of the tooth replicas when compared to the actual tooth. This study also provides evidence that the printer which made use of Polyjet technology was able to produce more accurate models than SLA or DLP printers. Printed tooth models demonstrated clinically insignificant changes after heat sterilization.

CLINICAL SIGNIFICANCE

3D printed tooth replicas derived from the patient's CBCT data may be used in autotransplantation to increase predictability of the procedure. In order for this novel digital approach to realize its potential, it is critical to address questions as to how accurate the various printing technologies are in fabricating replicas.

Interdisciplinary rehabilitation for mutilated dentition with mini-implants, autotransplants, and a dental implant

A patient with mutilated dentition was treated to an acceptable result with the help of mini-implants for anchorage, autotransplantation of 2 teeth, one dental implant, and multiple prostheses. The major problems for this mutilated dentition were multiple missing teeth, bite collapse with posterior crossbites, deepbite with a canted gummy smile, and severe skeletal discrepancy of maxillary protrusion and mandibular retrusion. Mini-implant anchorage was applied to retract and intrude the maxillary arch to reduce the protrusion and rotate the mandible counterclockwise to improve the chin projection. Two autotransplantations, one dental implant, and multiple prostheses were used to accomplish a satisfactory full mouth rehabilitation with an interdisciplinary approach, including orthodontics, periodontics, endodontics, prosthodontics, and implantology. The understanding of biological principles, improvement in surgical protocol makes it possible to preserve the periodontal ligament (PDL) cells with atraumatic extraction after loosening the donor with orthodontic force and reduce the extraoral time with the 3-dimensional print-out replica segmented from cone-beam computed tomography for trying fitness. Soft wire splinting to gain initial stabilization and root canal treatment to avoid endotoxin further reduce the risk of root resorption, loss of attachment, and ankylosis. Autotransplantation could be considered as a part of full mouth rehabilitation. Orthodontic space management is also an important procedure to confirm the site of dental implant installation in the interdisciplinary collaboration.

Sport and Dental Traumatology: Surgical Solutions and Prevention

Trauma is a worldwide cause of millions of deaths and severe injuries every year, all over the world. Despite the limited extension of the oral region compared to the whole body, dental and oral injuries account for a fairly high percentage of all body traumas. Among head and neck traumas, dental and facial injuries are highly correlated to sport activities, and their management can be a real challenge for practitioners of any specialty. In case of trauma directed to periodontal structures, restorative and endodontic solutions may not be sufficient to achieve a definitive and long-lasting treatment. This article aims to illustrate surgical options and appliances to prevent dental injuries that may be available to the clinicians treating dental trauma involving oral soft and hard tissues.

Autotransplantation of a mature mandibular third molar as alternative to dental implant placement: Case report

Dental autotransplantation is defined as the movement of one tooth from one position to another, within the same patient. Autotransplantation has predictable results; in fact, many studies describe a success rate of over 90%. This article describes a case report concerning the surgical management of this surgical technique. An 18-year-old patient comes for the treatment of her left first mandibular molar (3.6) involved in decay process. An accurate radiological analysis (periapical X-ray and orthopantomographic evaluation) showed an immature left mandibular third molar (3.8), suitable as donor tooth. The mandibular first molar was extracted in an atraumatic way. The intra-alveolar septum was modified with a piezoelectric device. The tooth was slightly depressed in the socket and remained in infra-occlusion. It was stabilized by sutures and a metallic splint. Then, the autotransplanted molar was fixed with a double splinting for 4 weeks. In conclusion, the autotransplantation was followed by endodontic treatment. After 36 months of follow-up, wisdom tooth showed an improvement in clinical features in agreement with radiological examination. The success of this case can be attributed to the atraumatic surgical technique and the immature stage of the transplanted element.

A conservative approach for an adult patient with a fractured tooth and crowding: Autotransplantation at the fracture site

Autotransplantation of a mature premolar in adults can be a treatment of choice for tooth replacement when combined with well-planned orthodontic treatment. This case report describes the successful treatment of a 39-year-old patient with severe crowding and a hopelessly fractured tooth on the maxillary left side. Maxillary dental crowding was relieved by extraction of a premolar on the right side, and this extracted tooth was autotransplanted to replace the fractured tooth. A mandibular incisor was extracted to correct anterior crossbite. The total treatment period was 20 months. The treatment results showed a good long-term prognosis after transplantation of a mature premolar with normal surrounding alveolar bone level for over 6 years of follow-up. Occlusion and periodontal health were excellent in the long term.

Autotransplantation of a surgically removed canine using a customised 3D-printed surgical template

Autotransplantation is a treatment option with high reported survival rates to replace failing teeth in the anterior maxilla. This treatment requires a multidisciplinary approach from orthodontists, paediatric dentists, restorative dentists, and oral and maxillofacial surgeons to achieve successful outcomes. Success is dependent on many factors including stage of root development, handling of the periodontal ligament, extra-alveolar time and splinting. This case report presents the novel use of digitally designed and three-dimensional (3D) printed surgical templates to aid intraoperatively and reduce the extra-alveolar time. A preoperative cone-beam computed tomography scan allowed digital planning and construction of surgical templates that replicated the exact root dimensions of impacted maxillary canines. These templates were subsequently 3D printed in resin, sterilised and utilised intraoperatively to aid socket preparation before the surgical autotransplantation.

Autotransplantation in combination with orthodontic treatment

INTRODUCTION

Autotransplantation is a surgical method in which a tooth is repositioned within the same patient. It can be described as a controlled reimplantation of an extracted tooth into a new, surgically prepared socket. The key to success of this treatment is the preservation and regeneration of the periodontal ligament. It is an underutilized technique which, if conducted with a multidisciplinary team, can be an ideal treatment option for patients with failing or missing teeth.

OBJECTIVES

The detailed clinical procedures, indications for this technique, and the factors affecting its success are discussed.

Root Elongation After Autotransplantation in 58 Transplanted Premolars: The Radiographic Width of the Apex as a Predictor

PURPOSE

Autotransplantation of premolars with incomplete root development is a reliable treatment option for tooth replacement. Nevertheless, little is known about root development after transplantation of teeth. The aim of this study was to evaluate preoperative root development stage and radiographic width of the apex as predictors for root elongation after autotransplantation.

MATERIALS AND METHODS

A retrospective cohort study was implemented and composed of patients who underwent autotransplantation of at least 1 premolar. Using panoramic radiographs (orthopantomograms), calibrated measurements were taken to record the root development stage of the donor tooth, width of the apex, and root length of the transplanted tooth.

RESULTS

Forty-five patients (58 transplants) were included. Mean follow-up time was 12 months (range, 4 to 26 months). Fifty-three transplanted teeth (91.4%) showed root elongation. Mean root elongation at end of follow-up was 1.9 mm (range, 0.0 to 4.3 mm). A wide-open apex before transplantation was significantly associated with root elongation after autotransplantation (P < .01). Root development stage (P = .82) did not show significant associations with root elongation.

CONCLUSIONS

A wide-open apex (>2.0 mm) is an important predictor of root elongation after autotransplantation of premolars. This might be a better predictor for root development than preoperative root development stage.

Survival rate of autotransplanted teeth after 5 years - A retrospective cohort study

BACKGROUND

Autotransplantation of teeth (TX) is a predictable treatment option, although this type of therapy is often overlooked compared to other types of restorations.

PURPOSE

As current literature contains few long-term studies concerning the outcome of autotransplanted immature molars, the aim was to evaluate results after a follow-up period of 5 years.

MATERIAL AND METHODS

This retrospective study enrolled all patients treated with immature autotransplanted molars after a follow-up period of 5 years. In order to ensure comparable results, survival rate was investigated as well as clinical and radiological parameters. Contralateral teeth (TC) were used as controls for further assessments and for ensuring comparable future results.

RESULTS

52 patients with 66 TX were examined. Mean age at the time of surgery was 19.64 years. Tooth survival rate after 5 years was 89.39%. The results for parameters such as PPD, BOP, mobility, dental caries, periapical pathologies and endodontic treatments showed no differences. In contrast, dental restorations (p < 0.001), occlusal contacts (p = 0.003) and sensitivity (p < 0.001) differed significantly between TX and TC.

CONCLUSIONS

The current findings clearly confirm that TX is an effective alternative treatment option to fixed prosthodontic restorations and dental implants, and provides for results equivalent to those with the patients' natural teeth.

A retrospective analysis of factors influencing the success of autotransplanted posterior teeth

Background

Survival and success rates of tooth transplantations even after long follow-up periods have been shown to be very high. Nevertheless, it is important to analyse factors potentially influencing these rates. The aim of this study was to assess the influence on success of potential factors.

Methods

The research was based on a retrospective analysis of clinical and radiological data from a sample of 59 subjects (75 transplanted teeth). The follow-up period varied from 0.44 to 12.28 years (mean 3.95 years). Success rates were calculated and depicted with Kaplan-Meier plots. Log-rank tests were used to analyse the effect of root development stage, apex width, the use of enamel matrix proteins or the surgeon on success of transplantations.

Results

Results for success of premolar transplantations were comparable with already published data, while molars performed worse than shown in other studies. The surgeon performing the transplantation (p = 0.001) and tooth type (p ≤ 0.001) were significantly associated with transplantation success. Use of enamel matrix proteins (p = 0.10), root development stage (p = 0.13), the recipient area (p = 0.48) and apex width (p = 0.59) were not significantly associated with success.

Conclusions

Molar transplantations were not as successful as premolar transplantations; however, success rates varied greatly depending on the surgeon’s experience. The use of enamel matrix proteins as well as root development stage, the recipient area and apex width did not show significant associations with success of tooth transplantations.

Canine autotransplantation: effect of extraction site preservation with a titanium prosthesis and a bioresorbable membrane

The permanent canine is the most frequently displaced or impacted tooth. The standard treatment for an impacted canine includes surgical exposure and orthodontic alignment. Autotransplantation is a treatment alternative for canines with complete root formation. The purpose of this article is to report a canine autotransplantation where the extraction site was preserved with a titanium prosthesis and a bioresorbable membrane. The autotransplanted canine had minimal root resorption and no ankylosis.

Transmigration of mandibular canines

The purpose of this paper is to present the first case of unusual reverse oblique (110 degrees to midsagittal plane) migration of mandibular right canine crossing the jaw midline and piercing the lower border of the mandible at the level of the opposite canine and also to report two more cases of transmigrated mandibular canine and one case of transmigrating mandibular canine. Mandibular canines are "cornerstone" of dental arch; their importance is manifested by their efficiency in masticatory function, stability of dental arch, and aid in maintaining natural facial expression. Early detection of this anomaly can help preserving these canines by orthodontic intervention or by surgical transplantation. This developmental anomaly is properly diagnosed by radiographic evaluation, which is primarily based on the panoramic radiograph. In patients with overretained deciduous canines or missing permanent canines, an intraoral radiograph should be supplemented with panoramic radiograph. This paper discusses the importance of early diagnosis of canine transmigration in treatment planning and reviews the various possible treatment options.

Orthodontic treatment after autotransplantation

Autotransplantation is an alternative method to replace a missing tooth. This study reports a 17-year-old man who had autotransplantation of the left upper third molar with the congenitally missing left lower second premolar. No signs of inflammation, root resorption, ankylosis, mobility, sensitivity, pocket problems, or pulp destructions were found after 2-year follow up. Autotransplantation can lead to shorter treatment time and an improved treatment result in certain cases. It also eliminates the need for implants or prosthetic therapy.

Success rate of autotransplanted teeth without stabilisation by splints: a long-term clinical and radiological follow-up

The purpose of this retrospective study was to assess the results after a follow-up of 10 years of autotransplantation of canines and third molars without the use of any apparatus for stabilisation. A total of 96 teeth were transplanted and 83 were successful (86%). The technique is easy, reliable, and effective.

Autotransplantation of premolars to premolar sites. A long-term follow-up study of 40 consecutive patients

This article describes the long-term outcome of 40 consecutive patients having transplanted premolars. The objective of this ongoing study is to investigate survival rate, pulp survival rate, periodontal condition, and root development of autotransplanted premolars in orthodontic patients. This report covers 17 years; 32 orthodontic patients had 40 premolars transplanted into contralateral or opposing jaw quadrants where a premolar was missing. The teeth were examined systematically with clinical and radiographic measures at 1, 2, 6, 12, and 60 months or more after autotransplantation. The observation time varied from 2 years 5 months to 22 years 3 months, with a mean of 10 years 4 months. Bonded.018-in edgewise appliances were used, subjecting 87.5% of the transplanted teeth to normal orthodontic forces. One tooth was removed because of root fracture during the observation period, and 2 more had complications possibly related to the transplantation. The remaining 37 teeth and their supporting structures were all healthy at the last examination--a 92.5% success rate. Transplants with closed apices received endodontic therapy, but, in those with open or half-open apices, a 66% pulp survival rate was observed. No teeth in the sample had signs of replacement resorption or developed periodontal attachment loss. Inflammatory resorption in 2 teeth was arrested after endodontic treatment. Root formation, when not complete, continued on transplanted teeth, giving normal root form and adequate root length for normal function. It is concluded that autotransplantation of premolars combined with orthodontic treatment should be the first treatment alternative in cases of missing premolars, when a suitable donor tooth is available.

Management of congenitally missing second premolars with orthodontics and single-tooth implants

This article describes the treatment of an adolescent girl who was congenitally missing all 4 second premolars and had a retained mandibular second primary molar. Various treatment alternatives are discussed, and the final treatment plan of space opening for 3 implants and space closure of the maxillary left second premolar site is presented.

Influence of orthodontic movement on root length of autotransplanted immature third molars

The aim of this study was to investigate the influence of orthodontic extrusion or derotation on final root length and root length increment in 75 autotransplanted immature third molars. Depending on the condition of the recipient site and the root morphology, transplants had to be placed in extreme rotated or infra-occluded position. Three to six months after transplantation, these transplants were derotated to a correct position in the dental arch (derotation group, n = 19) or extruded to the occlusal plane (extrusion group, n=18). Thirty-eight transplants with no orthodontic treatment need served as controls (control group). Transplants were followed clinically and radiologically for a mean period of 4.0 yr. No statistically significant differences were observed between the extrusion and the control groups or between the single-rooted transplants in the different groups. In contrast, multi-rooted transplants in the derotation group showed a statistically significantly shorter final root length than multi-rooted transplants in the extrusion and the control groups. However, as these differences may be considered to be of minor clinical importance (<1 mm), it can be concluded that the effect of orthodontic movement on root development of transplanted immature third molars is of only negligible clinical significance.

Nonprosthodontic management of alveolar clefts with 2 incisors missing on the cleft side: a report of 5 patients

A treatment combining autotransplantation of developing premolars and orthodontic space closure is described as an alternative to prosthodontics in the management of patients with alveolar clefts when 2 cleft-side incisors are missing. We report on 5 consecutive patients with unilateral clefts in whom 2 cleft-side incisors were congenitally missing, severely malformed, ectopically erupting, or lost because of trauma. In each instance, a mandibular premolar with a partly developed root was transplanted to the central incisor region (3 patients had previously undergone alveolar bone grafting). Root growth continued in all transplants. After an observation period of 2 years 6 months to 7 years 8 months, all transplanted teeth were present and fulfilled the established success criteria. The physiologic status of the transplanted premolars compared favorably with that of the central incisor on the noncleft side. The appearance of the reshaped transplants was found to match the noncleft incisor in 3 patients and deviated somewhat in 2. We concluded that an acceptable clinical outcome can be obtained by tooth transplantation combined with orthodontic space closure in patients with alveolar clefts and 2 missing cleft-side incisors.

Outcome of tooth transplantation: survival and success rates 17-41 years posttreatment

The literature contains no follow-up studies of transplanted teeth with mean observation times exceeding 10 years. This article describes long-term outcomes, including gingival and periodontal conditions, and the patients' attitudes about treatment and outcome. The material comprised all accessible patients in the files of the Department of Orthodontics, University of Oslo, Norway, on whom treatment had been performed at least 17 years ago (n = 28). Established clinical criteria were used to assess tooth mobility, plaque and gingival indexes, and probing pocket depth. Standardized radiography was used to evaluate the presence of pathology, pulp obliteration, and root length. Similar recordings were obtained from the in situ tooth contralateral to the initial position of the grafted tooth. Criteria for determining treatment success were established. All patients responded to questions about their treatment using visual analogue scales. The mean age at surgery was 11.5 years, and the mean observation period was 26.4 years (range, 17-41 years). Of the 33 teeth transplanted in the 28 patients, 3 teeth were lost after 9, 10, and 29 years, respectively. Therefore, the 30 teeth in the 25 patients we examined yielded a survival rate of 90%. The success rate was 79% because 2 transplants had ankylosed, and 2 others failed to fulfill the proposed criteria. The patients generally responded very favorably regarding their perception of the treatment. Their only hesitation was related to some discomfort during surgery. It was concluded that survival and success rates for teeth autotransplanted when the root is partly developed compare favorably in a long-term perspective with other treatment modalities for substituting missing teeth.

Autotransplantation of premolars to replace maxillary incisors: a comparison with natural incisors

The published literature contains no comprehensive studies that compare the outcome of premolar autotransplantation to the maxillary anterior region with natural incisors in the same patients. This article describes the gingival and periodontal conditions around premolars transplanted to the maxillary incisor region, subsequent to restoration. Forty-five premolars autotransplanted to the maxillary incisor region in 40 adolescent patients were evaluated after a mean observation period of 4.0 years. Mean age at surgery was 11.0 years. Established clinical criteria were used to assess tooth mobility, plaque and gingival indexes, probing pocket depth, and percussion. Recession and hyperplasia of interproximal gingival papillae were assessed according to a recently proposed index. Standardized radiography was used to evaluate presence of pathosis, pulp obliteration, root length, and crown-root ratios. Clinical variables for transplants did not differ from those of the natural incisors, except for increased mobility and more plaque in a few transplanted premolars. The interproximal gingival papillae adjacent to all transplanted teeth were normal or slightly hyperplastic. Radiographically, all transplants showed varying degrees of pulp obliteration, but no signs of pathosis. Crown-root ratios were similar for natural and transplanted teeth as were distances from cementoenamel junction to marginal bone. The overall status of the transplanted premolars and surrounding tissues indicated that this treatment modality may be recommended when maxillary incisors are missing in adolescents. In addition, tooth transplantation represents an inherent potential for bone induction and reestablishment of a normal alveolar process.

Autotransplantation of teeth: is there a role?

Autotransplantation of teeth, if carried out successfully, ensures that alveolar bone volume is maintained due to physiological stimulation of the periodontal ligament. Autotransplantation has been carried out for many years, but with varying success rates. As a result, it is seldom regarded as an appropriate treatment option for patients with missing teeth especially with the continued development of osseo-integrated implants. Since placement of osseo-integrated implants in growing alveolar bone is contra-indicated, transplantation of available teeth remains a suitable choice for replacing missing units in the young patient. The role of autotransplantation of teeth in several clinical situations, the clinical techniques involved and factors influencing success of the transplant are discussed. The aim of this paper is to underline the evidence based principles for successful autotransplantation and present the technique as a viable treatment option in present day orthodontic practice.

Autotransplantation of premolars. A retrospective study

The purpose of this clinical follow-up study was to evaluate the success rate of autotransplantation of human premolars. In the period between 1982 and 1994, 46 premolars in 31 patients were transplanted. A long-term success rate of 97.5% with a mean follow-up period of 3.5 years was achieved. It seems to be justified, therefore, in selected cases, to consider the possibility of autotransplantation as a good alternative to orthodontic or prosthetic treatment, including implant insertion, when closing a gap in the dental arch.

Premolar child-to-parent grafting within the framework of orthodontic serial extraction

While allografting of human teeth holds all the risks and problems of immunological reactions or host-versus-graft reactions encountered in any organ transplantation, root resorption and thus the loss of the grafted tooth may be delayed by several decades if the transfer is between close relatives and minimum histocompatibility is 50%. In 2 cases premolars with incomplete root growth, which had to be extracted because of considerable crowding, were transplanted from child to mother and child to father, respectively. The grafts healed without complications and after a retention time of several weeks the teeth were attached. Three years after transplantation the teeth show only minor signs of root resorption and are fully functional.

Autotransplantation of premolars and molars in patients with tooth aplasia

OBJECTIVES

The purpose of this study was to investigate retrospectively a group of patients who had undergone autotransplantation of teeth.

METHODS

The study group comprised 29 patients who had had a total of 31 teeth autotransplanted (22 premolars and nine molars). Seventeen premolars and one molar were moved from the upper to the lower jaw. The remaining premolars and molars were moved within the same quadrant. Twenty-three teeth were transplanted in cases of agenis, two in cases of ectopic eruption, and six after loss of the first molar. The observation period varied from 3 to 16 years (average 8 years). The patients were examined clinically, and radiographs were taken of the autotransplanted teeth. In addition, the patients were asked to complete a questionnaire.

RESULTS

By the end of the observation periods, four autotransplanted teeth had been extracted due to root fracture, caries, or external root resorption. In three of the patients who had lost their transplanted teeth and where no replacement had been inserted, the dentition had remained stable without tipping, rotations, or elongation. Most of the patients were happy with the autotransplantation and satisfied with the information that they had received in connection with the surgery.

CONCLUSION

Although not a frequent procedure, it was concluded that autotransplantation had a good prognosis after an (average) observation period of 8 years.

Orthodontic space closure without compensatory extractions in missing second lower premolars and Class I molar relationship

In a case of missing second lower premolars and class I molar relationship a good aesthetic and functional treatment result was achieved without compensatory extractions. The treatment method is described and the result discussed.

A clinical follow-up study of 278 autotransplanted teeth

This open study was undertaken to investigate the outcome of autotransplanted teeth over a 6-year period. The subjects were 296 patients who underwent autotransplantation in the 6-year period September 1986-August 1992 and outcome was measured by considering root formation, occlusion, endodontal and periodontal complications. 18 patients were excluded because of inadequate notes or radiographs (n = 3) or because they were lost to follow-up (n = 15). The groups were divided into open apex and closed apex, and duration of follow up was 6 months-5 years. Aplasia was the indication for operation in 158 (77 percent) of the open apex group but only 10 (14 percent) of the closed apex group, whereas caries and associated disease was the most common in the latter (n = 45, 61 percent compared with 20, 10 percent). There were 24 complete failures, 12 in each group (p <0.01). Only 7 teeth in total developed full roots, and 159 showed incomplete growth. In the open apex group 112 teeth were in occlusal contact and 4 were extracted for severe infraocclusion. In the closed apex group there were 10 cases of mild infraocclusion, none of which required treatment. There were 7 cases of pulp necrosis in the open apex group, 4 of which required extraction. Two teeth in the closed apex group were extracted for endodontic reasons. Only 1 tooth (in the closed apex group) had to be extracted for periodontal reasons. Autotransplantation is a reliable method with a good prognosis for donor teeth with both open and closed apexes. The technique is applicable whatever the aetiology of the agenesis, and is worthy of consideration should there be a suitable donor tooth.

Pulp and periodontal healing, root development and root resorption subsequent to transplantation and orthodontic rotation: a long-term study of autotransplanted premolars

One hundred and eighteen premolars transplanted at a stage with 3/4 to 4/4 root development with a wide open apical foramen were followed with standardized clinical and radiographic techniques for signs of pulpal and periodontal ligament healing and root development. Pulp healing, evaluated first by radiographic presence of pulp canal obliteration, appeared to be an earlier sign of pulp healing than the detection of pulp vitality with an electrometric test. Continued root growth of premolars was seen in some cases. Complete arrest of root development was usually followed by development of the missing root structure at the donor site, indicating a separation of the Hertwig's epithelial root sheath. Orthodontic rotation performed on 11 premolars induced slight surface resorption and a significant shortening of tooth length (mean 1.2 mm), compared with nontreated but transplanted control teeth. However, the extent of the apical root resorption is of minor clinical importance, and is equivalent to what has been found in previous investigations of orthodontic treatment of nontransplanted premolars. Late pulp necrosis occurred in 2 of the 11 treated cases 6 years after transplantation and 5 years after orthodontic rotation. To prevent late pulp necrosis, orthodontic rotation is recommended after periodontal healing and before total pulp canal obliteration has taken place, i.e., 3 to 9 months after transplantation.

Indications of autotransplantation of teeth in orthodontic problem cases

Autotransplantations of teeth have been widely used in orthodontics, mainly in cases of severe impactions, early loss of permanent teeth, or congenital aplasia. In specific clinical situations, indication of extractions or supernumerary teeth may provide donor teeth for transplantations avoiding prosthetic or implant therapy. Two cases are presented to illustrate the topic, and prognostic factors of autotransplantation are discussed.