SHORT ORAL PRESENTATIONS

	Title, author(s)
14.00–17.30	SHORT ORAL PRESENTATIONS
14.00-14.15	The critical apical diameter to obtain regeneration of pulp tissue after tooth transplantation, replantation or regenerative endodontic treatment Laureys Wim, Department of Orthodontics, University of Ghent, Belgium Introduction: Regeneration of pulp-like tissue in the pulp chamber after tooth transplantation, is only possible if the apical foramen is open. The success of regeneration decreases considerably if the foramen is smaller than 1mm, measured on radiographs. The aim was to study histologically the relation between the width of the apical foramen and regeneration of tissue in the pulp chamber after autotransplantation. Material and methods: Fifteen single-rooted mature teeth of three adult dogs were used. The teeth were extracted and apicoectomized, photographed and the width of the foramen was calculated. The foraminal width ranged from 0.24 to 1.09mm. All teeth were replanted in infra-occlusion. The observation period was 90 days post transplantation. Results: The teeth with the smallest apical diameter, showed vital tissue in at least one third of the pulp chamber. The most successful teeth showing vital tissue in the entire pulp chamber, had an apical diameter between 0.32mm and 0.65mm and 80 % of the experimental teeth with a diameter varying between 1.09 and 0.31mm, showed vital tissue in at least 1/3 of the pulp chamber, 90 days post transplantation. Conclusions: We can conclude, that the size of the apical foramen seems not to be the all-decisive factor for successful revascularization and ingrowth of new tissue after transplantation. A size smaller than 1mm does not prevent revascularization and ingrowth of vital tissue. In this study an apical foramen of 0.32 mm did not prevent ingrowth of new tissue.
14.15-14.30	Histological and imunnohistochemical pulpal tissue changes in replanted human premolars Vandevska-Radunovic Vaska, Department of Orthodontics, University of Oslo, Norway Objectives: The purpose of this study was to investigate time related dental tissue reactions to tooth replantation in mature and immature human premolars using histological and immunohistochemical methods. Material and methods: The material consisted of 83 permanent first premolars. Twenty-three teeth were extracted and fixed for histological preparation and 60 were extracted and immediately replanted (T0). Extraction of the replanted teeth took place 1,2,3,6,12 or 24 weeks later (T1). Paraffin-embedded teeth were sectioned at 5 μm, stained with hematoxylin-eosin and prepared for histological analysis. Eleven mature teeth from 1,2,3 and 12 week groups were prepared for immunohistochemistry and the levels of MMP-2, MMP-9, Annexin V, iNOS and BCL-2 in the pulp were analyzed. Results: Initial degeneration of the odontoblast layer and loss of normal architecture of the pulp was seen in both mature and immature teeth. The odontoblast layer reappeared from week 3 and was commonly accompanied by tertiary dentine formation in immature teeth between 6 and 12 weeks post-transplantation. This was followed by increase over time of MMP-9, Annexin V, iNOS and a decrease of BCL-2 and MMP-2. After 24 weeks, most immature teeth had pulps partly or completely obliterated. Conclusion: The dental pulp of immature teeth has potential for differentiation of new odontoblasts and production of tertiary dentine subsequent to replantation. The changes seen in immature teeth suggest that apoptosis is present and increases up to 12 weeks after replantation.
14.30-14.40	Clinical study on autotransplantation of teeth in patients aged over 60 years of age Abe Yuna 1,2, Matsuzawa Yusuke 1, Tei Kanchu 1 1 Department of Oral and Maxillofacial Surgery, Division of Oral Pathobiological Science, Graduate School of Dental Medicine, Hokkaido University 2 Department of Oral Surgery, Hokkaidoh Chuo Rosai Hospital Introduction: Tooth autotransplantation is a valuable treatment for recovering the occlusal function of missing teeth. Especially, in reports from countries other than Japan, the age of patients at the time of surgery is often adolescent or childhood. Generally, it is reported that the treatment outcomes in young patients is better than in older patients. Objective: The purpose of this study is to establish the characteristics of and clinical results for tooth autotransplantation in patients aged 60 years and older. Materials and methods: Patients were treated from July 1997 to March 2015. They were divided into an age group older than 60 years (over 60 group) and younger than 60 years (under 60 group), compared, and discussed. Results: The over 60 group was comprised of 38 patients and 44 teeth (male: 20 patients and 24 teeth; female: 18 patients and 20 teeth). The under 60 group was comprised of 553 patients and 739 teeth (male: 200 patients and 263 teeth; female: 353 patients and 476 teeth). Survival rate was 42/44 teeth (95.5%) in the over 60 group, and 678/739 teeth (91.7%) in the under 60 group. There were statistically significant differences in sex, classificati on of missing teeth of recipient site (intermediate tooth, last molar), pocket depth and tooth mobility after autotransplantation between the groups. Conclusions: Tooth transplantation for the over 60 group was able to avoid introducing dentures, and the clinical results were comparable to the under 60 group. It was concluded that, the tooth autotransplantation was useful.
14.40-14.50	Clinical protocol for tooth transplantation Deise Lima Cunha, Fausto Frizzera, Marco Antonio Masioli, Joao Batista Gagno Intra, Felipe de Assis R Carvalho, Associação Brasileira de Odontologia, Deise Lima Cunha, Brasil treatment is necessary to perform a working plan with a multidisciplinary team. These professionals are able to discuss and choose the best tooth to be transplanted, restored and the best way to close the donor area in order to provide a functional and esthetic result. Whenever the adequate space between the roots adjacent to the receptor area and the development of the donor tooth were obtained, a CBCT scan was done and a prototype was created. The artificial socket was prepared according to previously defined dimensions using sequential implant drills to obtain adequate blood pull. Prior to extraction of the transplant tooth, the prototype was used to verify if there was enough space in the site. This technique drastically reduces the time of transplanting the tooth from donor area to the final position in the receptor area. By doing so the damage on the periodontal ligament was reduced and the blood supply quickly returned which optimized and increased the capacity of the tissues for healing and regeneration. Aiming to evaluate root morphology and development over time, CBCT images were taken after 3 and 6 months after surgery and one year after the procedure during 5 years. The software ITK-SNAP 3.4 was used to build the desired 3D dental models of the transplanted teeth. MeshLab 1.3.3, allowed the surface to superimposition of the teeth models.
14.50-15.00	Orthodontic space closure and autotransplantation of first premolar to replace the traumatic loss of two maxillary incisors Harzer Winfried, Technical University of Dresden, Germany Introduction: The anterior maxilla is the most traumatized region during childhood and lead very frequent to tooth loss. Objective: The combination of orthodontic space closure and transplantation of a premolar from the mandible could be an alternative after traumatic loss of the lateral and central incisor in the maxilla. Subject and method: It is reported in a case from a girl nine years of age with orthodontic space closure and autotransplantation by a lower premolar for replacing the loss of two upper right incisors. Removing of the teeth and autotransplantation took place in one session within 15 minutes. After 8 days the fixation was removed and after 20 days the tooth re ceived a bracket within a fixed orthodontic appliance for moving in the right position. Radiographs for follow up were taken three, eight and 18 month after transplantation. Results: There was no any inflammatory reaction of the gingiva and complaining of the patient after transplantation. The tooth showed stability after six weeks with positive sensibility to temperature. In the X-rays dominated an increasing obliteration of the pulp and around the tooth the formation of alveolar bone and periodontal ligament. The DVT showed 20 weeks after transplantation the formation of the periodontal ligament on all sites. The crowns were prepared than for reshaping. Conclusion: A combination of both treatment modalities could be the functional and aesthetic optimum after temporary and permanent reshaping of the crowns.
15.00-15.10	Injured maxillary central incisors during childhood – impact on management in adulthood Krug Jiří, Centrum zubní implantologie, Praha, Czech Republic Introduction: Despite loss or serious damage of MCI during childhood, implant reconstruction must be accomplished in non-growing individual. However, alveolar crest is usually insufficient due to combination of dental trauma and atrophy. In advanced atrophy, the crest must be rebuild during one session and implant placement is postponed in 6 months (twostage approach). The aim of the study was to find out impact of injured maxillary central incisors (MCI) during childhood on management in adulthood. Material and methods: During 5 years (2011-2015), in total 72 patients underwent in our centre reconstruction of missing MCI by means of dental implants. In 33 cases (group A), two-stage approach was used. In 39 patients (group B), implants were placed together with bone augmentation during one session. Results: Nineteen (58%) patients in group A, reported dental trauma of MCI during childhood. In 8 individuals, tooth was removed immediately or soon after accident, in 11 patients, the tooth was saved, however, had to be removed in adulthood. In group B, none of the patients lost their MCI during childhood and only 8 of them (13%) had a dental trauma of the MCI during childhood, but the tooth was removed in adulthood. Conclusions: Dental trauma in childhood, frequently tend to advanced bone loss. In order to prevent that atrophy, young individuals with lost MCI should be always assessed for alternative approaches including autotransplantation or socket preservation.
15.10-15.25	Aesthetic outcome of autotransplanted premolars replacing maxillary incisors: A retrospective study De Pauw Guy, Tourné Stephane, Department of Orthodontics, University of Ghent, Belgium Purpose: The aim of this study was to evaluate the aesthetic outcome of autotransplanted premolars to the anterior maxilla. Materials and Methods: A cross-sectional study including 32 patients who have had an autotransplantation of a premolar to the maxillary incisor region, was conducted. Two types of restorations were chosen for the transplanted premolar: build-up with composite or porcelain laminate veneer. The mean observation time was 7 years (range: 1-23 years). The aesthetic outcome was rated using the Pink Esthetic Score (PES) and the White Esthetic Score (WES). Patients rated aesthetics by means of 100 mm visual analogue scales. Results: Patients responded very favorably regarding the treatment outcome. According to the PES and WES, 56% had acceptable aesthetics and 9% had a (almost) perfect outcome. Thirty-four percent were aesthetic failures (PES and/or WES< 6), mainly due to a low WES. Patients with a porcelain veneer scored significantly higher for the WES (p=0.026). Conclusions: Patients responded very favorably regarding the treatment outcome. The aesthetic outcome was disappointing in 34% of the cases. This result was mainly due to a low WES. Laminate veneers might be better to provide a more aesthetic result.
15.25-15.35	Critical aspects of reshaping transplanted premolars to anterior maxilla Jaszczak-Małkowska Magdalena, Warsaw, Poland Reshaping autotransplanted premolars to the morphology of missing upper incisor is a challenge for a prosthodontist. Tooth and smile aesthetics and preserving the tooth structure must be considered when planning and performing restorations at the transplanted premolars in an anterior maxilla. It’s critically important, when it comes to prosthodontic treatment of young patients in whom traditional restorative concepts cannot be applied. Contemporary advancements in adhesive procedures, preparation design and development in dental materials enable to preserve vital tooth structure and optimise aesthetics. The aim of this lecture is to describe the procedures and challenges of prosthodontic treatment in patients with transplanted premolars to replace missing central incisors. The concept of minimally invasive treatment will be highlighted using clinical examples.
16.00-16.10	Gain in Alveolar Bone Volume after Transplantation of a Developing Premolar in Case of Oligodontia: A Case Report Pallase Reet, Järve Martin, Clinic 32, Tallinn, Estonia Introduction: Treatment of a patient with oligodontia is challenging, especially in case of multiple teeth missing adjacently, causing lack of alveolar bone development. Objective: The objective of this report is to point out, that with autotransplantation of a developing tooth in case of deficient alveolar ridge an increase in bone volume can be achieved. Material and Methods: Developing lower right premolar was transplanted to centre position of adjacently missing upper left lateral incisor, canine and premolar in suboptimal position due to inadequate bone at recipient site. Measurements were taken from the cross-sectional views of CBCT scans 6 months before transplantation and 1 year and 4 months after transplantation. Alveolar height was measured from alveolar crest to nasal floor along vertical axis of teeth, alveolar width was measured at crestal quarter perpendicularly to the axis of teeth. Control measurements were taken at contralateral canine site. Results: Measurements at recipient site showed 1.50 mm increase in bone height and 3.09 mm increase in bone width after transplantation. Control measurements showed 1.13 mm increase in bone height and 1.51 decrease in width, which can be explained by the eruption of canine. Conclusions: Autotransplanted developing teeth show bone growth along their roots and allow increase in vertical dimension of alveolar ridge due to eruption, therefore transplantation of developing teeth in patients with deficient alveolar ridge is a viable treatment modality.
16.10-16.20	Selection criteria and post-surgical management for successful premolar transplantation to replace missing molars in adults Chooryung J. Chung, College of Dentistry, Yonsei University, Dep. Orthodontics, Gangnam Severance Dental Hospital, Korea
16.20-16.30	A Review of Eight Autotransplanted Teeth with Complete Root Formation Ishii Kazuhiro 1, Yoshizawa Michiko 2, Mayumi Yoshizawa 1, Funato Akiyoshi 3, Furusato Miyuki 1, Hayashida Takuya 1, Ishii Nobuko 1 1 Ishii Orthodontics, Komatsu, Japan 2 Department of Oral Reconstructive Surgery, Niigata University Medical and Dental Hospital, Niigata, Japan 3 Nagisa Dental Clinic, Kanazawa, Japan Introduction: We examined all the transplanted teeth with complete root formation at our office to get factors for more successful autotransplantation. Materials and Methods: Eight transplanted teeth in 7 patients were evaluated 1 year 7 months on an average after transplantation. Root resorption, ankylosis, mobility, pocket depth, and inflammation were investigated clinically and with radiographs. Results: All the teeth were survived nicely. Five teeth had normal physiologic tooth mobility (PTM) and excellent condition. Remaining 3 teeth had no tooth mobility. Concerning three of 5 teeth with normal PTM, each was transplanted into a recipient cite where upper or lower previous permanent molar had been extracted about one month before because of dental caries or untreatable periapical lesion. One of the remaining two teeth with PTM was placed into lower 2nd premolar congenital missing site immediately after extraction of remaining 2nd primary molar with solid roots. The last one with PMT was positioned into lower 2nd premolar missing site after bridge pontic was removed. Regarding the three teeth with no mobility, one showed cervical root resorption. This was transplanted into congenital missing upper 2nd molar place. The other two did not show any root resorption radiographically. One of these two was placed into congenital missing site of upper 2nd premolar with no primary tooth, and another one into upper 2nd molar site which had been missing for a long time. All the three teeth with no mobility did not show any clinical problem as donor teeth before transplantation. Plus all the three transplantation were done by a skillful senior surgeon (M. Y.).
16.30-16.45	Survival- and success rates of 100 consecutive autotransplanted incomplete developed premolars during a 3 years period at a single Norwegian university center Herlofson BB, Johnsen PG, Kløv M, Tingberg M, Bjørnland T. Department of Oral Surgery and Oral Medicine, Faculty of Dentistry, University of Oslo, Norway Introduction: Autotransplantation of immature premolars in young children with dental aplasia or teeth lost due to trauma is a good treatment option. The survival- and success rates vary greatly between different studies. Many factors need to be considered before surgery, including the patient`s age, the root development and accessibility of donor tooth, the condition of recipient site and the experience of the surgeon. Aim: The aim of this master student study was to evaluate the survival- and success rates in a cohort of autotransplanted teeth in young children at the Department of Oral Surgery and Oral Medicine, Faculty of Dentistry, University of Oslo, Norway during a 3 years period. Material and methods: All autotransplanted teeth performed during September 2010 to December 2013 with a minimum of 6 months follow-up time were included in the evaluation. All study data, clinical and radiographical, are based on the patients` dental journals, only. No patients were clinically examined. Results: The study showed a survival and success rates of 94% and 82%, respectively, of teeth transplanted to premolar- or frontal regions. 100 teeth were transplanted in 93 patients during the study period with a follow-up time from 6 to 60 months. 77 of the donor teeth (premolars) were transplanted to premolar areas, 21 (premolars) to upper incisor site, one (premolar) to molar area and one incisor to frontal area. Six out of 18 teeth described with different type of complications had to be removed during the followup time mostly due to ankylosis. The remaining 12 teeth were described to have uncertain prognoses. Conclusion: The study showed survival- and success rates in the same positive range as other studies with autotransplantation of immature premolars in young children with agenesis or teeth lost due to trauma.
16.45-17.00	Premolar transplantation and late complications Jónsson Teitur, Jónsdóttir Hafdís Faculty of Odontology, University of Iceland, Reykjavík, Iceland The study describes long term findings of premolar transplants in a consecutive sample since 1980. The first results were published in 2004 in a paper by Jonsson and Sigurdsson, describing 40 teeth with a mean observation time of ten years. The second report is based on new radiographs, photographs and clinical examinations of the extended sample, updating records of premolars transplanted in the years 1980 to 2008. The focus is on late complications, but other variables include survival and success rates of the transplants, periodontal health, pulp vitality and continuing root growth. Examples of late complications, discovered more than 15 years after the operations, include periapical lesions, fractured roots, fractured crowns, lateral resorptions and caries. A patient survey was conducted in 2012, confirming a high level of patient satisfaction. The participation in the survey was 91%, suggesting that circumstances in Iceland may present a unique opportunity for a long term observation of a uniform, consecutive sample with minimal dropout.
17.00-17.20	15 years with autotransplants – past experience (happiness as well as some disillusions) and current view Marek I, Starosta M, Novosad M. Breclav, Olomouc, Czech Republic Autotransplants have been known since ancient times. However, the most significant advancement in this method started in 1970s, when the principles of surgical procedures and the subsequent orthodontic treatment were determined exactly. The most common donor is second premolar, or alternatively maxillary third molar. When assessing the success rate of the autotransplant, the survival rate and the success rate are used; according to studies, the survival rate is 90–100% and success rate is 70-90%. Autotransplants with complications (e.g. inflammatory root resorption or ankylosis) are not considered successful. Thus the autotransplant as a biological implant reaches higher success rate than a standard implant. However, failures, such as ankylosis in growing up patients, bring about substantial complications, which leads to disillusionment. The authors analyse possible reasons for autotransplant failures and other complications within surgical procedures, or orthodontic therapy or the follow-up endodontic treatment. New possible changes in the protocol are suggested here (e.g. using tooth replica made by 3D printers), which would lead to higher success rate. In another part of the report, the authors deal with autotransplants of fully developed teeth. The importance of perfect root canal filling is stressed here and the authors present their protocol here. The case report is supplemented with atypical indications of autotransplants.
17.20-17.30	Autotransplantation and cryopreservation of immature teeth Temmerman Liesbeth, De Pauw Guy. Department of Orthodontics, Ghent University Hospital, Belgium Sometimes the optimal timing for autotransplantation is not always present, limiting the number of indications. For example, when at the appropriate time of transplantation (root formation) the recipient site is too small and orthodontic treatment is required to gain space in the dental arch. Temporarily storing the teeth at ultra-low temperatures (cryopreservation) at their ideal developmental stage can offer a solution to this problem. Another example is a clinical situation where extractions of premolars for orthodontic purposes are indicated in a patient with a traumatised incisor with an uncertain prognosis. The teeth can be stored until replacement of the traumatised tooth is necessary. The aim of cryopreservation of living tissues is the “controlled reversibility of the cessation of all biologic functions”. However, the ultra-low temperatures (up till -196°C) can give rise to cellular injury. This can be limited by the use of cryoprotective agents in combination with a slow freezing rate. Several in vitro and animal studies in rats have proven the efficacy of the cryopreservation procedure. The results of these studies are very promising and ask for further investigation. The influence of cryopreservation on the pulpal tissue and on periodontal ligament cells in vitro will be discussed.