Effect of denervation on healing after tooth replantation in the ferret

Studies have shown that the sensory nerves participate in inflammation and immune responses and possess trophic-facilitating wound healing in general. Tooth avulsion represents a pulpal and periodontal injury, and the mechanisms involved in the healing responses subsequent to replantation of teeth are still unclear. The objective of this study was to investigate the healing responses after denervation and replantation of teeth. Unilateral denervation was performed in 15 ferrets by axotomy of the inferior alveolar nerve, 5 days before extraction of the first lower premolars. Six weeks later the mandibles were excised and processed for histological evaluation. Immunohistochemistry was performed using antibodies against the sensory neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP), and measurements of root resorption and ankylosis were performed in four sections from each replanted tooth. After 6 weeks substantial reinnervation was observed in the jaws. Immunoreactivity in the pulp was observed in only two replanted teeth on the denervated side, compared with four on the innervated side. Total pulp necrosis appeared in 10 replanted teeth on the denervated side and in 5 on the innervated, indicating that sensory nerves promote survival of the pulp after replantation. SP-immunoreactive (IR) fibers were more frequently observed in the resorptive lacunae than CGRP-IR fibers. However, resorptive areas lacking IR fibers were frequently found along the root surface. Root resorption averaged 0.062 +/- 0.029 mm2 on the innervated side compared to 0.016 +/- 0.0043 mm2 on the denervated (P< 0.02). Ankylosis was observed in four of the replanted teeth on the innervated side (169.3 +/- 49.7 microm) and in six on the denervated side (332.56 +/- 193.2 microm) (P = 1). It is concluded that the sensory nerves promote root resorption after pulpoperiodontal injuries but have less influence on the osteoblastic activity expressed by ankylosis.     

Influence of root development on periodontal and pulpal healing after replantation of incisors in monkeys

The influence of root development on periodontal and pulpal healing after replantation was examined in 30 green vervet monkeys (cercopithecus aethiops) in which a total of 50 teeth were replanted. Maxillary central incisors with different stages of root development (immature, young mature and mature root formation) were replanted with untreated pulps or after root canal treatment with gutta percha and Kerr® sealer. The extra-alveolar period in all groups was 18 min. The animals were sacrificed 8 weeks after replantation and the teeth examined histologically. The following histologic parameters were registered for each tooth: surface resorption, inflammatory resorption, replacement resorption (ankylosis), downgrowth of pocket epithelium, periapical inflammatory changes and extent of vital pulp. Histologic analysis showed that the extent of vital pulp was significantly related to the stage of root development, being almost complete in teeth with immature roots and almost totally lacking in young mature and mature teeth. Surface resorption was found with the same frequency in the different root development groups while inflammatory resorption was slightly more frequent in young mature teeth than in mature teeth, a finding possibly related to a protective action of a thick cementum layer in the mature teeth. Replacement resorption was found with almost the same frequency in the different root development groups in non-endodontically treated teeth. As ankylosis is the most important factor determining the prognosis of replanted and autotrans-planted teeth, the present findings indicate that replantation and auto-transplantation of mature teeth could be of clinical use.     

Periodontal and pulpal healing of monkey incisors preserved in tissue culture before replantation.

The effect of delayed replantation and tissue culture as a prevention against root resorption was examined in green Vervet monkeys (Cercopithecus aethiops). Extracted incisors were kept in tissue culture medium (Eagle's medium) for 5--14 days before replantation. The extra-alveolar dry period before tissue culture ranged from to 0 to 60 min. Incisors not subjected to tissue culture served as controls. The animals were sacrificed 8 weeks after replantation. The following histologic parameters were registered for each tooth: surface resorption, inflammatory resorption, replacement resorption (ankylosis), downgrowth of pocket epithelium, and periapical inflammatory changes. The evaluation of the pulp included the extent, recorded in mm, of pulp survival. Histometric evaluation showed that teeth immediately placed in tissue culture medium for 5--14 days showed improved periodontal healing, exhibiting significantly less inflammatory resorption than control teeth immediately replanted. Also the extent of pulp survival was significantly increased in teeth replanted after tissue culture. Teeth bench-dried for 60 min and thereafter placed in tissue culture medium also showed a significant reduction in the amount of inflammatory resorption and increased amount of pulp survival compared with control teeth replanted after the 60-min dry extra-alveolar period. Replacement resorption (ankylosis) was found in all teeth in both groups.     

Replantation of 400 avulsed permanent incisors. 4. Factors related to periodontal ligament healing

Abstract 400 avulsed and replanted permanent teeth were examined for periodontal ligament (PDL) healing, using standardized radiographic and clinical examination procedures (i.e. percussion test and mobility test). The effect of various clinical factors was examined, such as age and sex of the patient, type of tooth replanted, presence of crown fracture or bone fracture, stage of root development (including apical diameter and length of the pulp), type and length of extra-alveolar storage, clinical contamination of the root surface, type of root surface cleansing procedure, type and length of splinting period and antibiotic therapy. Surface resorption was generally diagnosed after 12 months; while inflammatory resorption and replacement resorption (ankylosis) were usually observed after 1 month and 12 months respectively. Most resorptive processes were diagnosed within the first 2–3 years. However, although rarely, even after 5 and 10 years new resorptive processes could be diagnosed. A univariate statistical analysis of 272 teeth revealed 9 factors significantly related to PDL healing. A subsequent multivariate analysis revealed that the following 4 factors had the strongest impact upon PDL healing, in descending order of significance: Stage of root development; length of the dry extra-alveolar storage period; immediate replantation and length of the wet period (saliva or saline storage). Nonphysiological storage, such as homemade saline and sterilizing solutions (chloramine and alcohol) always led to root resorption. Storage in tap water for more than 20 minutes usually led to root resorption. The common denominator for all these factors related to PDL healing appears to be survival of the PDL cells along the root surface. Based on these findings, immediate replantation is recommended irrespective of stage of root development.     

Dynamics of dentoalveolar ankylosis and associated root resorption

Abstract The present experimental studies in monkeys were undertaken to study the initiation and progression of dentoalveolar ankylosis of replanted teeth and associated root resorption. Maxillary and mandibular lateral incisors were extracted and replanted after an extraoral period of 15 min or 1 h. Teeth with an extraoral period of 1 h were endodontically treated. Half the number of monkeys were given antibiotics at the time of replantation. The observation periods varied from 2 days to 40 weeks. Irrespective of the length of the extraoral period, initial root resorption and minor areas of ankylosis were found 1 week after replantation. The initial ankylosis was not preceded by root resorption. In teeth replanted after an extraoral period of 15 min the ankylotic area did not increase with increasing time after replantation. Instead the periodontal membrane was re-established, separating the root surface from the alveolar bone. In teeth replanted after an extraoral period of 1 h, the initial ankylotic area increased with increasing time after replantation. Eight weeks and more after replantation, most of the periodontal membrane was replaced by bone covered by osteoblasts and occasional osteoblasts that were in continuity with the endosteal cells outlining the marrow spaces of the alveolar bone. The cementum and dentin were then gradually resorbed with increasing time after replantation. Antibiotics given at the time of replantation reduced the initial inflammation in the periodontal membrane and the inflammatory root resorption after all observation periods and it also seemed to some extent to prevent bacteria from entering the necrotic pulp tissue. Based on the present results it is suggested that root resorption associated with dentoalveolar ankylosis is initiated by endosteal osteoblasts and is thus a hormonally regulated process. This is in contrast to inflammatory root resorption, which seems to be triggered by inflammatory cells.     

Dynamics of dentoalveolar ankylosis and associated root resorption

The present experimental studies in monkeys were undertaken to study the initiation and progression of dentoalveolar ankylosis of replanted teeth and associated root resorption. Maxillary and mandibular lateral incisors were extracted and replanted after an extraoral period of 15 min or 1 h. Teeth with an extraoral period of 1 h were endodontically treated. Half the number of monkeys were given antibiotics at the time of replantation. The observation periods varied from 2 days to 40 weeks. Irrespective of the length of the extraoral period, initial root resorption and minor areas of ankylosis were found 1 week after replantation. The initial ankylosis was not preceded by root resorption. In teeth replanted after an extraoral period of 15 min the ankylotic area did not increase with increasing time after replantation. Instead the periodontal membrane was re-established, separating the root surface from the alveolar bone. In teeth replanted after an extraoral period of 1 h, the initial ankylotic area increased with increasing time after replantation. Eight weeks and more after replantation, most of the periodontal membrane was replaced by bone covered by osteoblasts and occasional osteoblasts that were in continuity with the endosteal cells outlining the marrow spaces of the alveolar bone. The cementum and dentin were then gradually resorbed with increasing time after replantation. Antibiotics given at the time of replantation reduced the initial inflammation in the periodontal membrane and the inflammatory root resorption after all observation periods and it also seemed to some extent to prevent bacteria from entering the necrotic pulp tissue. Based on the present results it is suggested that root resorption associated with dentoalveolar ankylosis is initiated by endosteal osteoblasts and is thus a hormonally regulated process. This is in contrast to inflammatory root resorption, which seems to be triggered by inflammatory cells.     

Periodontal healing of exarticulated monkey teeth stored in milk or saliva

Abstract – Saliva has usually been recommended as a storage medium for exarticulated teeth. Recent tissue culture studies have, however, shown that milk has a more suitable osmolaliry than saliva and that milk is a bettter storage medium for human periodontal ligament cell. In the present investigation periodontal healing of replanted monkey teeth has been studied after storage of teeth in milk or saliva before replantation. There was much less root resorption, especially inflammatory resorption, after storage in milk thatn in saliva. Storage of teeth in milk for 3 h before replantation resulted in the same low frequence of root resorptions as was seen after immediate replantation. There was hardly any replacement resorption (ankylosis) seen in the replanted teeth.     

Long-term effects of local pretreatment with alendronate on healing of replanted rat teeth

Background and Objective:  Our previous study showed that topical alendronate, an inhibitor of bone resorption, reduces root resorption and ankylosis for 21 d after replantation of rat teeth. The aim of the present study was to evaluate the long-term inhibitory effects of topical alendronate in the replanted teeth.
Material and Methods:  The rat maxillary first molars were extracted, placed in saline containing 1 m m alendronate (alendronate group) or saline (saline group) for 5 min and then replanted. The maxillae were dissected at 60 and 120 d. Microcomputed tomography horizontal sections at three root levels were analyzed for root and bone resorption, ankylosis and pulp mineralization.
Results:  In the alendronate group at 60 and 120 d, the frequencies of resorption of roots and bone were lower than those in the saline group. The p values show statistical significances of lower frequencies in the alendronate group than in the saline group by chi-square test (see Table 1 ). Ankylosis and pulp mineralization occurred in the alendronate and saline groups. Bone marrow spaces were narrowed in conjunction with bone tissue expansion around the replanted teeth in the alendronate group.  

  Table 1.  Percentage of sites with ankylosis, root resorption, bone resorption and pulp mineralization for the alendronate and saline groups at 60 and 120 d after tooth replantation     

9.

Replantation of teeth and antibiotic treatment     

Lars Hammarström  Leif Blomlöf  Barry Feiglin  Lars Andersson  Sven Lindskog 《Dental traumatology》1986,2(2):51-57

Abstract Administration of antibiotics is usually recommended when a traumatically avulsed tooth is replanted, in order to prevent bacterial contamination. In the present study, permanent lateral incisors of monkeys were extracted, allowed to dry for 1 h and then replanted. Some teeth had their pulp chambers opened labially and left open for 3 wk after replantation. The monkeys were treated with antibiotics (i.m.) either at the lime of replantation or 3 wk after replantation. In some monkeys, antibiotics were placed in the pulpal cavity. Comparisons were made of the effect of endodontic treatment on periodontal healing and root resorption. The monkeys were killed 8 wk after replantation. It was found that after systemic antibiotic treatment at the time of replantation there was no inflammatory root resorption. Also, endodontic treatment at the time of replantation prevented inflammatory root resorption. When systemic antibiotic treatment was instituted 3 wk after (he replantation, there was no reduction of the inflammatory root resorption as compared with teeth without antibiotic treatment. Application of antibiotics in the pulp 3 wk after replantation almost completely eliminated the inflammatory resorption. In all the treatment groups where administration of antibiotics or endodontic treatment had prevented, reduced or eliminated inflammatory root resorption, 30–45% of the root surface area was ankylotic 8 wk after replantation.     

10.

Effect of stannous fluoride and tetracycline on repair after delayed replantation of root-planed teeth in dogs     

K A Selvig  K Bjorvatn  N Claffey 《Acta odontologica Scandinavica》1990,48(2):107-112

Mandibular incisors were extracted and allowed to dry in air for 45 min. They were then root-planed extensively, leaving a cervical collar and the apical region uninstrumented, to prevent direct contact between root surface and alveolar bone after replantation while, at the same time, enabling precise and stable reseating of the tooth. Control teeth were replanted either without further treatment or after treatment with citric acid for 3 min. Experimental teeth were treated before replantation with 1% SnF2 for 5 min, 1% tetracycline HCl for 5 min, or 1% SnF2 followed by 1% tetracycline. Histometric analysis of healing in the root-planed areas showed minimal amounts of inflammatory resorption and ankylosis after 21 days in experimental teeth as compared with the control teeth. A persisting inflammatory reaction in the periodontal ligament without root resorption was, however, frequently seen. The observations confirm that the frequency of adverse healing reactions after delayed replantation of teeth from which nonvital soft tissue remnants have been removed can be reduced by demineralizing the root surface and preventing mechanical trauma to the root surface in the postoperative period. Root surface treatment with SnF2 followed by tetracycline resulted in complete absence of inflammatory resorption and ankylosis in this short-term experiment.     

11.

Periodontal healing after intentional auto-alloplastic reimplantation of injured immature upper front teeth     

Pohl Y  Filippi A  Tekin U  Kirschner H 《Journal of clinical periodontology》2000,27(3):198-204

BACKGROUND/AIMS: Conventional endodontic treatment results in high complication quota when performed in immature teeth. Intentional reimplantation with extraoral insertion of an endodontic implant (auto-alloplastic reimplantation) is an alternative. METHOD: In a retrospective study, the healing of 40 teeth reimplanted intentionally according to this method in patients aged 7 to 15 years was evaluated. Clinical tests (palpation, percussion sound, periotest values) and radiographical examinations were used to determine the type of periodontal healing (inflammatory resorption/periodontitis apicalis; replacement resorption/ankylosis; normal healing). RESULTS: Mean lifetime of the replanted teeth was 59.2+/-42.5 months, estimated survival time on the basis of the Kaplan-Meier analysis was 99.5 months. 17 teeth (42.5%) were classified as failures, mostly due to inflammatory resorption or periodontitis apicalis. Further investigations demonstrated that success rate and retention period of intentionally replanted teeth depend on the preoperative condition of the pulp. Teeth with preoperative infection suffered frequently from inflammatory resorption or periodontitis apicalis after being replanted (14 of 28 teeth). Estimated survival time according to Kaplan-Meier was 75.5 months. In contrast, inflammations or progressive resorptions were not observed in teeth without preoperative infection of the pulp. All these 12 teeth showed normal periodontal healing and regular tooth mobility. In the absence of any pathology in clinical or radiological findings after an average functional period of 72.3 months, the prognosis can be presumed excellent. Estimated survival time of 148.3 months according to Kaplan-Meier differs significantly from survival time of teeth infected preoperatively. CONCLUSIONS: From the results of this investigation, it may be concluded that an infection of the pulp - due to delay of treatment or attempts at endodontic therapy - should be avoided before intentional replantation of immature front teeth with pulp necrosis. Periodontal healing of the autologous root is not impaired by the insertion of posts made of Al2O3-ceramics or titanium. The inserted posts do not ankylose. Orthodontic movement of auto-alloplastically replanted teeth is possible.     

12.

The effect of apicoectomy before replantation on periodontal and pulpal healing in teeth in monkeys     

J O Andreasen  O Schwartz  F M Andreasen 《International journal of oral surgery》1985,14(2):176-183

The effect of resection of the apical part of the root before replantation upon periodontal and pulpal healing was studied in 7 green Vervet monkeys (Cercopithecus aethiops) using teeth with incomplete and complete root formation. Maxillary central incisors, mandibular lateral incisors and first and second mandibular molars were used in this experiment. On one side, the tooth was extracted and replanted with an intact root while the contralateral tooth had 2 mm of the apex resected for the purpose of facilitating pulpal repair and eliminating resorption in the resorption-prone region of the root. The replanted teeth were examined histologically 8 weeks after replantation. The histometric analysis revealed no significant difference in periodontal healing between teeth with or without apical resection. With regard to pulpal healing, apical resection was found to lead to significantly less vital pulp tissue in teeth with immature root formation. A similar, but not significant difference was found for mature teeth. Based on these findings, it could not be recommended that apices be resected prior to replantation in order to improve pulpal repair.     

13.

Effect of stannous fluoride and tetracycline on periodontal repair after delayed tooth replantation in dogs.     

K A Selvig  K Bjorvatn  G C Bogle  U M Wikesj? 《Scandinavian journal of dental research》1992,100(4):200-203

Previous studies have indicated that inflammatory resorption and ankylosis, which are frequent sequela after delayed tooth replantation, can be greatly reduced by treating the root surface with 1% solutions of stannous fluoride and tetracycline. However, the SnF2 conditioning leaves a long-standing inflammatory reaction in the periodontal ligament. To examine whether a more dilute SnF2 solution would reduce postoperative inflammation without jeopardizing any beneficial effects, anterior teeth in three young adult beagles were extracted and allowed to air-dry for 45 min. They were then immersed in 0.1% SnF2 for 5 min, rinsed in saline, immersed in 1% doxycycline HCl for 5 min, rinsed, and replanted. Control teeth were air-dried and replanted without further treatment. Block biopsies were harvested after 4 wk of healing and processed for histometric analysis. In experimental teeth, 85% of the root surface area showed normal healing, compared to 33% in control teeth. Conversely, resorption and ankylosis were more frequent in controls than in experimental teeth. A persisting inflammatory reaction either adjacent to or at a distance from the root surface was seen in limited areas in both experimental and control teeth. Compared to preceding studies, the findings indicate that reducing the strength of the SnF2 solution from 1% to 0.1% may result in less persistent inflammation, at the cost, however, of less complete prevention of inflammatory resorption and ankylosis.     

14.

Clinical observations regarding the treatment of traumatically avulsed mature teeth. Part 1     

R J Matusow 《Oral surgery, oral medicine, and oral pathology》1985,60(1):94-99

A documented case involving the simultaneous avulsion of two maxillary incisors, intraorally and extraorally, was reported. Long-term observations following replantation treatment revealed several interesting clinical features: The prognosis of replanted teeth may be more favorable following intraoral avulsions. The intrusion phenomenon associated with replanted incisors appears to be directly related to replacement root resorption or ankylosis; occlusal forces may be a factor. Teeth extraorally avulsed for a few hours may still provide a useful function, albeit temporary, with replantation treatment. These teeth may not reveal clinical ankylosis or replacement resorption for periods of 1 to 2 years, or possibly longer, following replantation. Long-term studies can help evaluate replantation techniques.     

15.

Periodontal healing after replantation and autotransplantation of incisors in monkeys   总被引：2，自引：0，他引：2  

J O Andreasen 《International journal of oral surgery》1981,10(1):54-61

The effect of injury to the cemental or alveolar part of the periodontal ligament upon periodontal healing after replantation and autotransplantation of teeth was studied in green Vervet monkeys. Sixty-six maxillary central incisors were replanted or autotransplanted after extra-alveolar periods of 18 min. saline storage or 120 min. dry storage. The animals were sacrificed after 8 weeks and the teeth examined histometrically. Identical healing was found in the following experimental groups: replantation or autotransplantation after 18 min. and replantation with or without removal of periodontal ligament in the alveolus. A significant increase in replacement resorption (ankylosis) compared to the 18 min. replantation group was found in the following groups: replantation and autotransplantation after 120 min., replantation after removal of periodontal ligament on the root surface and autotransplantation after 120 min. to a socket where the tooth was extracted 18 min. earlier. Autotransplantation after 18 min. to a socket where a tooth had been extracted 120 min. earlier led to a significant increase in the amount of replacement resorption compared to transplantation to an 18 min. socket. Based on these findings, it is concluded that the presence of an intact and viable periodontal ligament on the root surface is the most important factor in assuring healing without root resorption. The length of the extra-alveolar period also seems to exert some influence upon the socket, enhancing the development of ankylosis.     

16.

Effect of lyophilized autologous plasma on periodontal healing of replanted teeth     

C E Nasjleti  R G Caffesse  W A Castelli  D E Lopatin  C J Kowalski 《Journal of periodontology》1986,57(9):568-578

The purpose of this histologic and autoradiographic study of replanted teeth was to evaluate the beneficial effect, if any, of lyophilized autologous plasma (LAP) application on periodontal healing and to re-examine rates of repair in different areas of the associated periodontium following replantation. Maxillary and mandibular incisors and premolars of three rhesus monkeys were used. Teeth were extracted with forceps and placed in sterile physiologic saline. After 5 minutes each tooth was returned to its socket and immobilized by interproximal acid-etch splints. Splints were removed after 1 week. Of the 48 replants performed, 24 (controls) were replanted as described. Of the 24 experimental teeth, during the 5 minute interval between tooth extraction and replantation, the root surface and the inner socket walls were bathed with 1 ml of the reconstituted LAP-saline solution (800 mg/ml). Replants and animal sacrifice were scheduled to provide observations at 1, 3, 7, 14, 28 and 45 days following replantation. One hour prior to sacrifice, each monkey received an intravenous injection of tritiated thymidine, 1 microCi/gm body weight. Tissue specimens were processed for evaluation following standard procedures. Eight replanted teeth were available for evaluation for each of the six time-points. Four teeth were treated with LAP and four without it. Histologically, tissue sections were examined for epithelial proliferation and attachment, periodontal fibers organization and maturation, inflammatory cell types, presence or absence of cementum resorption and dentoalveolar ankylosis and degree of vascularity of the tissues. For autoradiographic evaluation, the periodontium associated with the replanted tooth was divided into nine spatial cell compartments. In each compartment, labeled tissue cells, epithelial or connective, were counted and recorded. Differences between the control (untreated) replanted teeth and the LAP-treated teeth, at each time-point and within each compartment, were analyzed for significance using the paired t-test. The findings of this study indicate that LAP use enhanced healing by early replacement of the fibrin clot, increased connective tissue cell proliferation, reduction of the inflammatory response and inhibition of root cementum resorption. Periodontal healing and repair occurred more rapidly in the supracrestal or transseptal connective tissue region than within the periodontal membrane space.     

17.

Effect of stannous fluoride and tetracycline on periodontal repair after delayed tooth replantation in dogs     

Knut A. Selvig  Kjell Bjorvatn  Gary C. Bogle  Ulf M. E. Wikesjö 《European journal of oral sciences》1992,100(4):200-203

Previous studies have indicated that inflammatory resorption and ankylosis, which are frequent sequela after delayed tooth replantation, can be greatly reduced by treating the root surface with 1% solutions of stannous fluoride and tetracycline. However, the SnF₂ conditioning leaves a long-standing inflammatory reaction in the periodontal ligament. To examine whether a more dilute SnF₂ solution would reduce postoperative inflammation without jeopardizing any beneficial effects, anterior teeth in three young adult beagles were extracted and allowed to air-dry for 45 min. They were then immersed in 0.1% SnF₂ for 5 min, rinsed in saline, immersed in 1% doxycycline HC1 for 5 min, rinsed, and replanted. Control teeth were air-dried and replanted without further treatment. Block biopsies were harvested after 4 wk of healing and processed for histometric analysis. In experimental teeth, 85% of the root surface area showed normal healing, compared to 33% in control teeth. Conversely, resorption and ankylosis were more frequent in controls than in experimental teeth. A persisting inflammatory reaction either adjacent to or at a distance from the root surface was seen in limited areas in both experimental and control teeth. Compared to preceding studies, the findings indicate that reducing the strength of the SnF₂ solution from 1% to 0.1% may result in less persistent inflammation, at the cost, however, of less complete prevention of inflammatory resorption and ankylosis.     

18.

Extraoral endodontic treatment by retrograde insertion of posts: a long-term study on replanted and transplanted teeth   总被引：1，自引：0，他引：1  

Pohl Y  Filippi A  Kirschner H 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2003,95(3):355-363

OBJECTIVE: The aim of the study was to investigate the healing results of teeth replanted or transplanted in different indications and treated by extraoral root canal therapy. STUDY DESIGN: Extraoral root canal treatment was performed from a retrograde direction with posts made of ceramics or titanium. Preoperatively, the pulp status was classified as definitely infected (n = 47) or not infected/symptomless (n = 78), and the condition of the periodontal ligament (PDL) was classified as damaged (n = 50) or not damaged (n = 75) according to trauma type and extraoral storage. The healing after replantation or transplantation was diagnosed as functional, ankylosis, or infection depending on clinical and radiographic findings. RESULTS: In total, 125 teeth in 99 patients were replanted or transplanted. Mean observation period was 44.4 months. Teeth with a less damaged PDL in no case exhibited ankylosis/replacement resorption after a mean observation period of 53 months. Teeth without preoperative infection of the pulp in no case showed infection-related complications after a mean observation period of 30 months. Teeth classified as definitely infected before treatment had a high frequency of continuous periradicular bone and root resorption. CONCLUSIONS: The extraoral insertion of posts appeared to inflict no additional damage to the PDL that was clinically relevant. Infection-related complications were prevented. Teeth that were classified as definitely infected at the time of treatment had a low rate of healing and should undergo conventional root canal disinfection before this surgical procedure is applied.     

19.

Replantation of 45 avulsed permanent teeth: a 1-year follow-up study   总被引：1，自引：0，他引：1  

Vivianne Chappuis  Thomas von Arx 《Dental traumatology》2005,21(5):289-296

Abstract –  Thirty-four patients with 45 avulsed and replanted permanent teeth were followed for 1 year. All teeth were soaked in tetracycline before replantation. In addition, enamel matrix derivative was used in teeth with dry storage times exceeding 30 min. Splinting was carried out with a non-rigid titanium splint and was limited to 7–10 days. Within that period, root canal treatment was begun in all teeth with a closed apex, whereas teeth with an open apex and ideal post-traumatic storage were not instrumented. All patients were given tetracycline systematically for 10 days. The survival rate of replanted avulsed permanent teeth was 95.6% at the 1-year follow-up. In 82.2%, root canal treatment was performed. Pulp survival was never observed, but three teeth had pulp canal obliteration. Normal periodontal healing was observed in 57.7% of teeth; 42.3% of teeth showed external root resorption (28.9% replacement resorption, 6.7% infection-related resorption, 6.7% surface resorption). The occurrence of replacement resorption correlated with the period of extraoral dry storage. Compared with other clinical studies on avulsed and replanted teeth, the present study reports a higher percentage of periodontal healing. The favorable treatment outcome may be associated with a strict protocol to enforce endodontic treatment, the use of topical and systemic tetracycline, and the relatively high number of ideally stored teeth following avulsion. In contrast, the present study has a follow-up period limited to 1 year.     

20.

Delayed replantation after submucosal storage in order to prevent root resorption after replantation. An experimental study in monkeys     

J O Andreasen 《International journal of oral surgery》1980,9(5):394-403

The purpose of this study was to determine the root resorption pattern of teeth autotransplanted to a submucosal site and to determine whether root resorption after replantation could be prevented by delayed replantation of teeth after submucosal storage in order to regenerate damaged periodontal ligament. Permanent teeth were extracted in green Vervet monkeys. One group of teeth was transplanted to a submucosal site and examined histologically in situ. Another group of teeth was autotransplanted to submucosal sites, recovered and replanted either 2 or 6 weeks later. The animals were sacrificed 8 week after replantation and examined histometrically. The following histologic parameters were registered: surface resorption, inflammatory resorption, replacement resorption (ankylosis), periapical inflammatory changes and downgrowth of pocket epithelium. Teeth autotransplanted to submucosal sites developed surface and inflammatory resorption. In half of the cases where teeth were transplanted with a vital periodontal ligaments new formation of bone took place adjacent to the transplant. Delayed replantation after submucosal burial was not found to inhibit the development of ankylosis, but changed the resorption type from direct apposition of bone upon the root surface to apposition of bone after initial resorption.     

Replantation of teeth and antibiotic treatment

Abstract Administration of antibiotics is usually recommended when a traumatically avulsed tooth is replanted, in order to prevent bacterial contamination. In the present study, permanent lateral incisors of monkeys were extracted, allowed to dry for 1 h and then replanted. Some teeth had their pulp chambers opened labially and left open for 3 wk after replantation. The monkeys were treated with antibiotics (i.m.) either at the lime of replantation or 3 wk after replantation. In some monkeys, antibiotics were placed in the pulpal cavity. Comparisons were made of the effect of endodontic treatment on periodontal healing and root resorption. The monkeys were killed 8 wk after replantation. It was found that after systemic antibiotic treatment at the time of replantation there was no inflammatory root resorption. Also, endodontic treatment at the time of replantation prevented inflammatory root resorption. When systemic antibiotic treatment was instituted 3 wk after (he replantation, there was no reduction of the inflammatory root resorption as compared with teeth without antibiotic treatment. Application of antibiotics in the pulp 3 wk after replantation almost completely eliminated the inflammatory resorption. In all the treatment groups where administration of antibiotics or endodontic treatment had prevented, reduced or eliminated inflammatory root resorption, 30–45% of the root surface area was ankylotic 8 wk after replantation.     

Effect of stannous fluoride and tetracycline on repair after delayed replantation of root-planed teeth in dogs

Mandibular incisors were extracted and allowed to dry in air for 45 min. They were then root-planed extensively, leaving a cervical collar and the apical region uninstrumented, to prevent direct contact between root surface and alveolar bone after replantation while, at the same time, enabling precise and stable reseating of the tooth. Control teeth were replanted either without further treatment or after treatment with citric acid for 3 min. Experimental teeth were treated before replantation with 1% SnF2 for 5 min, 1% tetracycline HCl for 5 min, or 1% SnF2 followed by 1% tetracycline. Histometric analysis of healing in the root-planed areas showed minimal amounts of inflammatory resorption and ankylosis after 21 days in experimental teeth as compared with the control teeth. A persisting inflammatory reaction in the periodontal ligament without root resorption was, however, frequently seen. The observations confirm that the frequency of adverse healing reactions after delayed replantation of teeth from which nonvital soft tissue remnants have been removed can be reduced by demineralizing the root surface and preventing mechanical trauma to the root surface in the postoperative period. Root surface treatment with SnF2 followed by tetracycline resulted in complete absence of inflammatory resorption and ankylosis in this short-term experiment.     

Periodontal healing after intentional auto-alloplastic reimplantation of injured immature upper front teeth

BACKGROUND/AIMS: Conventional endodontic treatment results in high complication quota when performed in immature teeth. Intentional reimplantation with extraoral insertion of an endodontic implant (auto-alloplastic reimplantation) is an alternative. METHOD: In a retrospective study, the healing of 40 teeth reimplanted intentionally according to this method in patients aged 7 to 15 years was evaluated. Clinical tests (palpation, percussion sound, periotest values) and radiographical examinations were used to determine the type of periodontal healing (inflammatory resorption/periodontitis apicalis; replacement resorption/ankylosis; normal healing). RESULTS: Mean lifetime of the replanted teeth was 59.2+/-42.5 months, estimated survival time on the basis of the Kaplan-Meier analysis was 99.5 months. 17 teeth (42.5%) were classified as failures, mostly due to inflammatory resorption or periodontitis apicalis. Further investigations demonstrated that success rate and retention period of intentionally replanted teeth depend on the preoperative condition of the pulp. Teeth with preoperative infection suffered frequently from inflammatory resorption or periodontitis apicalis after being replanted (14 of 28 teeth). Estimated survival time according to Kaplan-Meier was 75.5 months. In contrast, inflammations or progressive resorptions were not observed in teeth without preoperative infection of the pulp. All these 12 teeth showed normal periodontal healing and regular tooth mobility. In the absence of any pathology in clinical or radiological findings after an average functional period of 72.3 months, the prognosis can be presumed excellent. Estimated survival time of 148.3 months according to Kaplan-Meier differs significantly from survival time of teeth infected preoperatively. CONCLUSIONS: From the results of this investigation, it may be concluded that an infection of the pulp - due to delay of treatment or attempts at endodontic therapy - should be avoided before intentional replantation of immature front teeth with pulp necrosis. Periodontal healing of the autologous root is not impaired by the insertion of posts made of Al2O3-ceramics or titanium. The inserted posts do not ankylose. Orthodontic movement of auto-alloplastically replanted teeth is possible.     

The effect of apicoectomy before replantation on periodontal and pulpal healing in teeth in monkeys

The effect of resection of the apical part of the root before replantation upon periodontal and pulpal healing was studied in 7 green Vervet monkeys (Cercopithecus aethiops) using teeth with incomplete and complete root formation. Maxillary central incisors, mandibular lateral incisors and first and second mandibular molars were used in this experiment. On one side, the tooth was extracted and replanted with an intact root while the contralateral tooth had 2 mm of the apex resected for the purpose of facilitating pulpal repair and eliminating resorption in the resorption-prone region of the root. The replanted teeth were examined histologically 8 weeks after replantation. The histometric analysis revealed no significant difference in periodontal healing between teeth with or without apical resection. With regard to pulpal healing, apical resection was found to lead to significantly less vital pulp tissue in teeth with immature root formation. A similar, but not significant difference was found for mature teeth. Based on these findings, it could not be recommended that apices be resected prior to replantation in order to improve pulpal repair.     

Effect of stannous fluoride and tetracycline on periodontal repair after delayed tooth replantation in dogs.

Previous studies have indicated that inflammatory resorption and ankylosis, which are frequent sequela after delayed tooth replantation, can be greatly reduced by treating the root surface with 1% solutions of stannous fluoride and tetracycline. However, the SnF2 conditioning leaves a long-standing inflammatory reaction in the periodontal ligament. To examine whether a more dilute SnF2 solution would reduce postoperative inflammation without jeopardizing any beneficial effects, anterior teeth in three young adult beagles were extracted and allowed to air-dry for 45 min. They were then immersed in 0.1% SnF2 for 5 min, rinsed in saline, immersed in 1% doxycycline HCl for 5 min, rinsed, and replanted. Control teeth were air-dried and replanted without further treatment. Block biopsies were harvested after 4 wk of healing and processed for histometric analysis. In experimental teeth, 85% of the root surface area showed normal healing, compared to 33% in control teeth. Conversely, resorption and ankylosis were more frequent in controls than in experimental teeth. A persisting inflammatory reaction either adjacent to or at a distance from the root surface was seen in limited areas in both experimental and control teeth. Compared to preceding studies, the findings indicate that reducing the strength of the SnF2 solution from 1% to 0.1% may result in less persistent inflammation, at the cost, however, of less complete prevention of inflammatory resorption and ankylosis.     

Clinical observations regarding the treatment of traumatically avulsed mature teeth. Part 1

A documented case involving the simultaneous avulsion of two maxillary incisors, intraorally and extraorally, was reported. Long-term observations following replantation treatment revealed several interesting clinical features: The prognosis of replanted teeth may be more favorable following intraoral avulsions. The intrusion phenomenon associated with replanted incisors appears to be directly related to replacement root resorption or ankylosis; occlusal forces may be a factor. Teeth extraorally avulsed for a few hours may still provide a useful function, albeit temporary, with replantation treatment. These teeth may not reveal clinical ankylosis or replacement resorption for periods of 1 to 2 years, or possibly longer, following replantation. Long-term studies can help evaluate replantation techniques.     

Periodontal healing after replantation and autotransplantation of incisors in monkeys

The effect of injury to the cemental or alveolar part of the periodontal ligament upon periodontal healing after replantation and autotransplantation of teeth was studied in green Vervet monkeys. Sixty-six maxillary central incisors were replanted or autotransplanted after extra-alveolar periods of 18 min. saline storage or 120 min. dry storage. The animals were sacrificed after 8 weeks and the teeth examined histometrically. Identical healing was found in the following experimental groups: replantation or autotransplantation after 18 min. and replantation with or without removal of periodontal ligament in the alveolus. A significant increase in replacement resorption (ankylosis) compared to the 18 min. replantation group was found in the following groups: replantation and autotransplantation after 120 min., replantation after removal of periodontal ligament on the root surface and autotransplantation after 120 min. to a socket where the tooth was extracted 18 min. earlier. Autotransplantation after 18 min. to a socket where a tooth had been extracted 120 min. earlier led to a significant increase in the amount of replacement resorption compared to transplantation to an 18 min. socket. Based on these findings, it is concluded that the presence of an intact and viable periodontal ligament on the root surface is the most important factor in assuring healing without root resorption. The length of the extra-alveolar period also seems to exert some influence upon the socket, enhancing the development of ankylosis.     

Effect of lyophilized autologous plasma on periodontal healing of replanted teeth

The purpose of this histologic and autoradiographic study of replanted teeth was to evaluate the beneficial effect, if any, of lyophilized autologous plasma (LAP) application on periodontal healing and to re-examine rates of repair in different areas of the associated periodontium following replantation. Maxillary and mandibular incisors and premolars of three rhesus monkeys were used. Teeth were extracted with forceps and placed in sterile physiologic saline. After 5 minutes each tooth was returned to its socket and immobilized by interproximal acid-etch splints. Splints were removed after 1 week. Of the 48 replants performed, 24 (controls) were replanted as described. Of the 24 experimental teeth, during the 5 minute interval between tooth extraction and replantation, the root surface and the inner socket walls were bathed with 1 ml of the reconstituted LAP-saline solution (800 mg/ml). Replants and animal sacrifice were scheduled to provide observations at 1, 3, 7, 14, 28 and 45 days following replantation. One hour prior to sacrifice, each monkey received an intravenous injection of tritiated thymidine, 1 microCi/gm body weight. Tissue specimens were processed for evaluation following standard procedures. Eight replanted teeth were available for evaluation for each of the six time-points. Four teeth were treated with LAP and four without it. Histologically, tissue sections were examined for epithelial proliferation and attachment, periodontal fibers organization and maturation, inflammatory cell types, presence or absence of cementum resorption and dentoalveolar ankylosis and degree of vascularity of the tissues. For autoradiographic evaluation, the periodontium associated with the replanted tooth was divided into nine spatial cell compartments. In each compartment, labeled tissue cells, epithelial or connective, were counted and recorded. Differences between the control (untreated) replanted teeth and the LAP-treated teeth, at each time-point and within each compartment, were analyzed for significance using the paired t-test. The findings of this study indicate that LAP use enhanced healing by early replacement of the fibrin clot, increased connective tissue cell proliferation, reduction of the inflammatory response and inhibition of root cementum resorption. Periodontal healing and repair occurred more rapidly in the supracrestal or transseptal connective tissue region than within the periodontal membrane space.     

Effect of stannous fluoride and tetracycline on periodontal repair after delayed tooth replantation in dogs

Previous studies have indicated that inflammatory resorption and ankylosis, which are frequent sequela after delayed tooth replantation, can be greatly reduced by treating the root surface with 1% solutions of stannous fluoride and tetracycline. However, the SnF₂ conditioning leaves a long-standing inflammatory reaction in the periodontal ligament. To examine whether a more dilute SnF₂ solution would reduce postoperative inflammation without jeopardizing any beneficial effects, anterior teeth in three young adult beagles were extracted and allowed to air-dry for 45 min. They were then immersed in 0.1% SnF₂ for 5 min, rinsed in saline, immersed in 1% doxycycline HC1 for 5 min, rinsed, and replanted. Control teeth were air-dried and replanted without further treatment. Block biopsies were harvested after 4 wk of healing and processed for histometric analysis. In experimental teeth, 85% of the root surface area showed normal healing, compared to 33% in control teeth. Conversely, resorption and ankylosis were more frequent in controls than in experimental teeth. A persisting inflammatory reaction either adjacent to or at a distance from the root surface was seen in limited areas in both experimental and control teeth. Compared to preceding studies, the findings indicate that reducing the strength of the SnF₂ solution from 1% to 0.1% may result in less persistent inflammation, at the cost, however, of less complete prevention of inflammatory resorption and ankylosis.     

Extraoral endodontic treatment by retrograde insertion of posts: a long-term study on replanted and transplanted teeth

OBJECTIVE: The aim of the study was to investigate the healing results of teeth replanted or transplanted in different indications and treated by extraoral root canal therapy. STUDY DESIGN: Extraoral root canal treatment was performed from a retrograde direction with posts made of ceramics or titanium. Preoperatively, the pulp status was classified as definitely infected (n = 47) or not infected/symptomless (n = 78), and the condition of the periodontal ligament (PDL) was classified as damaged (n = 50) or not damaged (n = 75) according to trauma type and extraoral storage. The healing after replantation or transplantation was diagnosed as functional, ankylosis, or infection depending on clinical and radiographic findings. RESULTS: In total, 125 teeth in 99 patients were replanted or transplanted. Mean observation period was 44.4 months. Teeth with a less damaged PDL in no case exhibited ankylosis/replacement resorption after a mean observation period of 53 months. Teeth without preoperative infection of the pulp in no case showed infection-related complications after a mean observation period of 30 months. Teeth classified as definitely infected before treatment had a high frequency of continuous periradicular bone and root resorption. CONCLUSIONS: The extraoral insertion of posts appeared to inflict no additional damage to the PDL that was clinically relevant. Infection-related complications were prevented. Teeth that were classified as definitely infected at the time of treatment had a low rate of healing and should undergo conventional root canal disinfection before this surgical procedure is applied.     

Replantation of 45 avulsed permanent teeth: a 1-year follow-up study

Abstract –  Thirty-four patients with 45 avulsed and replanted permanent teeth were followed for 1 year. All teeth were soaked in tetracycline before replantation. In addition, enamel matrix derivative was used in teeth with dry storage times exceeding 30 min. Splinting was carried out with a non-rigid titanium splint and was limited to 7–10 days. Within that period, root canal treatment was begun in all teeth with a closed apex, whereas teeth with an open apex and ideal post-traumatic storage were not instrumented. All patients were given tetracycline systematically for 10 days. The survival rate of replanted avulsed permanent teeth was 95.6% at the 1-year follow-up. In 82.2%, root canal treatment was performed. Pulp survival was never observed, but three teeth had pulp canal obliteration. Normal periodontal healing was observed in 57.7% of teeth; 42.3% of teeth showed external root resorption (28.9% replacement resorption, 6.7% infection-related resorption, 6.7% surface resorption). The occurrence of replacement resorption correlated with the period of extraoral dry storage. Compared with other clinical studies on avulsed and replanted teeth, the present study reports a higher percentage of periodontal healing. The favorable treatment outcome may be associated with a strict protocol to enforce endodontic treatment, the use of topical and systemic tetracycline, and the relatively high number of ideally stored teeth following avulsion. In contrast, the present study has a follow-up period limited to 1 year.     

Delayed replantation after submucosal storage in order to prevent root resorption after replantation. An experimental study in monkeys

The purpose of this study was to determine the root resorption pattern of teeth autotransplanted to a submucosal site and to determine whether root resorption after replantation could be prevented by delayed replantation of teeth after submucosal storage in order to regenerate damaged periodontal ligament. Permanent teeth were extracted in green Vervet monkeys. One group of teeth was transplanted to a submucosal site and examined histologically in situ. Another group of teeth was autotransplanted to submucosal sites, recovered and replanted either 2 or 6 weeks later. The animals were sacrificed 8 week after replantation and examined histometrically. The following histologic parameters were registered: surface resorption, inflammatory resorption, replacement resorption (ankylosis), periapical inflammatory changes and downgrowth of pocket epithelium. Teeth autotransplanted to submucosal sites developed surface and inflammatory resorption. In half of the cases where teeth were transplanted with a vital periodontal ligaments new formation of bone took place adjacent to the transplant. Delayed replantation after submucosal burial was not found to inhibit the development of ankylosis, but changed the resorption type from direct apposition of bone upon the root surface to apposition of bone after initial resorption.