Effect of immediate calcium hydroxide treatment and permanent root-filling on periodontal healing in contaminated replanted teeth

Abstract – The effect of immediate permanent root-filling and immediate intracanal calcium hydroxide treatment on experimentally contaminated and necrotized periodontal membranes (PDM) in avulsed and subsequently replanted monkey teeth was studied. Almost the entire root surface in the non-endodontically treated control teeth were covered with inflammatory resorp-tion, A significant shift towards ankylosis not associated with root resorption (> 80% of the total root surface area) was noted following calcium hydroxide treatment. About two thirds of the root surfaces from the teeth with permanent root fillings showed surface resorptions or ankylosis preceded by root resorption. The root surface area which would have been covered by inffammatory resorption, unless endodontic treatment had been implemented, were instead predominantly covered by either surface resorption (permanent root filling) or ankylosis (calcium hydroxide treatment), Ankylosis compared with surface resorption may in the long term lead to progressive loss of root substance due to replacement resorption. It was concluded that calcium hydroxide may be an excellent initial intracanal treatment in teeth with healthy PDM, but care should be taken not to risk unnecessary development of ankylosis by prolonged treatment of teeth with compromised PDM.     

Progression of root resorption following replantation of human teeth after extended extraoral storage

Abstract Avulsed human permanent teeth subjected to a minimum of 1 h dry extraoral storage before replantation were followed radiographically for an average of 4.8 years. The depth of root resorption cavities was assessed using a radiographic index, and the rate of root resorption was defined as the index change over time. The frequency of inflammatory and replacement resorption was determined at each observation time. Replacement resorption increased in frequency with time in all patients. In teeth endodontically treated within 3 weeks of replantation, minimal inflammatory resorption was found regardless of the age of the patients. In teeth where endodontic treatment was performed more than 3 weeks after replantation, the frequency of inflammatory resorption was significantly higher in young patients but not in older patients, up to more than 3 years after replantation. The rate of root resorption was found to be related to age. In patients 8–16 years old at the time of avulsion the rate of root resorption was significantly higher compared with patients 17–39 years old. Age had a higher impact on the rate of root resorption compared with the delay in endodontic treatment after replantation. It was concluded that a tooth replanted with a necrotic periodontal membrane will become ankylosed and resorbed within 3–7 years in young patients, whereas a tooth replanted under similar conditions in older patients may remain in function for a considerably longer time.     

Endodontic pathogens: propagation of infection through patent dentinal tubules in traumatized monkey teeth

Abstract Periapical pathology indicating endodontic infection, when present in marginal periodontitis-affected teeth, has recently been shown to be an aggravating factor in progression of marginal destruction. This has been associated with patency of dentinal tubules in the tooth cervix, an area normally devoid of cementum following periodontal therapy. These studies are, however hampered by that only circumstantial evidence such as presence of periapical destruction have been applied as criteria of endodontic infection. The purpose of the present investigation was to study to what extent a predefined selection of endodontic pathogens inoculated in the root canal can influence periodontal pathology and healing in areas of the root covered by or devoid of cementum, using root resorption as a histomorphometric marker. Exposed dentine surfaces, in the present study showed significantly larger areas of resorption in infected roots compared to non-infected roots, while cementum surfaces showed an almost identical distribution of tissue reactions regardless of root canal infection or not. It was concluded that endodontic pathogens or their products were not able to penetrate the cementum barrier. The significantly larger areas of resorption on exposed dentine surfaces in infected roots compared to non-infected roots indicated that endodontic pathogens or their products could spread through dentinal tubules to a root surface void of cementum. Extrapolated to the marginal situation this indicated that endodontic pathogens in the root canal might be able to aggravate marginal infection in areas of the root devoid of cementum.     

Effect of masticatory stimulation on dentoalveolar ankylosis after experimental tooth replantation

Abstract Dentoalveolar ankylosis (replacement resorption) is a serious complication after replantation of avulsed teeth. The purpose of the present study was to investigate the influence of masticatory stimulation on dentoalveolar ankylosis after replantation of avulsed teeth. Monkey upper incisors were extracted, air-dried for 1 h, endodontically treated and replanted. No splinting was used. One group of monkeys was given hard pelleted food, while another group was given soft diet during a healing period of 8 wk. The periodontal conditions were evaluated histologically with a morphometrical method. The replanted teeth of the monkeys given the hard pelleted food had significantly less ankylosis and a larger area of the root surrounded by a normal periodontal membrane than the teeth from the monkeys given a soft diet. In conclusion, development of ankylosis seemed to be partially prevented or reduced by masticatory stimulation.     

Emdogain® does not prevent progressive root resorption after replantation of avulsed teeth: a clinical study

Abstract –  Emdogain^® has been shown in clinical and experimental studies to promote regeneration of all periodontal tissues: cementum with anchoring fibres, a functional, periodontal ligament and alveolar bone in connection with treatment of marginal periodontitis.
The intention of this study was to analyse whether this regenerative capacity upon the periodontal ligament also worked in a trauma situation where a significant number of PDL cells have been eliminated because of unphysiologic storage or actual damage during avulsion or replantation. Furthermore if ankylosis sites already established because of earlier replantation after avulsion could be surgical removed and application of Emdogain^® could revert the ankylosis stage to a normal PDL situation. The first treatment situation was tested in seven patients with a total of 16 avulsed teeth with varying time of extra oral storage. The teeth were extra-orally endodontically treated and the root and socket covered with Emdogain^® before replantation. All teeth demonstrated subsequent ankylosis, primarily diagnosed by a percussion test. The second treatment situation where an ankylosis was already established constituted of seven patients with a total of 11 teeth because of previous replantation after avulsion. These teeth were all extracted, the ankylosis sites removed and the root and socket treated with Emdogain^®. After 6 months all teeth showed recurrence of ankylosis. It is concluded that Emdogain^® was not able to prevent or cure ankylosis.     

Effect of delayed calcium hydroxide treatment on periodontal healing in contaminated replanted teeth

Abstract – The effect of delayed intracanal calcium hydroxide treatment on experimentally induced extensive inflammatory root resorption in monkeys was studied. A significant shift from inflammatory resorption to ankylosis was noted following calcium hydroxide treatment. Furthermore, calcium hydroxide treatment appeared to change the pattern of ankylosis over time, although the total ankylotic area remained the same. Ankylosis preceded by root resorption (replacement resorption) increased, while ankylosis not associated with root resorption decreased. It was concluded that intracanal calcium hydroxide treatment of teeth with compromised PDM may cause unnecessary replacement resorption if left in the root canal for a long time or changed repeatedly.     

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.     

Tooth avulsion and replantation — A review

Abstract The major causes of post-replantation tooth loss are inflammatory root resorption and root resorption associated with ankylosis. Recent studies have concentrated on delineating the cellular interactions in the pulp and periodontium in order to more fully understand the various factors affecting the prognoses of such teeth. The aim of this report is to discuss the nature of the pathology responsible for tooth loss following avulsion and to review recent replantation and attachment studies.     

The effect of intracanal Ledermix on root resorption of delayed-replanted monkey teeth

Abstract – Progressive root resorption is one of the common sequelae in replanted teeth, which is detrimental to their long‐term prognosis. Ledermix paste, with its composition of triamcinolone acetonide and demethylclortetracycline, has been shown to inhibit inflammation and the associated hard tissue resorption. This study evaluated the effect of immediate intracanal Ledermix on root resorption of delayed‐replanted monkey teeth. A total of 36 roots were root canal treated. For the experimental group, intracanal Ledermix was placed prior to extraction and replantation after 1‐h bench dry. The positive control group was root filled and replanted after 1 h while the negative control group was root filled and replanted immediately. The monkeys were sacrificed after 12 weeks. The H&E histological tissue specimens were prepared and evaluated using a method modified from that of Andreasen's morphometric analysis, as favorable or complete healing and unfavorable healing, comprising inflammatory root resorption and replacement resorption. The results were analyzed using Kruskal–Wallis and Mann–Whitney U‐tests as well as Wilcoxon signed ranks test. The negative control group produced highly significant favorable healing and unfavorable healing as compared to the Ledermix group (P = 0.000). The Ledermix group only showed significantly higher occurrence of complete healing (35.46%) compared to the positive control group (16.58%) (P = 0.037) but there were no significant differences in the inflammatory root resorption and replacement resorption. Nevertheless, when the latter two unfavorable healing patterns were combined, there was a significantly lower overall unfavorable healing in the Ledermix group (64.54%) when compared to the positive control group (83.43%) (P = 0.037). This unfavorable healing outcome in the Ledermix group, however, was not significantly different from the favorable healing outcome with the same treatment modality (P = 0.110).     

Prognosis of permanent teeth with internal resorption: a clinical review

Abstract This study was performed in order to report the clinical features of internal resorption cases and evaluate their prognosis after endodontic treatment. Twenty-seven patients with 28 teeth with internal resorption were referred to our clinic and 20 teeth were treated endodontically. Sixteen teeth had non-perforating internal resorption and were treated by conventional root canal therapy. The remaining 4 teeth had perforating internal resorption and were initially treated by remineralization therapy with calcium hydroxide. The teeth treated by conventional root canal therapy showed clinical and radiographic evidence of healing. However, the remineralization therapy was successful in only one case. The three failed cases were subsequently treated by endodontic surgery. The surgical therapy was unsuccessful in one case due to extensive loss of marginal alveolar bone and increased tooth mobility.     

Intentional replantation and management of avulsion related ankylosis and external cervical resorption. A 10-year follow up case report

Replantation is the treatment of choice for avulsed permanent teeth; ankylosis and cervical root resorption are among survival complications. A 9.5-year-old boy presented with an avulsed maxillary permanent central incisor with an open root apex following a school accident. The tooth was kept in milk, after a dry time of 15–20 min. Its replantation was performed 60 min after the accident. At 8 months, apexification with apical plug was attempted upon radiographic evidence of apical periodontitis. Ankylosis sound with infraocclusion and radiographic evidence of external cervical root resorption (ECR) were evident at 3 years and 3 months. At the patient's return one year later with esthetic concerns (2 mm infraocclusion) there was a 5 mm diameter ECR cavity. After intentional atraumatic extraction the resorptive cavity was debrided and restored with Biodentine; subsequently the tooth was reimplanted and splinted at an extruded position. At the 10-year follow up since the first avulsion the tooth remains esthetically pleasing, asymptomatic, non-ankylotic and functional. The present case supports intentional replantation as an option in managing infraoccluded teeth with advanced ECR.     

Investigation of the children referred to a dental hospital with avulsed permanent incisor teeth

Abstract The management of children referred to a dental hospital because of avulsed permanent incisor teeth was considered in a retrospective study. The group consisted of 49 children between the ages of 6 and 14 years. Most of the children (60%) had their avulsed teeth stored dry while only 7% had them stored in milk, and 19% in saliva. Following avulsion the majority of the children attended a dental surgeon or general hospital. Twenty-three children contacted health care personnel within 30 minutes but only 13 had their teeth replanted in this time period. Thirty-six children had 46 incisors replanted. No relationship was demonstrated between the place or personnel who replanted the teeth, and a successful outcome.     

Inflammatory resorption: untreated, arrested, prevented

Abstract Three human replantation cases are presented wherein the results are in accord with the literature concerning inflammatory resorption and calcium hydroxide therapy. The cases unintentionally simulate a designed experiment wherein the control case received no treatment and the other 2 were subjected to independent variables such as obturation in the hand and the timing of the calcium hydroxide therapy. The untreated case resulted in loss of the tooth, while manipulation of variables in the other two resulted in retention.     

External root resorption following bleaching of pulpless teeth with oxygen peroxide

Abstract Eleven teeth in which bleaching with 30% oxygen peroxide was followed by external root resorption are presented. One tooth had no traumatic history, while the others were previously subluxated or luxated in accidental injury. Radiographic appearance of resorptions varied. In 2 teeth the resorptions were only superficial and did not progress during the observation time. In 5 teeth the resorptions were associated with ankylosis. In the remaining 4 teeth the resorption was progressive, bowl-shaped and associated with radiolucency in the adjacent alveolar bone. It was suggested that damage to the periodontium, caused by oxygen peroxide at the time of treatment, may heal or be followed by ankylosis and, when complicated by bacterial contamination, develop to a progressive root resorption associated with persistent inflammatory changes in periodontal tissues.     

Results after replantation of avulsed permanent teeth. I. Endodontic considerations

Abstract – Following avulsion and replantation, teeth are at risk for infection and infection related resorption (IRR). Severe discolorations of tooth crowns and cervical root fractures are common. This study presents data on endodontic related complications of avulsed teeth replanted following an extraoral endodontic treatment. Periodontal aspects will be discussed in the second part of the present publication. Twenty‐eight permanent teeth in 24 patients aged seven to 17 years were replanted after avulsion. All teeth could be evaluated. In all teeth extraoral endodontic treatment by retrograde insertion of ceramic or titanium posts was performed. Mean observation period was 31.2 months (median: 24.1 months). Nine teeth healed with a functional peridontal ligament (PDL) (functional healing, FH), 19 teeth exhibited replacement resorption (RR), which was succeeded by IRR in three teeth after observation periods of more than 14 months. Diagnosis was set to tunneling resorption (one case) and to cervical resorption preceded by complete RR (two cases). No early IRR was observed. All six teeth rescued in physiologic conditions (cell culture medium of tooth rescue box) exhibited FH. Discolorations of tooth crowns or other complications (cervical root fractures, fractures of posts) were not observed. No differences in the healing results of immature and mature teeth were observed which is in contrast to previous studies. This finding is explained with the different endodontic treatment protocols. Extraoral endodontic treatment by retrograde insertion of posts prevents early IRR and minimizes the overall incidence of IRR. The method does not negatively influence periodontal healing. As there are further advantages (no discoloration, no root fractures, patient not involved, less radiographs, less time consumption, less costs) the method is recommended in isolated teeth before replantation. Especially immature teeth profit from the prevention of complications.     

Endodontic treatment of experimental root perforations in dog teeth

Abstract Experimental root perforations were made in 131 teeth of 5 mongrel dogs. The perforations were treated according lo five different endodontic techniques and the results were observed after 3 weeks, 3 months and 1 year. The histologic reaction was dominated by inflammation and downgrowth of gingival epithelial tissue, regardless of observation time, technique or material Used. The epithelial downgrowth resulted in the formation of periodontal pockets with the epithelial attachment apical to the perforation. The frequency of the periodontal pockets increased with increasing observation time and after 1 year 75% of the perforations were lined with epithelium. The inflammation at the perforation site apparently was maintained by irritants from the periodontal pockets.     

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.     

Timing of calcium hydroxide therapy in the treatment of root resorption in replanted teeth in dogs

Abstract The effect of time of the onset of calcium hydroxide (CH) pulpectomy on root resorption of 31 permanent dog incisors was investigated. CH pulpectomy was delayed 4, 9, 14 and 18 days after the teeth were extracted and replanted. Control teeth were replanted 1) without pulpectomy, 2) with a pulpectomy only or 31. with a pulpectomy and CH filling. All teeth were prepared for histologic evaluation 8 weeks after the teeth were replanted. Cross section were examined using a computer microscope and linear (jam) and/or square areas (μm²) of surface (SRR), inflammatory (IRR), and replacement (RRR) root resorption were calculated. From this data the percentage of linear and area resorption was averaged for each group. Duncan multiple range t-test (P<0.05) revealed that teeth in which a pulpectomy with CH filling was done extraorally had significantly greater SRR than the rest of the groups; teeth in which a pulpectomy without CH filling was done extra orally had significantly greater RRR than teeth in which CH pulpectomy was delayed for 18 days; there was no significant difference in SRR. IRR or RRR when CH placement was delayed 4, 9, 14 or 18 days after replantation. Although it was not significant the overall resorption was least when CH pulpectomy was delayed 18 days.     

正畸治疗对根管治疗牙及对侧同名活髓牙根吸收影响的Meta分析

目的    分析正畸治疗对根管治疗牙及对侧同名活髓牙根吸收的影响。方法    计算机检索Cochrane Library、PubMed、Embase、Google Scholar、中国知网、万方等数据库,查找研究根管治疗牙经正畸治疗后牙根吸收情况的相关文献。应用Meta分析比较正畸治疗对根管治疗牙及对侧同名活髓牙根吸收的影响。结果    纳入了10篇相关文献。Meta分析结果发现,正畸治疗患者根管治疗牙根吸收情况与对侧同名活髓牙比较,差异无统计学意义（P > 0.05）。在男性正畸治疗患者中,根管治疗牙牙根吸收量小于对侧同名活髓牙,差异有统计学意义（P < 0.05）;而女性正畸治疗患者两侧牙根吸收量比较,差异无统计学意义（P > 0.05）。正畸治疗方式（拔牙矫治与非拔牙矫治）和牙位（前牙与后牙）对正畸治疗患者根管治疗牙及对侧同名活髓牙根吸收的影响比较,差异均无统计学意义（均P > 0.05）。结论    正畸治疗过程中移动根管治疗后的牙齿是一种相对安全的操作。