External Replacement Resorption Research Articles

Intraoral Radiographic Interpretation Agreement Between Veterinary Students, Veterinary Dental Residents and Veterinary Dental Specialists.

This study evaluated observer variations in the interpretation of radiographic evidence for periodontal disease, tooth resorption, and endodontic disease in dogs. Forty dental radiographs were evaluated for 12 different parameters (periapical destruction of bone, wider than expected root canal, narrower than expected root canal, apical root resorption, loss of alveolar bone, external surface resorption, external replacement resorption, external inflammatory resorption, external cervical root resorption, internal surface resorption, internal replacement resorption, internal inflammatory resorption). Interpretations by 20 veterinary dentists, 10 veterinary dental residents, and 10 veterinary students were analyzed for consistency within groups and between groups by intraclass correlation coefficients (ICCs [95% CI]). Additionally, the agreement rate between groups compared to histopathological diagnosis, when available, and to a consensus group were evaluated. The results showed fair to good interobserver agreement for all participants when looking at all questions simultaneously (0.578 [0.515-0.635]) and with the consensus group (0.483 [0.451-0.517]). However, questions pertaining to various types of tooth resorption scored the lowest ICCs ranging from 0.005 (-0.311 to 0.321) to 0.189 (-0.105 to 0.402) across individual groups. Students had the lowest agreement compared to the consensus group for all questions (0.383 [0.347-0.421]) with fair to good agreement involving groups of residents (0.501 [0.465-0.538]), recently boarded diplomates (0.541 [0.506-0.578]), and more experienced diplomates (0.545 [0.510-0.582]). While dental radiographs are essential for clinical decision making, this study shows that interpretation of radiographs is highly subjective.

Pathogenesis of non-infection related inflammatory root resorption in permanent teeth: A narrative review.

The mechanism of action of root resorption in a permanent tooth can be classified as infection-related (e.g., microbial infection) or non-infection-related (e.g., sterile damage). Infection induced root resorption occurs due to bacterial invasion. Non-infection-related root resorption stimulates the immune system through a different mechanism. The aim of this narrative review is to describe the pathophysiologic process of non-infection-related inflammatory processes involved in root resorption of permanent teeth. A literature search on root resorption was conducted using Scopus (PubMed and Medline) and Google Scholar databases to highlight the pathophysiology of bone and root resorption in non-infection-related situations. The search included key words covering the relevant category. It included in vitro and in vivo studies, systematic reviews, case series, reviews, and textbooks in English. Conference proceedings, lectures and letters to the editor were excluded. Three types of root resorption are related to the non-infection mechanism of action, which includes surface resorption due to either trauma or excessive orthodontic forces, external replacement resorption and external cervical resorption. The triggers are usually damage associated molecular patterns and hypoxia conditions. During this phase macrophages and clastic cells act to eliminate the damaged tissue and bone, eventually enabling root resorption and bone repair as part of wound healing. The resorption of the root occurs during the inflammatory phase of wound healing. In this phase, damaged tissues are recognized by macrophages and neutrophiles that secrete interlaukines such as TNF-α, IL-1, IL-6, IL-8. Together with the hypoxia condition that accelarates the secretion of growth factors, the repair of the damaged perioduntiom, including damaged bone, is initiated. If the precementum and cementoblast are injured, root resorption can occur. Wound healing exhibits different patterns of action that involves immune stimulation in a bio-physiological activity, that occurs in the proper sequence, with overlapping phases. Two pathologic conditions, DAMPs and hypoxia, can activate the immune cells including clastic cells, eliminating damaged tissue and bone. Under certain conditions, root resorption occurs as a side effect.

The outcomes of auto-transplanted premolars in the anterior maxilla following traumatic dental injuries.

Tooth auto-transplantation is a treatment option, which is often not considered to replace anterior maxillary incisors in children and adolescents. There are multiple prognostic factors that may influence the outcomes of premolar auto-transplantation, but there is limited evidence from human studies. The aim of this study was to report the outcomes of auto-transplanted premolars in the anterior maxilla following traumatic dental injuries (TDIs) and to identify their prognostic factors. The clinical records of patients who had premolars transplanted in the anterior maxilla following TDI, with appropriate radiographs and a minimal of 1-year follow-up, were reviewed retrospectively. A specific data extraction form was developed, tested and used to collect information for the prognostic factors and outcomes. The cohort included 120 patients with 144 auto-transplanted premolars. The mean age was 12.2 years (±2.0), and the mean observation period was 3.7 years (±1.8). The success rate was 80%, and the survival rate was 93%. Unfavourable outcomes included external replacement resorption in 12.5%, uncontrolled external inflammatory resorption in 2.7%, and both resorption types in 4.9% of teeth. Periodontal healing was significantly associated with donor tooth root maturity, graft handling at the time of surgery including ease of donor tooth extraction and placement at the recipient sites, recipient site alveolar bone status, and post-operative transplant mobility. Seventy-four teeth (53.4%) were immature at the time of transplantation where pulp revascularisation was anticipated, and 52 (70%) of those had radiographic and clinical signs of pulp healing. Pulp healing was significantly related to donor tooth eruption stage, ease of extraction of donor tooth, and ease of placement in the recipient site. Good outcomes were observed for premolar teeth auto-transplanted in the anterior maxilla. The main prognostic factors were ease of extraction of donor tooth and ease of placement in the recipient sites and donor tooth root maturity.

Pattern of Root Resorption in Luxation Injuries in Permanent Incisors Presented to Restorative Unit , Institute of Oral Health, Maharagama – Sri Lanka

The aim of this descriptive study was to evaluate the association between root resorption and each type of luxation injury, the effect of timely treatment, age of the patient at presentation and maturity of maxillary anterior teeth presented with luxation injuries. A cross sectional descriptive study was carried out on 132 patients aged 6 to 50 years old with luxation injuries occurred to 213 teeth and were followed up for 24 months. Data were collected on the age, sex, the tooth/teeth involved, type of trauma, date of occurrence of trauma and date of presentation for treatment. Radiographically teeth were assessed for the presence/absence of resorption and type of resorption (External inflammatory, external replacement and Internal inflammatory) at review appointments. Data analysis was done using the SPSS version- 24 and non- parametric tests were used assess associations. Amongst all types of luxation injuries, most frequently presented type was subluxation (40.8%) injuries followed by concussion (25.4%), Intrusive and palatal luxation (15.5% each) and extrusive luxation (2.8%) respectively. Further, 51 of 213 teeth (23.9%) showed root resorption after luxation injury. The most frequently observed resorption was external inflammatory resorption in 44 teeth (20.7%) followed by external replacement resorption in 6 teeth (2.8%) and internal inflammatory resorption in 1 tooth (0.5%). Out of 43 late presenters 77% (34) showed root resorption, while only 10% (17) of immediate presenters showed resorption of root. The results indicated that there is a statistically significant difference in occurrence of root resorption and the late presentation for treatment (X2=91.63, df=3, p=0.000), as well as with the type of injury (X2=35.9, df=12, p=0.000). Furthermore, there was a statistically significant difference between the age of the patient and the type of luxation injury (X2 =54.29, df-12, P=0.000).

Three-Dimensional Volumetric/ Linear Analysis and Axial Classification of Root Resorptions Using Cone Beam Computed Tomography: A Retrospective Study

Objectives: The purpose of this study was to investigate the volumetric-linear analysis and to present a new axial classification of root resorptions using cone-beam computed tomography (CBCT). 
 Materials and Methods: A total of 43 teeth with root resorption (external cervical resorption (ECR) (n=27), external replacement resorption (ERR) (n=4) and internal root resorption (IRR) (n=12)) from 34 patients were included in this study. On CBCT images of teeth, the volume of total tooth and resorption for the volumetric analysis, the widest lengths of resorptions and the amount of thinnest dentin thickness around them for the linear analysis were measured, and volumetric/linear measurements were compared according to age and gender. In addition, the eight regional axial classification was performed, and these regions were compared. Data were evaluated using Shapiro-Wilk, Pearson’s r., Kruskal-Wallis and Dwass-Steel-Critchlow-Fligner post-hoc tests. Significance was set at p=0.05 for statistical analysis.
 Results: No significant difference was found between the volumetric and linear measurements of ECRs, ERRs, and IRRs. No difference between genders in volumetric and linear measurements of ECRs and IRRs, except total tooth volume, was higher in males than in females in ECRs (p

Traumatic dental injures on maxillary incisors and its sequelae after 22-years follow-up: a case report

Avulsion of a permanent tooth is a serious condition and a true dental emergency that can be associated with other traumatic injuries. In addition, in reimplanted avulsed teeth, ankylosis and external replacement resorption (ERR) are two typical biological responses, with long-term progression and outcome associated with the patient's growth stage. The purpose of this report is to present the long-term outcome of an 18-year-old patient who was the victim of a motor vehicle traffic accident that resulted in traumatic injury to the maxillary incisors, including an avulsed central incisor with extensive external replacement resorption (tooth 11). Twenty-two years later, due to the continuous effect of the ERR process on the reimplanted tooth and favorable bone weight, it was decided to perform rehabilitation with immediate guided implant by a simplified method (KEA-TECH system). In young patients, the decision to maintain the tooth even under unfavorable conditions may delay rehabilitation with implants.

Long‐term retention of avulsed maxillary permanent incisors replanted after prolonged non‐physiological storage

Ankylosis and external replacement resorption (ERR) are two typical biological responses to delayed replantation of avulsed teeth in cases where adequate root canal treatment is performed. The patient's growth stage affects the progression of root resorption and the long-term outcome of the affected teeth. This case report describes the long-term outcome of an 18.5-year-old patient following an accident in which both of his maxillary central incisors were avulsed and replanted after four hours of non-physiological storage. ERR and ankylosis of teeth 11 and 21 were detected clinically and radiographically during the second year of follow-up. Sixteen years after replantation, replacement resorption was progressing very slowly, enabling functional tooth retention with favorable esthetics. Young adults, with delayed replantation of avulsed teeth, may benefit from tooth retention with slow ERR.

Oral and dental anomalies in purebred, brachycephalic Persian and Exotic cats.

OBJECTIVE To determine the prevalence of dental anomalies in brachycephalic cats from various geographic regions and analyze potential relationships with oral disease. DESIGN Prospective multicenter cross-sectional study. ANIMALS 50 purebred Persian (n = 42) and Exotic (8) cats. PROCEDURES Cats were anesthetized, and a complete dental examination, dental charting, 3-view oral photography, and full-mouth dental radiography were performed. RESULTS Malocclusions were observed in 36 (72%) cats. Crowding of the teeth was evident in 28 (56%) cats, with the incisors being most commonly affected. Malpositioned teeth were noted in 32 (64%) cats, with abnormal orientation being the most common anomaly followed by rotation and impaction. Numerical abnormalities were present in 38 (76%) cats, including 6 (12%) with hyperdontia and 32 (64%) with hypodontia. Periodontal disease was reported in 44 (88%) cats, and cats with periodontal disease were older than cats without. Tooth resorption was evident in 35 (70%) cats. Overall, 123 of 1,349 (8.7%) teeth had external inflammatory resorption and 82 (6.1%) had external replacement resorption. The premolar teeth were the teeth most commonly affected with inflammatory resorption, whereas the canine teeth were the teeth most commonly affected with replacement resorption. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that because of their brachycephaly, Persian and Exotic cats have unique oral and dental features that may predispose them to dental disease (eg, tooth resorption and periodontal disease). Knowledge of the particular dental anomalies common in brachycephalic cats could aid in early detection and mitigation of dental disease in these breeds.

The enigma behind complete external replacement resorption of replanted permanent incisor - A case report

The enigma behind complete external replacement resorption of replanted permanent incisor - A case report

Radiographic evaluation in clinical practice of the types and stage of incisor tooth resorption and hypercementosis in horses.

There are several reports of incisor tooth resorption and hypercementosis in horses but, to date, studies have been limited in case numbers and to advanced lesions. Tooth resorption in other species is a radiographic diagnosis of types of resorption that are often identified before clinical signs. Our goal was to evaluate radiographically incisor tooth resorption in a large population of horses, utilising interpretation criteria from canine and human dentistry. To document and classify incisor tooth resorption and hypercementosis. Retrospective descriptive case series. Horses presented for routine dental care >5 years old were included only if owners were unaware of incisor pathology. Radiographs (three views) were obtained of the incisor teeth and incisor teeth resorption was classified according to the radiographic criteria described for man and dogs. Hypercementosis and its location were recorded. Tooth resorption was detected in 149 of 169 (88.2%) horses and 951 of 1952 (48.7%) of incisor teeth. The classification system used was applicable in 926 (97.2%) of 951 affected teeth. Hypercementosis was detected in 34 (20.1%) horses and 148 (7.6%) teeth. As horses increased in age, resorption and hypercementosis was more frequent; no significant differences were found among sex or breed categories. All horses with hypercementosis had resorption, but only 23.4% of horses with resorption had hypercementosis. Advanced (stage ≥3) resorption was detected in 159 (8.1%) teeth and 54 (32.0%) horses in an otherwise clinically healthy population. Certain horses' anatomy precluded isolation of the mandibular third incisor teeth from the canine teeth due to superimposition. Incisor tooth resorption, in particular external replacement resorption and external inflammatory resorption, is common in horses. Hypercementosis is consistently associated with resorption, but the inverse association is inconsistent.

External replacement resorption in an avulsed reimplanted permanent incisors

External replacement resorption in an avulsed reimplanted permanent incisors

External replacement resorption in an avulsed reimplanted permanent incisors

An avulsed permanent tooth is one of the few real time dental emergencies, wherein a potential unscheduled diagnostic and treatment decision outside the regular practice experience of the dentist awaits him. Prognosis is dependent on the decisions taken in the Golden Hour aftermath the accident. Reimplantation is the treatment of choice as there are chances of successfully saving a tooth. The condition is compounded by the lack of public awareness and the presence of a proper avulsion management protocol that has been tested by prospective longitudinal studies. This article discusses an unusual case of total replacement resorption along with a comprehensive review of the etiology, pathology, clinical features, and the management of the condition.

Osseointegration at implants placed into delayed reimplanted roots: An experimental study in dogs

To evaluate peri-implant bone repair of implants placed into the roots of delayed reimplanted teeth, in a process of ankylosis and external replacement resorption. The third and fourth mandibular premolars of four (4) beagle dogs were used as experimental sites. The study was divided into three stages: stage 1 - endodontic and extraction/reimplantation session, stage 2 - decrowning session and stage 3 - implant placement. Two groups were identified: (I) immediate implants, including implants installed in fresh extraction sockets of the distal roots, and (II) experimental implants, including implants installed into the retained ankylotic mesial roots. In each group, 16 implants were planned to be inserted, but only 9 immediate implants and 12 experimental implants were used for analyses. Implants were intended to heal in a submerged mode. After 4 months of healing, the animals were sacrificed and ground sections were obtained for histomorphometric evaluation. Eleven of the twelve implants in the experimental group were found successful regarding clinical and radiographic aspects. For immediate implants, a lower BIC% was found at the coronal portion (BIC% 1 = 42.2%) compared with the three most coronal threads portion (BIC% 2 = 55.1). Also, experimental implants presented a lower BIC% at the coronal portion (BIC% 1 = 36.9%) compared with the three most coronal threads portion (BIC% 2 = 45.3). Comparison between groups showed a higher degree of BIC% and mineralization in immediate group compared with experimental group. The differences, however, did not yield statistical significance.

A 5-year follow-up case of multiple intrusive luxative injuries

Introduction: Traumatic intrusive luxation is one of the most severe forms of dental injuries, usually affecting the maxillary incisors. The consequence of such an occurrence is a high risk of healing complications such as pulp necrosis, external inflammatory resorption, and external replacement resorption (ankylosis). Case Report: This report presents a case of severe intrusive luxation of multiple anterior teeth in an 11-year-old girl. The teeth were repositioned successfully by endodontic and orthodontic management. The case was monitored for 5 years. Discussion: Depending on the severity of the injury, different clinical approaches for treatment of intrusive luxation may be used. Despite the variety of treatment modalities, rehabilitation of intruded teeth is always a challenge and a multidisciplinary approach is important to achieve a successful result. In this case, intruded teeth were endodontically treated with multiple calcium hydroxide dressings and repositioned orthodontically. The follow-up of such cases is very important as the repair process after intrusion is complex. After 5 years, no clinical or radiographic pathology was detected.

Radiographic evaluation of the classification of the extent of tooth resorption in dogs

To determine applicability of the 2007 American Veterinary Dental College (AVDC) classification method for determining extent of tooth resorption in dogs. 224 dogs > 1 year old admitted for periodontal treatment or other dental procedures in 2007. Full-mouth radiographs of all dogs were reviewed for evidence of tooth resorption. Tooth resorption in dogs was classified in accordance with the radiographic criteria described for use in human teeth and, when applicable, the guidelines described in the 2007 AVDC classification method. 851 of 943 (90.2%) affected teeth met the radiographic characteristics of 1 of the 5 stages of tooth resorption described by the AVDC classification method. Among tooth resorption types described for human teeth, the AVDC classification method was totally applicable (100%) in 17 teeth with external surface resorption, 21 teeth with external replacement resorption, and 736 teeth with external cervical root surface resorption, but it was applicable in only 56 of 121 (46.3%) teeth with external inflammatory resorption and none of the teeth with internal resorption. The AVDC classification method was useful to describe the extent of tooth resorption in dogs, but it did not reflect the radiographic patterns and location of lesions. The AVDC classification method was applicable in some, but not all, of the teeth with various resorption types in dogs. The AVDC classification method could be adapted best to lesions that have radiographic patterns of external replacement resorption and external cervical root surface resorption.

Radiographic evaluation of the types of tooth resorption in dogs

To determine the prevalence of tooth resorption in dogs and to evaluate whether a classification system for tooth resorption in humans is applicable in this species. 224 dogs > 1 year old admitted for periodontal treatment or other dental procedures in 2007. Full-mouth radiographs of all dogs were reviewed for evidence of tooth resorption. Tooth resorption was classified in accordance with radiographic criteria described for use in humans. Patient signals and concurrent dental conditions were recorded and tabulated. Tooth resorption was detected in 120 of 224 (53.6%) dogs and 943 of 8,478 (11.1%) teeth. The classification system for use in humans was applicable in 908 of 943 (96.3%) affected teeth. Tooth resorption was more frequent among older and large-breed dogs; no significant differences were found among sex categories. The 2 most common types of tooth resorption were external replacement resorption (77/224 [34.4%] dogs and 736/8,478 [8.7%] teeth) and external inflammatory resorption (58/224 [25.9%] dogs and 121/8,478 [1.4%] teeth). External cervical root surface resorption was detected in 13 of 224 (5.8%) dogs; external surface resorption was detected in 10 of 224 (4.5%) dogs, and internal inflammatory resorption and internal surface resorption were detected in 9 of 224 (4.0%) and 1 of 224 (0.4%) dogs, respectively. Internal replacement resorption was not detected. The classification of tooth resorption in humans was applicable to tooth resorption in dogs. Resorption lesions, in general, and external replacement and external inflammatory resorption, in particular, were frequently detected in dogs.

Intrusive luxation of permanent incisors in Norwegians aged 6–17 years: a retrospective study of treatment and outcome

External replacement resorption (ankylosis-related) is a severe complication leading eventually to tooth loss. Little information exists regarding the influence of variables such as degree of intrusion or treatment method on the development of replacement resolution in intruded permanent incisors. The aim of this study was to report the most frequently involved age group, the preferred type of treatment, and the type and frequency of healing complications. Special attention was paid to the effect of treatment on the occurrence of replacement resorption. Fifty-one intruded permanent incisors were studied in 20 boys and 19 girls aged 6 to 17 years. Only three patients were over 12 years of age. Complete intrusion had occurred in 21 teeth, and 31 teeth were classified as immature. Re-eruption was awaited for 37 teeth. The remaining teeth were repositioned orthodontically (7 teeth) or surgically (7 teeth). Re-eruption occurred in 35 out of 37 teeth over a period of 3-12 months. After a mean observation period of 4 years ranging from 1-12 years, retained pulp vitality was recorded in 22 teeth (43%). Pulp necrosis had developed in 57%, inflammatory resorption in 26% and replacement resorption in 12%. Whereas all inflammatory resorptions were arrested after long-term calcium hydroxide treatment, replacement resorption always led to complete root resorption. In the analysis all orthodontic and surgical repositioned teeth were combined into an active treatment group. The non-active treatment group consisted of teeth allowed to re-erupt. The distribution of replacement resorption was significantly lower in teeth allowed to re-erupt than in teeth repositioned actively. The best treatment of intruded incisors in 6-12 year-old children is to await re-eruption. Should endodontic treatment be required before re-eruption has occurred, a gingivectomy can be performed to gain access to the root canal.

Use of a removable splint in the treatment of subluxated, luxated and root fractured anterior permanent teeth in children.

The aim of this study was to evaluate the prognosis of subluxated, luxated and root fractured teeth in children treated by removable splints, designed to stabilize mobile anterior teeth and eliminate occlusal trauma due to malocclusion. A total of 227 traumatized anterior teeth (91 subluxated, 105 luxated and 31 root fractured teeth) treated with a removable splint were observed for 3 years. The traumatized teeth were from 79 children aged between 6-12 years (mean 8 years 5 months). If a traumatized tooth was extremely mobile, a fixed splint was first made before the impression was taken for the removable splint. Two weeks after completion of the removable splint treatment, an impression was taken again to evaluate the occlusal relationship of pre- versus post-treatment of removable splint. The treatment period with a removable splint averaged 3 weeks in subluxated teeth, 3-5 weeks in luxated teeth, 4-6 weeks in apical third root fracture injuries, and more than 5 weeks in middle third root fracture injuries. All the subluxated teeth and 74.1% of the luxated teeth maintained their pulp vitality during the 3-year follow-up period. Two of 21 (9.5%) apical third root fracture teeth and three of five (60%) middle third root fracture teeth had pulp necrosis in the coronal fragments. Internal resorption was not found in any of the traumatized teeth. External replacement resorption was not found in subluxated and luxated teeth. All the root fractured teeth displayed transient external resorption around the fracture lines. The surface resorption appeared to be self-limiting and not to threaten the retention of the tooth. Inflammatory resorption was observed in teeth with pulp necrosis, but in all cases this was reversed with endodontic treatment. Eight of 23 (39%) apical third root fractured teeth displayed replacement resorption in their apical fragments, but the resorption was not serious enough to extract the tooth. No obvious alteration in the occlusal relationship was found comparing pre- and post-treatment casts. The removable splints appeared to positively affect healing after traumatic injuries, as evidenced by the low number of complications at the 3-year follow-up period.

Late complications of luxation injuries to teeth

Abstract The 172 periodontally injured teeth of 76 patients were examined clinically and radiographically 6–32 months (mean 22 months) following injury. Multiple linear regression analysis, in which all the variables examined were forced into the model, was used to study the effect of three variables (stage of root formation, type of luxation, and duration of immobilization) in conjunction with one or two variables having the highest explanatory effect on 4 radiographically diagnosed late complications: external replacement resorption, pulp obliteration, loss of marginal alveolar bone and periapical inflammatory changes. External root resorption was found in 19% of cases and was only statistically related to the type of first aid treatment (p< 0.001), although the duration of immobilization was a more decisive factor for ankylosis than the other two variables. Partial or total obliteration of the pulp was recorded in 24% of the teeth examined and was statistically related to the age of the patient (p< 0.001) and the stage of root formation (p<0.05). Loss of marginal alveolar bone was dependent on the age of the patient (p< 0.001) and the duration of immobilization (p<0.05). Dislocation upon injury was the most decisive single factor affecting the radiographic periapical inflammatory changes (p<0.001).