Healing of 400 intra-alveolar root fractures. 2. Effect of treatment factors such as treatment delay, repositioning, splinting type and period and antibiotics

Abstract –  This is the second part of a retrospective study of 400 root-fractured permanent incisors. In this article, the effect of various treatment procedures is analyzed. Treatment delay, i.e. treatment later than 24 h after injury, did not change the root fracture healing pattern, healing with hard tissue between fragments (HH₁), interposition of bone and/or periodontal ligament (PDL) or pulp necrosis (NEC). When initial displacement did not exceed 1 mm, optimal repositioning appeared to significantly enhance both the likelihood of pulpal healing and hard tissue repair (HH₁). Significant differences in healing were found among the different splinting techniques. The lowest frequency of healing was found with cap splints and the highest with fiberglass or Kevlar^® splints. The latter splinting procedure showed almost the same healing result as non-splinting. Comparison between non-splinting and splinting for non-displaced teeth was found to reveal no benefit from splinting. With respect to root fractures with displacement, too few cases were available for analysis. No beneficial effect of splinting periods greater than 4 weeks could be demonstrated. The administration of antibiotics had the paradoxical effect of promoting both HH₁ and NEC. No explanation could be found. It was concluded that, optimal repositioning seems to favor healing. Furthermore, the chosen splinting method appears to be related to healing of root fractures, with a preference to pulp healing and healing fusion of fragments to a certain flexibility of the splint and possibly also non-traumatogenic splint application. Splinting for more than 4 weeks was not found to influence the healing pattern. A certain treatment delay (a few days) appears not to result in inferior healing. The role of antibiotics upon fracture healing is questionable.     

The effect of saline storage before replantation upon dry damage of the periodontal ligament

Abstract The effect of 30 min of saline storage before replantation of teeth, which had been dried out for 30 min, was studied in 10 Green Vervet monkeys (Cercopithecus aethiops). Maxillary central incisors were extracted and dried out for 30 min, after which 1 incisor was replanted and the other transferred to a saline solution for 30 min before replantation. No splinting or endodontic treatment was carried out. The teeth were examined after 8 wk. Histometric analysis showed identical extent of root resorption in the 2 groups, with ankylosis being the dominant resorption type, and with very limited pulpal repair in either group. It is concluded that saline storage under the experimental conditions chosen had no effect on development of root resorption or pulpal repair, presumably because 30 min dry storage had inflicted close to maximal damage on the periodontal ligament at the root surface. On the other hand, it is of clinical importance that a certain delay in the replantation procedure does not influence periodontal and pulpal healing, as long as the tooth is kept in saline storage. This suggests that replantation under these conditions can be reserved for dental professionals, rather than favoring immediate replantation by anyone ‘on-the-spot’.     

Transient root resorption after dental trauma: the clinician's dilemma

The diagnostic shortcomings encountered in the clinical evaluation of pulpal and periodontal healing subsequent to trauma comprise a major problem in dental traumatology. An acute dental trauma may imply impact to the hard dental tissues and damage to the pulp and periodontium (including surrounding alveolar bone). In the case of luxation injuries, the trauma often results in rupture of the neurovascular supply at the level of the apical foramen, whereas in a root fracture, the same occurs at the level of the fracture. Conventional diagnostic criteria for pulpal status (coronal discoloration, loss of pulpal sensibility, tenderness to percussion, and radiographic change [i.e., resorption]) reflect, only indirectly, certain parameters of healing. These parameters are based empirically on clinical findings after dental caries and dental restorative techniques, where the pulp has an intact neurovascular supply apically. In these situations, long-standing bacterial or chemical attack can lead to irreversible change. In contrast, following traumatic impact, a presumably intact pulp is deprived of its neurovascular supply instantaneously. In the absence of infection, events following acute dental trauma aim at either tissue repair or regeneration. Thus, based on a series of long-term clinical studies, it was found that all conventional signs, with the exception of tenderness to percussion, could be signs of pulpal healing, as well as signs of pulpal death. Based on the results of these studies, this report discusses the significance of radiographic change (resorption) in relation to pulpal and periodontal healing following acute trauma. Moreover, implications of tooth luxation with respect to the long-term prognosis following crown, crown-root, and root fractures are discussed. CLINICAL SIGNIFICANCE: Whenever possible, it is to the patient's advantage that pulp vitality be preserved. Correct diagnostic techniques and patient selection enable the clinician to decide when endodontic therapy is appropriate and when intelligent observation is the "treatment" of choice.     

Pulpal healing after luxation injuries and root fracture in the permanent dentition

Abstract Pulpal healing patterns were studied in a clinical material of 637 luxated and 95 root-fractured permanent incisors followed routinely for up to 11 years. It was found that pulpal healing patterns could generally be divided into 3 groups according to the degree of injury sustained by the pulp: little, moderate or severe. Thus after luxation injuries, pulp survival could be without radiographic change (PS), with pulp canal obliteration (PCO) or nonhealing (pulp necrosis (PN)). After root fracture, similar healing patterns could be observed: healing by hard tissue union of fragments (HT), by connective tissue union of fragments (CT) or by nonunion due to interposition of granulation tissue between fragments (GT) resulting from PN of the coronal fragment. In both trauma situations, healing or nonhealing could be determined by type of luxation injury, stage of root development and type of fixation used (forceful application of orthodontic bands vs. passively applied acid-etch fixation). Pulpal healing complications (PN or GT) were based on clinical findings (coronal discoloration, loss of pulpal sensibility) and radiographic findings (resorption processes of the lamina dura at the root apex or at the level of the root fracture). However, in both injury groups the same changes could also be seen to be intermediate steps in the pulpal healing process. Based on findings from these studies, hypotheses for the mechanics of pulpal healing are proposed as well as guidelines for acute and later treatment of dental luxations, root fractures and the diagnosis of healing complications.     

Effects of multiple dentinal lesions on the rat pulp

The purpose of this study was to compare the effects of single and multiple dentinal lesions on the dental pulps of rats. 3H-proline was used to measure pulpal reactionary dentin deposition, and 3H-thymidine was used to measure pulpal cell proliferation by radioautography. Data were compared by factorial analysis of variance and a post-hoc Tukey test. A significant increase in radiolabeled collagenous proteins within reactionary dentin and pulpal cell labeling indices were evident coincident to single dentinal injuries, compared with controls (p < 0.001). After double injuries, the radiolabeled collagenous proteins within reactionary dentin and the pulpal labeling indices remained significantly greater than in controls (p < 0.01); however, each was significantly less than after single injuries (p < 0.05). These data suggest that pulpal cell proliferation and collagenous protein deposition into reactionary dentin are decreased subsequent to a previous dentinal injury. Thus, the healing potential of the dental pulp could be decreased by recent tooth cavity preparation.     

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??Objective    To study the mechanism of periodontal tissue repair of transplanted tooth by analyzing the imaging and histological changes of autogenous transplanted tooth in Beagle dog. Methods    For a 8-months-old beagle??the left mandibular premolar region was used as receptor region for autologous tooth transplantation of anterior teeth. X-ray examination was done after operation to observe the periodontal healing of transplanted teeth. Results    X-ray at one month after operation showed that the No.1 tooth ??left mandibular second premolar?? has a narrowed periodontal gap??a small periapical radiolucency and external resorption at tooth neck; No. 2 tooth ??the left mandibular first premolar?? has a internal resorption in the upper 1/3 root canal. Two-month post-operative X-ray examination indicated the periodontal healing of transplanted teeth was perfect. The external resorption of No. 1 tooth enlarged and internal resorption of No. 2 tooth remained the same. HE staining results showed that new fibrous bundle was formed at the root tip. A large number of lymphocytes and some plasmocytes exited at the tooth neck??pulp cavity and root tip. Conclusion    Autogenous tooth transplantation can achieve good periodontal membrane healing. It is important to reduce the mechanical damage to tooth neck while pulling out the teeth. The timing of the dental pulp treatment after transplantation is one of the key elements to reduce postoperative complications.     

Apexification of a replanted tooth using mineral trioxide aggregate

Abstract –  The most important factors determining periodontal healing after replantation of an avulsed tooth are the extra oral period and the media in which the tooth is preserved before replantation. This case report describes an adequate periodontal healing of an avulsed immature tooth replanted after 20 min of extra alveolar dry time. Vitality was not regained and after disinfection of the pulp space mineral trioxide aggregate was used as the root filling. Follow-up confirmed complete healing periradicularly.     

A long-term follow up of spontaneously healed root fractures later subjected to orthodontic forces – two case reports

Abstract –  There is evidence that many dental injuries which result in root fractures may not require active treatment in cases where the coronal fragment is minimally displaced and does not exhibit clinical signs or symptoms. This paper discusses two individual cases where spontaneous root fracture healing was observed and this healing was apparently not compromised by later orthodontic tooth movement. The observation periods for the two cases were 13 and 18 years since the original root fractures occurred.     

Contradictions in the treatment of traumatic dental injuries and ways to proceed in dental trauma research*

Abstract – Almost all treatment procedures used for dental traumas are still today not evidence‐based, a fact, which makes it difficult to analyse the long‐term outcome of healing and its relationship to treatment. Crown fractures with extensive dentin exposure represent a dominant injury in the permanent dentition. Accepted treatment philosophy is dentin coverage (dental liner and/or dentin bonded restoration) to prevent bacteria penetration into the pulp. Today there is, apart from deep proximal fractures, no evidence that this treatment is necessary to protect the pulp. In case of luxation injuries, the accepted treatment principles appear to be anatomically correct repositioning, stabilization with a splint and sometimes antibiotic coverage. In clinical studies, these principles could not be proven to optimize either periodontal or pulpal healing, the explanation possibly being that both reposition and application of splints in certain cases add extra damage to the pulp and periodontal ligament. In case of root fractures with dislocation, fast and optimal repositioning and rigid long‐term splinting (i.e. 3 months) have been considered the principle of treatment. However, a recent clinical study has shown that short‐term splinting with a semi‐rigid splint appears to optimize fracture healing. In tooth avulsion with subsequent replantation, cleansing of the root surface for contamination and systemic antibiotics has been considered essential for pulp and periodontal healing. These treatment concepts have been derived from experimental studies in animals. However, their importance could not be verified in large clinical studies. Ideally, randomized clinical studies are needed in the future for selected trauma types. The influences of repositioning, splinting and the role of infection and antibiotics should be further investigated. However, for ethical reasons, it will be difficult to perform randomized studies on trauma victims and we will be forced in the future to rely on experimental animal studies supported by clinical observational studies.     

Follow-up study of permanent incisors with enamel fractures as a result of an acute trauma

Abstract – The present investigation evaluated the prognosis for vitality after and acute trauma in 2891 permanent incisors with enamel fracture as the only damage, and in 476 incisors with enamel fracture combined with other symptoms on the damaged tooth. Pulpalnecrosis developed in 57 teeth (1.7%). Acute treatment in connection with enamel fracture was only performed in half of the cases and had no importance on vitality. The combination of enamel fracture and concussion or mobility resulted in pulpal necrosis in 8.5% of cases, and cases involving both mobility and concussion meant pulpal necrosis in 14% of teeth. The findings clearly illustrated that an enamenamel fractures is an injury with an extremely favorable prognosis, and that the risk group can be narrowed to cases of combined injuries involving the supportive tissue.     

Repair characteristics of horizontal root fracture: a case report

Abstract  – Radicular fractures in permanent teeth are uncommon injuries among dental traumas, comprising 0.5–7% of the cases. Fracture occurs most often in the middle-third of the root and rarely at the apical-third. The present paper reports a clinical case of a horizontal radicular fracture located between the middle- and apical-third of a upper left-central incisor followed-up for over 3 years. The tooth was extracted owing to periodontal reasons. Histomorphologically, it showed pulp-vitality preservation and root healing by hard-tissue deposition.     

Replantation of 400 avulsed permanent incisors. 1. Diagnosis of healing complications

Abstract A material of 322 patients with 400 avulsed and replanted permanent teeth were followed prospectively in the period from 1965 to 1988 (mean observation period=5.1 yrs). The age of the patients at the time of replantation ranged from 5 to 52 yrs (mean =13.7 yrs and median =11.0 yrs). Standardized patient records were used through the entire period in order to obtain valid data concerning the extent of injury and treatment provided. At the follow–up period, pulpal and periodontal healing were monitored by clinical examination, mobility testing and standardized radio–graphic controls. Thirty–two of the replanted teeth (8%) showed pulpal healing. When related to teeth with incomplete root formation, where pulpal revascularization was anticipated (n = 94) the frequency of pulpal healing was 34%. Periodontal ligament healing (i.e. with no evidence of external root resorption) was found in 96 teeth (24%). Gingival healing was found in 371 teeth (93%). During the observation period, 119 teeth (30%) were extracted. Tooth loss was slightly more frequent in teeth with incomplete root formation at the time of replantation than in teeth with completed root formation.     

Multidisciplinary approach of complicated crown fractures of both superior central incisors: a case report

Abstract –  Anterior crown fractures are a common form of traumatic dental injuries that mainly affect the maxillary central incisors, in children and teenagers. Since the development of the adhesive dentistry, many case reports of crown fractures restored using adhesive reattachment techniques were published. Complex cases, in which more than one tooth are involved, with fractures differing from each other, require specific treatment of each fracture, taking different advantages of the different remaining tooth structures. This case report describes a patient with dissimilar crown fractures of both superior central incisors. After the endodontic treatment, the patient was treated using the combination of several techniques: periodontal surgery (crown lengthening with apically repositioned flap and osseous resective surgery), adhesive technique and cast restoration plus esthetic crown. The periodontal procedure re-created the biologic width and proved to be a reliable adjunctive procedure to the adhesive and the prosthetic techniques used.     

The treatment of an avulsed maxillary central incisor by transplantation of an embedded mandibular premolar

Abstract  – Avulsion, following traumatic injuries, is relatively infrequent. The treatment of avulsed teeth is by replantation of the avulsed tooth into its own socket. However, sometimes the avulsed tooth cannot be found at the accident site. We report a case in which the avulsed maxillary central incisor is replaced by an embedded lower premolar. A 2-year follow-up shows complete periodontal healing and a very satisfactory clinical result.     

Clinical outcomes for permanent incisor luxations in a pediatric population. III. Lateral luxations

Abstract –  A longitudinal outcome study was designed to identify variables that influenced tooth survival as well as pulpal and periodontal outcomes of laterally luxated permanent maxillary incisors of children and adolescents. All cases were treated between June 1988 and June 1998 in a teaching hospital clinic. Clinical and radiographic data were collected for 42 patients (26 males, 16 females) that represented 58 permanent maxillary incisors. Mean age at the time of injury was 11.4 years (range: 6.3–17.8 years). Mean follow-up time was 1460 days (range: 183–3905 days). In the entire sample ( n  = 58), no incisors required extraction. Survival analysis and logistic regression were used to identify variables significantly related to the survival and healing outcomes of these incisors. Pulp necrosis (PN) (40%) and pulp canal obliteration (PCO) (40%) were common healing complications. Proportional hazards (Cox) regression showed that PN develops within the first year. Logistic regression demonstrated that root development ( P  = 0.3, PN; P  = 0.8, PCO) and extent of lateral luxation ( P  = 0.5, PN; P  = 0.9, PCO) were not significantly related to PN and PCO. This study provides the first report of incisor survival in children and adolescents following lateral luxation injuries.     

Multidisciplinary approach to the rehabilitation of a tooth with two trauma episodes: systematic review and report of a case

Abstract – Studies have shown that some children and adolescents are affected only once with dental trauma, while others seem to be accident‐prone and suffer from multiple dental trauma episodes. Less is known about treatment consequences related to repeated traumatic dental injuries to the same tooth and treatment guidelines are not well established. Complicated crown fractures and crown‐root fractures pose difficulties for dentists to establish adequate treatment plans because these fractures require multidisciplinary knowledge and approach for a correct case planning and prognosis. The objective of this paper was to present and discuss a case of a child who sustained a second trauma to the same tooth following treatment of an earlier sustained crown fracture. The research‐based background for establishment of the treatment plan is discussed. Reattachment of tooth fragment is a minimal invasive and esthetic method. Essential advantage of the reattached teeth is the fact that all the alternative methods as direct adhesive resin reconstruction, veneers and crowns can be performed in case of failure or a refracture. As a consequence of initial trauma, the tooth suffered a complicated crown fracture which was resolved by endodontic therapy and fragment reattachment. During follow‐up, the child suffered a second trauma resulting in dislodgement and fracture of the reattached fragment and a crown‐root fracture extending subgingivally with involvement of the biologic width. A conservative restorative option is described. After 1 year of follow‐up, the clinical and radiographic findings demonstrated that the adopted clinical protocol was successful and yielded healthy periodontal tissues with no signs of periradicular pathosis. The occurrence of repeated traumatic dental injuries to teeth involving conservative management of both crown‐root fracture and complicated crown fracture on the same tooth is extremely rare and a challenge for dental professionals to treat.     

Endodontic or dental implant therapy: the factors affecting treatment planning

BACKGROUND: Clinicians are confronted with difficult choices regarding whether a tooth with pulpal and/or periapical disease should be saved through endodontic treatment or be extracted and replaced with an implant. METHODS: The authors examined publications (research, literature reviews and systematic reviews) related to the factors affecting decision making for patients who have oral diseases or traumatic injuries. RESULTS: The factors to be considered included patient-related issues (systemic and oral health, as well as comfort and treatment perceptions), tooth- and periodontium-related factors (pulpal and periodontal conditions, color characteristics of the teeth, quantity and quality of bone, and soft-tissue anatomy) and treatment-related factors (the potential for procedural complications, required adjunctive procedures and treatment outcomes). CONCLUSIONS: On the basis of survival rates, it appears that more than 95 percent of dental implants and teeth that have undergone endodontic treatment remain functional over time. CLINICAL IMPLICATIONS: Clinicians need to consider carefully several factors before choosing whether to perform endodontic therapy or extract a tooth and place an implant. The result should be high levels of comfort, function, longevity and esthetics for patients.     

Bone regeneration after surgical repositioning of impacted mandibular second molars: a case report

Abstract  – A case is presented where the mesially impacted mandibular second molar teeth were surgically uprighted in an 11-year-old female patient. Bone regeneration is shown in the areas occupied by the impacted second molars with maturation of bone and cortication of the crest of the alveolar bone. The probing depths are also normal with no residual bony defects. This healing was achieved with no bone grafting procedure, emphasizing two important factors: to prevent/minimize any trauma to the tissues at the site of elevation and uprighting of the tooth (i.e. maintaining viable periodontal ligament cells and minimal cementum damage); and to obtain primary closure whilst allowing the tissue in the mesial defect to reorganize against the scaffold of bone. However, the procedure on the one side was complicated with necrosis and infection of the pulp space with external inflammatory root resorption. Endodontic therapy of this tooth proved to be successful with periradicular healing radiographically and re-establishment of the lamina dura. At the 3-year follow-up, the endodontically treated tooth showed no clinical and radiographic signs of pathology. The left second mandibular molar had no pulpal or periodontal postsurgical complications, which may be attributed to apparently more open apices allowing for pulp revascularization after manipulation at the time of surgery. This report illustrates unassisted wound healing that occurs in the area of uprighting with complete reconstitution of periodontal anatomy without additional regenerative procedures to augment bone.     

Replantation of avulsed teeth with immature root development

Successful treatment of the avulsed tooth with immature root development is dependent on both pulpal and periodontal responses. The pulpal reaction is often one of revascularization with subsequent replacement of the necrotic pulp tissue. Continued root development and further calcification of the existing root structure are often seen with revitalization. The periodontal response to avulsion is dependent on the vitality of the periodontal ligament cells on the root surface. Normal healing occurs when the vitality is maintained, while replacement resorption results when the vitality is lost. Replantation after a short extra-alveolar period appears to provide the best prognosis for long-term retention of the avulsed tooth.     

A histological and micro-CT investigation in to the effect of NGF and EGF on the periodontal,alveolar bone,root and pulpal healing of replanted molars in a rat model - a pilot study

Background

This study aims to investigate, utilising micro-computed tomography (micro-CT) and histology, whether the topical application of nerve growth factor (NGF) and/or epidermal growth factor (EGF) can enhance periodontal, alveolar bone, root and pulpal tissue regeneration while minimising the risk of pulpal necrosis, root resorption and ankylosis of replanted molars in a rat model.

Methods

Twelve four-week-old male Sprague-Dawley rats were divided into four groups: sham, collagen, EGF and NGF. The maxillary right first molar was elevated and replanted with or without a collagen membrane impregnated with either the growth factors EGF or NGF, or a saline solution. Four weeks after replantation, the animals were sacrificed and the posterior maxilla was assessed using histological and micro-CT analysis. The maxillary left first molar served as the control for the corresponding right first molar.

Results

Micro-CT analysis revealed a tendency for all replanted molars to have reduced root length, root volume, alveolar bone height and inter-radicular alveolar bone volume. It appears that the use of the collagen membrane had a negative effect while no positive effect was noted with the incorporation of EGF or NGF. Histologically, the incorporation of the collagen membrane was found to negatively affect pulpal, root, periodontal and alveolar bone healing with pulpal inflammation and hard tissue formation, extensive root resorption and alveolar bone fragmentation. The incorporation of EGF and NGF did not improve root, periodontal or alveolar bone healing. However, EGF was found to improve pulp vascularisation while NGF-improved pulpal architecture and cell organisation, although not to the level of the control group.

Conclusions

Results indicate a possible benefit on pulpal vascularisation and pulpal cell organisation following the incorporation of EGF and NGF, respectively, into the alveolar socket of replanted molars in the rat model. No potential benefit of EGF and NGF was detected in periodontal or root healing, while the use of a collagen membrane carrier was found to have a negative effect on the healing response.