International Journal of Technology Assessment in Health Care, Feb 1, 1990
A more conservative approach to the treatment of traumatic dental injuries has been made possible... more A more conservative approach to the treatment of traumatic dental injuries has been made possible by knowledge concerning the pathogenesis of external root resorption, increased knowledge about wound healing processes in the pulp and periodontium, as well as by advances in restorative dentistry (reattachment of crown fragments with a dentin bonding system, the use of adhesive bridges, and advances in autotransplantation and implantation). However, a rethinking by the public, clinicians, and third-party payers is necessary for these procedures to gain wider acceptance. The present article describes the state of the art of treating dental trauma in the hope that these advances can become an accepted part of the dental trauma armamentarium and not merely scientific curiosities.
The aim of the study was to evaluate the survival of intruded permanent teeth related to treatmen... more The aim of the study was to evaluate the survival of intruded permanent teeth related to treatment in a large number of patients, with special focus on development of pulp necrosis and replacement resorption (ankylosis-related resorption). The material consisted of 168 patients (mean age 9.6 years) with 230 intruded permanent teeth from dental trauma clinics in Copenhagen, Denmark, Stockholm, Sweden, and Oslo, Norway. The degree of intrusion was classified as mild (1-<3 mm), moderate (3-7 mm), and severe (>7 mm). Root development was categorized with respect to root formation and development of the apex into three groups of increasing tooth maturity: very immature, immature, and mature. Awaiting re-eruption was the treatment of choice in 107 teeth (47%), orthodontic repositioning in 28 (12%) and surgical repositioning in 95 (41%) teeth. Pulp necrosis was diagnosed in 173 teeth (75%), infection-related root resorption in 57 (25%) and replacement resorption in 50 teeth (22%). Very immature teeth, teeth diagnosed with mild intrusion, and teeth awaiting re-eruption had significantly (P < 0.05) fewer complications. In a stepwise discriminant function analysis, choice of treatment, root development, and degree of intrusion were significantly (P < 0.05) associated with the development of replacement resorption. Root development and degree of intrusion were significantly (P < 0.05) associated with the development of pulp necrosis. This study indicates that root development and degree of intrusion may be important for the development of pulp necrosis as well as replacement resorption, whereas choice of treatment only seems to influence the development of replacement resorption in intruded permanent teeth. Awaiting re-eruption resulted in the lowest risk for developing replacement resorption.
To analyse the type and extent of injuries presented by patients seeking treatment for traumatic ... more To analyse the type and extent of injuries presented by patients seeking treatment for traumatic dental injuries at a major trauma centre. Furthermore, to analyse acute and subsequent treatment demands and treatment costs. A therapeutic and economic analysis was performed of 7549 patients treated for traumatic dental injuries in a major trauma centre located at the University Hospital in Copenhagen, Denmark. Cases were divided into uncomplicated (concussion, subluxation, enamel and enamel-dentine fractures) and complicated cases (crown fractures with exposed pulps and crown-root fractures, luxation injuries with displacement of the tooth and bone fractures). Primary tooth injuries were found in 2874 patients, involving 5443 teeth, among which 62.8% had complicated injuries. Permanent tooth injuries were found in 4525 patients, involving 10,673 teeth, among which 40.4% had complicated injuries. The cost of treatment (including acute trauma service, follow-up and subsequent restoration) was estimated to be 0.6-1 mill USD a year for the patients treated in this trauma centre. If this figure is transferred to the estimated trauma population in Denmark, a yearly cost of traumatic dental injuries appears to range from 2 to 5 mill USD per 1 mill inhabitants per year according to the treatment scenario. Thus, treatment of traumatic dental injuries comprises an expensive part of the health services in Denmark.
To analyze the risk of pulp canal obliteration (PCO), pulp necrosis (PN), repair-related resorpti... more To analyze the risk of pulp canal obliteration (PCO), pulp necrosis (PN), repair-related resorption (RRR), infection-related resorption (IRR), ankylosis-related resorption (ARR), marginal bone loss (MBL), and tooth loss (TL) for teeth involved in an alveolar process fracture and to identify possible risk factors. A total of 91 patients with 223 traumatized teeth. The risks of PCO, PN, RRR, IRR, ARR, MBL, and TL were analyzed separately for teeth with immature and mature root development using Kaplan-Meier and Aalen-Johansen methods. Possible risk factors for PN (age, fracture in relation to apex, displacement, gingival injury, degree of repositioning, type of splint, duration of splinting, treatment delay, and antibiotics) were analyzed for mature teeth using Cox regression. The level of significance was 5%. Immature: No severe complications (PN, IRR, ARR, MBL, or TL) were diagnosed during follow up. Mature: Estimated risk after a 10-year follow up: PN: 56% (95% confidence interval (CI): 48.1-63.9), IRR: 2.5% (95% CI: 0-5.1), ARR: 2.1% (95% CI: 0.1-4.1), MBL: 2.4% (95% CI: 0.3-4.4), and TL: 7.8% (95% CI: 0-15.7). The following factors significantly increased the risk of PN in teeth with mature root development: fracture in relation to apex (hazard ratio (HR): 2.6 (95% CI: 0.2 - 5.7), P = 0.01), displacement in the horizontal part of the fracture >2 mm (HR: 1.8; 95% CI: 1.1-3.2, P = 0.03), incomplete repositioning (HR: 2.1 (95% CI: 1.3-3.5), P = 0.003), and age >30 years (HR: 2.3 (95% CI: 1.1-4.6), P = 0.02). The type of splint (rigid or flexible), the duration of splinting (more or less than 4 weeks), and the administration of antibiotics did not affect the risk of PN. Teeth involved in alveolar process fractures appear, apart from PN, to have a good prognosis. A conservative treatment approach is recommended.
This study was designed to determine if avulsed per- manent incisors which have been kept dry for... more This study was designed to determine if avulsed per- manent incisors which have been kept dry for a period and then immersed in an isotonic solution prior to implantation have an increased healing rate. The per- manent maxillary incisors of six beagle dogs were grouped by lot in six treatment classes so that each type of incisor was included in
The epidemiology of traumatic dental injuries to primary and permanent teeth was studied in a Dan... more The epidemiology of traumatic dental injuries to primary and permanent teeth was studied in a Danish population sample consisting of 487 children. 30 % of the children had sustained injuries to primary teeth, whereas 22 % had injured permanent teeth. 46 % of the children had a ...
International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children, 2000
The aim of the present study was to investigate pulp healing responses following crown fracture w... more The aim of the present study was to investigate pulp healing responses following crown fracture with and without pulp exposure as well as with and without associated luxation injury and in relation to stage of root development. PATIENT MATERIAL AND METHODS: The long-term prognosis was examined for 455 permanent teeth with crown fractures, 352 (246 with associated luxation injury) without pulpal involvement and 103 (69 with associated luxation injury) with pulp exposures. Initial treatment for all patients was provided by on-call oral surgeons at the emergency service, University Hospital (Rigshospitalet), Copenhagen. In fractures without pulpal involvement, dentin was covered by a hard-setting calcium hydroxide cement (Dycal), marginal enamel acid-etched (phosphoric acid gel), then covered with a temporary crown and bridge material. In the case of pulp exposure, pulp capping or partial pulpotomy was performed. Thereafter treatment was identical to the first group. Patients were then...
The roots of two incisors were treated by apicoectomy and a retrograde dentin-bonded composite fi... more The roots of two incisors were treated by apicoectomy and a retrograde dentin-bonded composite filling. Periapical healing was observed a few months later by radiography. Later, due to root fracture and marginal bone resorption, the apical parts were removed including adjacent periapical bone. A histological and scanning electron microscopic examination of the tissue showed reformation of periodontium adjacent to the composite, including reformation of a lamina dura, inserting Sharpey's fibers and cementum deposited in intimate contact with the composite. This finding is in agreement with previous observations of tissue surrounding retrograde dentin-bonded composite fillings placed in monkeys, indicating that tissue regeneration including cementogenesis may occur on composite material and consequently form a biological closure of the root canal.
Journal of Endodontics, Volume 8, Issue 9, Pages 391-397, September 1982, Authors:Miomir Cvek, DM... more Journal of Endodontics, Volume 8, Issue 9, Pages 391-397, September 1982, Authors:Miomir Cvek, DMS, PhD; Peter E. Cleaton-Jones, BDS, PhD; John C. Austin, 8VSc; Jens O. Andreasen, DDS.
International Journal of Paediatric Dentistry, 2001
To analyse the type and extent of injuries presented by patients seeking treatment for traumatic ... more To analyse the type and extent of injuries presented by patients seeking treatment for traumatic dental injuries at a major trauma centre. Furthermore, to analyse acute and subsequent treatment demands and treatment costs. A therapeutic and economic analysis was performed of 7549 patients treated for traumatic dental injuries in a major trauma centre located at the University Hospital in Copenhagen, Denmark. Cases were divided into uncomplicated (concussion, subluxation, enamel and enamel-dentine fractures) and complicated cases (crown fractures with exposed pulps and crown-root fractures, luxation injuries with displacement of the tooth and bone fractures). Primary tooth injuries were found in 2874 patients, involving 5443 teeth, among which 62.8% had complicated injuries. Permanent tooth injuries were found in 4525 patients, involving 10,673 teeth, among which 40.4% had complicated injuries. The cost of treatment (including acute trauma service, follow-up and subsequent restoration) was estimated to be 0.6-1 mill USD a year for the patients treated in this trauma centre. If this figure is transferred to the estimated trauma population in Denmark, a yearly cost of traumatic dental injuries appears to range from 2 to 5 mill USD per 1 mill inhabitants per year according to the treatment scenario. Thus, treatment of traumatic dental injuries comprises an expensive part of the health services in Denmark.
International Journal of Paediatric Dentistry, 2007
The aim of this study was to classify early arrested eruption of primary molars and to analyse an... more The aim of this study was to classify early arrested eruption of primary molars and to analyse and explain the sequelae for the surrounding alveolar bone and the succeeding premolar. The position of the arrested primary molars in the mandible, the height of the local alveolar bone, and the morphology and location of the succeeding premolar were evaluated on radiographs from 29 children. Four groups of arrest from mild to severe with regards to infra-position were categorized (Groups I-IV). Mean ages at the time of referral decreased from Groups I (8 years, 10 months) to Group IV (5 years, 9 months). SEQUELAE: (i) Reduction of alveolar bone height (Groups I-III); (ii) delayed maturity of the succeeding premolar (two-thirds of the cases); (iii) malformation of the succeeding premolar (mainly Groups III and IV); and (iv) ectopically located premolar occlusal to the retained molar (Group IV). The deeper in the alveolar process a primary molar is retained, the earlier the disturbance in the eruption has occurred, and the greater is the risk of the permanent tooth germ being malformed and malpositioned. It is estimated that the earliest occurrences of arrested eruption of primary molars supposedly occur before the age of 3.
Cementoblast loss and root resorption on the root surface was registered histologically after rem... more Cementoblast loss and root resorption on the root surface was registered histologically after removal and immediate replantation of maxillary central incisors in monkeys (Cecropithecus aethiops). Incisors were removed with either a conventional extraction technique using forceps or with a special designed extrusion instrument and in both cases teeth were immediately replanted. Altogether 18 monkeys were used for the experiments in which 9 monkeys were sacrificed after 3 d and 9 animals after 8 wk. Histological analysis was made in horizontal sections perpendicular to the long axis of the tooth using either 24 measuring points or 12 sections. Histometric analysis showed extensive cementoblast loss in the periodontal ligament (PDL) and with a maximum of damage occurring on the corner surfaces of the root. Extracted teeth showed significantly more extensive cementoblast loss than extruded teeth. Root resorption was also found in the corner locations and was significantly more frequent in extracted than in extruded teeth. There was a similarity in the distribution of cementoblast loss and root resorption indicating that root resorption develops in the same areas where cementoblast loss takes place, i.e. locations that are more compressed during removal of the tooth and must have caused by mechanical damage to the PDL exerted on the root surface during tooth removal.
This study examined the effect of various zinc oxide materials as root-end fillings of teeth in a... more This study examined the effect of various zinc oxide materials as root-end fillings of teeth in a replantation model. A total of 35 molar teeth were used from 19 monkeys. After extraction, root ends were resected, the canals contaminated with oral bacteria, root-end cavities prepared and fillings placed prior to replantation. After 8 weeks the teeth and surrounding jaw were removed and prepared for histological examinatiorj. Twelve roots were filled with IRM plus dentine chips, and six with Cavit; the tissue response around root ends filled with these materials as assessed by inflammation was similar to that previously reported to IRM and Super EBA cement and was characterized by little or no infiammation of limited extent. In contrast, more severe infiammation was obseri'ed around root ends filled with plain zinc oxide-eugeno! or Kalzinol; however, the reaction was neither as severe nor as extensive as that to amalgam root-end fillings. Giant cells were obseri'ed most often on the surface of fillings with Cavit and zinc oxide-eugenol. It is concluded that the tissue response to IRM with or without added dentine. Super EBA and Cavit was similar and mild; it was less severe than that to zinc oxide-eugenol and Kalzinol, AU these materials had a much more favourable response than amalgam.
Calcium hydroxide [Ca(OH) 2 ], when used as a root canal dressing, has been shown to promote peri... more Calcium hydroxide [Ca(OH) 2 ], when used as a root canal dressing, has been shown to promote periapical healing, induce formation of an apical hard tissue barrier (apexification), and arrest infection-related root resorption. The main mechanism of action is thought to be the high alkalinity of Ca(OH) 2 ensuring a bactericidal or bacteriostatic effect upon microorganisms in the root canal and dentinal tubules. Several anatomical factors related to the root canal, such as the coronal access cavity, the apical foramen, the dentinal tubules, and existing resorption cavities on the root surface, all allow leakage of hydroxide ions from the root canal. The purpose of the present clinical study was to analyze pH changes in 63 permanent anterior teeth in which Ca(OH) 2 (Calasept s ) was used as an initial canal dressing after replantation and subsequent pulp necrosis had developed. The pH changes in the pulp canal were studied with relation to observation period, stage of root formation, healing of any periapical radiolucency, infection-related root resorption, formation of an apical hard tissue barrier, and finally the radiographic appearance of Ca(OH) 2 in the canal (i.e. present or not). The study showed that several factors determined the pH level: the observation period (i.e. observation periods exceeding 6 months showed a significant drop in pH level below a pH of 10), an initial active inflammatory root resorption (tendency to be related to a drop in pH), and a subsequent progression of infection-related resorption (the same tendency to be related to a drop in pH to below 10). The size of the apical foramen and the length of the pulp had no relation to pH change. The radiographic disappearance of Ca(OH) 2 in the root canal (loss of radiopacity of the canal dressing) was found to be significantly associated with a drop in pH (P 5 0.001). It was concluded that radiographic monitoring of the Ca(OH) 2 presence in the root canal is essential for endodontic treatment planning (i.e. when to replace Ca(OH) 2 or perform a permanent root filling). Furthermore, continuous activity of inflammatory root resorption may indicate a drop in pH and should result in replacement of new Ca(OH) 2 . It should be noted that these findings apply to a Ca(OH) 2 product (Calasept s ) with no added radiopaque material.
Decoronation of ankylosed teeth in infraposition was introduced in 1984 by Malmgren and co-worker... more Decoronation of ankylosed teeth in infraposition was introduced in 1984 by Malmgren and co-workers (1). This method is used all over the world today. It has been clinically shown that the procedure preserves the alveolar width and rebuilds lost vertical bone of the alveolar ridge in growing individuals. The biological explanation is that the decoronated root serves as a matrix for new bone development during resorption of the root and that the lost vertical alveolar bone is rebuilt during eruption of adjacent teeth. First a new periosteum is formed over the decoronated root, allowing vertical alveolar growth. Then the interdental fibers that have been severed by the decoronation procedure are reorganized between adjacent teeth. The continued eruption of these teeth mediates marginal bone apposition via the dental-periosteal fiber complex. The erupting teeth are linked with the periosteum covering the top of the alveolar socket and indirectly via the alveolar gingival fibers, which are inserted in the alveolar crest and in the lamina propria of the interdental papilla. Both structures can generate a traction force resulting in bone apposition on top of the alveolar crest. This theoretical biological explanation is based on known anatomical features, known eruption processes and clinical observations.
Traumatic dental injuries are for the most part unanticipated events that, if not managed appropr... more Traumatic dental injuries are for the most part unanticipated events that, if not managed appropriately, can have serious consequences for the patient. The purpose of this review is to describe the current concepts in establishing diagnosis descriptive of specific traumatic entities, and to delineate recommended treatment approaches for these injuries based on available evidence.
Traumatic dental injuries result in tissue damage and risk of infection. Experimental studies hav... more Traumatic dental injuries result in tissue damage and risk of infection. Experimental studies have shown various avenues for bacterial invasion following trauma: enamel infractions, dentinal tubules, exposed pulps, damaged periodontal ligament (PDL) and exposed alveolar bone. Hematogenous seeding of bacteria (anachoresis) may also occur during pulpal revascularization after trauma. The implication of these routes of entry differs according to the type of traumatic dental injury. It is known that bacterial colonization in a wound may protract or even arrest healing. Hence, it might be of interest to examine the possibility of protecting the healing events by the use of antibiotics after dental and maxillofacial trauma. A survey of the literature revealed a series of studies using an extraction/replantation model in monkeys and dogs. In periodontal ligament healing, these studies showed that systemically administered antibiotics (penicillin, streptomycin, amoxicillin and tetracycline) or topically applied antibiotics either on the root surface or in the root canal in general had the effect of preventing or reducing the extent of infection-related resorption. With respect to pulpal healing, systemically administered antibiotics had no effect upon pulp healing whereas topically administered tetracycline (5 min storage in a tetracycline solution or the use of tetracycline powder) doubled the chance of pulp revascularization. To date, there has been only one nonrandomized clinical replantation study which showed that systemically applied penicillin did not reduce root resorption or the chance of pulp revascularization. In experimental studies, the topical use of tetracycline appeared to significantly improve the chance of revascularization of the pulp after replantation. In other dental trauma types, only a few clinical studies were available concerning the role of antibiotics and none of them were randomized. No positive effect of antibiotics has been reported on pulpal healing in cases of luxation injury or root fracture. Regarding PDL healing, a possible negative effect of antibiotics was indicated for lateral luxations; however, confounding factors might exist. In the case of mandibular fractures with communication to the oral cavity, five randomized studies were found, all indicating that antibiotics significantly reduced the risk of fracture line infection. Randomized clinical studies on the effect of systemic and topical use of antibiotics for traumatic dental injuries are very much needed.
International Journal of Technology Assessment in Health Care, Feb 1, 1990
A more conservative approach to the treatment of traumatic dental injuries has been made possible... more A more conservative approach to the treatment of traumatic dental injuries has been made possible by knowledge concerning the pathogenesis of external root resorption, increased knowledge about wound healing processes in the pulp and periodontium, as well as by advances in restorative dentistry (reattachment of crown fragments with a dentin bonding system, the use of adhesive bridges, and advances in autotransplantation and implantation). However, a rethinking by the public, clinicians, and third-party payers is necessary for these procedures to gain wider acceptance. The present article describes the state of the art of treating dental trauma in the hope that these advances can become an accepted part of the dental trauma armamentarium and not merely scientific curiosities.
The aim of the study was to evaluate the survival of intruded permanent teeth related to treatmen... more The aim of the study was to evaluate the survival of intruded permanent teeth related to treatment in a large number of patients, with special focus on development of pulp necrosis and replacement resorption (ankylosis-related resorption). The material consisted of 168 patients (mean age 9.6 years) with 230 intruded permanent teeth from dental trauma clinics in Copenhagen, Denmark, Stockholm, Sweden, and Oslo, Norway. The degree of intrusion was classified as mild (1-<3 mm), moderate (3-7 mm), and severe (>7 mm). Root development was categorized with respect to root formation and development of the apex into three groups of increasing tooth maturity: very immature, immature, and mature. Awaiting re-eruption was the treatment of choice in 107 teeth (47%), orthodontic repositioning in 28 (12%) and surgical repositioning in 95 (41%) teeth. Pulp necrosis was diagnosed in 173 teeth (75%), infection-related root resorption in 57 (25%) and replacement resorption in 50 teeth (22%). Very immature teeth, teeth diagnosed with mild intrusion, and teeth awaiting re-eruption had significantly (P < 0.05) fewer complications. In a stepwise discriminant function analysis, choice of treatment, root development, and degree of intrusion were significantly (P < 0.05) associated with the development of replacement resorption. Root development and degree of intrusion were significantly (P < 0.05) associated with the development of pulp necrosis. This study indicates that root development and degree of intrusion may be important for the development of pulp necrosis as well as replacement resorption, whereas choice of treatment only seems to influence the development of replacement resorption in intruded permanent teeth. Awaiting re-eruption resulted in the lowest risk for developing replacement resorption.
To analyse the type and extent of injuries presented by patients seeking treatment for traumatic ... more To analyse the type and extent of injuries presented by patients seeking treatment for traumatic dental injuries at a major trauma centre. Furthermore, to analyse acute and subsequent treatment demands and treatment costs. A therapeutic and economic analysis was performed of 7549 patients treated for traumatic dental injuries in a major trauma centre located at the University Hospital in Copenhagen, Denmark. Cases were divided into uncomplicated (concussion, subluxation, enamel and enamel-dentine fractures) and complicated cases (crown fractures with exposed pulps and crown-root fractures, luxation injuries with displacement of the tooth and bone fractures). Primary tooth injuries were found in 2874 patients, involving 5443 teeth, among which 62.8% had complicated injuries. Permanent tooth injuries were found in 4525 patients, involving 10,673 teeth, among which 40.4% had complicated injuries. The cost of treatment (including acute trauma service, follow-up and subsequent restoration) was estimated to be 0.6-1 mill USD a year for the patients treated in this trauma centre. If this figure is transferred to the estimated trauma population in Denmark, a yearly cost of traumatic dental injuries appears to range from 2 to 5 mill USD per 1 mill inhabitants per year according to the treatment scenario. Thus, treatment of traumatic dental injuries comprises an expensive part of the health services in Denmark.
To analyze the risk of pulp canal obliteration (PCO), pulp necrosis (PN), repair-related resorpti... more To analyze the risk of pulp canal obliteration (PCO), pulp necrosis (PN), repair-related resorption (RRR), infection-related resorption (IRR), ankylosis-related resorption (ARR), marginal bone loss (MBL), and tooth loss (TL) for teeth involved in an alveolar process fracture and to identify possible risk factors. A total of 91 patients with 223 traumatized teeth. The risks of PCO, PN, RRR, IRR, ARR, MBL, and TL were analyzed separately for teeth with immature and mature root development using Kaplan-Meier and Aalen-Johansen methods. Possible risk factors for PN (age, fracture in relation to apex, displacement, gingival injury, degree of repositioning, type of splint, duration of splinting, treatment delay, and antibiotics) were analyzed for mature teeth using Cox regression. The level of significance was 5%. Immature: No severe complications (PN, IRR, ARR, MBL, or TL) were diagnosed during follow up. Mature: Estimated risk after a 10-year follow up: PN: 56% (95% confidence interval (CI): 48.1-63.9), IRR: 2.5% (95% CI: 0-5.1), ARR: 2.1% (95% CI: 0.1-4.1), MBL: 2.4% (95% CI: 0.3-4.4), and TL: 7.8% (95% CI: 0-15.7). The following factors significantly increased the risk of PN in teeth with mature root development: fracture in relation to apex (hazard ratio (HR): 2.6 (95% CI: 0.2 - 5.7), P = 0.01), displacement in the horizontal part of the fracture >2 mm (HR: 1.8; 95% CI: 1.1-3.2, P = 0.03), incomplete repositioning (HR: 2.1 (95% CI: 1.3-3.5), P = 0.003), and age >30 years (HR: 2.3 (95% CI: 1.1-4.6), P = 0.02). The type of splint (rigid or flexible), the duration of splinting (more or less than 4 weeks), and the administration of antibiotics did not affect the risk of PN. Teeth involved in alveolar process fractures appear, apart from PN, to have a good prognosis. A conservative treatment approach is recommended.
This study was designed to determine if avulsed per- manent incisors which have been kept dry for... more This study was designed to determine if avulsed per- manent incisors which have been kept dry for a period and then immersed in an isotonic solution prior to implantation have an increased healing rate. The per- manent maxillary incisors of six beagle dogs were grouped by lot in six treatment classes so that each type of incisor was included in
The epidemiology of traumatic dental injuries to primary and permanent teeth was studied in a Dan... more The epidemiology of traumatic dental injuries to primary and permanent teeth was studied in a Danish population sample consisting of 487 children. 30 % of the children had sustained injuries to primary teeth, whereas 22 % had injured permanent teeth. 46 % of the children had a ...
International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children, 2000
The aim of the present study was to investigate pulp healing responses following crown fracture w... more The aim of the present study was to investigate pulp healing responses following crown fracture with and without pulp exposure as well as with and without associated luxation injury and in relation to stage of root development. PATIENT MATERIAL AND METHODS: The long-term prognosis was examined for 455 permanent teeth with crown fractures, 352 (246 with associated luxation injury) without pulpal involvement and 103 (69 with associated luxation injury) with pulp exposures. Initial treatment for all patients was provided by on-call oral surgeons at the emergency service, University Hospital (Rigshospitalet), Copenhagen. In fractures without pulpal involvement, dentin was covered by a hard-setting calcium hydroxide cement (Dycal), marginal enamel acid-etched (phosphoric acid gel), then covered with a temporary crown and bridge material. In the case of pulp exposure, pulp capping or partial pulpotomy was performed. Thereafter treatment was identical to the first group. Patients were then...
The roots of two incisors were treated by apicoectomy and a retrograde dentin-bonded composite fi... more The roots of two incisors were treated by apicoectomy and a retrograde dentin-bonded composite filling. Periapical healing was observed a few months later by radiography. Later, due to root fracture and marginal bone resorption, the apical parts were removed including adjacent periapical bone. A histological and scanning electron microscopic examination of the tissue showed reformation of periodontium adjacent to the composite, including reformation of a lamina dura, inserting Sharpey's fibers and cementum deposited in intimate contact with the composite. This finding is in agreement with previous observations of tissue surrounding retrograde dentin-bonded composite fillings placed in monkeys, indicating that tissue regeneration including cementogenesis may occur on composite material and consequently form a biological closure of the root canal.
Journal of Endodontics, Volume 8, Issue 9, Pages 391-397, September 1982, Authors:Miomir Cvek, DM... more Journal of Endodontics, Volume 8, Issue 9, Pages 391-397, September 1982, Authors:Miomir Cvek, DMS, PhD; Peter E. Cleaton-Jones, BDS, PhD; John C. Austin, 8VSc; Jens O. Andreasen, DDS.
International Journal of Paediatric Dentistry, 2001
To analyse the type and extent of injuries presented by patients seeking treatment for traumatic ... more To analyse the type and extent of injuries presented by patients seeking treatment for traumatic dental injuries at a major trauma centre. Furthermore, to analyse acute and subsequent treatment demands and treatment costs. A therapeutic and economic analysis was performed of 7549 patients treated for traumatic dental injuries in a major trauma centre located at the University Hospital in Copenhagen, Denmark. Cases were divided into uncomplicated (concussion, subluxation, enamel and enamel-dentine fractures) and complicated cases (crown fractures with exposed pulps and crown-root fractures, luxation injuries with displacement of the tooth and bone fractures). Primary tooth injuries were found in 2874 patients, involving 5443 teeth, among which 62.8% had complicated injuries. Permanent tooth injuries were found in 4525 patients, involving 10,673 teeth, among which 40.4% had complicated injuries. The cost of treatment (including acute trauma service, follow-up and subsequent restoration) was estimated to be 0.6-1 mill USD a year for the patients treated in this trauma centre. If this figure is transferred to the estimated trauma population in Denmark, a yearly cost of traumatic dental injuries appears to range from 2 to 5 mill USD per 1 mill inhabitants per year according to the treatment scenario. Thus, treatment of traumatic dental injuries comprises an expensive part of the health services in Denmark.
International Journal of Paediatric Dentistry, 2007
The aim of this study was to classify early arrested eruption of primary molars and to analyse an... more The aim of this study was to classify early arrested eruption of primary molars and to analyse and explain the sequelae for the surrounding alveolar bone and the succeeding premolar. The position of the arrested primary molars in the mandible, the height of the local alveolar bone, and the morphology and location of the succeeding premolar were evaluated on radiographs from 29 children. Four groups of arrest from mild to severe with regards to infra-position were categorized (Groups I-IV). Mean ages at the time of referral decreased from Groups I (8 years, 10 months) to Group IV (5 years, 9 months). SEQUELAE: (i) Reduction of alveolar bone height (Groups I-III); (ii) delayed maturity of the succeeding premolar (two-thirds of the cases); (iii) malformation of the succeeding premolar (mainly Groups III and IV); and (iv) ectopically located premolar occlusal to the retained molar (Group IV). The deeper in the alveolar process a primary molar is retained, the earlier the disturbance in the eruption has occurred, and the greater is the risk of the permanent tooth germ being malformed and malpositioned. It is estimated that the earliest occurrences of arrested eruption of primary molars supposedly occur before the age of 3.
Cementoblast loss and root resorption on the root surface was registered histologically after rem... more Cementoblast loss and root resorption on the root surface was registered histologically after removal and immediate replantation of maxillary central incisors in monkeys (Cecropithecus aethiops). Incisors were removed with either a conventional extraction technique using forceps or with a special designed extrusion instrument and in both cases teeth were immediately replanted. Altogether 18 monkeys were used for the experiments in which 9 monkeys were sacrificed after 3 d and 9 animals after 8 wk. Histological analysis was made in horizontal sections perpendicular to the long axis of the tooth using either 24 measuring points or 12 sections. Histometric analysis showed extensive cementoblast loss in the periodontal ligament (PDL) and with a maximum of damage occurring on the corner surfaces of the root. Extracted teeth showed significantly more extensive cementoblast loss than extruded teeth. Root resorption was also found in the corner locations and was significantly more frequent in extracted than in extruded teeth. There was a similarity in the distribution of cementoblast loss and root resorption indicating that root resorption develops in the same areas where cementoblast loss takes place, i.e. locations that are more compressed during removal of the tooth and must have caused by mechanical damage to the PDL exerted on the root surface during tooth removal.
This study examined the effect of various zinc oxide materials as root-end fillings of teeth in a... more This study examined the effect of various zinc oxide materials as root-end fillings of teeth in a replantation model. A total of 35 molar teeth were used from 19 monkeys. After extraction, root ends were resected, the canals contaminated with oral bacteria, root-end cavities prepared and fillings placed prior to replantation. After 8 weeks the teeth and surrounding jaw were removed and prepared for histological examinatiorj. Twelve roots were filled with IRM plus dentine chips, and six with Cavit; the tissue response around root ends filled with these materials as assessed by inflammation was similar to that previously reported to IRM and Super EBA cement and was characterized by little or no infiammation of limited extent. In contrast, more severe infiammation was obseri'ed around root ends filled with plain zinc oxide-eugeno! or Kalzinol; however, the reaction was neither as severe nor as extensive as that to amalgam root-end fillings. Giant cells were obseri'ed most often on the surface of fillings with Cavit and zinc oxide-eugenol. It is concluded that the tissue response to IRM with or without added dentine. Super EBA and Cavit was similar and mild; it was less severe than that to zinc oxide-eugenol and Kalzinol, AU these materials had a much more favourable response than amalgam.
Calcium hydroxide [Ca(OH) 2 ], when used as a root canal dressing, has been shown to promote peri... more Calcium hydroxide [Ca(OH) 2 ], when used as a root canal dressing, has been shown to promote periapical healing, induce formation of an apical hard tissue barrier (apexification), and arrest infection-related root resorption. The main mechanism of action is thought to be the high alkalinity of Ca(OH) 2 ensuring a bactericidal or bacteriostatic effect upon microorganisms in the root canal and dentinal tubules. Several anatomical factors related to the root canal, such as the coronal access cavity, the apical foramen, the dentinal tubules, and existing resorption cavities on the root surface, all allow leakage of hydroxide ions from the root canal. The purpose of the present clinical study was to analyze pH changes in 63 permanent anterior teeth in which Ca(OH) 2 (Calasept s ) was used as an initial canal dressing after replantation and subsequent pulp necrosis had developed. The pH changes in the pulp canal were studied with relation to observation period, stage of root formation, healing of any periapical radiolucency, infection-related root resorption, formation of an apical hard tissue barrier, and finally the radiographic appearance of Ca(OH) 2 in the canal (i.e. present or not). The study showed that several factors determined the pH level: the observation period (i.e. observation periods exceeding 6 months showed a significant drop in pH level below a pH of 10), an initial active inflammatory root resorption (tendency to be related to a drop in pH), and a subsequent progression of infection-related resorption (the same tendency to be related to a drop in pH to below 10). The size of the apical foramen and the length of the pulp had no relation to pH change. The radiographic disappearance of Ca(OH) 2 in the root canal (loss of radiopacity of the canal dressing) was found to be significantly associated with a drop in pH (P 5 0.001). It was concluded that radiographic monitoring of the Ca(OH) 2 presence in the root canal is essential for endodontic treatment planning (i.e. when to replace Ca(OH) 2 or perform a permanent root filling). Furthermore, continuous activity of inflammatory root resorption may indicate a drop in pH and should result in replacement of new Ca(OH) 2 . It should be noted that these findings apply to a Ca(OH) 2 product (Calasept s ) with no added radiopaque material.
Decoronation of ankylosed teeth in infraposition was introduced in 1984 by Malmgren and co-worker... more Decoronation of ankylosed teeth in infraposition was introduced in 1984 by Malmgren and co-workers (1). This method is used all over the world today. It has been clinically shown that the procedure preserves the alveolar width and rebuilds lost vertical bone of the alveolar ridge in growing individuals. The biological explanation is that the decoronated root serves as a matrix for new bone development during resorption of the root and that the lost vertical alveolar bone is rebuilt during eruption of adjacent teeth. First a new periosteum is formed over the decoronated root, allowing vertical alveolar growth. Then the interdental fibers that have been severed by the decoronation procedure are reorganized between adjacent teeth. The continued eruption of these teeth mediates marginal bone apposition via the dental-periosteal fiber complex. The erupting teeth are linked with the periosteum covering the top of the alveolar socket and indirectly via the alveolar gingival fibers, which are inserted in the alveolar crest and in the lamina propria of the interdental papilla. Both structures can generate a traction force resulting in bone apposition on top of the alveolar crest. This theoretical biological explanation is based on known anatomical features, known eruption processes and clinical observations.
Traumatic dental injuries are for the most part unanticipated events that, if not managed appropr... more Traumatic dental injuries are for the most part unanticipated events that, if not managed appropriately, can have serious consequences for the patient. The purpose of this review is to describe the current concepts in establishing diagnosis descriptive of specific traumatic entities, and to delineate recommended treatment approaches for these injuries based on available evidence.
Traumatic dental injuries result in tissue damage and risk of infection. Experimental studies hav... more Traumatic dental injuries result in tissue damage and risk of infection. Experimental studies have shown various avenues for bacterial invasion following trauma: enamel infractions, dentinal tubules, exposed pulps, damaged periodontal ligament (PDL) and exposed alveolar bone. Hematogenous seeding of bacteria (anachoresis) may also occur during pulpal revascularization after trauma. The implication of these routes of entry differs according to the type of traumatic dental injury. It is known that bacterial colonization in a wound may protract or even arrest healing. Hence, it might be of interest to examine the possibility of protecting the healing events by the use of antibiotics after dental and maxillofacial trauma. A survey of the literature revealed a series of studies using an extraction/replantation model in monkeys and dogs. In periodontal ligament healing, these studies showed that systemically administered antibiotics (penicillin, streptomycin, amoxicillin and tetracycline) or topically applied antibiotics either on the root surface or in the root canal in general had the effect of preventing or reducing the extent of infection-related resorption. With respect to pulpal healing, systemically administered antibiotics had no effect upon pulp healing whereas topically administered tetracycline (5 min storage in a tetracycline solution or the use of tetracycline powder) doubled the chance of pulp revascularization. To date, there has been only one nonrandomized clinical replantation study which showed that systemically applied penicillin did not reduce root resorption or the chance of pulp revascularization. In experimental studies, the topical use of tetracycline appeared to significantly improve the chance of revascularization of the pulp after replantation. In other dental trauma types, only a few clinical studies were available concerning the role of antibiotics and none of them were randomized. No positive effect of antibiotics has been reported on pulpal healing in cases of luxation injury or root fracture. Regarding PDL healing, a possible negative effect of antibiotics was indicated for lateral luxations; however, confounding factors might exist. In the case of mandibular fractures with communication to the oral cavity, five randomized studies were found, all indicating that antibiotics significantly reduced the risk of fracture line infection. Randomized clinical studies on the effect of systemic and topical use of antibiotics for traumatic dental injuries are very much needed.
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