Showing papers in "Dental Traumatology in 2002"

Long-term calcium hydroxide as a root canal dressing may increase risk of root fracture.

Abstract: It has been proposed (Cvek 1992) that immature teeth are weakened by filling of the root canals with calcium hydroxide dressing and gutta-percha. The aim of the present study was to test the hypothesis that dentin in contact with calcium hydroxide would show a reduction in fracture strength after a certain period of time. Immature mandibular incisors from sheep were extracted and divided into two experimental groups. Group 1: the pulps were extirpated via the apical foramen. The root canals were then filled with calcium hydroxide (Calasept) and sealed with IRM(R) cement, and the teeth were then stored in saline at room temperature for 0.5, 1, 2, 3, 6, 9, or 12 months. Group 2: the pulps were extirpated and the root canals were filled with saline and sealed with IRM(R) cement. The teeth were then stored in saline for 2 months. Intact teeth served as controls and were tested immediately after extraction. All teeth were tested for fracture strength in an Instron testing machine at the indicated observation periods. The results showed a markedly decrease in fracture strength with increasing storage time for group 1 (calcium hydroxide dressing). The results indicate that the fracture strength of calcium hydroxide-filled immature teeth will be halved in about a year due to the root filling. The finding may explain the frequent reported fractures of immature teeth filled with calcium hydroxide for extended periods.

Autotransplantation of teeth: requirements for predictable success.

Abstract: The aim of this article is to summarize the biologic principles required for successful autotransplantation of teeth. Indications, armamentarium, technique and prognosis will be discussed.

Clinical management of the avulsed tooth: present strategies and future directions.

Abstract: The aim of this review article is to supplement the recently published International Association of Dental Traumatology (IADT) guidelines on treatment of the avulsed tooth. A thorough discussion on the reasoning behind each guideline is presented. In addition, the author's views on alternate treatment strategies and future directions, along with recent research on the subject of the avulsed tooth, are also presented.

Effect of treatment delay upon pulp and periodontal healing of traumatic dental injuries – a review article

Abstract: Based on an analysis of the literature concerning parameters influencing the prognosis of traumatic dental injuries, few studies were found to have examined possible relationships between treatment delay and pulpal and periodontal ligament healing complications. It has been commonly accepted that all injuries should be treated on an emergency basis, for the comfort of the patient and also to reduce wound healing complications. For practical and especially economic reasons, various approaches can be selected to fulfill such a demand, such as acute treatment (i.e. within a few hours), subacute (i.e. within the first 24 h), and delayed (i.e. after the first 24 h). In this survey the consequences of treatment delay on pulpal and periodontal healing have been analyzed for the various dental trauma groups. Applying such a treatment approach to the various types of injuries, the following treatment guidelines can be recommended, based on our present rather limited knowledge of the effect of treatment delay upon wound healing. Crown and crown/root fractures: Subacute or delayed approach. Root fractures: Acute or subacute approach. Alveolar fractures: Acute approach (evidence however questionable). Concussion and subluxation: Subacute approach. Extrusion and lateral luxation: Acute or subacute approach (evidence however questionable). Intrusion: Subacute approach (evidence however questionable). Avulsion: If the tooth is not replanted at the time of injury, acute approach; otherwise subacute. Primary tooth injury: Subacute approach, unless the primary tooth is displaced into the follicle of the permanent tooth or occlusal problems are present; in the latter instances, an acute approach should be chosen. These treatment guidelines are based on very limited evidence from the literature and should be revised as soon as more evidence about the effect of treatment delay becomes available.

Crown fractures in the permanent dentition: pulpal and restorative considerations.

Abstract: Crown fractures account for the highest percentage of all traumatic injuries in the permanent dentition. This review paper will discuss the different types of crown fracture, from the uncomplicated to complicated, including crown-root fractures. It will focus on two different aspects: the pulp, with an attempt to correlate epidemiological, experimental, histopathological and clinical studies, so that the clinician can better understand the underlying processes accounting for success or failure to maintain pulp vitality. Also, we will consider the restoration: knowledge about bonding to dentin and new material is evolving extremely quickly making it difficult for the clinician to keep up with the developments. If handled properly, prognosis of the pulp, after traumatic crown fracture, is good. Prognosis of the restoration has also improved considerably over the last few years, and it appears that this trend will continue in the future.

Traumatic injuries in the primary dentition.

Abstract: As a support for the guidelines published in 2001, a review of the literature was carried out using the evidence-based approach in order to update the state of the art regarding epidemiology and treatment of traumatic dental injuries in the primary dentition. An online search in Medline, and a review of expert literature, lead to the conclusion that most luxation injuries heal spontaneously, and unless more conclusive evidence is available, conservative treatment of acute dental trauma for preschool children is suggested. Pain control, the dentist's ability to cope with the child's anxiety, and follow-up instructions in oral hygiene techniques will allow many primary teeth that are currently lost at the time of injury to be saved.

Traumatized primary teeth in children assisted at the Federal University of Santa Catarina, Brazil.

Abstract: The goal of this study was to determine factors related to the occurrence of dental trauma in permanent teeth of children assisted at the Pediatric Dentistry Clinic of the Federal University of Santa Catarina (UFSC) Florianopolis, Brazil. During a period of 18 months, 36 children between 7 and 12 years of age had 72 traumatized teeth treated. The children were all assisted by one professional, a dentist working as a trainee of the Pediatric Dentistry Clinic. The occurrence of trauma was higher in male patients (61.3%) and in children between 8 and 9 years old with an average age of mean=9.4 years. In the group assisted, 63.9% of the children had more than one traumatized tooth and trauma reoccurred 19.4% of the time. The maxillary anterior teeth represented 96.1% of the cases and the central incisor teeth were the most affected. Both sides of the mouth had approximately the same number of traumas. Fractures were more frequent (51.4%) than luxations (48.6%). Enamel/dentin crown fractures represented 51.4% of the total traumatized teeth. Falls were the main cause of trauma (83.3%). A dental professional assisted 36.1% of the children in some way during the first 24 h after the incident. The study concluded that the permanent dentition is mostly affected by crown fractures that occur especially on maxillary central incisor teeth in patients between 8 and 9 years of age. The major etiological factor is falls that affected more than one tooth. Re-occurrence of trauma is fairly common.

The use of MTA in teeth with necrotic pulps and open apices.

Abstract: Three clinical cases have been treated with the use of an apical plug of MTA for apexification. All three cases were central incisors that had suffered premature interruption of root development as a consequence of trauma. According to the treatment protocol, the root canals were rinsed with 5% NaOCl; then, calcium hydroxide paste was placed in the canals for 1 week. Consequently, the apical portion of the canal (4 mm) was filled with MTA. The remaining portion of the root canals was then closed with thermoplastic gutta-percha. At 6-month and 1-year follow-up period the clinical and radiographic appearance of the teeth showed resolution of the periapical lesions. MTA appears to be a valid option for apexification with its main advantage being the speed at which the treatment can be completed.

Dental trauma and level of information: mouthguard use in different contact sports.

Abstract: The objective of the present work was to study the occurrence of dental trauma in different sports, as well as to check if athletes used mouthguard during sport activities, and knew the significance of its utilization. The professional and semi-professional athletes who practised contact sports were interviewed, and were analyzed to determine the occurrence of dental trauma during sport practice, as well as if the athletes used a mouthguard and knew its indication. Results showed a high rate of dental trauma in athletes compared to the general population. The majority of athletes also demonstrated little utilization of mouthguard, in spite of the information about usage during sports practices and a general knowledge of its uses.

EVA mouthguards: how thick should they be?

Abstract: A major consideration in the performance of mouthguards is their ability to absorb energy and reduce transmitted forces when impacted. This is especially important to participants in contact sports such as hockey or football. The thickness of mouthguard materials is directly related to energy absorption and inversely related to transmitted forces when impacted. However, wearer comfort is also an important factor in their use. Thicker mouthguards are not user-friendly. While thickness of material over incisal edges and cusps of teeth is critical, just how thick should a mouthguard be and especially in these two areas? Transmitted forces through different thicknesses of the most commonly used mouthguard material, ethylene vinyl acetate (EVA) (Shore A Hardness of 80) were compared when impacted with identical forces which were capable of damaging the oro-facial complex. The constant impact force used in the tests was produced by a pendulum and had an energy of 4.4 joules and a velocity of 3 meters per second. Improvements in energy absorption and reductions in transmitted forces were observed with increasing thickness. However, these improvements lessened when the mouthguard material thickness was greater than 4 mm. The results show that the optimal thickness for EVA mouthguard material with a Shore A Hardness of 80 is around 4 mm. Increased thickness, while improving performance marginally, results in less wearer comfort and acceptance.

Rate of infraposition of reimplanted ankylosed incisors related to age and growth in children and adolescents.

Abstract: In growing individuals, infraposition of a reimplanted, ankylosed tooth may disrupt normal alveolar development and compromise prosthetic treatment. The aims of this study were to analyze the rate of infraposition of ankylosed incisors in growing subjects and to provide guidelines for the timing of extraction. The subjects comprised 30 boys and 12 girls, selected consecutively from patients on annual post-trauma follow-up, and observed for periods ranging from 1 to 10 years. Only patients with one replanted ankylosed maxillary central incisor were included, the homologous teeth with healthy periodontal ligaments serving as controls. Growth intensity was evaluated from analyses of annual body height measurements. The following four periods were established: before the growth spurt, from initial to maximal growth spurt, from maximal growth spurt to the end and after the growth spurt. In 11 patients, cephalograms were taken at diagnosis and at extraction. Progression of infraposition varied individually. Diagnosis before the age of 10 or before the growth spurt was associated with very high risk of severe infraposition. In these cases the ankylosed tooth should be removed within 2-3 years. If ankylosis develops during the growth spurt, the tooth should be monitored regularly, but no intervention is indicated provided the adjacent teeth do not tilt and infraposition is minor or stable. Annual body height measurements, indicating the intensity of skeletal growth, are an aid to assessment. Cephalometric radiographs are important for evaluating the direction of growth of the jaws since there is a difference between horizontal and vertical growers.

The prevalence of traumatic injuries treated in the pedodontic clinic of Ankara University, Turkey, during 18 months.

Abstract: – The purpose of this study was to evaluate the type and prevalence of dental injuries referred to Ankara University, School of Dentistry, Department of Pedodontics, Turkey. One hundred and forty-seven patients with 234 traumatized teeth presented during 18-month interval. Of the 147 patients, 85 were boys and 62 were girls. The most frequent trauma occurred in the age of 11 years. The maxillary central incisors were found to be the most affected tooth in both primary and permanent dentition injuries. The maxillary arch is involved in a higher percentage of trauma cases (95.72%). The most common cause of injuries are falls (67.34%). In the primary dentition, the most common type of injury is extrusive luxation (38.23%) and in the permanent dentition, it is fracture of enamel–dentin without pulpal involvement (50.5%). From 147 patients, only 82 presented to our clinic within 1 h and 10 days after the injury time. It reveals that there is a need to inform the public of what they should do in cases of dental trauma, and how important it is to contact a dentist immediately.

Effect of immediate intracanal placement of Ledermix Paste® on healing of replanted dog teeth after extended dry times

Abstract: Ledermix Paste is a paste containing triamcinolone and demeclocycline with demonstrated anti-inflammatory activity that may slow down resorptive processes after severe traumatic injuries to the dentition. A total of 29 premolar roots of six mongrel dogs were extracted and instrumented with rotary nickel titanium files. Fifteen of these roots were then filled with a calcium hydroxide (Ca(OH)2) slurry and 14 roots were filled with Ledermix Paste paste. All accesses were sealed with glass ionomer and the roots replanted after an extraoral dry time of 60 min. After 4 months, the dogs were killed and the roots prepared for histological evaluation. Five-micrometer thick cross-sections of the root and surrounding tissue taken every 90 micro m were evaluated for healing. In addition, residual root mass was also measured to determine the extent of root structure loss for each treatment method. The Ledermix Paste-treated roots had statistically significantly more healing and less resorption than the roots treated with Ca(OH)2. Root filling with Ledermix Paste also resulted in significantly less loss in root mass due to resorption compared to those roots filled with Ca(OH)2. Immediate intracanal placement of Ledermix Paste at the emergency visit after an avulsion injury appears to decrease resorption and increase favorable healing.

The esthetic outcome of autotransplanted premolars replacing maxillary incisors

Abstract: Autotransplantation of developing premolars to replace maxillaryincisors has been documented to provide physiologically sound results, but comprehensive studies of the esthetic outcome have not been made previously. In order to assess the applicability of this approach and to identifyfactors important for planning of treatment, 22 autotransplanted premolars reshaped to incisor morphologywere compared to their natural, contralateral maxillaryincisors byscoring of features considered important for esthetics (color, soft tissue appearance, tooth morphology, and position). The sum of scores for each feature was used to place the reshaped transplant in one of three categories ^ Match, Deviate, Mismatch. The 22 patients were asked to ¢ll in a questionnaire which addressed the same features that were examined professionally, and the responses were categorized as either Satis¢ed, Acceptable, or Dissatis¢ed. Eleven of the 22 patients had received orthodontic treatment with ¢xed appliances following the transplantation. Most of the transplanted premolars matched the contralateral incisor, and the majorityof patients were satis¢ed with the appearance of the transplant. Fourteen percent of the transplants were categorized as Mismatch and 18% of patients reported dissatisfaction. The distribution in categories assessed professionallyand bythe patients was not signi¢cantlydiierent. The color and gingival width of the transplanted tooth were scored as diierent from the natural incisor in about half of the bilateral comparisons. For those teeth categorized professionallyas Mismatch and bypatients as Dissatis¢ed, a potential for esthetic improvement could be identi¢ed, as allocation to these categories was primarilydue to suboptimal positioning and restorative build- up of the transplant. Inter-disciplinaryplanning is important for successful esthetic results.

Sports dentistry and dental traumatology

Abstract: Sports dentistry had its origins in the 1980s. More recently, the Academy for Sports Dentistry joined forces with the International Association of Dental Traumatology in cosponsoring the World Congress on Sports Dentistry and Dental Traumatology. It is the intent of the present paper to introduce readers to the arena of sports dentistry, suggest future areas for collaborative research, and stimulate authors to submit high quality, scientifically based manuscripts on sports dentistry to Dental Traumatology.

Dental emergencies presenting to a dental teaching hospital due to complications from traumatic dental injuries

Abstract: In Jordan, only two surveys of dental trauma have been carried out. The aim of this study was to determine the incidence and pattern of dental emergencies resulting from traumatic injuries, as well as treatment provided to children presenting with these dental emergencies. Over a 1-year period, 620 children presented to our pediatric dental clinics with dental emergencies; 195 (31%) of these emergencies were a consequence of dental trauma to 287 teeth and were included in the study. The average time between the trauma and the dental emergency was 5 months. Pain or sensitivity was the most frequent presenting symptom (31.3%) followed by swelling or sinus tract (17.4%). The age of these patients ranged from 15 months to 14 years, with an average age of 9.3 years. Males accounted for 75.4% of the children in the samples, whereas females accounted for only 24.6%. The main cause of dental trauma was falling during play (58.5%); the least common cause was motor vehicle accidents, accounting for only 1.5% of all injuries. Most of the dental injuries occurred at home (41.5%), around noon time. The most commonly involved teeth were permanent maxillary central incisors accounting for 79.5% of all teeth involved by dental trauma. The most frequently encountered type of trauma in this sample was crown fracture seen in 76.6% of the teeth. Soft tissue injuries were estimated to occur in 16.9% of the children. The treatment received by the children in the sample ranged from no active treatment (6.2%) to elaborate dental procedures such as pulp therapy (41.3%) and prosthetic replacement of missing teeth (5.1%).

Factors affecting resorption in traumatically intruded permanent incisors in children

Abstract: There is a lack of consensus concerning the management of intruded permanent teeth. The objectives of the present study were to determine the prevalence of resorption for intruded permanent teeth and to establish the effect of factors on the timing, prevalence and rate of resorption and to examine the relationship between the timing of onset and the subsequent rate of resorption. Sixty-one intruded permanent incisors treated at the Paediatric Dentistry units in Belfast and Newcastle upon Tyne, during the period 1990-99 with a minimum follow-up period of 1.5 years, were studied. The timing and presence of resorption and its rate of occurrence over time were set as the principal outcomes. There was a significantly earlier onset and higher prevalence of resorption in more severely intruded teeth (P< 0.05). There was also a significant relationship between the degree of apical development and resorption with an increased prevalence in the more fully developed roots (P< 0.001). Resorption was detected significantly earlier in teeth with higher rates of resorption (P< 0.05). However, the treatment method did not significantly affect the prevalence or rate of resorption. In conclusion, the occurrence of root resorption after intrusive trauma appears to be related to the severity of the original injury and the stage of root development rather than the repositioning procedure.

Autotransplantation of immature third molars: influence of different splinting methods and fixation periods.

Abstract: – Different data were published documenting the influence of fixation methods and periods on the outcome of autotransplantations of teeth. Besides studies reporting increased ankylosis and disturbances of pulpal revascularization following rigid or extended fixation, there are studies revealing no connection in this matter. The clinical and radiological results of 76 transplanted germs of third molars were to be assessed after a rigid fixation for 4 weeks or after a suture splinting for 7 days and compared with each other. The choice of fixation method depended on the initial stability of the transplant. After a mean observation period of 3.4 years (range 1.0–6.1 years), 92.9% of the teeth stabilized with a suture, but only 73.5% fixed with an acid-etch composite and wire splint could be classified as successful (P = 0.029). The significant increases in ankylosis (P = 0.036) and pulp necrosis (P = 0.041) were the factors for the less favorable results of the rigidly fixed teeth. Our data support the results of other experimental and clinical studies with regard to the negative influences of an extended and rigid fixation on the success of tooth transplantation. However, apart from a correlation with the method and period of fixation, we also suspect the influence of an incongruity between the transplant and recipient site.

Healing and prognosis of teeth with intra‐alveolar fractures involving the cervical part of the root

Abstract: Healing and long-term prognosis of 94 cervical root fractures were evaluated. The teeth were divided into two groups according to type of fracture: transverse fractures limited to the cervical third of the root (51 incisors) and oblique fractures involving both the cervical and middle parts of the root (43 incisors). Neither the frequency nor the type of fracture healing differed significantly between the two groups. In the material as a whole, healing of the fracture with hard tissue formation was observed in 17 teeth (18%), and healing with interposition of periodontal ligament (PDL) and, in some cases, hard tissue between the fragments in 62 teeth (66%). Fifteen teeth (16%) showed no healing and a radiolucency adjacent to the fracture. Statistical analyses revealed that incomplete root formation and a positive sensibility test at the time of injury were significantly related to both healing and hard tissue repair. The same applied to concussion or subluxation compared with dislocation of coronal fragment, as well as optimal compared with suboptimal reposition of displaced coronal fragments. The type and duration of splinting (or no splinting) appeared to be of no significance for frequency or type of healing of cervical root fractures. During the observation time (mean = 75 months), 19 (44%) of the teeth with transverse fractures and 3 (8%) of those with oblique fractures were lost after healing. In conclusion, fractures in the cervical part of the root had a healing potential and the predictive parameters identified for fractures in other parts of the root seemed to be valid for the healing of cervical root fractures. Transverse fractures appeared to have a significantly poorer long-term prognosis compared to oblique fractures, apparently due to a marked post-treatment mobility, which often led to new luxation caused by even minor impacts.

Knowledge and prevention of dental trauma in team handball in Switzerland and Germany.

Abstract: The aim of this work was to conduct a comparative study between Switzerland and Germany about the frequency of dental injuries in handball, athletes' habits of wearing mouthguard, as well as the general level of information about first emergency measures after a dental trauma and the resulting consequences for athletes and their coaches alike. For this, using interviews, seven handball teams each in two countries (Switzerland/Germany) belonging to the amateur and semiprofessional leagues were surveyed. A total of 112 individuals, 28 females and 84 males, were interviewed. Thirty-two of the 112 interviewees have once observed a dental injury; 12 have experienced a dental injury themselves. Only 10 individuals wore a mouthguard. The results show that the area of handball still requires more information and education.

Clinical and epidemiological study of traumatic root fractures

Abstract: The aim of this work was to study the prevalence and clinical presentation of root fractures in a series of patients with dental trauma. Treatment strategies were classified and outcomes after a 6-month period presented. The study population comprised 76 patients (between the ages of 2 and 55 years) with 93 root fractures in their teeth (18 primary, 75 permanent). Data were collected following the taking of a detailed clinical history, objective clinical examination and photographic and radiological investigation. Since most of the primary teeth were extracted, only cases with root fracture of permanent teeth were followed-up: in all, 24 patients with 31 teeth with root fractures. The prevalence of root fractures in permanent teeth was 7.7% of all injuries, while in primary teeth it was 3.8%. The most frequently involved teeth were the maxillary incisors with a percentage of 75% in permanent teeth. Moreover, 40% of root fractures in permanent teeth were associated with fracture of the alveolar bone and of the soft tissues and in 45% of cases, the adjacent teeth were also injured. The results of this study reaffirm the necessity for scrupulous diagnosis of teeth after a traumatic injury. Adjacent teeth and those in the opposing arch should not be ignored. Treatment is multidisciplinary, requiring surgical, orthodontic, operative and prosthetic compliance. Periodic check-up is essential.

PCNA-expression of cementoblasts and fibroblasts on the root surface after extraoral rinsing for decontamination.

Abstract: – Periodontal cells capable of proliferation were studied immunohistochemically on extracted human teeth after 2-min irrigation with saline or ozonized water and marking of Proliferating Cell Nuclear Antigen (PCNA). All specimens expressed PCNA. The labelling index (LI), i.e. the number of positive cells compared to the total number of cells, was 6.6% after irrigation with saline and 7.8% after irrigation with ozone. There was no difference in number and distribution of PCNA-positive cells from the coronal to the apical thirds of the roots. Irrigation with ozonized water showed higher labelling indices in comparison with saline, but this could not be statistically substantiated (P = 0.24). Ozonized water, not being isotonic, had no negative effect on periodontal cells remaining on the tooth surface after irrigation for 2 min.

Clinical procedures for the immediate reattachment of a tooth fragment.

Abstract: Uncomplicated crown fractures are frequent dental injuries, especially in young patients. It is beneficial to quickly restore the function and the aesthetics of the traumatized tooth. The immediate fragment reattachment is a therapeutic choice for uncomplicated anterior crown fractures, when the tooth is not luxated and the fragment is correctly stored. The aim of this article is to present the clinical procedures for the immediate fragment reattachment by accurate bonding procedures. The immediate fragment reattachment is a very conservative treatment: it allows the restoration of the original dental anatomy, thus rehabilitating function and aesthetics in a short time, by preserving dental tissues.

Reinforcing effect of a resin glass ionomer in the restoration of immature roots in vitro

Abstract: – Fifty-six extracted maxillary central incisors were used for this study. The crown of each tooth was removed in order to obtain a standard length of 13 mm. Root canals were enlarged to simulate immature teeth after apexification. The apical 2 mm of the root canal was obturated with gutta-percha and AH26 sealer. The specimens were divided into two groups. Group A was unrestored and served as positive control. In group B, the canal walls were reinforced with a resin modified glass ionomer using a translucent curing post. All teeth were subjected to compressive force using an Instron testing machine until fracture occurred. Group B showed an increased resistance to fracture (456.02 ± 172.47 N) compared with group A (263.46 ± 98.00 N). The difference between groups was statistically significant (P < 0.005).

Vertical root fracture treated by bonding fragments and rotational replantation.

Abstract: These case reports describe a new treatment method for complete vertical root fractures. This method is composed of two steps. First, the fractured tooth is intentionally extracted atraumatically, and then the separated fragments are bonded with an adhesive resin cement. The restored tooth is replanted by rotating approximately 180 degrees into the original socket and fixing with an orthodontic wire. For both cases reported here, bone regeneration was observed at the 3-year follow-up. Since this modality adopts the respective advantages of both intentional replantation and adhesive treatment, it might be the treatment of choice in cases of vertical root fracture.

Effects of temperature, storage time and media on periodontal and pulpal healing after replantation of incisors in monkeys.

Abstract: The effect of temperature of various storage media and at varying storage periods upon periodontal ligament (PDL) and pulpal healing after tooth replantation was examined in green vervet monkeys (Cercopithecus aethiops). Mandibular lateral incisors with mature root formation were extracted and kept in dry storage at 22, 4 and -18 degrees C; in saline at 37, 22, 4 and -18 degrees C; or in saliva (i.e. in the buccal vestibule) at 37 degrees C for either 60 or 120 min prior to replantation. The animals were sacrificed 8 weeks after replantation and the replanted teeth examined histometrically. The following histological parameters were registered for each tooth: normal PDL, surface resorption, inflammatory resorption, replacement resorption (ankylosis), downgrowth of pocket epithelium, periapical inflammatory changes, and the extent of vital pulp. A total of 125 replanted teeth were examined. Storage in saliva at 37 degrees C showed a similar amount of normal PDL compared to saline storage for both 60 and 120 min. Saline storage for 60 or 120 min showed no difference in the extent of normal PDL when storage was compared at 37, 22 and 4 degrees C. However, storage at -18 degrees C resulted in significantly less normal PDL than storage at other temperatures. Dry storage for 60 min showed significantly less root resorption at 4 degrees C compared to 22 degrees C. Furthermore, dry storage at -18 degrees C showed significantly less normal PDL than storage at 4 degrees C. When the dry storage period was extended to 120 min, no difference was found between 22, 4 and -18 degrees C. It is concluded that the temperature (above 0 degrees C) of the storage medium is of importance only for dry storage and in such a situation only for shorter extra-alveolar periods, i.e. for 60-min storage and not for 120 min, where extensive destruction of the PDL always takes place. It is suggested that the temperature effect of 4 degrees C could be related to less evaporation from the PDL and thereby less damage to the PDL cells or a strict temperature effect upon cell metabolism. Pulp healing in all the cases was limited to the entrance of the pulp canal, and no significant pattern was found between storage media, time and temperature.

Assessment of post-traumatic PDL cells viability by a novel collagenase assay

Abstract: Both length of extra-alveolar time and type of storage media are significant factors that can affect the long-term prognosis for replanted teeth. Numerous studies have examined various media in an attempt to determine the ideal material for storage of the avulsed tooth. The purpose of this study was to compare the number of viable periodontium ligament (PDL) cells in different storage media using a collagenase assay. Thirty-three freshly extracted human teeth were divided into four experimental and two control groups. The positive and negative controls corresponded to 0 min and an 8-h dry time, respectively. The experimental teeth were stored dry for 30 min and then immersed in one of four media (Hank's balanced salt solution (HBSS), milk, saline, water) for 45 min. The teeth were then treated with dispase grade II and collagenase for 30 min. The number of viable and nonviable PDL cells was counted with a hemocytometer and analyzed. An ANOVA demonstrated no statistically significant differences in the viability of PDL cells among saline, HBSS and milk. Within the parameters of this study, it appears that milk or saline is an equally viable alternative to HBSS for storage of avulsed teeth.

Effects and distribution of the enamel matrix derivative Emdogain® in the periodontal tissues of rat molars transplanted to the abdominal wall

Abstract: – The enamel matrix derivative Emdogain® (EMD) has been found to promote regeneration of lost periodontal tissues We have studied the effects and distribution of EMD in the periodontal tissues of maxillary rat molars transplanted to a subcutaneous position in the abdominal wall The molars were transplanted with or without EMD either immediately after extraction or after drying for 30 min After 2 days, 1, 2 or 4 weeks the rats were killed and the teeth were examined by means of light microscopy and immunohistochemistry with anti-amelogenin antibodies Teeth transplanted immediately after extraction showed formation of alveolar bone separated from the dental roots by a periodontal space, regardless of the use of EMD Among the teeth that were transplanted with EMD after drying for 30 min, new alveolar bone was formed in five out of eight teeth after 2 and 4 weeks None of the teeth that were dried for 30 min and transplanted without EMD showed alveolar bone formation Only one tooth transplanted with EMD showed root resorption after drying, while resorption was noted in all teeth transplanted without EMD All teeth that were transplanted with EMD and none of the teeth that were transplanted without EMD showed an immunohistochemical reaction for amelogenin After 2 days, amelogenin was precipitated on all surfaces exposed at the transplantation procedure Later, the immunoreactive material was redistributed to cells at the root surface, where it was still demonstrable after 4 weeks In conclusion, EMD is accumulated in cells at the root surface and promotes regeneration of the periodontal tissues of the transplanted teeth It also seems to promote healing of root resorption

Treatment of replacement resorption with Emdogain® − a prospective clinical study

Abstract: The present clinical study investigated the outcome of intentional replantation using Emdogain for periodontal healing following trauma-related ankylosis. Sixteen ankylosed teeth aiected by replacement resorption were treated as follows: After tooth extraction, the root canal was obturated with a retrograde titanium post. Emdogain was applied to the root surface and into the extraction socket with subsequent replantation of the tooth. Evaluation parameters included horizontal and vertical Periotest scores, percussion sound and periapical radiographs. All ¢ndings were compared to those of the adjacent teeth. The mean follow-up period was 15 months (range 4^24 months). Eleven teeth showed no signs of recurrence of ankylosis: they were in full function and exhibited no pathological clinical ¢ndings. Four severely traumatized teeth demonstrated a recurrence of ankylosis after a mean period of 6 months, one tooth was lost in a second accident after 7 months. The estimated probability of 1year without recurrence of ankylosis was P ¼ 0.66 (95% con¢dence interval (0.40; 0.94)). The mean survival time was 10.2 months (SD 1.1). The results indicate that treatment of replacement resorption following light to moderate trauma with replantation and Emdogain appears to prevent or delay recurrence of ankylosis in many cases.

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

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