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Notes: Abstract  – Root resorption is known to be the most relevant complication determining the long-term prognosis of allotransplanted teeth, and it is initiated during the first few postoperative months. The aim of the present study was to quantitatively assess the dynamics of the periodontal ligament (PDL) and pulpal healing reactions during the first 8 weeks after allotransplantation of mature teeth. The material comprised 112 maxillary central and mandibular lateral incisors of 28 mature green Vervet monkeys, immunogenetically untested, and only matched according to the size of the grafts. Donors and recipients exchanged simultaneously both maxillary incisors and one mandibular incisor, whereas the contralateral mandibular incisors were autotransplanted as controls. At random, every second maxillary allograft was endodontically treated preoperatively. Histoquantitative analysis of the PDL and pulpal healing reactions was carried out after 1, 2, 4 and 8 weeks on serial cross-sections of the grafts in 6, 6, 6 and 8 monkeys, respectively. Necrosis zones in the PDL were prominent in both auto- and allografts after 1 week. Inflammation in the PDL dominated healing in all types of grafts 1 week after transplantation, whereas it subsided significantly after 2 weeks in autografts compared to allografts (P = 0.005). Inflammatory resorption (IR) became prominent after 4 weeks in autografts and this remained stationary. In contrast, IR initiated significantly earlier in allografts compared to autografts after 2 weeks (P = 0.007), and this type of resorption was further increasing in allografts after 4 and 8 weeks. Endodontic treatment, however, reduced IR nearly totally in the allografts with time. Replacement resorption (RR) was nearly absent in autografts. In contrast, allografts showed increasing appearance of RR with time, initiating at 4 weeks. By removing IR from the allografts by endodontic treatment, RR was unmasked significantly at 4 weeks (P = 0.02) and dominated most of the periodontal ligament (70%) after 8 weeks (P = 0.0004). Within the 8 postoperative weeks autografts showed healing with increasing amount of normal PDL reaching significantly higher levels compared to allografts already after 2 weeks (P = 0.02), with increasing differences thereafter. In most allografts, the normal PDL occupied less than 10% of the entire root surface and was located in the supra-alveolar cervical region. Downgrowth of periodontal pocket epithelium was absent or found very infrequently in all groups irrespective of type, time and treatment.In conclusion, the healing of allo- and autotransplanted mature teeth differed significantly on several aspects during the first 8 postoperative weeks. The recorded differences included a higher amount of inflammation in the PDL of allografts after 2 weeks, inflammatory resorption from the second week, and replacement resorption dominating in the eighth week, indicated that an immunologic stimulus for root resorption existed in the allogenic PDL apart from the pulp. Furthermore, specific healing reactions was found in the cervical region with almost identical gingival healing in auto- and allografts.

Notes: 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.

Notes: Abstract— The aim of the present study was to describe the frequency of dental injuries over a 10-year period, where a mouthguard was used in approximately 10% of intubation cases or endoscopying. The types of injury are presented and the use of different types of mouthguard is discussed. Among 120 086 procedures involving anaesthesia carried out in thc period 1983–1992 at Bispebjerg Hospital, Copenhagen, 75 cases of dental trauma occurred. The incidence of dental traumatic injuries was 0.06′%. Although eight patients had used mouthguards they were registered with traumatic injuries to the teeth in connection with general anaesthesia. Of the patients, 58% were women and 42% men, with a mean age of 61 years. Seventy-eight percent of the injuries were located in the maxilla and 91% of these involved the ineisor area of the maxilla. Forty-one percent were classified as lateral luxations or mobile teeth, 47% were classified as fractured teeth, 10% tooth avulsions and the remaining 2% were classified as concussions. Because of the low frequency of traumatic dental injuries in connection with general anaesthesia and the non-significant effect of the use of mouthguards, routine use of mouthguards is not recommended. Only when a patient is to have an endoscopy done under general anaesthesia, and the surgeon or anaesthesiologist foresees problems (restricted mouth opening, extensive fixed prosthetics, extensive loss of marginal bone) is use of an individually made mouthguard indicated.

Notes: Using histochemical and immunohistochemical methods, we examined specimens of Candidal leukoplakia from the oral mucosa of 5 smokers to determine the morphological relationships between Candida and Langerhans cells (LC) in tissue sections. LC were fairly evenly distributed in control sections, but had a patchy distribution in lesions. Fewer LC were found in lesions than in control tissue, but the difference was not statistically significant. Candidal antigens were not detected on LC by the methods used, but we found ATPase-positive LC among, or at least near, intraepithelial candidal hyphae. However, sections double-reacted with anti-Candida and T6 antibodies to label candidal antigens and LC. respectively, showed a clear zone of epithelium between the T6-positivc LC and the candidal hyphae. The difference in distribution of ATPase-positive and T6-positive LC may indicate locations of 2 subtypes of LC, or a change in T6 antigen expression by the LC closest to the candidal hyphae.

Notes: 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 °C; in saline at 37, 22, 4 and −18 °C; or in saliva (i.e. in the buccal vestibule) at 37 °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 °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 °C. However, storage at −18 °C resulted in significantly less normal PDL than storage at other temperatures. Dry storage for 60 min showed significantly less root resorption at 4 °C compared to 22 °C. Furthermore, dry storage at −18 °C showed significantly less normal PDL than storage at 4 °C. When the dry storage period was extended to 120 min, no difference was found between 22, 4 and −18 °C. It is concluded that the temperature (above 0 °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 °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.