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Background/aim: Delayed (dry storage > 60 minutes) replantation results in ankylosis and replacement resorption. It has been suggested to remove the non-viable periodontal ligament before replantation to possibly reduce the rate of replacement resorption. However there has been no study on the rate of replacement resorption after such measures. The aim of this study was to investigate if there was any difference in the rate of replacement resorption by either removing the periodontal ligament (PDL) with gauze or not removing PDL in teeth subjected to delayed replantation followed by healing for 2 or 6 weeks.Materials and Methods: Maxillary central incisors were extracted in 8 rabbits. In the right central incisors, the necrotic PDL was removed by dry gauze over the root surface. In the left eight extracted teeth PDL was left on the root surface. All extracted teeth were left to dry for 60 minutes. Extra-oral root canal treatment was performed before replantation. The rabbits were sacrificed after 2 weeks and 6 weeks respectively. Histologic processing and evaluation was done.Results: In the 2 weeks group, all teeth showed ankylosis. The cementum was intact, and fusion of the bone and root was generally seen without resorption of the root, whereas in the 6 weeks group regardless of whether PDL had been kept or not, ankylosis and osseous replacement of the dentin was seen. There was no evidence of inflammatory infiltrate in the sections examined.Conclusion: Removal of PDL prior to delayed replantation may result in some initial protection of the cementum during the first few weeks. However, over longer times there seems to be neither protection of the dentin from ankylosis and osseous replacement, nor any influence on the rate of replacement resorption. [ABSTRACT FROM AUTHOR]

Background/aim: Prevalence and incidence of diabetes are increasing and many dental trauma patients today have diabetes. The implications of delayed wound healing, associated with diabetes mellitus, on oral mucosal wound healing have not been investigated extensively. The aim of this study was to investigate the implications of diabetes mellitus on the cellular, vascular, and fibroblastic changes induced by laceration on the oral mucosa of Wistar rats.Materials and Methods: Sixteen female Wistar rats were randomly assigned into two groups: 1. Experimental Streptozotocin-induced diabetic group (8 rats). 2. Control group (8 rats). A standardized laceration injury was induced from the corner of the mouth to the mid-check penetrating through dermal and oral mucosal contaminated by saliva. Samples were taken from the rats after sacrificing them on days 1,3,7, and 10. Inflammation was evaluated both qualitatively and quantitatively. Two investigators evaluated samples in a blinded manner.Results: Histology reports indicated delayed wound healing patterns in diabetic rats through days 1, 3, 7, and 10 when compared to controls. Inflammation was also noted to be consistently present more often in diabetic rats. Furthermore, polymorphonuclear cell count was consistently higher in diabetic rats.Conclusion: The results suggest that oral mucosa wound healing is delayed in diabetic Wistar rats compared to non-diabetic rats in terms of wound closure, angiogenesis, and polymorphonuclear cells number. Furthermore, it is also suggested that wound healing is impaired both in the early and late stages of soft tissue wound healing. [ABSTRACT FROM AUTHOR]

Aim: To develop an experimental in vivo model to study dentoalveolar ankylosis and osseous replacement resorption after delayed replantation.Materials and Methods: The maxillary right incisors of eight rabbits were extracted and replanted, while the maxillary left incisors served as controls. A special technique for extraction was used, luxating the incisor laterally prior to extraction. Extra-oral root canal treatment was performed. In four of the eight replanted teeth, periodontal ligament was removed using gauze. All teeth were replanted after one-hour dry storage. A horizontal line was drilled on the labial enamel surface of the incisors to enable registration of possible subsequent infraposition. The rabbits were sacrificed after 1 week or 4 weeks, respectively. Percussion test of the teeth was carried out and infraposition was registered. Histological processing and evaluation were performed.Results: Percussion sound was normal after 1 week and high in the 4 week group; infraposition was noted in all replanted teeth in the 4-week group. Fusion between the bone and dentin was seen in some areas on the root already after 1 week, but there was little or no osseous replacement. Larger areas of ankylosis were seen in the 4-week group although not significant, but deeper progressive osseous replacement was noted in this group. There was no significant difference in ankylosis with regard to periodontal ligament removal or not. Pulp and periodontal tissues were normal in all control teeth.Conclusion: The rabbit tooth model may be useful for experimental in-vivo studies on delayed replantation, subsequent ankylosis, osseous replacement and infraposition. [ABSTRACT FROM AUTHOR]

Aim Candida adherence is implicated in the pathogenesis of oral candidosis. Adhesion to buccal epithelial cells ( BEC), germ tube ( GT) formation, and relative cell surface hydrophobicity ( CSH) are colonization attributes of candidal pathogenicity. Candida dubliniensis ( C. dubliniensis) is allied with recurrent oral candidosis, which can be treated with nystatin, amphotericin B, ketoconazole, and fluconazole. Due to the diluent effect of saliva and the cleansing effect of the oral musculature in the oral cavity C. dubliniensis isolates undergo brief and sequential exposure to antifungal agents during therapy. Thus, in the present study, we evaluated the adhesion to BEC, GT formation, and the CSH of oral isolates of C. dubliniensis following brief and sequential exposure to nystatin, amphotericin B, ketoconazole, and fluconazole. Methods After determining the minimum inhibitory concentration ( MIC) of the aforementioned drugs, 20 oral isolates of C. dubliniensis were briefly (1 h), and sequentially (10 days) exposed to subcidal concentrations of these drugs. Following drug removal, adhesion to BEC, GT formation, and CSH of these isolates were determined. Results The percentage reduction of adhesion to BEC, GT formation, and CSH of the isolates following exposure to antifungal agents were as follows: nystatin: 53.55%, 33.98%, and 29.83% ( P < 0.001); amphotericin B: 53.84%, 36.23%, and 28.97% ( P < 0.001); ketoconazole: 37.43%, 20.51%, and 16.49% ( P < 0.001); and fluconazole: 8.93% ( P < 0.001), 1.6%, and 0.63% ( P > 0.05). Conclusions Brief and sequential exposure of C. dubliniensis to antifungal agents would continue to wield an antifungal effect by altering its adhesion attributes, and elucidate possible pharmacodynamics by which antifungal agents might operate in modulating candidal adherence. [ABSTRACT FROM AUTHOR]

Candida albicans is the major aetiological agent of oral candidosis and one of its important virulent factors is the production of extracellular phospholipases, which can be modulated by subtherapeutic concentrations of antifungal agents thus decreasing their pathogenicity. Hence, considering that chlorhexidine gluconate ( CG) is a common antimicrobial mouthwash used in dentistry and that its concentration in the mouth reaches subtherapeutic levels during dosage intervals due to the diluent effect of saliva and cleansing effect of the oral musculature, the postantifungal effect ( PAFE) and the phospholipase production of oral C. albicans following brief exposure to subtherapeutic concentrations of CG was studied. Fifty C. albicans planktonic oral isolates obtained from smokers, diabetics, asthmatics using steroid inhalers, partial denture wearers and healthy individuals were exposed to three subtherapeutic concentrations of CG (0.005%, 0.0025% and 0.00125%) for 1 h. Isolates unexposed to CG was the control group. Thereafter the antiseptic was removed and the PAFE and phospholipase production was determined by a turbidometric method and a plate assay using an egg yolk agar medium respectively. Mean PAFE (hours) of 50 oral isolates of C. albicans following 1-h exposure to 0.005%, 0.0025% and 0.00125% CG was 6.97, 1.85 and 0.62 respectively. The phospholipase production of these isolates was significantly suppressed with a percentage reduction of 21.68, 18.20 and 14.04% following exposure to 0.005%, 0.0025% and 0.00125% CG respectively. Brief exposure of C. albicans isolates to subtherapeutic concentrations of CG would wield an antifungal effect by suppressing growth and phospholipase production, thereby quelling its pathogenicity. [ABSTRACT FROM AUTHOR]

Dentoalveolar ankylosis with osseous replacement is often seen after replantation of avulsed teeth, and this process may be used for preservation of alveolar crests after trauma. Its exact mechanisms with regard to osteoinductive properties are not yet fully understood and need to be systematically investigated. Dentin can possibly act as a slow-releasing carrier of bone morphogenic proteins ( BMP), and this property of dentin has been proposed to be used as an alternative or supplement to bone grafting in the maxillofacial region. We aimed to initially asses host tissue reactions to dentin by implanting dentin blocks of autogenic and xenogenic human origin in rabbit connective tissue of the abdominal wall and femoral muscle. Animals were sacrificed after a period of 3 months, and histological processing, sectioning and examinations were carried out. Bone formation, cell counts and thickness of capsule surrounding the grafts were evaluated. Only minor signs of heterotopic bone formation were seen. There were no significant differences between autografts and xenografts or grafts implanted in connective tissue or muscle with regards to tissue reactions except for a significant difference ( P = 0.018) in findings of more local inflammatory cells in relation to grafts placed in connective tissue in the autograft group. We conclude that during the time frame of this study, non-demineralized dentin, whether autogenous or xenogenic did not have the potential to induce bone formation when implanted in non-osteogenic areas such as the abdominal wall and abdominal muscle of rabbits. [ABSTRACT FROM AUTHOR]

The postantifungal effect ( PAFE) has an impact on candidal pathogenicity. However, there is no information on either the PAFE or its impact on adhesion traits of oral Candida dubliniensis isolates. Oral candidosis can be treated topically with nystatin. Adhesion to buccal epithelial cells ( BEC), germ tube ( GT) formation and relative cell surface hydrophobicity ( CSH) are all colonisation attributes of candidal pathogenicity. Hence, the main objective of this study was to investigate the in vitro PAFE on 20 C. dubliniensis isolates following exposure to nystatin. In addition, the impact of nystatin-induced PAFE on adhesion to BEC, GT formation and relative CSH of C. dubliniensis isolates were also evaluated. After determining the minimum inhibitory concentration ( MIC) of nystatin, C. dubliniensis isolates were exposed to sublethal concentrations of nystatin for 1 h. Following this exposure, the drug was removed and PAFE, adhesion to BEC, GT formation and relative CSH were determined by a previously described turbidometric method, adhesion assay, germ tube induction assay and biphasic aqueous-hydrocarbon assay respectively. MIC (μg/ml) of C. dubliniensis isolates to nystatin ranged from 0.09 to 0.78. The nystatin-induced mean PAFE (hours) on C. dubliniensis isolates was 2.17. Compared with the controls, exposure to nystatin suppressed the ability of C. dubliniensis isolates to adhere BEC, GT formation and relative CSH by a mean percentage reduction of 74.45% ( P < 0.0001), 95.92% ( P < 0.0001) and 34.81 ( P < 0.05) respectively. Hence, brief exposure of C. dubliniensis isolates to nystatin would continue to wield an antifungal effect by suppressing growth as well as its adhesion attributes. [ABSTRACT FROM AUTHOR]

Purpose From traumatology, it is well known that dentoalveolar ankylosis results in osseous replacement and formation of new bone. This principle is used after decoronation for preservation of the height and width of the alveolar bone crest after trauma. Dentin possesses bone-forming properties and may possibly also be used as a bone augmentation material prior to implant placement. The aim of this study was to investigate whether xenogenic dentin particles inserted into the marrow space of rabbit tibia, a space where there is no solid bone tissue initially, would contribute to new bone formation. Materials and Methods Dentin chips from human teeth were inserted into tibias of ten New Zealand rabbits. The tibial bones were processed for histology after 6 months, and new bone formation was quantified. Results Bone formation was ranging from 0 to 86% on the dentin fragments, and there was minor inflammation. Bone formation was seen to a larger extent on dentin grafts located close to the native tibial bone wall. There was a significant correlation ( r = −0.579, P < 0.001) between the amount of bone formation around the dentin graft and distance to the tibial cortical wall. Conclusion Dentin promotes new bone formation when located close to native cortical bone and may have a potential as a bone augmentation material. [ABSTRACT FROM AUTHOR]

Adherence of Candida has been implicated as the initial process in the pathogenesis of oral candidosis. Candidal germ tubes and its relative cell-surface hydrophobicity ( CSH) are contributory attributes. Candida dubliniensis is currently documented as an opportunistic pathogen allied with recurrent oral candidosis. Oral candidosis can be treated with polyene and azole antifungals such as amphotericin B, ketoconazole and fluconazole. However, the intraoral concentration of these drugs fluctuates and becomes sub-therapeutic because of the diluent effect of saliva and cleansing effect of the oral musculature. Hence, intraorally, the pathogenic yeast may undergo a brief exposure to antifungal drugs. The objective of this study was to investigate the effect of brief exposure to sub-lethal concentrations of these antifungals on the germ tube formation and CSH of C. dubliniensis. After determining the minimum inhibitory concentration of the drugs, 20 oral isolates of C. dubliniensis were exposed to sub-lethal concentrations of these antifungals for 1 h. Following this brief exposure, the drugs were removed, and following subsequent incubation in a germ tube inducing medium and exposure to bi-phasic hydrocarbon assay, the germ tube formation and CSH of these isolates was quantified respectively. Compared with controls, exposure to amphotericin B almost completely suppressed the ability to form germ tubes with a mean percentage reduction of 95.91% ( P < 0.0001), whereas ketoconazole and fluconazole also significantly inhibited germ tube formation but to a lesser degree with a mean percentage reduction of 18.73% and 12.01% respectively ( P < 0.05). Compared with controls, exposure to amphotericin B and ketoconazole elicited a significant suppression on CSH with a mean percentage reduction of 33.09% and 21.42%, respectively ( P < 0.001), whereas exposure to fluconazole did not elicit a significant suppression on CSH (9.21%; P > 0.05). In clinical terms it appears that, even a short exposure to sub-lethal concentrations of these drugs, a situation all too familiar in the oral environment, would continue to exert an antifungal effect by suppressing the pathogenic potency of C. dubliniensis. [ABSTRACT FROM AUTHOR]

Candidal adhesion has been implicated as the initial step in the pathogenesis of oral candidiasis and cell surface hydrophobicity (CSH) has been implicated in adhesion to mucosal surfaces. Candida dubliniensis is an opportunistic pathogen associated with recurrent oral candidiasis. Chlorhexidine gluconate is by far the commonest antiseptic mouth wash prescribed in dentistry. At dosage intervals the intraoral concentration of this antiseptic fluctuates considerably and reaches sub-therapeutic levels due to the dynamics of the oral cavity. Hence, the organisms undergo only a limited exposure to the antiseptic during treatment. The impact of this antiseptic following such exposure on CSH of C. dubliniensis isolates has not been investigated. Hence, the main objective of this study was to investigate the effect of brief exposure to sub-therapeutic concentrations of chlorhexidine gluconate on the CSH of C. dubliniensis isolates. Twelve oral isolates of C. dubliniensis were briefly exposed to three sub-therapeutic concentrations of 0.005%, 0.0025% and 0.00125% chlorhexidine gluconate for 30 min. Following subsequent removal of the drug, the CSH of the isolates was determined by a biphasic aqueous-hydrocarbon assay. Compared with the controls, exposure to 0.005% and 0.0025% chlorhexidine gluconate suppressed the relative CSH of the total sample tested by 44.49% ( P < 0.001) and 21.82% ( P < 0.018), respectively, with all isolates being significantly affected. Although exposure to 0.00125% of chlorhexidine gluconate did not elicit a significant suppression on the total sample tested (7.01%; P > 0.05), four isolates of the group were significantly affected. These findings imply that exposure to sub-therapeutic concentrations of chlorhexidine gluconate may suppress CSH of C. dublinienis isolates, thereby reducing its pathogenicity and highlights further the pharmacodynamics of chlorhexidine gluconate. [ABSTRACT FROM AUTHOR]

Several studies regarding knowledge and attitudes of dental students towards H IV/AIDS have been reported from various countries. However, to the best of our knowledge, an international comparison between countries with diverse cultural and educational backgrounds has not been reported in the literature. The aim of this study was to compare the knowledge and attitudes towards HIV/AIDS of dental students of Kuwait University (KU), Kuwait and the University of Peradeniya (UP), Sri Lanka, the only dental schools in the respective countries. A cross-sectional survey was conducted among a total of 258 dental students, representing the clinical years of both universities, using a similar structured questionnaire with sixty questions to examine their knowledge of various aspects of HI V/AIDS and thirteen questions to examine their attitudes towards the disease. The mean knowledge and attitude scores were calculated and compared between students from the two universities using t-test with SPSS 17.0. A total of 215 questionnaires were completed and returned, giving a total response rate of 83.3 percent. The KL students were significantly more knowledgeable (p=0.018) regarding HIV/AIDS than the UP students. However, the UP students demonstrated a more highly significant positive attitude (p<0.001) towards the disease than those in KU. This information might help to define strategies to improve the quality of education in these countries. [ABSTRACT FROM AUTHOR]

Traumatic granuloma is an uncommon condition considered to be a benign, reactive lesion that usually affects the tongue. The exact pathogenesis implicated in the development of this lesion is not clear. However, trauma has been found to be a contributing factor in a majority of the cases. Clinically, it often presents as an ulceration or an indurated submucosal mass. Microscopically, it is characterized by a diffuse polymorphic cell infiltrate composed predominantly of eosinophils extending deep into the submucosa causing degeneration of the underlying muscle. Recognition of the lesion is important because it often mimics oral squamous cell carcinoma. But traumatic granuloma is self-limiting and tends to resolve spontaneously. This paper describes a case of traumatic granuloma on the dorsal surface of tongue in a 62-year-old woman. The clinical aspects, pathogenesis and histopathology of this uncommon lesion are discussed with an emphasis on its benign, self-limiting nature. [ABSTRACT FROM AUTHOR]

Background and Aim: Dentin contains bone morphogenic protein which is important in bone induction and dentin can act as a slow releasing carrier. This property may possibly be used as an alternative or supplement to bone grafting to defective areas after trauma prior to treatment with osseointegrated implants. Hence, the objective of this study was to investigate if dentin can be used as a graft in bone defects in an experimental rabbit model. Materials and Methods: Eight New Zealand White Rabbits were used to prepare bone cavities either in the angle of the mandible or tibia. Six of the eight tibial and six of the eight mandibular bone defects were filled with dentin blocks from human premolars which were extracted for orthodontic treatment. Two mandibular and two tibial bone cavities were used as controls and all the rabbits were sacrificed after 3 months. Radiographic and histological examinations were performed. Results: There was a difference in healing pattern between the mandibular and tibial defects. In the mandible, the dentin blocks were resorbed to a larger extent and more often surrounded by fibrous tissue, probably due to the fact that the dentin blocks were mobile because of the thin mandibles and muscular activity in that area. Only some dentin blocks were ankylosed with the mandibular bone. In the tibia however, all dentin blocks were fused to bone over a large area. Osseous replacement resorption was seen. In control cavities, bone formation was seen but was never complete. No signs of inflammatory changes were seen in any fused grafts. Conclusions: Dentin grafts have a potential to be incorporated in bone without inflammation and can be used as bone inducer and later replaced by bone. Thus, rabbit tibia served as a better model for further studies of this phenomenon when compared to the mandible. [ABSTRACT FROM AUTHOR]

Topical anesthetics based on a combination of 2.5% lidocaine and 2.5% prilocaine are efficient in eliminating pain from needle stick when placed on skin and oral mucosa. This suggests their application in soft tissue lacerations before suturing to enable pain-free exploration and suturing of traumatic lacerations without prior injection needle stick. The aim of the present study was to study the healing of experimental oral lacerations after topical anesthetic substances were placed in the lacerations. Thirty-six standardized incisions were made bilaterally in the lower and the upper labial mucosa of nine white New Zealand rabbits. All wounds were intentionally contaminated with saliva to simulate laceration wounds in trauma situation. EMLA cream and Oraqix thermosetting gel were applied into 30 lacerations and six lacerations were left untreated as control. In some lacerations the topical anesthetic agent was left in the wound, while in others they were rinsed off by saline before suturing the laceration wound. The rabbits were then killed after 3 days, 2 weeks and 4 weeks of healing and the lips were processed for histological evaluation. Similar normal histological healing patterns were seen in wounds in which EMLA and Oraqix were applied compared with control lacerations at all stages of healing. No adverse tissue or foreign body reactions were seen in any of the lacerations. We conclude that EMLA and Oraqix can be used in oral mucosal lacerations prior to suturing without the risk of adverse tissue reaction. [ABSTRACT FROM AUTHOR]

Salako N, Joseph B, Ritwik P, Salonen J, John P, Junaid TA. Comparison of bioactive glass, mineral trioxide aggregate, ferric sulfate and formocresol as pulpotomy agents in rat molar. Dent Traumatol 2003; 19: 314–320. © Blackwell Munksgaard, 2003. Bioactive glass (BAG) is often used as a filler material for repair of dental bone defects. Although there is evidence of osteogenic potential of this material, it is not clear yet whether the material exhibits potential for dentinogenesis. Hence, the aim of the present study was to evaluate BAG as a pulpotomy agent and to compare it with three commercially available pulpotomy agents such as formocresol (FC), ferric sulfate (FS), and mineral trioxide aggregate (MTA). Pulpotomies were performed in 80 maxillary first molars of Sprague Dawley rats, and pulp stumps were covered with BAG, FC, FS, and MTA. Histologic analysis was performed at 2 weeks and then at 4 weeks after treatment. Experimental samples were compared with contra-lateral normal maxillary first molars. At 2 weeks, BAG showed inflammatory changes in the pulp. After 4 weeks, some samples showed normal pulp histology, with evidence of vasodilation. At 2 weeks, MTA samples showed some acute inflammatory cells around the material with evidence of macrophages in the radicular pulp. Dentine bridge formation with normal pulp histology was a consistent finding at 2 and 4 weeks with MTA. Ferric sulfate showed moderate inflammation of pulp with widespread necrosis in coronal pulp at 2 and 4 weeks. Formocresol showed zones of atrophy, inflammation, and fibrosis. Fibrosis was more extensive at 4 weeks with evidence of calcification in certain samples. Among the materials tested, MTA performed ideally as a pulpotomy agent causing dentine bridge formation while simultaneously maintaining normal pulpal histology. It appeared that BAG induced an inflammatory response at 2 weeks with resolution of inflammation at 4 weeks. [ABSTRACT FROM AUTHOR]

Aims: The aim of the present study was to determine the range, frequency, prevalence, and distribution of oral lesions submitted for histopathological diagnosis at the oral pathology laboratory at Kuwait University. Methods: A retrospective analysis was conducted of all cases submitted to the oral pathology laboratory over an 18‐year period. Age, sex, histopathological diagnosis, and location of the lesions were recorded. Lesions were classified into 10 diagnostic categories. Results: Of the 697 biopsies examined, the average age of the patients ranged from 1 to 93 years with a mean age of 37.83 ± 16.62 (mean ± SD). The most common diagnostic category was mucosal pathologies (N = 205, 29.4%), followed by odontogenic cysts (N = 158, 22.7%) and reactive lesions (N = 97, 13.9%). The three most common histopathological diagnoses were hyperkeratosis (N = 70), dentigerous cyst (N = 48), and mucocele (N = 44). Twenty‐five malignant neoplasms were diagnosed, the majority of them in males. A significant association was observed between age and the group of lesions of the oral cavity (P ≤ 0.001). Conclusions: The present study provides the first set of data from Kuwait that covers a wide range of oral lesions. Mucosal pathologies were the most frequently diagnosed lesions and the majority of diagnoses were benign. [ABSTRACT FROM AUTHOR]