Background: Lennox-Gastaut syndrome (LGS) is a severe form of childhood epilepsy that is defined ... more Background: Lennox-Gastaut syndrome (LGS) is a severe form of childhood epilepsy that is defined by generalized multiple type seizures, slowness of intellectual growth, and a specific EEG disturbance. Children affected might previously have infantile spasms or underlying brain disorder but etiology can be idiopathic. In South Africa, the incidence of secondary epilepsy is higher than what is found in developed countries resulting in higher incidence of the disease. LGS seizures are often treatment resistant and the long term prognosis is poor.
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2002
This report describes 3 cases of ciliated epithelium-lined radicular cysts among 256 apical perio... more This report describes 3 cases of ciliated epithelium-lined radicular cysts among 256 apical periodontitis lesions and also illustrates the occurrence of an Actinomyces-infected periapical cyst. Serial and step serial sections of 256 plastic-embedded root apices with attached apical periodontitis lesions that were prepared for a previous investigation were reviewed for the presence of ciliated epithelium-lined radicular cysts. The lesions that were found to have such epithelial lining were examined in a transmission electron microscope to elaborate the fine structure of the ciliated cells. A total of 3 ciliated columnar epithelium-lined cysts was found among the 256 apical periodontitis lesions examined. Two of the lesions also contained stratified squamous epithelium. All 3 lesions affected maxillary premolars. One of the lesions was a true cyst, and the other 2 were periapical pocket cysts. The lumen of 1 of the latter revealed the presence of typical "ray-fungus" actinomycotic colonies. Although the stratified squamous component of the epithelia that lined the radicular cysts reported here may be derived from the cell rests of Malassez, the ciliated epithelial cells may be of sinus origin. Microbial agents from diseased root canals can advance into radicular cysts, particularly in pocket cysts, with the possible threat of such infection in upper posterior teeth spreading into the maxillary sinus.
Trials aiming at isolating cultures and subcultures of cells from the periodontal ligament to unc... more Trials aiming at isolating cultures and subcultures of cells from the periodontal ligament to uncover special features of such tissue-residing population are related to the past decade [1]. Moreover, the idea of cell-delivery systems, and especially with stem cells, to initiate periodontal regeneration is not new. However, describing suitable animal models for such new techniques is less documented in the literature and sometimes underestimated. The wide range of animal species allows appropriate selection of bio-models for different investigations. Each species has unique similarities and dissimilarities to humans. While many studies could ensure the initiation of periodontal regeneration using stem cells extracted from the periodontium, seeding of human periodontium-derived stem cells (pdSCs) on collagen carriers could induce major features of periodontal regeneration when implanted in experimental periodontal defects in the athymic immunodeficient rat as could be shown in our studies. However, remarkable notifications regarding the results obtained in our studies were the induction of malignant tumors (squamous cell carcinoma) in the majority of investigated animals. Considering the data presented in the literature, our studies seems to be the first that demonstrates the initiation of malignant tumors when using human pdSCs. The patients from whom the pdSCs had been extracted, the animal model used and a possible oncogenic alteration of the pdSCs themselves might all be factors behind the tumors’ initiation. In our present studies, the animal model used and the related experimental periodontal defect, as a heterologous model, could successfully present two important biological features after implantation of pdSCs; namely periodontal repair and tumorigenicity. Although not fully histo-morphometrically assessed in our studies, these features are very important for further investigations and for future more-controlled studies. However, further studies using advanced histological, immunological and genetic techniques are required to assure different supposals presented in the current studies regarding stem cell-based periodontal regeneration and stem cell-tumorigenesis.
This immunohistochemical study describes changes in the histology and in the distribution of the ... more This immunohistochemical study describes changes in the histology and in the distribution of the basement membrane components laminin and collagen IV as well as of the cytokeratins (CK)1/2/10/11, CK5/6, CK13, CK14, CK17, CK19 during the take of free split mucosa (epithelial and connective tissue) transplants in humans up to 36 months post-operative. Histology showed a flattening of the epithelial layer within the first 2 weeks after grafting, followed initially by an increase (25-30 layers, week 6) and later on by a decrease of cell layers in the epithelium (15-20 layers, week 20). From that time onwards, clear stratification and reteridges as signs of differentiation were present. Up to day 14 of graft take, the linear staining patterns for laminin and collagen IV were interrupted, which was not observed at any later stage. During this early interval CK5/6, CK1/2/10/11, CK14 and CK17 were expressed in all epithelial layers. The reactions for CK5/6 and CK1/2/10/11 were less intensive. At 6 weeks, CK1/2/10/11 stained the intermediate and superficial layers, being consistent with findings after longer graft take. CK5/6 reacted in the basal and intermediate cell layers, and CK13, CK14 and CK17 reacted in all layers. In the following period up to week 20, CK5/6 were found in the parabasal cells of the intermediate cell layers and the basal cells. CK14 staining was confined to these cell layers too, but also showed some reaction in the superficial layers. CK13 and CK17 were still bound to all layers. At 7 months post-operative, CK5/6 and CK14 were seen in their typical localisation in the basal cell layer and the parabasal cells of the intermediate layers, CK17 was seen mainly in the intermediate layer and CK13 was seen in focal areas of all layers. Anti-CK19 reacted only with single basal and parabasal cells up to week 20. These results suggest that during healing of mucosal autografts there is a sequence of changes in the expression of cell biological differentiation markers that may involve an epithelio-connective tissue interaction before the typical patterns for the donor side were observed again on the gingiva or mucosa of the hard palate.
In maxillofacial surgery, intrasulcular incisions are often used. This prospective case series wa... more In maxillofacial surgery, intrasulcular incisions are often used. This prospective case series was established to evaluate the detrimental effects of intrasulcular incisions on periodontal structures. In 35 patients, measurements of probing depth and crown length before and 10 months postoperatively were performed to calculate changes of attachment level and gingival recession. In a subgroup, surgically treated sites were compared with untreated control sites. A nonparametric test was applied for longitudinal and split-mouth comparisons. Overall, intrasulcular incisions did not induce significant attachment loss. The frequency of sites losing ≥2 mm of attachment was 5.0%, 2.6%, and 4.7% at mesial, buccal, and distal sites, respectively. Intrasulcular incisions caused only a slight increase in gingival recession by 0.4 ± 0.5, 0.2 ± 0.3, and 0.3 ± 0.4 mm at mesial, buccal, and distal sites, respectively. Within the limitations of the study design, it can be concluded that intrasulcular incisions without additional vertical incisions do not impose a serious risk for attachment loss and/or gingival recession.
Tissue engineering technologies combine the biological properties of living cells and physicochem... more Tissue engineering technologies combine the biological properties of living cells and physicochemical properties of individually designed materials in order to enable the creation of artificial tissues like cartilage, bone, mucosa, periodontium, etc. for potential use in oral and maxillofacial surgery. Living cells, three-dimensional cell housing scaffolds, and bioactive factors are used to produce an implantable tissue forming device for regenerative and functional repair. The aim of the discipline, oral and maxillofacial surgery is to develop reconstructive and regenerative tissue engineering technologies. This goal can be reached by surgically oriented research including: cell sources, growth and differentiation, bioreactors, experimental and clinical applications like cartilage, bone, and periodontal tissue engineering. The understanding of fundamental biology associated with tissue regeneration will be essential for the development of approaches to enhance cell function, angiogenesis, and cell differentiation in the future.
Stem cell therapy is a promising area in regenerative medicine. Periodontal granulation tissues a... more Stem cell therapy is a promising area in regenerative medicine. Periodontal granulation tissues are often discarded during conventional surgery. If stromal stem cells can be isolated from these tissues, they can be used for subsequent surgery on the same patient. Fifteen human periodontal granulation tissue samples were obtained from intrabony defects during surgery. Immunohistochemistry (IHC) was carried out on five of the samples to identify STRO-1, a marker of mesenchymal stem cells. Five samples underwent flow cytometry analysis for the same marker. The remaining five samples were characterized by “colony formation unit-fibroblast” (CFU-f) assay and selected for proliferation assay, flow cytometry of stem cell markers, immunocytochemistry (ICC), multipotent differentiation assays, and repairing critical-size defects in mice. The ratio of STRO-1+ cells detected by IHC was 5.91 ± 1.50%. The analysis of flow cytometry for STRO-1 was 6.70 ± 0.81%. Approximately two thirds of the CFU-f colonies had a strong reaction to STRO-1 in ICC staining. The cells were multipotent both in vitro and in vivo. Mice given bone grafts and stem cells showed significantly better bone healing than those without stem cells. Multipotent stromal stem cells can be isolated from human periodontal granulation tissues. These cells improve new bone formation when transplanted in mouse calvarial defects. Isolating stem cells from relatively accessible sites without extra procedures is clinically advantageous. This study demonstrated that human periodontal granulation tissues contain isolatable multipotent stem cells. The cells may be a good source for autotransplantation in subsequent treatment.
The plastic periodontal surgery includes not only the stop of the progression of gingival recessi... more The plastic periodontal surgery includes not only the stop of the progression of gingival recession, but also, if possible, the complete coverage of exposed root surfaces and the improvement of the functional and aesthetic mucogingival conditions. Repair or regeneration of lost structures up to a certain extent is possible with the currently known evidence-based and minimal invasive methods of plastic periodontal surgery. Die plastische Parodontalchirurgie beinhaltet nicht nur einen Stopp der Progression der gingivalen Rezession, sondern auch, wenn möglich, die vollständige Deckung der exponierten Wurzeloberfläche und die Verbesserung der funktionellen und ästhetischen mucogingivalen Verhältnisse. Mit den heute bekannten minimalinvasiven und Evidenz basierenden Methoden der plastischen Parodontalchirurgie ist die Regeneration beziehungsweise Reparation der verloren gegangenen Strukturen bis zu einem bestimmten Ausmaß möglich.
A rare case of well-differentiated squamous-cell carcinoma arising in the epithelial lining of a ... more A rare case of well-differentiated squamous-cell carcinoma arising in the epithelial lining of a lateral periodontal cyst is reported. Submission of surgically removed tissues for histopathologic evaluation is emphasized. The surgical site has been reconstructed and functions well. Because of early diagnosis and treatment, the patient has no evidence of clinical disease 2% years postoperatively.
La recherche de protocoles favorisant l’hémostase et la cicatrisation est un problème récurrent d... more La recherche de protocoles favorisant l’hémostase et la cicatrisation est un problème récurrent dans toutes les disciplines chirurgicales. Les concentrés plaquettaires, en tant que colles biologiques enrichies en cytokines, ont été utilisés dans une multitude de situations cliniques afin d’évaluer leurs effets présumés. En ophtalmologie, ils furent ajoutés au traitement chirurgical des déchirures de la macula. En chirurgie plastique, ils servent de colles de fibrine afin de prévenir la formation de cicatrices chéloïdes, au rendu esthétique et aux qualités mécaniques très préjudiciables. En chirurgies parodontale, péri-implantaire et maxillofaciale, ils jouent le rôle de liant biologique entre les différents éléments d’une greffe osseuse ou gingivale et de gel de protection du site opératoire, au même titre que les colles de fibrine utilisées antérieurement. Cependant, les travaux publiés souffrent de nombreux biais et de l’absence de méthodologie réellement scientifique pour en évaluer la portée. Et ces lacunes analytiques renforcent les doutes quant à l’identité biologique de ces préparations : gel plaquettaire ou colle de fibrine ?The search for protocols supporting the haemostasis and the cicatrisation is a recurring problem in all the surgical disciplines. The platelet concentrates, as biological adhesives enriched in cytokines, were used in a multitude of clinical situations in order to evaluate their supposed effects. In ophthalmology, they were added to the surgical treatment of macular holes. In plastic surgery, they are used as fibrin adhesives in order to prevent the formation of keloid scars, which aesthetic and mechanical qualities are very prejudicial. In periodontal, peri-implant and maxillo-facial surgeries, they play the biological role of link between various elements during bone grafts or gingival surgeries and the role of protective seal in the operational site, as well as the fibrin adhesives used before. However, published works suffer from many skews and the really scientific absence of methodology to evaluate the range of it. And these analytical gaps reinforce the doubts as for the biological identity of these preparations: platelet gel or fibrin adhesive?
Various periodontal plastic surgical techniques are employed in obtaining root coverage. Recently... more Various periodontal plastic surgical techniques are employed in obtaining root coverage. Recently, the use of an enamel matrix derivative (EMD) has been reported in such treatment. We report 2 cases of root coverage surgery with a coronally positioned flap in combination with EMD (CPFםEMD) and connective tissue graft in combination with EMD (CTGםEMD). Case 1: The patient was a 25-year-old woman referred to Suidobashi Hospital, Tokyo Dental College for root coverage surgery on the lower right first premolar. Gingival recession was classified as Miller Class II, as no alveolar bone loss or loss of attachment was observed in the interdental area, although recession had progressed to the mucogingival junction. The patient was diagnosed with local gingival recession caused by excessive tooth brushing. Primary conservative treatment failed to reduce the gingival recession. Subsequently, root coverage surgery with CPFםEMD was carried out. As observation at the 1-year follow-up revealed complete root coverage and no recurrence of root exposure or subjective symptoms, the postoperative course was considered to be favorable. Case 2: The patient was a 39-year-old woman referred to Suidobashi Hospital, Tokyo Dental College for root coverage surgery on the lower left canine. Gingival recession was classified as Miller Class II. Root coverage surgery with CTGםEMD was carried out. As observation at the 2-month follow-up revealed complete root coverage and no recurrence of root exposure, the postoperative course was considered to be favorable. These 2 cases indicate the effectiveness of root coverage surgery with CPFםEMD and CTGםEMD.
A reliable, soft tissue allograft, AlloDerm ® is reported in this preliminary study. Processed fr... more A reliable, soft tissue allograft, AlloDerm ® is reported in this preliminary study. Processed from allograft skin obtained from tissue banks, it is an acellular dermal graft whose native framework is maintained. This dermal graft has been used in conjunction with ultrathin autografts to ...
Today an increasing number of patients seek aesthetic improvement through minimally invasive proc... more Today an increasing number of patients seek aesthetic improvement through minimally invasive procedures, and interest in soft tissue augmentation and filling agents is rising steadily. However, a thorough understanding of these substances, their indications and contraindications, as well as a profound knowledge of different implantation techniques is essential to provide an aesthetically pleasing result for the patient. This presentation gives an overview of the current injectable biomaterials, their major indications, advantages and disadvantages, with focus on collagen, hyaluronic acid, poly-l-lactide, and autologous fat grafting.
We present the case of Kindler syndrome in a 17-year-old man. After excision, histomorphological ... more We present the case of Kindler syndrome in a 17-year-old man. After excision, histomorphological analysis, and wound closure of a chronic unstable scar in the right popliteal region, a basal cell carcinoma was diagnosed accidentally. A malignancy was not suspected, although the patient already had biopsies, multiple trials of debridement, and skin grafting earlier elsewhere. While an initial attempt to close the defect with a microsurgical flap was abandoned, due to microvascular irregularities, a wound closure was achieved with a free skin graft. The postoperative histomorphologic analysis revealed the surprising diagnosis of a basal cell carcinoma, fortunately with free margins. At follow-up 1 year later, the grafted area was stable, and there was no recurrent disease. A preoperative histomorphologic analysis of the complete excised chronic wound, especially in known skin disorders—regardless of young age—is mandatory. Furthermore, the presented case showed that an abnormal deposition of collagen, and enhanced coprostasis with migration of granulocytes, destroys the normal consistency of small vessels and presents a limitation for microsurgical procedures in these patients.
Descending necrotizing soft tissue infections involving the neck and chest are a rare but hazardo... more Descending necrotizing soft tissue infections involving the neck and chest are a rare but hazardous sequela of periodontal infections. These infections are associated with significant mortality.The high mortality rates of this condition are attributed to significant delays in diagnosis and treatment of common periodontal infections that have progressed to severe disease without overt clinical signs or symptoms. As with all necrotizing soft tissue infections, making a timely diagnosis requires that the examining physician maintain a reasonable index of suspicion when the patient with an oropharyngeal infection is encountered. Coverage of the most common infecting organisms with appropriate antibiotics accompanies surgical therapy. Hyperbaric oxygen remains an adjunctive therapy of unproven efficacy. The cornerstone of therapy, however, is surgical with aggressive and complete debridement of all nonviable tissue without regard for the size or complexity of the resulting wound. In the case described below, this goal could not have been achieved without the immediate availability of reconstructive expertise to preserve vital structures in the neck and upper mediastinum.
Parodontale chirurgie is niet beperkt tot de chirurgische behandeling van het geïnfecteerde parod... more Parodontale chirurgie is niet beperkt tot de chirurgische behandeling van het geïnfecteerde parodontium. In 1993 introduceerde Miller de term periodontal plastic surgery, in het Nederlands‘parodontale plastische chirurgie’. Deze omvat alle chirurgische ingrepen die gericht zijn op het voorkomen en corrigeren van anatomische afwijkingen, ontwikkelingsstoornissen en traumatische of pathologische afwijkingen van de gingiva, de alveolaire mucosa en het alveolaire bot. In korte tijd is er grote belangstelling voor parodontale plastische chirurgie ontstaan. Vorig jaar, op het congres van de European Federation of Periodontology (EFP) in Stockholm, kreeg dit onderwerp heel veel aandacht. Voorbeelden van parodontale plastische chirurgie zijn: gingiva-augmentatie (zie ook TP nr. 3, 2010), recessiebedekking (TP nr. 12, 2009), behandeling van peri-implantaire zachte weefsels, kroonverlenging, frenulumextirpatie, socket preservation technique (TP nr. 5, 2010), papilla preservation technique, ridge augmentation technique en parodontale regeneratie met glazuurmatrix proteïnen (Emdogain). Alveolaire botchirurgie, zoals botaugmentatie, behoort tevens tot deze groep en wordt vooral uitgevoerd tijdens (pre-)implantologische behandelingen. In dit artikel wordt op enkele van deze technieken dieper ingegaan.
Background: Lennox-Gastaut syndrome (LGS) is a severe form of childhood epilepsy that is defined ... more Background: Lennox-Gastaut syndrome (LGS) is a severe form of childhood epilepsy that is defined by generalized multiple type seizures, slowness of intellectual growth, and a specific EEG disturbance. Children affected might previously have infantile spasms or underlying brain disorder but etiology can be idiopathic. In South Africa, the incidence of secondary epilepsy is higher than what is found in developed countries resulting in higher incidence of the disease. LGS seizures are often treatment resistant and the long term prognosis is poor.
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2002
This report describes 3 cases of ciliated epithelium-lined radicular cysts among 256 apical perio... more This report describes 3 cases of ciliated epithelium-lined radicular cysts among 256 apical periodontitis lesions and also illustrates the occurrence of an Actinomyces-infected periapical cyst. Serial and step serial sections of 256 plastic-embedded root apices with attached apical periodontitis lesions that were prepared for a previous investigation were reviewed for the presence of ciliated epithelium-lined radicular cysts. The lesions that were found to have such epithelial lining were examined in a transmission electron microscope to elaborate the fine structure of the ciliated cells. A total of 3 ciliated columnar epithelium-lined cysts was found among the 256 apical periodontitis lesions examined. Two of the lesions also contained stratified squamous epithelium. All 3 lesions affected maxillary premolars. One of the lesions was a true cyst, and the other 2 were periapical pocket cysts. The lumen of 1 of the latter revealed the presence of typical "ray-fungus" actinomycotic colonies. Although the stratified squamous component of the epithelia that lined the radicular cysts reported here may be derived from the cell rests of Malassez, the ciliated epithelial cells may be of sinus origin. Microbial agents from diseased root canals can advance into radicular cysts, particularly in pocket cysts, with the possible threat of such infection in upper posterior teeth spreading into the maxillary sinus.
Trials aiming at isolating cultures and subcultures of cells from the periodontal ligament to unc... more Trials aiming at isolating cultures and subcultures of cells from the periodontal ligament to uncover special features of such tissue-residing population are related to the past decade [1]. Moreover, the idea of cell-delivery systems, and especially with stem cells, to initiate periodontal regeneration is not new. However, describing suitable animal models for such new techniques is less documented in the literature and sometimes underestimated. The wide range of animal species allows appropriate selection of bio-models for different investigations. Each species has unique similarities and dissimilarities to humans. While many studies could ensure the initiation of periodontal regeneration using stem cells extracted from the periodontium, seeding of human periodontium-derived stem cells (pdSCs) on collagen carriers could induce major features of periodontal regeneration when implanted in experimental periodontal defects in the athymic immunodeficient rat as could be shown in our studies. However, remarkable notifications regarding the results obtained in our studies were the induction of malignant tumors (squamous cell carcinoma) in the majority of investigated animals. Considering the data presented in the literature, our studies seems to be the first that demonstrates the initiation of malignant tumors when using human pdSCs. The patients from whom the pdSCs had been extracted, the animal model used and a possible oncogenic alteration of the pdSCs themselves might all be factors behind the tumors’ initiation. In our present studies, the animal model used and the related experimental periodontal defect, as a heterologous model, could successfully present two important biological features after implantation of pdSCs; namely periodontal repair and tumorigenicity. Although not fully histo-morphometrically assessed in our studies, these features are very important for further investigations and for future more-controlled studies. However, further studies using advanced histological, immunological and genetic techniques are required to assure different supposals presented in the current studies regarding stem cell-based periodontal regeneration and stem cell-tumorigenesis.
This immunohistochemical study describes changes in the histology and in the distribution of the ... more This immunohistochemical study describes changes in the histology and in the distribution of the basement membrane components laminin and collagen IV as well as of the cytokeratins (CK)1/2/10/11, CK5/6, CK13, CK14, CK17, CK19 during the take of free split mucosa (epithelial and connective tissue) transplants in humans up to 36 months post-operative. Histology showed a flattening of the epithelial layer within the first 2 weeks after grafting, followed initially by an increase (25-30 layers, week 6) and later on by a decrease of cell layers in the epithelium (15-20 layers, week 20). From that time onwards, clear stratification and reteridges as signs of differentiation were present. Up to day 14 of graft take, the linear staining patterns for laminin and collagen IV were interrupted, which was not observed at any later stage. During this early interval CK5/6, CK1/2/10/11, CK14 and CK17 were expressed in all epithelial layers. The reactions for CK5/6 and CK1/2/10/11 were less intensive. At 6 weeks, CK1/2/10/11 stained the intermediate and superficial layers, being consistent with findings after longer graft take. CK5/6 reacted in the basal and intermediate cell layers, and CK13, CK14 and CK17 reacted in all layers. In the following period up to week 20, CK5/6 were found in the parabasal cells of the intermediate cell layers and the basal cells. CK14 staining was confined to these cell layers too, but also showed some reaction in the superficial layers. CK13 and CK17 were still bound to all layers. At 7 months post-operative, CK5/6 and CK14 were seen in their typical localisation in the basal cell layer and the parabasal cells of the intermediate layers, CK17 was seen mainly in the intermediate layer and CK13 was seen in focal areas of all layers. Anti-CK19 reacted only with single basal and parabasal cells up to week 20. These results suggest that during healing of mucosal autografts there is a sequence of changes in the expression of cell biological differentiation markers that may involve an epithelio-connective tissue interaction before the typical patterns for the donor side were observed again on the gingiva or mucosa of the hard palate.
In maxillofacial surgery, intrasulcular incisions are often used. This prospective case series wa... more In maxillofacial surgery, intrasulcular incisions are often used. This prospective case series was established to evaluate the detrimental effects of intrasulcular incisions on periodontal structures. In 35 patients, measurements of probing depth and crown length before and 10 months postoperatively were performed to calculate changes of attachment level and gingival recession. In a subgroup, surgically treated sites were compared with untreated control sites. A nonparametric test was applied for longitudinal and split-mouth comparisons. Overall, intrasulcular incisions did not induce significant attachment loss. The frequency of sites losing ≥2 mm of attachment was 5.0%, 2.6%, and 4.7% at mesial, buccal, and distal sites, respectively. Intrasulcular incisions caused only a slight increase in gingival recession by 0.4 ± 0.5, 0.2 ± 0.3, and 0.3 ± 0.4 mm at mesial, buccal, and distal sites, respectively. Within the limitations of the study design, it can be concluded that intrasulcular incisions without additional vertical incisions do not impose a serious risk for attachment loss and/or gingival recession.
Tissue engineering technologies combine the biological properties of living cells and physicochem... more Tissue engineering technologies combine the biological properties of living cells and physicochemical properties of individually designed materials in order to enable the creation of artificial tissues like cartilage, bone, mucosa, periodontium, etc. for potential use in oral and maxillofacial surgery. Living cells, three-dimensional cell housing scaffolds, and bioactive factors are used to produce an implantable tissue forming device for regenerative and functional repair. The aim of the discipline, oral and maxillofacial surgery is to develop reconstructive and regenerative tissue engineering technologies. This goal can be reached by surgically oriented research including: cell sources, growth and differentiation, bioreactors, experimental and clinical applications like cartilage, bone, and periodontal tissue engineering. The understanding of fundamental biology associated with tissue regeneration will be essential for the development of approaches to enhance cell function, angiogenesis, and cell differentiation in the future.
Stem cell therapy is a promising area in regenerative medicine. Periodontal granulation tissues a... more Stem cell therapy is a promising area in regenerative medicine. Periodontal granulation tissues are often discarded during conventional surgery. If stromal stem cells can be isolated from these tissues, they can be used for subsequent surgery on the same patient. Fifteen human periodontal granulation tissue samples were obtained from intrabony defects during surgery. Immunohistochemistry (IHC) was carried out on five of the samples to identify STRO-1, a marker of mesenchymal stem cells. Five samples underwent flow cytometry analysis for the same marker. The remaining five samples were characterized by “colony formation unit-fibroblast” (CFU-f) assay and selected for proliferation assay, flow cytometry of stem cell markers, immunocytochemistry (ICC), multipotent differentiation assays, and repairing critical-size defects in mice. The ratio of STRO-1+ cells detected by IHC was 5.91 ± 1.50%. The analysis of flow cytometry for STRO-1 was 6.70 ± 0.81%. Approximately two thirds of the CFU-f colonies had a strong reaction to STRO-1 in ICC staining. The cells were multipotent both in vitro and in vivo. Mice given bone grafts and stem cells showed significantly better bone healing than those without stem cells. Multipotent stromal stem cells can be isolated from human periodontal granulation tissues. These cells improve new bone formation when transplanted in mouse calvarial defects. Isolating stem cells from relatively accessible sites without extra procedures is clinically advantageous. This study demonstrated that human periodontal granulation tissues contain isolatable multipotent stem cells. The cells may be a good source for autotransplantation in subsequent treatment.
The plastic periodontal surgery includes not only the stop of the progression of gingival recessi... more The plastic periodontal surgery includes not only the stop of the progression of gingival recession, but also, if possible, the complete coverage of exposed root surfaces and the improvement of the functional and aesthetic mucogingival conditions. Repair or regeneration of lost structures up to a certain extent is possible with the currently known evidence-based and minimal invasive methods of plastic periodontal surgery. Die plastische Parodontalchirurgie beinhaltet nicht nur einen Stopp der Progression der gingivalen Rezession, sondern auch, wenn möglich, die vollständige Deckung der exponierten Wurzeloberfläche und die Verbesserung der funktionellen und ästhetischen mucogingivalen Verhältnisse. Mit den heute bekannten minimalinvasiven und Evidenz basierenden Methoden der plastischen Parodontalchirurgie ist die Regeneration beziehungsweise Reparation der verloren gegangenen Strukturen bis zu einem bestimmten Ausmaß möglich.
A rare case of well-differentiated squamous-cell carcinoma arising in the epithelial lining of a ... more A rare case of well-differentiated squamous-cell carcinoma arising in the epithelial lining of a lateral periodontal cyst is reported. Submission of surgically removed tissues for histopathologic evaluation is emphasized. The surgical site has been reconstructed and functions well. Because of early diagnosis and treatment, the patient has no evidence of clinical disease 2% years postoperatively.
La recherche de protocoles favorisant l’hémostase et la cicatrisation est un problème récurrent d... more La recherche de protocoles favorisant l’hémostase et la cicatrisation est un problème récurrent dans toutes les disciplines chirurgicales. Les concentrés plaquettaires, en tant que colles biologiques enrichies en cytokines, ont été utilisés dans une multitude de situations cliniques afin d’évaluer leurs effets présumés. En ophtalmologie, ils furent ajoutés au traitement chirurgical des déchirures de la macula. En chirurgie plastique, ils servent de colles de fibrine afin de prévenir la formation de cicatrices chéloïdes, au rendu esthétique et aux qualités mécaniques très préjudiciables. En chirurgies parodontale, péri-implantaire et maxillofaciale, ils jouent le rôle de liant biologique entre les différents éléments d’une greffe osseuse ou gingivale et de gel de protection du site opératoire, au même titre que les colles de fibrine utilisées antérieurement. Cependant, les travaux publiés souffrent de nombreux biais et de l’absence de méthodologie réellement scientifique pour en évaluer la portée. Et ces lacunes analytiques renforcent les doutes quant à l’identité biologique de ces préparations : gel plaquettaire ou colle de fibrine ?The search for protocols supporting the haemostasis and the cicatrisation is a recurring problem in all the surgical disciplines. The platelet concentrates, as biological adhesives enriched in cytokines, were used in a multitude of clinical situations in order to evaluate their supposed effects. In ophthalmology, they were added to the surgical treatment of macular holes. In plastic surgery, they are used as fibrin adhesives in order to prevent the formation of keloid scars, which aesthetic and mechanical qualities are very prejudicial. In periodontal, peri-implant and maxillo-facial surgeries, they play the biological role of link between various elements during bone grafts or gingival surgeries and the role of protective seal in the operational site, as well as the fibrin adhesives used before. However, published works suffer from many skews and the really scientific absence of methodology to evaluate the range of it. And these analytical gaps reinforce the doubts as for the biological identity of these preparations: platelet gel or fibrin adhesive?
Various periodontal plastic surgical techniques are employed in obtaining root coverage. Recently... more Various periodontal plastic surgical techniques are employed in obtaining root coverage. Recently, the use of an enamel matrix derivative (EMD) has been reported in such treatment. We report 2 cases of root coverage surgery with a coronally positioned flap in combination with EMD (CPFםEMD) and connective tissue graft in combination with EMD (CTGםEMD). Case 1: The patient was a 25-year-old woman referred to Suidobashi Hospital, Tokyo Dental College for root coverage surgery on the lower right first premolar. Gingival recession was classified as Miller Class II, as no alveolar bone loss or loss of attachment was observed in the interdental area, although recession had progressed to the mucogingival junction. The patient was diagnosed with local gingival recession caused by excessive tooth brushing. Primary conservative treatment failed to reduce the gingival recession. Subsequently, root coverage surgery with CPFםEMD was carried out. As observation at the 1-year follow-up revealed complete root coverage and no recurrence of root exposure or subjective symptoms, the postoperative course was considered to be favorable. Case 2: The patient was a 39-year-old woman referred to Suidobashi Hospital, Tokyo Dental College for root coverage surgery on the lower left canine. Gingival recession was classified as Miller Class II. Root coverage surgery with CTGםEMD was carried out. As observation at the 2-month follow-up revealed complete root coverage and no recurrence of root exposure, the postoperative course was considered to be favorable. These 2 cases indicate the effectiveness of root coverage surgery with CPFםEMD and CTGםEMD.
A reliable, soft tissue allograft, AlloDerm ® is reported in this preliminary study. Processed fr... more A reliable, soft tissue allograft, AlloDerm ® is reported in this preliminary study. Processed from allograft skin obtained from tissue banks, it is an acellular dermal graft whose native framework is maintained. This dermal graft has been used in conjunction with ultrathin autografts to ...
Today an increasing number of patients seek aesthetic improvement through minimally invasive proc... more Today an increasing number of patients seek aesthetic improvement through minimally invasive procedures, and interest in soft tissue augmentation and filling agents is rising steadily. However, a thorough understanding of these substances, their indications and contraindications, as well as a profound knowledge of different implantation techniques is essential to provide an aesthetically pleasing result for the patient. This presentation gives an overview of the current injectable biomaterials, their major indications, advantages and disadvantages, with focus on collagen, hyaluronic acid, poly-l-lactide, and autologous fat grafting.
We present the case of Kindler syndrome in a 17-year-old man. After excision, histomorphological ... more We present the case of Kindler syndrome in a 17-year-old man. After excision, histomorphological analysis, and wound closure of a chronic unstable scar in the right popliteal region, a basal cell carcinoma was diagnosed accidentally. A malignancy was not suspected, although the patient already had biopsies, multiple trials of debridement, and skin grafting earlier elsewhere. While an initial attempt to close the defect with a microsurgical flap was abandoned, due to microvascular irregularities, a wound closure was achieved with a free skin graft. The postoperative histomorphologic analysis revealed the surprising diagnosis of a basal cell carcinoma, fortunately with free margins. At follow-up 1 year later, the grafted area was stable, and there was no recurrent disease. A preoperative histomorphologic analysis of the complete excised chronic wound, especially in known skin disorders—regardless of young age—is mandatory. Furthermore, the presented case showed that an abnormal deposition of collagen, and enhanced coprostasis with migration of granulocytes, destroys the normal consistency of small vessels and presents a limitation for microsurgical procedures in these patients.
Descending necrotizing soft tissue infections involving the neck and chest are a rare but hazardo... more Descending necrotizing soft tissue infections involving the neck and chest are a rare but hazardous sequela of periodontal infections. These infections are associated with significant mortality.The high mortality rates of this condition are attributed to significant delays in diagnosis and treatment of common periodontal infections that have progressed to severe disease without overt clinical signs or symptoms. As with all necrotizing soft tissue infections, making a timely diagnosis requires that the examining physician maintain a reasonable index of suspicion when the patient with an oropharyngeal infection is encountered. Coverage of the most common infecting organisms with appropriate antibiotics accompanies surgical therapy. Hyperbaric oxygen remains an adjunctive therapy of unproven efficacy. The cornerstone of therapy, however, is surgical with aggressive and complete debridement of all nonviable tissue without regard for the size or complexity of the resulting wound. In the case described below, this goal could not have been achieved without the immediate availability of reconstructive expertise to preserve vital structures in the neck and upper mediastinum.
Parodontale chirurgie is niet beperkt tot de chirurgische behandeling van het geïnfecteerde parod... more Parodontale chirurgie is niet beperkt tot de chirurgische behandeling van het geïnfecteerde parodontium. In 1993 introduceerde Miller de term periodontal plastic surgery, in het Nederlands‘parodontale plastische chirurgie’. Deze omvat alle chirurgische ingrepen die gericht zijn op het voorkomen en corrigeren van anatomische afwijkingen, ontwikkelingsstoornissen en traumatische of pathologische afwijkingen van de gingiva, de alveolaire mucosa en het alveolaire bot. In korte tijd is er grote belangstelling voor parodontale plastische chirurgie ontstaan. Vorig jaar, op het congres van de European Federation of Periodontology (EFP) in Stockholm, kreeg dit onderwerp heel veel aandacht. Voorbeelden van parodontale plastische chirurgie zijn: gingiva-augmentatie (zie ook TP nr. 3, 2010), recessiebedekking (TP nr. 12, 2009), behandeling van peri-implantaire zachte weefsels, kroonverlenging, frenulumextirpatie, socket preservation technique (TP nr. 5, 2010), papilla preservation technique, ridge augmentation technique en parodontale regeneratie met glazuurmatrix proteïnen (Emdogain). Alveolaire botchirurgie, zoals botaugmentatie, behoort tevens tot deze groep en wordt vooral uitgevoerd tijdens (pre-)implantologische behandelingen. In dit artikel wordt op enkele van deze technieken dieper ingegaan.
Uploads
Papers by harem jaafar