C. Sukotjo - Academia.edu (original) (raw)

Papers by C. Sukotjo

Journal of Dental Research, 2002

Tooth extraction is the most commonly prescribed ablation surgery in dentistry and results in the... more Tooth extraction is the most commonly prescribed ablation surgery in dentistry and results in the formation of edentulous mucosa. Although the edentulous mucosa serves as the critical interfacial tissue for removable and implant-assisted prostheses, the structure and physiology of this wound-induced tissue are largely uninvestigated. We addressed the hypothesis that tooth extraction activates the expression of a unique set of genes in healing edentulous mucosa. Using the Differential Display Polymerase Chain Reaction and 5′ Rapid Amplification of cDNA Ends protocols, we isolated overlapping cDNAs encoding a 3.0-kb-long mRNA, Wound Inducible Transcript, 3.0 ( wit 3.0). In situ hybridization demonstrated that wit 3.0 was primarily expressed by the fibroblasts associated with tooth extraction wound-healing. Appearing to generate from the wit 3.0 gene, two alternative transcripts presented, encoding 215-( wit 3.0 α) and 253-( wit 3.0 β) amino-acid-long peptides with the characteristics ...

Journal of periodontal & implant science, 2013

Implant treatment has become the treatment of choice to replace missing teeth in partially edentu... more Implant treatment has become the treatment of choice to replace missing teeth in partially edentulous areas. Dental implants present different biological and biomechanical characteristics than natural teeth. Occlusion is considered to be one of the most important factors contributing to implant success. Most literature on implant occlusal concepts is based on expert opinion, anecdotal experiences, in vitro and animal studies, and only limited clinical research. Furthermore, scientific literature regarding implant occlusion, particularly in implant-supported fixed dental prostheses remains controversial. In this study, the current status of implant occlusion was reviewed and discussed. Further randomized clinical research to investigate the correlation between implant occlusion, the implant success rate, and its risk factors is warranted to determine best clinical practices.

Journal of Bio- and Tribo-Corrosion, 2014

The general requirements for joint replacement devices emphasizes the importance of device materi... more The general requirements for joint replacement devices emphasizes the importance of device material biocompatibility, with no inflammatory or toxic response to wear beyond a tolerable level, the appropriate mechanical properties for the desired application, and lastly economically viable manufacturing and processing methods. Implicit in these requirements is the importance of understanding wear and failure mechanisms of implanted devices. However, compared to orthopedic total joint replacement (TJR) devices, functional wear failure mechanisms for temporomandibular joint (TMJ) TJR implants have not been clearly defined. Our research group has started initial translational investigations involving the analysis of failed retrieved TMJ TJR devices alloy microstructure compared to control, never implanted, TMJ TJR devices utilizing established orthopedic TJR device retrieval tribocorrosion evaluation protocols. This and future studies will guide future material choices and functional design improvements for TMJ TJR devices. Orthopedic TJR implant schemes may also be improved by understanding the degradation mechanism of TMJ TJR implants, as the materials employed in both TJR devices are similar.

Plos One, 2014

Diabetes and infections are associated with a high risk of implant failure. However, the effects ... more Diabetes and infections are associated with a high risk of implant failure. However, the effects of such conditions on the electrochemical stability of titanium materials remain unclear. This study evaluated the corrosion behavior of a Ti-6Al-4V alloy, with a smooth surface or conditioned by double-acid-etching, in simulated body fluid with different concentrations of dextrose and lipopolysaccharide. For the electrochemical assay, the open-circuit-potential, electrochemical impedance spectroscopy, and potentiodynamic test were used. The disc surfaces were characterized by scanning electron microscopy and atomic force microscopy. Their surface roughness and Vickers microhardness were also tested. The quantitative data were analyzed by Pearson's correlation and independent t-tests (a = 0.05). In the corrosion parameters, there was a strong lipopolysaccharide correlation with the I pass (passivation current density), C dl (double-layer capacitance), and R p (polarization resistance) values (p,0.05) for the Ti-6Al-4V alloy with surface treatment by double-acid-etching. The combination of dextrose and lipopolysaccharide was correlated with the I corr (corrosion current density) and I pass (p,0.05). The acid-treated groups showed a significant increase in C dl values and reduced R p values (p,0.05, t-test). According to the topography, there was an increase in surface roughness (R 2 = 0.726, p,0.0001 for the smooth surface; R 2 = 0.405, p = 0.036 for the double-acid-etching-treated surface). The microhardness of the smooth Ti-6Al-4V alloy decreased (p,0.05) and that of the treated Ti-6Al-4V alloy increased (p,0.0001). Atomic force microscopy showed changes in the microstructure of the Ti-6Al-4V alloy by increasing the surface thickness mainly in the group associated with dextrose and lipopolysaccharide. The combination of dextrose and lipopolysaccharide affected the corrosion behavior of the Ti-6Al-4V alloy surface treated with double-acid-etching. However, no dose-response corrosion behavior could be observed. These results suggest a greater susceptibility to corrosion of titanium implants in diabetic patients with associated infections.

Journal of Bio- and Tribo-Corrosion, 2014

Orthopedic and dental implants experience the synergistic effect of wear and corrosion, i.e., tri... more Orthopedic and dental implants experience the synergistic effect of wear and corrosion, i.e., tribocorrosion, which has been a major contributor to the premature failure of implants. This work focuses on the development of a compact and cost-effective tribocorrosion apparatus for the investigation of fretting and wear. The custom-built apparatus is validated with an analysis of the tribocorrosion behavior of Ti-6Al-4V disks in artificial saliva (pH = 6.5, T = 37°C). Electrochemical impedance spectroscopy, potentiodynamic, free potential, and potentiostatic analyses were used for electrochemical characterization of Ti-6Al-4V disks. White light interferometry and scanning electron microscopy were used to analyze wear scars on the Ti-6Al-4V disks. Total wear loss was calculated to be 12.4 ± 1.5 lg, and the synergistic weight loss ratio (0.78 ± 0.1) showed that Ti-6Al-4V disks experience synergy of wear and corrosion, with wear being the dominant component.

International Journal of Nanomedicine, Aug 12, 2014

Abstract: After the implantation of a biomaterial in the body, the first interaction occurs betwe... more Abstract: After the implantation of a biomaterial in the body, the first interaction occurs between the cells in contact with the biomaterial surface. Read this original research and sign up to receive International Journal of Nanomedicine here: http://www.dovepress.com/articles.php?article_id=17885

The purpose of this study was to evaluate the discrepancies between abstracts presented at the IA... more The purpose of this study was to evaluate the discrepancies between abstracts presented at the IADR meeting (2004-2005) and their full-text publication. Material and Methods. Abstracts from the Prosthodontic Section of IADR meeting were obtained. The following information was collected: abstract title, number of authors, study design, statistical analysis, outcome, and funding source. PubMed was used to identify the full-text publication of the abstracts. The discrepancies between the abstract and the full-text publication were examined, categorized as major and minor discrepancies, and quantified. The data were collected and analyzed using descriptive analysis. Frequency and percentage of major and minor discrepancies were calculated. Results. A total of 109 (95.6%) articles showed changes from their abstracts. Seventy-four (65.0%) and 105 (92.0%) publications had at least one major and one minor discrepancies, respectively. Minor discrepancies were more prevalent (92.0%) than major discrepancies (65.0%). The most common minor discrepancy was observed in the title (80.7%), and most common major discrepancies were seen in results (48.2%). Conclusion. Minor discrepancies were more prevalent than major discrepancies. The data presented in this study may be useful to establish a more comprehensive structured abstract requirement for future meetings.

PLoS ONE, 2014

The primary objective of this study was to fabricate a TiO 2 nanotubular surface, which could mai... more The primary objective of this study was to fabricate a TiO 2 nanotubular surface, which could maintain hydrophilicity over time (resist aging). In order to achieve non-aging hydrophilic surfaces, anodization and annealing conditions were optimized. This is the first study to show that anodization and annealing condition affect the stability of surface hydrophilicity. Our results indicate that maintenance of hydrophilicity of the obtained TiO 2 nanotubes was affected by anodization voltage and annealing temperature. Annealing sharply decreased the water contact angle (WCA) of the assynthesized TiO 2 nanotubular surface, which was correlated to improved hydrophilicity. TiO 2 nanotubular surfaces are transformed to hydrophilic surfaces after annealing, regardless of annealing and anodization conditions; however, WCA measurements during aging demonstrate that surface hydrophilicity of non-anodized and 20 V anodized samples decreased after only 11 days of aging, while the 60 V anodized samples maintained their hydrophilicity over the same time period. The nanotubes obtained by 60 V anodization followed by 600 uC annealing maintained their hydrophilicity significantly longer than nanotubes which were obtained by 60 V anodization followed by 300 uC annealing.

Journal of …, 2011

Purpose: The purposes of this study were to describe the demographics of abstracts presented at t... more Purpose: The purposes of this study were to describe the demographics of abstracts presented at the prosthodontics section of IADR General Sessions from 2004 to 2005, evaluate the publication rate of abstracts, and analyze the relationship between variables ...

Journal of Biological …, 2003

Wounds of the oral mucosa show faster closure with less scar formation than skin wounds in other ... more Wounds of the oral mucosa show faster closure with less scar formation than skin wounds in other areas. A differentially expressed cDNA, wound-inducible transcript 3.0 (wit3.0), was isolated from oral mucosal wound in rats (Sukotjo, C., Abanmy, AA, Ogawa, T., and Nishimura, I. ( ...

Objectives: The purpose of the present study was to investigate the early peri-implant soft tissu... more Objectives: The purpose of the present study was to investigate the early peri-implant soft tissue healing on different titanium surface topographies. Material and methods: Titanium implants with smooth or rough surfaces were placed in the extraction site at 1 month after the maxillary first molar extractions of 15 male Sprague-Dawley rats. At 4 and 7 days after implant surgery, the peri-implant oral mucosa was randomly harvested and analyzed for collagen fiber orientation, and expression of extracellular matrix genes. Descriptive and paired t-tests were performed where appropriate (a ¼ 0.05). Results: The laser scanning microscopic analysis of the Sirius red stained peri-implant connective tissue revealed a parallel and uniform collagen fiber orientation along the smooth implant at both 4 and 7 days. In contrast, the collagen fibers of the comparative peri-implant tissue from rough surface implants at 7 days were not arranged in parallel orientation but in an irregular a ''cotton-ball-like.'' The levels of mRNA of types III and XII collagen and transforming growth factor-b1 significantly increased in the smooth implant group compared with the rough implant group at both 4 and 7 days or either one of days. Conclusion: The results of this study suggest that implant surface characteristics may affect early events of soft tissue healing by influencing collagen fiber orientation and expression of key genes for initial healing. n Contributed equally.

Journal of Oral Implantology, 2014

Traditionally, titanium oxide (TiO2) nanotubes (TNTs) are anodized on Ti-6Al-4V alloy (Ti-V) surf... more Traditionally, titanium oxide (TiO2) nanotubes (TNTs) are anodized on Ti-6Al-4V alloy (Ti-V) surfaces with native TiO2 (amorphous TiO2); subsequent heat treatment of anodized surfaces has been observed to enhance cellular response. As-is bulk Ti-V, however, is often subjected to heat treatment, such as thermal oxidation (TO), to improve its mechanical properties. Thermal oxidation treatment of Ti-V at temperatures greater than 200°C and 400°C initiates the formation of anatase and rutile TiO2, respectively, which can affect TNT formation. This study aims at understanding the TNT formation mechanism on Ti-V surfaces with TO-formed TiO2 compared with that on as-is Ti-V surfaces with native oxide. Thermal oxidation–formed TiO2 can affect TNT formation and surface wettability because TO-formed TiO2 is expected to be part of the TNT structure. Surface characterization was carried out with field emission scanning electron microscopy, energy dispersive x-ray spectroscopy, water contact ang...

This clinical report describes the oral rehabilitation of a 15-year-old male patient who was invo... more This clinical report describes the oral rehabilitation of a 15-year-old male patient who was involved in a snowmobile accident and suffered multiple mid-face and mandibular fractures. Consequences of the accident included avulsion of teeth numbers 5 to 10 and 21 to 26, and a significant amount of maxillary and mandibular anterior alveolar bone loss. The patient underwent open reduction and rigid fixation of the fractured left zygoma, comminuted LeFort I maxillary fracture, and left body of the mandible; closed reduction of the bilateral condylar fractures; autologous corticocancellous bone grafting to the maxilla and mandible; implant placement; and prosthesis fabrication. This multidisciplinary approach successfully restored function and esthetics.

Journal of Dental Research, 2000

Collagen XII has been postulated to organize the extracellular matrix (ECM) architecture of dense... more Collagen XII has been postulated to organize the extracellular matrix (ECM) architecture of dense connective tissues such as the periodontal ligament (PDL) and skin. The objective of this study was to test this hypothesis in transgenic mice carrying a dominant interference mutation of collagen XII. The truncated oLl(XII) collagen minigene construct MXIINC3(-), driven by the mouse ox2(I) collagen promoter, was prepared and used to generate transgenic mouse lines. The PDL matrix fibers of molar teeth lost the ordered architecture characteristic of ligament tissue without noticeable inflammation. Cellular cement appeared to be disrupted at the PDL insertion. By confocal laser scanning microscopy, the PDL of transgenic mice demonstrated swollen and irregularly arranged collagen fibers associated with internal porosity. The skin of transgenic mice revealed the lack of matrix fiber structure in the papillary dermis. These results indicated that the dominant interference mutation of collagen XII disorganized the ECM architecture of PDL and skin.

Journal of Dental Research, 2002

Tooth extraction is the most commonly prescribed ablation surgery in dentistry and results in the... more Tooth extraction is the most commonly prescribed ablation surgery in dentistry and results in the formation of edentulous mucosa. Although the edentulous mucosa serves as the critical interfacial tissue for removable and implant-assisted prostheses, the structure and physiology of this wound-induced tissue are largely uninvestigated. We addressed the hypothesis that tooth extraction activates the expression of a unique set of genes in healing edentulous mucosa. Using the Differential Display Polymerase Chain Reaction and 5′ Rapid Amplification of cDNA Ends protocols, we isolated overlapping cDNAs encoding a 3.0-kb-long mRNA, Wound Inducible Transcript, 3.0 ( wit 3.0). In situ hybridization demonstrated that wit 3.0 was primarily expressed by the fibroblasts associated with tooth extraction wound-healing. Appearing to generate from the wit 3.0 gene, two alternative transcripts presented, encoding 215-( wit 3.0 α) and 253-( wit 3.0 β) amino-acid-long peptides with the characteristics ...

Journal of periodontal & implant science, 2013

Implant treatment has become the treatment of choice to replace missing teeth in partially edentu... more Implant treatment has become the treatment of choice to replace missing teeth in partially edentulous areas. Dental implants present different biological and biomechanical characteristics than natural teeth. Occlusion is considered to be one of the most important factors contributing to implant success. Most literature on implant occlusal concepts is based on expert opinion, anecdotal experiences, in vitro and animal studies, and only limited clinical research. Furthermore, scientific literature regarding implant occlusion, particularly in implant-supported fixed dental prostheses remains controversial. In this study, the current status of implant occlusion was reviewed and discussed. Further randomized clinical research to investigate the correlation between implant occlusion, the implant success rate, and its risk factors is warranted to determine best clinical practices.

Journal of Bio- and Tribo-Corrosion, 2014

The general requirements for joint replacement devices emphasizes the importance of device materi... more The general requirements for joint replacement devices emphasizes the importance of device material biocompatibility, with no inflammatory or toxic response to wear beyond a tolerable level, the appropriate mechanical properties for the desired application, and lastly economically viable manufacturing and processing methods. Implicit in these requirements is the importance of understanding wear and failure mechanisms of implanted devices. However, compared to orthopedic total joint replacement (TJR) devices, functional wear failure mechanisms for temporomandibular joint (TMJ) TJR implants have not been clearly defined. Our research group has started initial translational investigations involving the analysis of failed retrieved TMJ TJR devices alloy microstructure compared to control, never implanted, TMJ TJR devices utilizing established orthopedic TJR device retrieval tribocorrosion evaluation protocols. This and future studies will guide future material choices and functional design improvements for TMJ TJR devices. Orthopedic TJR implant schemes may also be improved by understanding the degradation mechanism of TMJ TJR implants, as the materials employed in both TJR devices are similar.

Plos One, 2014

Diabetes and infections are associated with a high risk of implant failure. However, the effects ... more Diabetes and infections are associated with a high risk of implant failure. However, the effects of such conditions on the electrochemical stability of titanium materials remain unclear. This study evaluated the corrosion behavior of a Ti-6Al-4V alloy, with a smooth surface or conditioned by double-acid-etching, in simulated body fluid with different concentrations of dextrose and lipopolysaccharide. For the electrochemical assay, the open-circuit-potential, electrochemical impedance spectroscopy, and potentiodynamic test were used. The disc surfaces were characterized by scanning electron microscopy and atomic force microscopy. Their surface roughness and Vickers microhardness were also tested. The quantitative data were analyzed by Pearson's correlation and independent t-tests (a = 0.05). In the corrosion parameters, there was a strong lipopolysaccharide correlation with the I pass (passivation current density), C dl (double-layer capacitance), and R p (polarization resistance) values (p,0.05) for the Ti-6Al-4V alloy with surface treatment by double-acid-etching. The combination of dextrose and lipopolysaccharide was correlated with the I corr (corrosion current density) and I pass (p,0.05). The acid-treated groups showed a significant increase in C dl values and reduced R p values (p,0.05, t-test). According to the topography, there was an increase in surface roughness (R 2 = 0.726, p,0.0001 for the smooth surface; R 2 = 0.405, p = 0.036 for the double-acid-etching-treated surface). The microhardness of the smooth Ti-6Al-4V alloy decreased (p,0.05) and that of the treated Ti-6Al-4V alloy increased (p,0.0001). Atomic force microscopy showed changes in the microstructure of the Ti-6Al-4V alloy by increasing the surface thickness mainly in the group associated with dextrose and lipopolysaccharide. The combination of dextrose and lipopolysaccharide affected the corrosion behavior of the Ti-6Al-4V alloy surface treated with double-acid-etching. However, no dose-response corrosion behavior could be observed. These results suggest a greater susceptibility to corrosion of titanium implants in diabetic patients with associated infections.

Journal of Bio- and Tribo-Corrosion, 2014

Orthopedic and dental implants experience the synergistic effect of wear and corrosion, i.e., tri... more Orthopedic and dental implants experience the synergistic effect of wear and corrosion, i.e., tribocorrosion, which has been a major contributor to the premature failure of implants. This work focuses on the development of a compact and cost-effective tribocorrosion apparatus for the investigation of fretting and wear. The custom-built apparatus is validated with an analysis of the tribocorrosion behavior of Ti-6Al-4V disks in artificial saliva (pH = 6.5, T = 37°C). Electrochemical impedance spectroscopy, potentiodynamic, free potential, and potentiostatic analyses were used for electrochemical characterization of Ti-6Al-4V disks. White light interferometry and scanning electron microscopy were used to analyze wear scars on the Ti-6Al-4V disks. Total wear loss was calculated to be 12.4 ± 1.5 lg, and the synergistic weight loss ratio (0.78 ± 0.1) showed that Ti-6Al-4V disks experience synergy of wear and corrosion, with wear being the dominant component.

International Journal of Nanomedicine, Aug 12, 2014

Abstract: After the implantation of a biomaterial in the body, the first interaction occurs betwe... more Abstract: After the implantation of a biomaterial in the body, the first interaction occurs between the cells in contact with the biomaterial surface. Read this original research and sign up to receive International Journal of Nanomedicine here: http://www.dovepress.com/articles.php?article_id=17885

The purpose of this study was to evaluate the discrepancies between abstracts presented at the IA... more The purpose of this study was to evaluate the discrepancies between abstracts presented at the IADR meeting (2004-2005) and their full-text publication. Material and Methods. Abstracts from the Prosthodontic Section of IADR meeting were obtained. The following information was collected: abstract title, number of authors, study design, statistical analysis, outcome, and funding source. PubMed was used to identify the full-text publication of the abstracts. The discrepancies between the abstract and the full-text publication were examined, categorized as major and minor discrepancies, and quantified. The data were collected and analyzed using descriptive analysis. Frequency and percentage of major and minor discrepancies were calculated. Results. A total of 109 (95.6%) articles showed changes from their abstracts. Seventy-four (65.0%) and 105 (92.0%) publications had at least one major and one minor discrepancies, respectively. Minor discrepancies were more prevalent (92.0%) than major discrepancies (65.0%). The most common minor discrepancy was observed in the title (80.7%), and most common major discrepancies were seen in results (48.2%). Conclusion. Minor discrepancies were more prevalent than major discrepancies. The data presented in this study may be useful to establish a more comprehensive structured abstract requirement for future meetings.

PLoS ONE, 2014

The primary objective of this study was to fabricate a TiO 2 nanotubular surface, which could mai... more The primary objective of this study was to fabricate a TiO 2 nanotubular surface, which could maintain hydrophilicity over time (resist aging). In order to achieve non-aging hydrophilic surfaces, anodization and annealing conditions were optimized. This is the first study to show that anodization and annealing condition affect the stability of surface hydrophilicity. Our results indicate that maintenance of hydrophilicity of the obtained TiO 2 nanotubes was affected by anodization voltage and annealing temperature. Annealing sharply decreased the water contact angle (WCA) of the assynthesized TiO 2 nanotubular surface, which was correlated to improved hydrophilicity. TiO 2 nanotubular surfaces are transformed to hydrophilic surfaces after annealing, regardless of annealing and anodization conditions; however, WCA measurements during aging demonstrate that surface hydrophilicity of non-anodized and 20 V anodized samples decreased after only 11 days of aging, while the 60 V anodized samples maintained their hydrophilicity over the same time period. The nanotubes obtained by 60 V anodization followed by 600 uC annealing maintained their hydrophilicity significantly longer than nanotubes which were obtained by 60 V anodization followed by 300 uC annealing.

Journal of …, 2011

Purpose: The purposes of this study were to describe the demographics of abstracts presented at t... more Purpose: The purposes of this study were to describe the demographics of abstracts presented at the prosthodontics section of IADR General Sessions from 2004 to 2005, evaluate the publication rate of abstracts, and analyze the relationship between variables ...

Journal of Biological …, 2003

Wounds of the oral mucosa show faster closure with less scar formation than skin wounds in other ... more Wounds of the oral mucosa show faster closure with less scar formation than skin wounds in other areas. A differentially expressed cDNA, wound-inducible transcript 3.0 (wit3.0), was isolated from oral mucosal wound in rats (Sukotjo, C., Abanmy, AA, Ogawa, T., and Nishimura, I. ( ...

Objectives: The purpose of the present study was to investigate the early peri-implant soft tissu... more Objectives: The purpose of the present study was to investigate the early peri-implant soft tissue healing on different titanium surface topographies. Material and methods: Titanium implants with smooth or rough surfaces were placed in the extraction site at 1 month after the maxillary first molar extractions of 15 male Sprague-Dawley rats. At 4 and 7 days after implant surgery, the peri-implant oral mucosa was randomly harvested and analyzed for collagen fiber orientation, and expression of extracellular matrix genes. Descriptive and paired t-tests were performed where appropriate (a ¼ 0.05). Results: The laser scanning microscopic analysis of the Sirius red stained peri-implant connective tissue revealed a parallel and uniform collagen fiber orientation along the smooth implant at both 4 and 7 days. In contrast, the collagen fibers of the comparative peri-implant tissue from rough surface implants at 7 days were not arranged in parallel orientation but in an irregular a ''cotton-ball-like.'' The levels of mRNA of types III and XII collagen and transforming growth factor-b1 significantly increased in the smooth implant group compared with the rough implant group at both 4 and 7 days or either one of days. Conclusion: The results of this study suggest that implant surface characteristics may affect early events of soft tissue healing by influencing collagen fiber orientation and expression of key genes for initial healing. n Contributed equally.

Journal of Oral Implantology, 2014

Traditionally, titanium oxide (TiO2) nanotubes (TNTs) are anodized on Ti-6Al-4V alloy (Ti-V) surf... more Traditionally, titanium oxide (TiO2) nanotubes (TNTs) are anodized on Ti-6Al-4V alloy (Ti-V) surfaces with native TiO2 (amorphous TiO2); subsequent heat treatment of anodized surfaces has been observed to enhance cellular response. As-is bulk Ti-V, however, is often subjected to heat treatment, such as thermal oxidation (TO), to improve its mechanical properties. Thermal oxidation treatment of Ti-V at temperatures greater than 200°C and 400°C initiates the formation of anatase and rutile TiO2, respectively, which can affect TNT formation. This study aims at understanding the TNT formation mechanism on Ti-V surfaces with TO-formed TiO2 compared with that on as-is Ti-V surfaces with native oxide. Thermal oxidation–formed TiO2 can affect TNT formation and surface wettability because TO-formed TiO2 is expected to be part of the TNT structure. Surface characterization was carried out with field emission scanning electron microscopy, energy dispersive x-ray spectroscopy, water contact ang...

This clinical report describes the oral rehabilitation of a 15-year-old male patient who was invo... more This clinical report describes the oral rehabilitation of a 15-year-old male patient who was involved in a snowmobile accident and suffered multiple mid-face and mandibular fractures. Consequences of the accident included avulsion of teeth numbers 5 to 10 and 21 to 26, and a significant amount of maxillary and mandibular anterior alveolar bone loss. The patient underwent open reduction and rigid fixation of the fractured left zygoma, comminuted LeFort I maxillary fracture, and left body of the mandible; closed reduction of the bilateral condylar fractures; autologous corticocancellous bone grafting to the maxilla and mandible; implant placement; and prosthesis fabrication. This multidisciplinary approach successfully restored function and esthetics.

Journal of Dental Research, 2000

Collagen XII has been postulated to organize the extracellular matrix (ECM) architecture of dense... more Collagen XII has been postulated to organize the extracellular matrix (ECM) architecture of dense connective tissues such as the periodontal ligament (PDL) and skin. The objective of this study was to test this hypothesis in transgenic mice carrying a dominant interference mutation of collagen XII. The truncated oLl(XII) collagen minigene construct MXIINC3(-), driven by the mouse ox2(I) collagen promoter, was prepared and used to generate transgenic mouse lines. The PDL matrix fibers of molar teeth lost the ordered architecture characteristic of ligament tissue without noticeable inflammation. Cellular cement appeared to be disrupted at the PDL insertion. By confocal laser scanning microscopy, the PDL of transgenic mice demonstrated swollen and irregularly arranged collagen fibers associated with internal porosity. The skin of transgenic mice revealed the lack of matrix fiber structure in the papillary dermis. These results indicated that the dominant interference mutation of collagen XII disorganized the ECM architecture of PDL and skin.