Maria J Troulis

Publications of Maria J Troulis

• Minipig Model of Maxillary Distraction Osteogenesis: Immunohistochemical and Histomorphometric Analysis of the Sequence of Osteogenesis.

  Authors: Maria E Papadaki, Leonard B Kaban, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 04/2012;

  PURPOSE: To document the sequence of bone formation in a minipig model of Le Fort I distraction osteogenesis (DO) using immunohistochemistry and histomorphometry. MATERIALS AND METHODS: FemalePURPOSE: To document the sequence of bone formation in a minipig model of Le Fort I distraction osteogenesis (DO) using immunohistochemistry and histomorphometry. MATERIALS AND METHODS: Female Yucatan minipigs (N = 9) in the mixed-dentition stage underwent bilateral maxillary DO. The distraction protocol was 0 days of latency, with a distraction rate of 1 mm/d for 12 days and 24 days of fixation. Specimens were harvested and divided between the central incisors (18 hemi-maxillae) at the end of DO (n = 6), at mid-fixation (n = 6), and at the end of fixation (n = 6). Sections, including the advancement zone, were stained with hematoxylin-eosin, collagen II, CD34, proliferating cell nuclear antigen, and tartrate-resistant acid phosphatase. Light and fluorescence microscope images (original magnification ×200) were obtained, and percentage of surface area (PSA) of the advancement zone occupied by fibrous tissue, vessels, proliferating cells, osteoid, and bone was determined. An intact maxilla served as the control. RESULTS: At the end of DO, in the advancement zone, the PSA (mean values) of proliferating cells was 33.16%; fibrous tissue, 52%; vessels, 4.35%; and new bone, 5.45%. At the end of fixation, the PSA of proliferating cells decreased to 10.53%, fibrous tissue to 2.3%, and vessels to 1.5% whereas the PSA of new bone increased to 44.9%. CONCLUSIONS: The results of this study indicate that the progression of osteogenesis in the maxillary DO wound begins with intense cellular proliferation and vascular fibrous tissue formation and progresses to mature, cancellous bone by the end of fixation. The PSA occupied by mature bone is significantly less than in the control maxilla at the end of fixation. This is consistent with the sequence in the mandibular DO wound.

• Three-Dimensionally Printed Polycaprolactone and β-Tricalcium Phosphate Scaffolds for Bone Tissue Engineering: An In Vitro Study.

  Authors: Basel Sharaf, Caroline B Faris, Harutsugi Abukawa, Srinivas M Susarla, Joseph P Vacanti, Leonard B Kaban, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 11/2011; 70(3):647-56.

  The purpose of this study was to evaluate porcine bone marrow-derived progenitor cell (pBMPC) proliferation and penetration into a novel 3-dimensionally printed scaffold. Four different tissueThe purpose of this study was to evaluate porcine bone marrow-derived progenitor cell (pBMPC) proliferation and penetration into a novel 3-dimensionally printed scaffold. Four different tissue engineering scaffolds to evaluate pBMPC proliferation and penetration were examined. Scaffolds were fabricated from polycaprolactone (PCL) or the combination of β-tricalcium phosphate (β-TCP) and PCL (50:50), with 2 separate channel sizes (1 mm [small (S)] vs 2 mm [large (L)]). Scaffolds were fabricated into 20 × 20 × 7-mm blocks by use of a TheriForm machine (Integra Life Sciences, Akron, OH). Four groups of scaffolds were examined for pBMPC proliferation and penetration: group 1, β-TCP/PCL S; group 2, β-TCP/PCL L; group 3, PCL S; and group 4, PCL L. Nonparametric mean (Kruskal-Wallis) and multiple comparisons tests were used to compare the 4 groups. No shrinkage or deformation was noted in any of the scaffold groups after 2 weeks of culture. Mean surface cell counts ranged from 13.4 to 87.8 cells/0.57 mm(2), with group 1 (β-TCP/PCL S) having statistically significantly higher counts than the other groups (P < .001). Mean interior cell counts ranged from 10.9 to 75.6 cells/0.57 mm(2), with group 1 having the greatest interior cell count (P < .001). Total collagen formation ranged from 0.2% to 86%, with group 1 having the highest collagen formation (P < .001). The 3-dimensionally printed scaffold (β-TCP/PCL) with 1-mm channels showed greater cellular proliferation, penetration, and collagen formation after a 2-week in vitro culture than the other scaffolds evaluated. β-TCP/PCL S scaffolds warrant further evaluation for bone tissue engineering in vivo.

• Automated continuous mandibular distraction osteogenesis: review of the literature.

  Authors: Batya R Goldwaser, Maria E Papadaki, Leonard B Kaban, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 06/2011; 70(2):407-16.

  Current devices for mandibular distraction osteogenesis (DO) are complex and require significant patient or family skill during active distraction. Successful development of an automated, continuousCurrent devices for mandibular distraction osteogenesis (DO) are complex and require significant patient or family skill during active distraction. Successful development of an automated, continuous distraction device would eliminate the need for patient participation in this process. The purpose of this study was to comprehensively review devices currently in development for continuous DO and to identify and evaluate the achieved successes and remaining problems. A PubMed search of the English language literature in October 2008 using the keywords automatic or automated or continuous or hydraulic or motor or magnetic or spring and distraction osteogenesis was performed. The search included all technical notes, animal studies, and human studies describing the use of any automated continuous distraction device for the mandible. Excluded were studies using distraction devices employing hydraulics, motors, or springs that did not distract automatically and continuously and devices used for bones other than the mandible. The search returned 97 matches. Of these, 12 articles were selected as relevant to this review based on the inclusion and exclusion criteria detailed above. Eight distinct devices for automated, continuous DO were described in these reports and evaluated in this review. These included motor-driven, spring-mediated, and hydraulically powered distractors. The abundance of research currently underway to develop a continuous distractor highlights the clinical demand for, and usefulness, of such a device. Despite many advances and promising results, significant problems remain to be overcome before any of these devices gain widespread clinical acceptance.

• Serial histologic and immunohistochemical changes in anterior digastric myocytes in response to distraction osteogenesis.

  Authors: Matthew E Lawler, Gentry M Hansen, W Bradford Williams, Srinivas M Susarla, William C Faquin, Maria J Troulis, Leonard B Kaban

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 05/2011; 70(1):168-78.

  To document histologic and immunohistochemical changes in the anterior digastric muscle during distraction osteogenesis (DO). Nineteen Yucatan minipigs with mixed dentition were used for theseTo document histologic and immunohistochemical changes in the anterior digastric muscle during distraction osteogenesis (DO). Nineteen Yucatan minipigs with mixed dentition were used for these experiments. Group A (n = 16) underwent unilateral mandibular distraction at a rate of 1 mm/day (no latency) for 12 days. Animals were killed at mid-DO (n = 5), end-DO (n = 5), mid-fixation (n = 4), and end-fixation (n = 2). Group B (n = 2) underwent acute 12-mm advancement, and group C (n = 1) dissection and osteotomy. Animals from groups B and C were killed at the end-DO time point. Digastric muscles from treatment and contralateral sides of all animals were harvested and embedded in paraffin. Specimens were stained with hematoxylin/eosin or immunohistochemically for proliferating cell nuclear antigen (PCNA; total cell proliferation), paired Box-7 gene protein (Pax7; satellite cells), or myogenic differentiation 1 protein (MyoD; differentiating myoblasts). Descriptive and bivariate statistics were computed to compare groups (P ≤ .05 statistically significant). All animals survived the operation and observation period; there were no device failures. Two animals (1 at mid-DO, 1 at mid-fixation) were eliminated from the study because of postoperative infection. There was minimal digastric inflammation, fibrosis, and muscle fiber size variability during active DO. Immunohistochemical analysis showed statistically significant increases in PCNA (cellular proliferation), Pax7 (satellite cells), and MyoD (differentiating myoblasts) positive nuclei in digastrics at mid-DO and end-DO. Results of this study indicate that there are minimal pathologic changes but significant increases in PCNA, Pax7, and MyoD positive nuclei during active distraction. This supports the hypothesis that the digastric muscle response to DO consists of proliferation and hypertrophy.

• A minipig model of maxillary distraction osteogenesis.

  Authors: Maria E Papadaki, Maria J Troulis, Julie Glowacki, Leonard B Kaban

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 11/2010; 68(11):2783-91.

  To establish a porcine model for maxillary distraction osteogenesis and to document the sequence of bone formation in the zone of advancement. Female Yucatan minipigs (n = 9) in the mixed dentitionTo establish a porcine model for maxillary distraction osteogenesis and to document the sequence of bone formation in the zone of advancement. Female Yucatan minipigs (n = 9) in the mixed dentition stage underwent modified Le Fort I osteotomy through a vestibular incision under general anesthesia. A unidirectional, semiburied Le Fort I distraction device was fixed across the osteotomy. The distraction protocol was 0-day latency, 1-mm/d rate for 12 days, and 24 days of fixation. Maxillary specimens (n = 9) were harvested and divided in half at the end of distraction (n = 6 sides), midfixation (n = 6), and the end of fixation (n = 6). Clinical stability, volume, and radiographic density across the zone of advancement were graded on semiquantitative scales. Specimens were stained with hematoxylin and eosin and examined with light microscopy. Animals tolerated the operation, the distraction and fixation periods. There were no infections and no devices failed. At the end of the distraction period, bone trabeculae were present at the periphery and fibrous tissues, and vessels, preosteoblasts, and osteoblasts were present in the center of the zone of advancement. Islands of chondrocyte-like cells appeared in 1 specimen each at midfixation and the end of fixation. At the end of fixation, clinical stability and radiographic density were graded 3/3 and bone formation was complete across the advancement zone in all specimens. A model for Le Fort I distraction osteogenesis was established. Intramembranous bone formation was the predominant mechanism of healing in the zone of advancement. Latency was not necessary for bone formation in this minipig model.

• Histomorphometric analysis of the porcine mandibular distraction wound.

  Authors: Matthew E Lawler, Fardad T Tayebaty, W Bradford Williams, Maria J Troulis, Leonard B Kaban

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 07/2010; 68(7):1543-54.

  To analyze the sequence of histomorphometric changes in the regenerate during distraction osteogenesis (DO) of the minipig mandible. A total of 16 minipigs underwent unilateral mandibular DO using aTo analyze the sequence of histomorphometric changes in the regenerate during distraction osteogenesis (DO) of the minipig mandible. A total of 16 minipigs underwent unilateral mandibular DO using a protocol of 0-day latency and a 1-mm/day rate for 12 days, and 24 days of fixation. The mandibles were harvested at mid-DO, end-DO, mid-fixation, and end-fixation. An additional 2 minipigs underwent acute lengthening, and 1 sham control was included. Serial gross examinations and plain radiographs were performed before paraffin embedding. The sections were stained with hematoxylin-eosin or hematoxylin/alcian blue/sirius red stain. Histomorphometric analysis was performed to determine the percentage of surface area (PSA) occupied by hematoma, fibrous tissue, cartilage, and bone. All 19 minipigs survived the operation, and 17 survived the observation period; 2 were killed because of infection (mid-DO, n = 1 and end-fixation, n = 1). No device failures occurred. Of the 17 specimens, 4 were at mid-DO, 4 at end-DO, 4 at mid-fixation, and 2 at end-fixation; 2 were in the acute lengthening group, and 1 was the sham control. Hematoma was present only at mid-DO (16.61 +/- 8.07 PSA) and end-DO (1.17 +/- 2.33 PSA). Fibrous tissue decreased from mid-DO (53.12 +/- 8.59 PSA) to end-fixation (25.00 +/- 0.83 PSA). Cartilage was present in end-DO (1.72 +/- 2.71 PSA), mid-fixation (5.82 +/- 6.64 PSA), and acute lengthening (1.43 +/- 0.95 PSA). Bone increased from mid-DO (25.18 +/- 0.99 PSA) to end-fixation (64.89 +/- 0.79 PSA) and occurred earlier in the superior and middle thirds of the wounds. Periosteal bone formation predominated over endosteal bone formation early in distraction. The results of the present study indicate that bone formation in this model consists of both intramembranous and endochondral components, with intramembranous osteogenesis predominating. Bone formation occurred earlier in the superior/middle portions of the wound, possibly owing to osteoinductive properties of developing tooth buds and the inferior alveolar nerve, respectively.

• Management of obstructive sleep apnea: role of distraction osteogenesis.

  Authors: Carl Bouchard, Maria J Troulis, Leonard B Kaban

  Oral and maxillofacial surgery clinics of North America. 11/2009; 21(4):459-75.

  Distraction osteogenesis to expand the facial skeleton is an alternative to standard orthognathic surgery for selected patients with obstructive sleep apnea. For children with congenital micrognathiaDistraction osteogenesis to expand the facial skeleton is an alternative to standard orthognathic surgery for selected patients with obstructive sleep apnea. For children with congenital micrognathia or midface hypoplasia, distraction osteogenesis allows large advancements without the need for bone grafting and with less risk of relapse. For later-onset obstructive sleep apnea, distraction osteogenesis may represent an alternative when acute bone movement is expected to be difficult (scarring from previous surgery or radiation therapy) or when the risk for inferior alveolar nerve damage is unacceptable (patients older than 40 years).

• Effect of ibuprofen on osteoblast differentiation of porcine bone marrow-derived progenitor cells.

  Authors: Harutsugi Abukawa, Maynard Phelps, Pamela Jackson, R Malcolm Smith, Joseph P Vacanti, Leonard B Kaban, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 11/2009; 67(11):2412-7.

  PURPOSE: Nonsteroidal anti-inflammatory drugs are commonly prescribed to reduce inflammation and pain. However, little is known about the direct effect of these drugs on the differentiation of bonePURPOSE: Nonsteroidal anti-inflammatory drugs are commonly prescribed to reduce inflammation and pain. However, little is known about the direct effect of these drugs on the differentiation of bone marrow-derived progenitor cells into osteoblasts. The purpose of this study was to determine the effect of ibuprofen on osteoblast differentiation and proliferation in a minipig model. MATERIALS AND METHODS: Bone marrow was aspirated from the minipig ilium, and porcine bone marrow-derived progenitor cells (pBMPCs) were isolated and expanded in standard culture medium. The pBMPCs were replated and differentiated into osteoblasts by use of osteogenic supplements (OS). Five groups were studied: negative control--pBMPCs in standard medium only; positive control--pBMPCs, standard culture medium, and OS; and 3 experimental groups--pBMPCs, standard culture medium, OS, and ibuprofen added in doses of 0.1, 1.0, and 3.0 mmol/L. Cell cultures were evaluated quantitatively by alkaline phosphatase (ALP) stain, von Kossa stain, and deoxyribonucleic acid (DNA) content. RESULTS: pBMPCs cultured with OS and low-dose ibuprofen (0.1 mmol/L) showed ALP stain, von Kossa stain, and DNA content similar to pBMPCs cultured in OS (positive control). pBMPCs cultured in higher doses of ibuprofen (1.0 and 3.0 mmol/L) produced significantly less positive staining of ALP and von Kossa and decreased DNA content. CONCLUSION: The results indicate that high-dose ibuprofen has a deleterious effect on pBMPC differentiation into osteoblasts whereas low-dose ibuprofen does not. The low dose of 0.1 mmol/L is the typical serum level when prescribed for clinical use.

• A protocol for management of temporomandibular joint ankylosis in children.

  Authors: Leonard B Kaban, Carl Bouchard, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 10/2009; 67(9):1966-78.

  Temporomandibular joint (TMJ) ankylosis in children is a challenging problem. Surgical correction is technically difficult and the incidence of recurrence after treatment is high. The purpose of theTemporomandibular joint (TMJ) ankylosis in children is a challenging problem. Surgical correction is technically difficult and the incidence of recurrence after treatment is high. The purpose of the present report is to describe the protocol currently used at the Massachusetts General Hospital for the management of TMJ ankylosis in children. It has been our observation that the most common cause of treatment failure is inadequate resection of the ankylotic mass and failure to achieve adequate passive maximal opening in the operating room. The 7-step protocol consists of 1) aggressive excision of the fibrous and/or bony ankylotic mass, 2) coronoidectomy on the affected side, 3) coronoidectomy on the contralateral side, if steps 1 and 2 do not result in a maximal incisal opening greater than 35 mm or to the point of dislocation of the unaffected TMJ, 4) lining of the TMJ with a temporalis myofascial flap or the native disc, if it can be salvaged, 5) reconstruction of the ramus condyle unit with either distraction osteogenesis or costochondral graft and rigid fixation, and 6) early mobilization of the jaw. If distraction osteogenesis is used to reconstruct the ramus condyle unit, mobilization begins the day of the operation. In patients who undergo costochondral graft reconstruction, mobilization begins after 10 days of maxillomandibular fixation. Finally (step 7), all patients receive aggressive physiotherapy. A case series of children with ankylosis treated using this protocol is presented.

• Clinical application of curvilinear distraction osteogenesis for correction of mandibular deformities.

  Authors: Leonard B Kaban, Edward B Seldin, Ron Kikinis, Krishna Yeshwant, Bonnie L Padwa, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 06/2009; 67(5):996-1008.

  PURPOSE: To report the use of a semiburied curvilinear distraction device, with a 3-dimensional (3D) computed tomography treatment planning system, for correction of mandibular deformities. MATERIALSPURPOSE: To report the use of a semiburied curvilinear distraction device, with a 3-dimensional (3D) computed tomography treatment planning system, for correction of mandibular deformities. MATERIALS AND METHODS: This was a retrospective evaluation of 13 consecutive patients, with syndromic and nonsyndromic micrognathia, who underwent correction by curvilinear distraction osteogenesis. A 3D computed tomography scan was obtained for each patient and imported into a 3D treatment planning system (Slicer/Osteoplan). Surgical guides were constructed to localize the osteotomy and to drill holes to secure the distractor's proximal and distal footplates to the mandible. Postoperatively, patients were followed by clinical examination and plain radiographs to ensure the desired vector of movement. At end distraction, when possible, a 3D computed tomography scan was obtained to document the final mandibular position. RESULTS: Of the 13 patients, 8 were females and 5 were males, with a mean age of 11.9 years (range 15 months to 39 years). All 13 underwent bilateral mandibular curvilinear distraction. Of the 13 patients, 8 were 16 years old or younger and 5 were younger than 6 years of age. The diagnoses included Treacher Collins syndrome (n = 3), Nager syndrome (n = 3), craniofacial microsomia (n = 2), post-traumatic ankylosis (n = 1), and micrognathia (syndromic, n = 3; nonsyndromic, n = 1). The correct distractor placement, vector of movement, and final mandibular position were achieved in 10 of 13 patients. In the other 3 patients, the desired jaw position was achieved by "molding" the regenerate. CONCLUSIONS: The use of a semiburied curvilinear distraction device, with 3D treatment planning, is a potentially powerful tool to correct complex mandibular deformities.

• Minimally invasive orthognathic surgery.

  Authors: Cory M Resnick, Leonard B Kaban, Maria J Troulis

  Facial plastic surgery : FPS. 03/2009; 25(1):49-62.

  Minimally invasive surgery is defined as the discipline in which operative procedures are performed in novel ways to diminish the sequelae of standard surgical dissections. The goals of minimallyMinimally invasive surgery is defined as the discipline in which operative procedures are performed in novel ways to diminish the sequelae of standard surgical dissections. The goals of minimally invasive surgery are to reduce tissue trauma and to minimize bleeding, edema, and injury, thereby improving the rate and quality of healing. In orthognathic surgery, there are two minimally invasive techniques that can be used separately or in combination: (1) endoscopic exposure and (2) distraction osteogenesis. This article describes the historical developments of the fields of orthognathic surgery and minimally invasive surgery, as well as the integration of the two disciplines. Indications, techniques, and the most current outcome data for specific minimally invasive orthognathic surgical procedures are presented.

• Reconstructing mandibular defects using autologous tissue-engineered tooth and bone constructs.

  Authors: Harutsugi Abukawa, Weibo Zhang, Conan S Young, Rose Asrican, Joseph P Vacanti, Leonard B Kaban, Maria J Troulis, Pamela C Yelick

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 03/2009; 67(2):335-47.

  PURPOSE: Current strategies for jaw reconstruction require multiple operations to replace bone and teeth. To improve on these methods, we investigated simultaneous mandibular and toothPURPOSE: Current strategies for jaw reconstruction require multiple operations to replace bone and teeth. To improve on these methods, we investigated simultaneous mandibular and tooth reconstruction, using a Yucatan minipig model. MATERIALS AND METHODS: Tooth and bone constructs were prepared from third molar tooth tissue and iliac-crest bone marrow-derived osteoblasts isolated from, and implanted back into, the same pig as an autologous reconstruction. Implants were harvested after 12 and 20 weeks and evaluated by x-ray, ultrahigh-resolution volume computed tomographic (VCT), histological, and immunohistochemical analyses. RESULTS: Small tooth structures were identified, and consisted of organized dentin, enamel, pulp, and periodontal ligament tissues, surrounded by new bone. No dental tissues formed in implants without tooth-bud cells, and bone regeneration was observed to a limited extent. Immunohistochemical analyses using tooth-specific and bone-specific antibodies confirmed the identity of regenerated tissues. CONCLUSIONS: This pilot study supports the feasibility of tissue-engineering approaches for coordinated autologous tooth and mandible reconstruction, and provides a basis for future improvement of this technique for eventual clinical use in humans.

• Automating skeletal expansion: An implant for distraction osteogenesis of the mandible.

  Authors: John C Magill, Marten F Byl, Batya Goldwaser, Maria Papadaki, Roger Kromann, Brent Yates, Joseph R Morency, Leonard B Kaban, Maria J Troulis

  Journal of medical devices. 03/2009; 3(1):14502.

  BACKGROUND: Distraction osteogenesis (DO) is a technique of bone lengthening that makes use of the body's natural healing capacity. An osteotomy is created and a rigid distraction device is attachedBACKGROUND: Distraction osteogenesis (DO) is a technique of bone lengthening that makes use of the body's natural healing capacity. An osteotomy is created and a rigid distraction device is attached to the bone. After a latency period, the device is activated 2-4 times per day for a total of 1 mm/day of bone lengthening. This technique is used to correct a variety of congenital and acquired deformities of the mandible, midface and long bones. To shorten the treatment period and to eliminate the complications of patient activation of the device, an automated continuous distraction device would be desirable. It has been reported that continuous distraction generates adequate bone with lengthening at a rate of 2 mm/day, thereby reducing the treatment time. METHOD OF APPROACH: The device we describe here uses miniature high-pressure hydraulics, position feedback, and a digital controller to achieve closed-loop control of the distraction process. The implanted actuator can produce up to 40N of distraction force on linear trajectories as well as curved distraction paths. In the paper we detail the spring-powered hydraulic reservoir, controller, and user interface. RESULTS: Experiments to test the new device design were performed in a porcine cadaver head and in live pigs. In the cadaver head, the device performed an 11-day/11 mm distraction with a root-mean-squared position error of 0.09 mm. The device functioned for periods of several days in each of five live animals, though some component failures occurred, leading to design revisions. CONCLUSIONS: The test series showed that the novel design of this system provides the capabilities necessary to automate distraction of the mandible. Further developments will focus on making the implanted position sensor more robust and then carrying out clinical trials.

• Tissue engineered hybrid tooth-bone constructs.

  Authors: Weibo Zhang, Harutsugi Abukawa, Maria J Troulis, Leonard B Kaban, Joseph P Vacanti, Pamela C Yelick

  Methods (San Diego, Calif.). 11/2008;

  Proper rehabilitation of craniofacial defects is challenging because of the complexity of the anatomy and the component tissue types. The ability to simultaneously coordinate the regeneration ofProper rehabilitation of craniofacial defects is challenging because of the complexity of the anatomy and the component tissue types. The ability to simultaneously coordinate the regeneration of multiple tissues would make reconstruction more efficient and might reduce morbidity and improve outcomes. The craniofacial complex is unique because of the presence of teeth, in addition to skin, bone, cartilage, muscle, vascular, and neural tissues since teeth naturally grow in coordination with the craniofacial skeleton, our group developed an autologous, tooth-bone hybrid model to facilitate repair of mandibular defects in the Yucatan minipig. The hybrid tooth-bone construct was prepared by combining tooth bud cell-seeded scaffolds with autologous iliac crest bone marrow derived stem cell-seeded scaffolds, which were transplanted back into surgically created mandibular defects in the same minipig. The constructs were harvested after 12 and 20 weeks of growth. The resulting bone/tooth constructs were evaluated by X-ray, ultra high-resolution volume computed tomography (VCT), histological, immunohistochemical analyses, and transmission electron microscopy (TEM). The observed formation of small tooth-like structures consisting of organized dentin, enamel, pulp, cementum, periodontal ligament, and surrounded by regenerated alveolar bone, suggests the feasibility for regeneration of teeth and associated alveolar bone, in a single procedure. This model provides an accessible method for future clinical applications in humans.

• Craniofacial and temporal bone CT findings in cleidocranial dysplasia.

  Authors: Guido E Gonzalez, Paul A Caruso, Juan E Small, Robert W Jyung, Maria J Troulis, Hugh D Curtin

  Pediatric radiology. 09/2008; 38(8):892-7.

  Cleidocranial dysplasia (CCD) is a multistructural polyostotic genetic disorder that results from mutation of the CBFA1 gene. Hearing loss is a frequent finding in CCD. We describe the CTCleidocranial dysplasia (CCD) is a multistructural polyostotic genetic disorder that results from mutation of the CBFA1 gene. Hearing loss is a frequent finding in CCD. We describe the CT craniofacial findings in CCD and provide a comprehensive discussion of the CT temporal bone findings in these patients.

• Interventional sialoendoscopy: early clinical results.

  Authors: Maria E Papadaki, Joseph P McCain, King Kim, Ronald L Katz, Leonard B Kaban, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 06/2008; 66(5):954-62.

  PURPOSE: Sialoendoscopy is a novel minimally invasive technique to explore the salivary duct system and to treat obstructive salivary disease. This article describes the early clinical experiencePURPOSE: Sialoendoscopy is a novel minimally invasive technique to explore the salivary duct system and to treat obstructive salivary disease. This article describes the early clinical experience with endoscopic salivary duct exploration and sialolithectomy in 2 medical centers. PATIENTS AND METHODS: This is a retrospective case series of 94 patients, with submandibular (n = 77) or parotid (n = 17) sialadenitis secondary to sialolithiasis, strictures, or mucous plugs. Patients underwent sialoendoscopy at Baptist Hospital, Miami (n = 52) or at Massachusetts General Hospital, Boston (n = 42). Dilatation of the duct through the natural orifice was accomplished with salivary dilators. Three endoscope systems with diameters from 1.1 to 2.3 mm were used. Using a basket, grasper, lithotripsy, laser, or a combination of these, stones were fragmented or removed endoscopically. Strictures were dilated and mucous plugs removed. All cases were carried out under general anesthesia. RESULTS: Salivary duct navigation was accomplished in 91/94 patients. In 3 cases, duct dilatation was not possible due to scarring. Symptomatic relief was achieved in 81/91 patients (89.4%). Strictures and mucous plugs were visualized and managed in 18/18 patients. Sialoliths were visualized in 73 patients and stone fragmentation or retrieval was accomplished in 84.93% (62/73) of cases. Complications included 2 patients with temporary lingual nerve paresthesia and 1 patient with excess extravasation of irrigation fluid. CONCLUSION: The results of this study indicate that interventional sialoendoscopy is an effective, minimally invasive alternative treatment for obstructive salivary gland disease.

• Development of a biodegradable scaffold with interconnected pores by heat fusion and its application to bone tissue engineering.

  Authors: Michael Shin, Harutsugi Abukawa, Maria J Troulis, Joseph P Vacanti

  Journal of biomedical materials research. Part A. 04/2008; 84(3):702-9.

  Tissue engineering has been proposed as an approach to alleviate the shortage of donor tissue and organs by combining cells and a biodegradable scaffold as a temporary extracellular matrix. WhileTissue engineering has been proposed as an approach to alleviate the shortage of donor tissue and organs by combining cells and a biodegradable scaffold as a temporary extracellular matrix. While numerous scaffold fabrication methods have been proposed, tissue formation is typically limited to the surface of the scaffolds in bone tissue engineering applications due to early calcification on the surface. To improve tissue formation, a novel scaffold with a hierarchical interconnected pore structure on two distinct length scales has been developed. Here we present the fabrication process and the application of the scaffold to bone tissue engineering. Porous poly(lactide-co-glycolide) (PLGA) scaffolds were made by combining solvent casting/particulate leaching with heat fusion. Porcine bone marrow-derived mesenchymal stem cells (MSCs) were differentiated into osteoblasts and cultured on these scaffolds in vitro for 2, 4, and 6 weeks. Subsequently, the constructs were assessed using histology and scanning electron microscopy. The bone marrow-derived osteoblasts attached well on these scaffolds. Cells were observed throughout the scaffolds. These initial results show promise for this scaffold to aid in the regeneration of bone.

• Condylectomy and costochondral graft reconstruction for treatment of active idiopathic condylar resorption.

  Authors: Maria J Troulis, Fardad T Tayebaty, Maria Papadaki, W Bradford Williams, Leonard B Kaban

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 02/2008; 66(1):65-72.

  PURPOSE: The purpose of this study was to evaluate the outcomes in patients with active bilateral idiopathic condylar resorption treated by condylectomy and costochondral graft (CCG) reconstruction.PURPOSE: The purpose of this study was to evaluate the outcomes in patients with active bilateral idiopathic condylar resorption treated by condylectomy and costochondral graft (CCG) reconstruction. PATIENTS AND METHODS: This was a retrospective evaluation of 15 consecutive patients treated at Massachusetts General Hospital from 1999 to 2004 who had: 1) active bilateral idiopathic condylar resorption confirmed by clinical examination, plain radiographs, and technetium-99 bone scan; 2) adequate documentation; and 3) a minimum of 12 months follow-up. Patients with an identifiable cause of condylar resorption such as rheumatoid or degenerative arthritis, trauma, or steroid use, or who had less than 12 months follow-up were excluded. Preoperative, immediate postoperative, 6-month, 12-month, and latest follow-up clinical examinations, lateral cephalograms, and panoramic radiographs were used to evaluate the outcomes. Inferior alveolar and marginal mandibular nerve function, jaw motion, and occlusion were evaluated by history and physical examination. All patients underwent bilateral condylectomy and CCG reconstruction. RESULTS: There were 13 female and 2 male patients with a mean age of 24 years. Mean follow-up was 34 months (range, 12 to 84). Preoperatively, all patients had Class II malocclusion: mean overjet 6.2 mm and mean anterior open bite -2.65 mm. At latest postoperative follow-up, all patients showed Class I occlusion with no anterior open bite, a stable and reproducible occlusion, and a normal range of TMJ motion with a mean maximal incisal opening of 39 mm. CONCLUSION: The results of this study indicate that a stable and satisfactory outcome is achievable in patients with active idiopathic condylar resorption treated by condylectomy and CCG reconstruction.

• Adjuvant antiangiogenic therapy for giant cell tumors of the jaws.

  Authors: Leonard B Kaban, Maria J Troulis, Michael S Wilkinson, Michael J Wilkinson, David Ebb, Thomas B Dodson

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 11/2007; 65(10):2018-24; discussion 2024.

  PURPOSE: To further evaluate a novel treatment protocol for the management of aggressive giant cell lesions (GCLs) consisting of enucleation followed by adjuvant subcutaneous interferon alphaPURPOSE: To further evaluate a novel treatment protocol for the management of aggressive giant cell lesions (GCLs) consisting of enucleation followed by adjuvant subcutaneous interferon alpha therapy. PATIENTS AND METHODS: Using a retrospective case series study design, a sample of patients with aggressive GCLs was enrolled between April 1995 and June 2006. Lesions were enucleated with preservation of vital structures. Postoperatively, the patients received daily subcutaneous interferon alpha (3 million units/m2 of body surface area). Interferon treatment continued with regular clinical and radiographic follow-up until the surgical defects filled in with bone, as demonstrated by panoramic radiographs and confirmed by computed tomography. Side effects, such as fever, fatigue, weight loss, decreased white blood cell count, decreased platelet count and elevated liver enzymes, were monitored. After completion of interferon therapy, patients followed for 2 years without evidence of recurrence were considered cured of disease. RESULTS: The study sample was comprised of 26 subjects (65% female) with a mean age of 18.5 years. At the time of this writing, 16 of the subjects have completed the protocol and are cured of disease, 6 are in remission, and 4 are in active treatment. Four subjects experienced significant side effects from the interferon, requiring modification of treatment. CONCLUSIONS: Enucleation of aggressive GCLs with preservation of vital structures and adjuvant interferon is an excellent strategy for managing aggressive GCLs. Approximately 15% of subjects developed significant side effects limiting interferon administration and necessitating alternative therapies.

• Isolated microtia as a marker for unsuspected hemifacial microsomia.

  Authors: Ivan J Keogh, Maria J Troulis, Angelo A Monroy, Roland D Eavey, L B Kaban

  Archives of otolaryngology--head & neck surgery. 11/2007; 133(10):997-1001.

  OBJECTIVE: To determine the proportion of hemifacial microsomia (HFM) in patients with unilateral or bilateral "isolated" microtia. DESIGN: Prospective cohort clinical study. SETTING:OBJECTIVE: To determine the proportion of hemifacial microsomia (HFM) in patients with unilateral or bilateral "isolated" microtia. DESIGN: Prospective cohort clinical study. SETTING: University-affiliated, tertiary referral clinic for patients with microtia. PATIENTS: One hundred consecutive patients with isolated microtia. INTERVENTIONS: All the patients underwent a clinical examination and audiologic evaluation. The OMENS classification system was used to grade the severity of craniofacial features: orbital deformity, mandibular hypoplasia, ear deformity, nerve (cranial nerve VII) involvement, and soft-tissue deficiency. Each anatomical abnormality was graded from 0 (normal) to 3 (most severe) (score range, 0-15). MAIN OUTCOME MEASURES: The OMENS scores, percentage of patients with isolated microtia and undiagnosed HFM, and isolated microtia as an early clinical marker for HFM. RESULTS: Forty patients (40%) with microtia were determined to have HFM (31 unilateral and 9 bilateral). Mean patient age was 9.2 years (range, 6 weeks to 41 years), with male predominance (27 males and 13 females). The OMENS scores were less than 5 in 24 patients and 6 to 10 in 16 patients. Thirty patients had cranial nerve deficits, and 37 had mandibular asymmetry. Thirty-seven patients demonstrated conductive hearing loss, and 1 had sensorineural hearing loss. CONCLUSIONS: Isolated microtia served as an early clinical marker for asymmetrical facial growth in 40% of the patients. Isolated microtia and HFM could represent a spectrum of expression of the same developmental phenomenon.