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ABSTRACT: Surface modification of titanium alloy implants to enhance soft tissue adherence is important to minimize soft tissue dehiscence. This study aimed to confirm if a dual acid etched "Osseotite®" titanium surface contributes to soft tissue adherence in muscle. It also aims to explore if a radio frequency magnetron sputtered hydroxyapatite (HA)/bioglass (BG) coating can serve this purpose and provides soft tissue adherence in mucosal tissue. The study was carried out in 18 Macaca fascicularis animals, 14 Osseotite® coated Ti6Al4V bullets inserted intramuscularly and 12 HA/BG coated Ti6Al4V plates inserted into the submucosa. These were compared with machined Ti6Al4V surfaces as controls. The histological and histomorphometrical results revealed that no significant difference existed in muscle tissue response between machined and Osseotite® surfaces. On the other hand, the HA/BG coated submucosal plates showed statistically significant differences with a thinner capsule quantity (p < 0.0001), an increased capsule quality (p < 0.0001) and interface quality score (p < 0.05). In conclusion, the deposited HA/BG coatings facilitated soft tissue (mucosa) adaptation at 1 month of implant installation, whereas the acid etched Osseotite® surface did not enhance muscular adaptation.
Journal of Biomedical Materials Research Part A 11/2010; 95(2):543-9. · 2.63 Impact Factor
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ABSTRACT: To assess, using cone-beam computed tomography and histologic examination, whether the fixation of a condyle-ascending ramus mandibular modular endoprosthesis results in a physiologic condylar replacement in Macaca fascicularis.
The right condyle and ascending ramus were resected in 8 adult monkeys and replaced with a modular endoprosthesis, fixed with polymethyl methacrylate bone cement (Palacos). Four monkeys were sacrificed at 3 months and another 4 at 6 months postoperatively. The reconstructed and contralateral temporomandibular joints were harvested en bloc and studied using cone-beam computed tomography and descriptive histologic examination. Heterotopic bone formation was quantified using a modified grading scale. The condyle cartilage thickness in the contralateral temporomandibular joint was measured using histomorphometric methods. The results were compared with those of the unoperated control monkeys.
Bone resorption in the glenoid fossa and pathologic changes in the articular disc were noted on the reconstructed side in most specimens. Nevertheless, cone-beam computed tomography findings, histologic findings, and condyle cartilage thickness measurements of the contralateral temporomandibular joint were not significantly different from those of the control specimens.
Replacement of the condyle and ascending ramus using a modular endoprosthesis in Macaca fascicularis resulted in adaptive remodeling of the glenoid fossa at up to 6 months postoperatively. Long-term studies are required to further assess the potential of this mode of reconstruction.
Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons 09/2010; 68(9):2136-45. · 1.58 Impact Factor
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ABSTRACT: To assess whether the fixation of a condyle-ascending ramus mandibular modular endoprosthesis, using bone cement, will result in stress-related bone resorption in the Macaca fascicularis.
The right condyle and ascending ramus were resected in 8 adult monkeys and replaced by a modular endoprosthesis, fixed with polymethylmethacrylate bone cement (Palacos). Four monkeys were sacrificed at 3 months and another 4 at 6 months postoperatively. The bone mineral density was assessed using dual-energy x-ray absorptiometry in the region anterior to the stem and using micro-computed tomography in the buccal, lingual, and inferior regions adjacent to the stem.
The bone mineral density of the 3-month specimens was greater than that at 6 months in the buccal, lingual, and inferior regions adjacent to the stem. However, the difference was statistically significant only in the inferior aspect. No significant difference was found in the bone mineral density in the region anterior to the stem between the 3- and 6-month specimens.
A minimal reduction in bone density around the stem of the endoprosthesis was observed between 3 and 6 months after placement. This reduction did not result in any adverse clinical events.
Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons 08/2010; 68(8):1776-82. · 1.58 Impact Factor
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ABSTRACT: To determine changes in quality of life (QoL) after orthodontic-surgical treatment in patients with dentofacial deformities, using generic health, generic oral health, and condition-specific QoL approaches.
Patients were evaluated at baseline (T(0)), postoperative 6 weeks (T(1)), postoperative 6 months (T(2)), and after orthodontic treatment (T(3)). Generic health-related QoL, generic oral health-related QoL, and condition-specific QoL were assessed using the 36-item Short Form Health Survey (SF-36), the 14-item Short Form Oral Health Impact Profile (OHIP-14), and the 22-item Orthognathic Quality of Life Questionnaire (OQLQ), respectively.
There were significant changes in Physical-Health Component Scores (PCS) (P < .001) and Mental-Health Component Scores (MCS) (P < .01) of SF-36, in OHIP-14 scores (P < .001), and in OQLQ scores (P < .001) during the trajectory of treatment. A transient decrease in PCS was found at T(1) (P < .001) and an increase in MCS was found only at T(3) (P < .05). There was a significant decrease in OHIP-14 scores at T(2) and T(3) (P < .001) and in OQLQ scores at all time points compared with T(0) (P < .05).
Significant changes in QoL occurred after orthodontic-surgical treatment. A comprehensive assessment of QoL using generic health, generic oral health, and condition-specific approaches proved to be useful in determining the trajectory of changes.
Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics 01/2010; 109(1):46-51. · 1.50 Impact Factor
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ABSTRACT: The present study presents the microcomputed tomographic and histologic evaluation of the peri-implant tissues of a modular endoprosthesis used to replace the condyle and ascending ramus in Macaca fascicularis.
The right condyle and ascending ramus were resected in 8 adult monkeys and replaced by a modular endoprosthesis, fixed with polymethylmethacrylate bone cement (Palacos). Four monkeys were sacrificed at 3 months and 4 at 6 months postoperatively. Microcomputed tomographic scanning was performed to analyze the bone volume at the bone-cement interface. Histologic and histomorphometric assessments were done using a modified hard and soft tissue grading scale and by studying the total bone contact at the interface.
The combined (buccal, lingual, and inferior) mean bone volume percentage of the 6-month group was significantly greater than that of the 3-month group (P < .05). The 6-month specimens showed a reduced inflammatory response and more abundant bone formation around the stem. The total soft tissue histologic score was significantly greater in the 6-month group (P < .05). A total bone contact percentage of 15.4% to 85.2% was achieved in 3 specimens.
Satisfactory bone growth was found at the bone-cement interface at the stem region, although direct bone contact with the cement was not achieved in all cases. Soft tissue contact with the prosthetic ramus, in the form of a fibrous capsule, was present in some areas. At 6 months, minimal interfacial inflammation was found in this monkey model.
Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons 12/2009; 67(12):2617-26. · 1.58 Impact Factor
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ABSTRACT: To evaluate the feasibility of replacing the condyle and ascending ramus with a novel modular endoprosthesis in Macaca fascicularis.
Eight male adult monkeys (Macaca fascicularis) were used in this study. The right condyle and ascending ramus posterior to the lower second molar were resected. An endoprosthesis consisting of 2 modules was inserted to replace the resected segment and fixed in place using polymethylmethacrylate bone cement (Palacos). Four monkeys were sacrificed at 3 months and another 4 at 6 months postoperatively. The operated side of the mandible was then harvested, including the endoprosthesis and the stump of the mandible to which it was attached. Lateral mandibular radiographs were taken using standard settings immediately postoperatively and postsacrifice.
Two monkeys presented with a fistula at the operated area 1 month postoperatively, but this resolved with a short course of antimicrobial treatment. At the time of sacrifice, no fistulas, dehiscences, or mobility of the endoprostheses was observed. There was no significant change in maximum mouth opening. At 3 months, a linear radiolucency was noted at the cement-bone interface in the 2 monkeys that previously presented with fistulas; whereas at 6 months, none of the 4 animals showed any radiolucency.
The use of a cemented modular endoprosthesis for replacement of the condyle and ramus unit was feasible with minimal complications allowing normal mouth opening and occlusion. Further histologic and microfocus computed tomographic studies will be done to confirm the findings.
Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons 08/2009; 67(7):1392-400. · 1.58 Impact Factor
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ABSTRACT: Mandibular defects may result from trauma, inflammatory disease and benign or malignant tumours. Mastication, speech and facial aesthetics are often severely compromised without reconstruction. The goal of mandibular reconstruction is to restore facial form and function, implying repair of mandibular continuity and muscle attachments. There should also be room for implant insertion so as to allow for rehabilitation of occlusion and articulation, whereas the function of the inferior alveolar nerve should be restored to assure adequate sensitivity of the lips. Mandibular reconstruction principles and techniques have evolved dramatically over the years. Refinements in techniques continue to improve patient quality of life. This paper reviews current techniques of mandibular reconstruction in adults and discusses the strengths and weaknesses of each.
International Journal of Oral and Maxillofacial Surgery 08/2008; 37(7):597-605. · 1.51 Impact Factor
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ABSTRACT: To determine changes in quality of life (QOL) following orthognathic surgery in patients with dentofacial deformity, using generic health, generic oral health, and condition-specific QOL approaches.
Thirty-six patients were evaluated at baseline presurgical (T(0)), 6 weeks postoperatively (T(1)), and 6 months postoperatively (T(2)). Generic health-related QOL was assessed using the 36-item Short Form Health Survey (SF-36), generic oral health-related QOL was assessed by the 14-item Short Form Oral Health Impact Profile (OHIP-14), and condition-specific QOL was assessed by the 22-item Orthognathic Quality of Life Questionnaire (OQLQ).
There was a significant reduction (deterioration) in SF-36 summary physical (P < .01) and mental health scores (P < .001) at 6 weeks after surgery but no significant change in overall OHIP-14 or OQLQ scores. At 6 months after surgery, SF-36 summary scores returned to baseline levels and significant reduction (improvements) in OHIP-14 (P < .001) and OQLQ mean scores (P < .001) were observed.
Significant changes in QOL occurred following orthognathic surgery. A marked but transient deterioration in many aspects related to general well being was noted in the early postoperative period and significant improvement was documented by 6 months. A comprehensive assessment of QOL using generic health, generic oral health, and condition-specific approaches proved useful in determining such changes.
Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons 07/2008; 66(6):1194-9. · 1.58 Impact Factor
