• The Journal of Korean Academy of Prosthodontics
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• v.55 no.2
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• pp.198-204
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• 2017

Maxillofacial defect comes from congenital defect, trauma and surgical resection. Patients with intraoral defect are commonly related to maxillary defect and they need prosthetic rehabilitation. Functional reconstruction of partially edentulous mandible has many limitations. However, if both condyles are intact, maxillofacial prosthesis using partial denture give competent results. In this case, a patient of 58 year-old male has a defect on palate and left mandibular posterior teeth from gunshot. The maxillary defect of this patient is Class IV according to Aramany classification and the mandibular one is Type V according to Cantor and Curtis classification. For retention of the obturator, remaining teeth are fully utilized and artificial teeth are arranged harmoniously to provide stable occlusion. Mandibular RPD covered limited range of deformed soft tissue derived from mandibular resection surgery. With these treatments, the patient in this case showed improvements in mastication, swallowing and speech.

• Imaging Science in Dentistry
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• v.46 no.1
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• pp.39-45
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• 2016

The incidental finding of an enlarged mastoid foramen on the right posterior mastoid region of temporal bone is reported, together with a discussion of its clinical significance. A 67-year-old female underwent the pre-implant assessment of a maxillary left edentulous region. A cone-beam computed tomographic (CBCT) image was acquired and referred for consultation. Axial CBCT slices revealed a unilateral, well-defined, noncorticated, low-attenuation, transosseous defect posterior to the mastoid air cells in the right temporal bone. The borders of the osseous defect were smooth and continuous. No other radiographic signs suggestive of erosion or sclerosis were noted in the vicinity. The density within the defect was homogenous and consistent with a foramen and/or soft tissue. The patient's history and physical examination revealed no significant medical issues, and she was referred to a neuroradiologist for a second opinion. The diagnosis of an enlarged mastoid foramen was made and the patient was reassured.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.2
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• pp.137-144
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• 1994

Inselecting scars for treatment, attention be paid not only to the features of the defect as seen objectively but also to the element of the defect most disturbing to the patient. We revised the scar tissues with simple elliptical excision, Z-plasty, modified Z-plasty, W-plasty and hand dermabrasion in varialbe pattern of scars and got the favorable results. The success rate of scar revision usually depends on the patient's subjective judgement. We must inform our patient the limitation of scar revision and importance of postoperative care. The oral and maxillofacial surgeons must resolve the variable scars which re involved in variable operations and traumas.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.4
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• pp.316-322
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• 2004

A low molecular weight component named bone morphogenetic protein(BMP) chemically isolated from the organic matrix of bone, induce postfetal connective tissue cells surrounding small blood vessels to differentiate into cartilage and bone. The end product of BMP is a spherical ossicle of lamella bone filled with red bone marrow for the functional loading. This is a important point that the graft material is embedded the defect site during the implant surgery. Because present knowledge of the relationship between BMP and bone regeneration arises mainly from studies of induced bone formation in heterotopic sites, it would be helpful to determine whether BMP plays any part in the process of bone healing. The BMPs have been shown to play crucial roles in normal skeletal development as well as bone healing and are able to activate transcription of genes involved in cellular migration, proliferation, and differentiation. The delivery of BMP on matrices has been efficacious in the treatment of defect bone in implant surgery. The purpose of the histologic study was to evaluate the effect of DLB(demineralized lyophilized bone) coated with purified human BMP(hBMP-I) in immediate implant surgery with bony defect to obtain the functional structure of implant asap. The ability of a graft of hBMP-I to accelerate bony defect repair provides a rationale for its use in immediate implant surgery that have large bone defect in edentulous area.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.1
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• pp.13-17
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• 2013

Purpose: This study evaluated the capability of bone formation of silk fibroin particles coated with hydroxyapatites (HA/SF), as bone graft material when put into the calvarial defect of rats. Methods: Twenty Sprague Dawley rats were used for this study and round shaped defects were formed in the center of parietal bones (diameter: 8.0 mm). The defect was filled with (1) HA/SF (experimental group), or (2) left as a vacant space (control group). The animals were sacrificed at 4 or 8 weeks, postoperatively. The specimens were decalcified and stained with Masson's trichrome for histomorphometric analysis. Results: The average of new bone formation was $33.18{\pm}3.10%$ in the experimental group and $20.49{\pm}5.79%$ in the control group at 4 weeks postoperatively. That was $42.52{\pm}7.74%$ in the experimental group and $25.50{\pm}7.31%$ in the control group at 8 weeks postoperatively. The difference between the groups was significantly higher at both 4 weeks and 8 weeks postoperatively (P<0.05). Conclusion: The rat calvarial defect was successfully repaired by HA/SF graft. The HA/SF graft showed more new bone formation compared with the unfilled control.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.4
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• pp.274-279
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• 2002

The purpose of this study is to evaluate the critical maintenance period of absorbable membrane for guided bone regeneration. Fortynine Sprague-Dawley rats weighing about 300g were divided into seven groups. An 8 mm circular full-thickness defect in calvarial bone was made and then cellular acetate porous filter (Millipore $filter^{(R)}$.) was placed on the calvarial bone defect. The filter was removed at 2, 3, 4, 5, 6, 8 and 11 weeks after placement. Rats were sacrificed at 12 weeks the placement of cellular acetate porous filter. The specimens were stained with Hematoxylin-Eosin and observed under light microscope. The amount of regenerated bone was measured from both margin of calvarial bone defect (unit : mm). The results were as follows. Bone regeneration of each experimental group was increased gradually and the bond defect was almost completely filled with new bone in 5-, 6-, 8-, and 11-week experimental group. Histologic findings showed mild inflammatory response and granulation tissue formation without apparent adverse effects on the healing process. In 11-week experimental group, the bone defect was completely filled with new bone containing abundant osteoid which was oriented to the dural side and contribute to bony thickening. We suggest that non-absorbable membrane and bioabsorbable membrane presumably should remain intact for longer than 5 weeks to be effective.

• Imaging Science in Dentistry
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• v.37 no.2
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• pp.69-77
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• 2007

Purpose: To evaluate the accuracy of the imaging reformation of cone beam computed tomography for the assessment of bone defect healing in rat model. Materials and Methods: Sprague-Dawley strain rats weighing about 350 gms were selected. Then critical size bone defects were done at parietal bone with implantation of collagen sponge. The rats were divided into seven groups of 3 days, 1 week, 2 weeks, 3 weeks, 4 weeks, 6 weeks, and 8 weeks. The healing of surgical defect was assessed by multi planar reconstruction (MPR) images and three-dimensional (3-D) images of cone beam computed tomography, compared with soft X-ray radiograph and histopathologic examination. Results: MPR images and 3-D images showed similar reformation of the healing amount at 3 days, 1 week, 2 weeks, and 8 weeks, however, lower reformation at 3 weeks, 4 weeks, and 6 weeks. According to imaging-based methodologies, MPR image revealed similar reformation of the healing amount than 3-D images compare with soft X-ray image. Among the four threshold values for 3-D images, 400-500 HU revealed similar reformation of the healing amount. Histopathologic examination confirmed the newly formed trabeculation correspond with imaging-based methologies. Conclusion: MPR images revealed higher accuracy of the imaging reformation of cone beam computed tomography and cone beam computed tomography is a clinically useful diagnostic tool for the assessment of bone defect healing.

• Imaging Science in Dentistry
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• v.42 no.4
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• pp.261-263
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• 2012

Developmental salivary gland defect is a bone depression on the lingual surface of the mandible containing salivary gland or fatty soft tissue. The most common location is within the submandibular gland fossa and often close to the inferior border of the mandible. This defect is asymptomatic and generally discovered only incidentally during radiographic examination of the area. This defect also appears as a well-defined, corticated, unilocular radiolucency below the mandibular canal. Although it is not uncommon for this defect to appear as a round or ovoid radiolucency, multilocular radiolucency of these defects is relatively rare. This report presents a case of a developmental salivary gland defect with multilocular radiolucency in a male patient.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.34.1-34.7
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• 2020

Purpose: The purpose of this study was to evaluate the influence of biodegradable polycaprolactone membrane on new bone formation and the biodegradation of biphasic alloplastic bone substitutes using animal models. Materials and methods: In this study, bony defect was formed at the canine mandible of 8 mm in diameter, and the defects were filled with Osteon II. The experimental groups were covered with Osteoguide as barrier membrane, and the control groups were closed without membrane coverage. The proportion of new bone and residual bone graft material was measured histologically and histomorphometrically at postoperative 4 and 8 weeks. Results: At 4 weeks, the new bone proportion was similar between the groups. The proportion of remaining graft volume was 27.58 ± 6.26 and 20.01 ± 4.68% on control and experimental groups, respectively (P < 0.05). There was no significant difference between the two groups in new bone formation and the amount of residual bone graft material at 8 weeks. Conclusion: The biopolymer membrane contributes to early biodegradation of biphasic bone substitutes in the jaw defect but it does not affect the bone formation capacity of the bone graft.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.5
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• pp.292-296
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• 2023

Generally, if the size of a lip cancer defect exceeds 30% of the lower lip, a local flap or free flap is recommended. However, defects up to 50% of the lower lip in size have been reconstructed successfully by primary closure without a local flap or free flap. In one case, an 80-year-old male farmer who had smoked for more than 50 years presented with squamous cell carcinoma of the lower lip and underwent mass resection and supraomohyoid neck dissection. The defect accounted for almost 2/3 of the lower lip and was repaired by primary closure with V-shaped resection. Biopsy results confirmed pT2N0cM0 stage II disease with clear margins. In another case, a 68-year-old male also presented with squamous cell carcinoma of the lower lip and underwent mass resection. The defect accounted for about half the size of the lower lip but was repaired by primary closure with V-shaped resection. Both patients experienced no discomfort while eating or speaking and were satisfied with the cosmetic and functional outcomes with no evidence of recurrence. Thus, direct closure can be considered even in large lower lip cancers.