• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권2호
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• pp.136-142
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• 2009

Bone density in the recipient implant site seems to be an important factor for long term success of endosseous implants. Preoperative evaluation of bone density is very helpful to assist the clinician with the treatment planning of implant therapy. Accurate information on bone density will help the surgeon identify suitable implant sites, thereby improving the success rate of the procedure. Purpose; The aim of this study was to evaluate a correlation between bone density measured preoperatively with computerized tomography and histologically measured bone density by bone biopsy. Patients and methods; Twenty seven patients were selected. All the patients were in good health, with no systemic disorder and additional bone graft. Preoperatively the patients underwent CT scanning to evaluate Houmsfield Unit(HU). Each patients wore a surgical template for implant placement. During surgery 2mm in diameter and 6mm in length specimens were taken. Histomorphometric analysis was performed using digitalized image analysis software Axiovision 4.3. Also, the Resonance frequency analysis(RFA) and insertion torque values were recorded. Results; The highest histomorphometric values was found in the posterior mandible $32.3{\pm}3.8$, followed by $29.9{\pm}2.6$ for the posterior maxilla, $29.4{\pm}2.6$ for the anterior maxilla, $28.6{\pm}2.3$ for the anterior mandible(p=0.214). The hounsfield unit was $989.2{\pm}258.1$ in the posterior mandible, $845.0{\pm}241.5$ in the anterior maxilla, $744.5{\pm}92.6$ in the anterior mandible, $697.3{\pm}136.9$ in the posterior maxilla(p=0.045). This results may suggest that there are strong correlation between the histomorphometric values and hounsfield unit(r=0.760, p<0.05). The RF measurements were $81.9{\pm}2.4$ ISQ in the posterior mandible, $79.0{\pm}1.4$ ISQ in the anterior mandible, $78.3{\pm}4.6$ ISQ in the posterior maxilla, $76.5{\pm}5.0$ ISQ in the anterior maxilla(p=0.048). The insertion torque values was $43.2{\pm}4.2\;Ncm$ in the posterior mandible, $42.0{\pm}0.0\;Ncm$ in the anterior mandible, $41.3{\pm}4.1\;Ncm$ in the posterior maxilla, $40.8{\pm}3.8\;Ncm$ in the anterior maxilla(p=0.612). This results may suggest that there are statistical significance between the hounsfield unit and the insertion torque values(r=0.494, p<0.05), the histomorphometric values and the insertion torque values(r=0.689, p<0.05). But there was no correlation between histomorphometric values and ISQ. There was no statistical significance in age and gender effect on parameters. Conclusions; There was significant correlations between bone density and implant stability parameters. The bone density measurements using preoperative CT may help clinicians to predict primary stability before implant insertion, which is associated with implant survival rates.

• 대한핵의학회지
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• 제28권3호
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• pp.293-300
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• 1994

두부외상후 후유증으로 기질적 정신장애를 호소하는 환자들에서 Tc-99m HMPAO 뇌혈류 SPECT 검사의 임상적 유용성을 알아보고자 교통사고 및 추락 등에 의한 두부외상후 평균 23개월이 경과되고, 지속적인 여러 정신적 장애를 호소하여 1991년 9월부터 1994년 3월까지 충남대학교병원에서 기질성 정신장애로 진단받고 Tc-99m HMPAO brain SPECT 검사를 시행한 29명의 환자들을 대상으로 본 연구를 수행하였다. 정신감정결과, CT 및 MRI 결과와 Tc-99m HMPAO brain SPECT 결과를 비교하여 다음과 같은 성적을 얻었다. 1) 두부외상후 기질적 정신장애로 진단된 환자 모두가 Tc-99m HMPAO 뇌혈류 SPECT상 이상소견을 보였으며 MRI상에서는 57%, EEG검사에서는 33%만이 이상소견을 나타냈다. 2) 대상환자 28명중 중 SPECT상 가장 많은 병변은 양측 전두엽 혈류감소 소견(68%)이었으며 MRI 검사에서도 전두엽에 병변(43%)을 보이는 경우가 가장 많았다. 3) MRI 검사상 병변부위에 SPECT상 정상 소견을 보였던 병변은 8예(22%)로 전두엽의 수활액낭종(hygroma) 4예, 작은 뇌경색부위 3예, 및 소뇌의 뇌연화증 1예 이었다. 4) MRI 검사가 정상인 환자 12명중 SPECT상 가장 많은 뇌내 병변은 양측 전두엽의 혈류감소(92%)소견이었다. 5) MMSE 검사상 20점 미만인 환자들에서 20점 이상인 환자군보다 EEG 또는 MRI상 이상소견을 보인 경우가 많았다. 이상의 결과로 저자들은 기질성 정신장애 환자에서 Tc-99m HMPAO 뇌혈류 SPECT는 MRI나 EEG보다 매우 예민한 검사방법으로 생각하였다.