從骨密度、植體設計和手術技巧來探討牙科植體放置過程中產生的熱影響

Heat generation during implant placement: effect of bone density,implant design and surgical technique

陳昱廷(Yu-Ting Chen)

指導教授 ： 林立德

國立臺灣大學/牙醫專業學院/臨床牙醫學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.01177

摘要

實驗目的
要達到成功的骨整合，首先在手術中要避免產生熱傷害，造成骨壞死。在之前的研究中，鑽針鑽孔對於周圍骨頭溫度的變化已經有廣泛的研究，而另一個造成溫度變化的來源是植體轉入的摩擦熱，植體轉入的摩擦熱受到骨質、植體設計、手術方法等等因素影響，而迷你植體中廠商有建議的植體轉入速度來避免過熱。因此本篇文章嘗試去探討在不同的骨質、植體設計和植體植入轉速對於植體置入時周圍骨塊不同深度溫度變化的影響。
實驗材料與方法
以SawboneR test block做為實驗材料，並選擇不同的密度（10、20pcf分別代表0.16、0.32g/cc）來模擬不同骨密度的海綿骨，並以50pcf(0.80 g/cc)之0~1mm的薄層覆蓋在test block上以模擬不同厚度之皮質骨。測試用植體則是選用NobelActive™ implant (Nobel Biocare, Sweden)，長度為10mm，直徑為4.3mm，和Branemark System™ MKIV TiUnite implant (Nobel Biocare, Sweden)，長度為10mm，直徑為4mm。
將testing block（15*30mm in diameter）固定在夾具上後，參照植體廠商所建議的鑽孔規則，在laminated block如1+10pcf骨塊中，NobelActive植體預備分別用直徑2mm的twist drill、2.4/2.8mm twist drill、3.2mm twist drill鑽入10mm的深度，MKIV植體預備分別用直徑2mm的twist drill、2.4/2.8mm twist drill、3mm twist drill加上countersink。
在沒有laminated block如10pcf和20pcf骨塊中，NobelActive植體預備分別用直徑2mm的twist drill、2.4/2.8mm twist drill鑽入10mm的深度，MKIV植體預備分別用直徑2mm的twist drill、2.4/2.8mm twist drill鑽入10mm的深度。
距離植體邊緣0.5mm處用1.5mm鑽針鑽與植體位置平行的1mm、5mm、9mm深度，作為放置熱電偶的孔洞，用水浴機(Almore International Inc., USA)模擬顎骨體溫，溫度設定範圍29℃±2℃，每一組合情況皆測試六次，而植體植入過程中，溫度數據擷取頻率為5Hz，將得到溫度最溫度變化曲線圖和植體植入時間，並算出溫度最高點和最低點的差距
實驗結果
在MKIV植體中，不管在哪種測試骨塊和置入轉速，溫度變化最高量在5mm，從植體置入轉速來看，隨著轉速增加，溫度變化量無顯著差異。而從骨塊的影響來看，10pcf、20pcf、1+10pcf，兩兩之間都不管在哪個深度溫度變化都有顯著性著差異，所以在1+10pcf在1mm、5mm、9mm比起其他骨塊都會最高溫度變化量。
在NA植體中，不管在哪種測試骨塊和置入轉速，溫度變化最高量大多出現在5mm。而植體置入轉速對於溫度變化量無顯著影響。從骨塊的影響來看，10pcf和20pcf相比，不管在哪個深度，在20pcf溫度變化量都有顯著性的增加，而在將1+10pcf with wrench組和20pcf相比，在1mm深度溫度變化量顯著增加。
在MKIV和NA植體比較中，拿出20pcf骨塊的情況相比，因在20pcf骨塊中兩者的最終鑽針是相同的，兩者之間不管在1mm、5mm、9mm，在MKIV都有顯著性較多的變化量，其可能的原因是NA在螺紋深度較深、切削能力較強，較容易通過緻密骨塊，較少的能量轉變成熱。
結論
在本實驗測試不同植體、骨塊、植體置入轉速對植體置入摩擦熱的影響，發現隨著骨質密度增加，溫度變化量增加，而隨者置入轉速的增加，溫度變化量不受影響，而植體設計對於溫度變化量會有影響，而怎麼樣的設計會如何影響，需要更進一步的研究來釐清。

關鍵字

植體置入 ； 摩擦熱 ； 熱電偶 ； 骨密度 ； 植體設計 ； 植體置入轉速

並列摘要

Research goal
The purpose of this study was to investigate the effects of bone density, implant design, and implant insertion speed on the heat generated during implant insertion.
Material and method
Three thermal couples (Advance Instrument Inc., Taiwan) was placed in 1mm,5mm,9mm depth respectively, and the temperature change was measured during implant placement.
＜Artificial test block＞
Low to high density cancellous bone without cortical coverage were simulated with 10 pounds per cubic foot (pcf) (density: 0.16 g/cc), 20 pcf (0.32 g/cc) polyurethane foam test blocks. Cancellous bone with a thin layer of cortical bone were simulated with laminated test blocks using a combination of 0 or 1 mm 50 pcf (density: 0.80 g/cc) polyurethane layer. Inserting two different implants were NobelActive™ implant (Nobel Biocare, Sweden) with 10mm in length and 4.3mm in diameter and Branemark System™ MKIV TiUnite implant (Nobel Biocare,Sweden) with 10mm in length and 4mm in diameter。
Three paralleled channels for thermal couples were drilled around the implant site. The channels were 0.5mm away from the planned implant site. The bone block was socked in a water bath (Almore International Inc., USA) which was maintained in 29±2℃.Then, implant was placed by motor (NSK, Japan) and the temperature change was recorded during the implant placement by16 channel thermal meter (VTI Instruments Corp, U.S.A).
Result:
In MKIV groups, there were no statistically difference on temperature change when different insertion speeds were used. However, with increasing bone block density, the temperature change were increased. The maximum temperature was increased in 1+10pcf bone block, it show that the laminated layer has significantly influence on the friction heat. Moreover, No matter what the bone density and insertion speed were used, the temperature change in 5mm depth were more than in 1mm depth and 9mm depth.
In NA groups, It was also that no statistically difference between the different insertion speed. With the different bone density on 10pcf and 20pcf , It is statistically difference on temperature change on 1mm,5mm,9mm. Moreover, when 20pcf bone block compared with 1+10pcf bone block, it is statistically increased on temperature change in 1mm depth.
When comparing NA with MKIV in 20pcf bone block, the MKIV groups had more friction heat generation on 1mm,5mm and 9mm depth , and it is statistically difference. It mean that implant design had influence on the temperature change

Conclusion:
In the present study, the factors that had influence on temperature change during implant insertion were the bone density and implant design. It is no statistically difference with different implant insertion speed.

並列關鍵字

implant insertion ； friction heat ； bone density ； implant design ； insertion speed ； thermal couple

參考文獻

Abouzgia MB, James DF (1996). Temperature rise during drilling through bone. The International Journal of Oral & Maxillofacial Implants 12(3):342-353.

Abuhussein H, Pagni G, Rebaudi A, Wang HL (2010). The effect of thread pattern upon implant osseointegration. Clinical Oral Implants Research 21(2):129-136.

Aerssens J, Boonen S, Lowet G, Dequeker J (1998). Interspecies differences in bone composition, density, and quality: potential Implications for in vivo bone research 1. Endocrinology 139(2):663-670.

Agren E, Arwili T (1968). High-speed or conventional dental equipment for the removal of bone in oral surgery: III. A histologic and microradiographic study on bone repair in the rabbit. Acta Odontologica Scandinavica 26(3):223-246.

Agren E (1963). High-speed or conventional dental engines for the removal of bone in oral surgery: I. A study of the reactions following removal of bilateral impacted lower third molars. Acta Odontologica Scandinavica 21(6):585-625.