橋體徑距長度對纖維強化壓克力暫用固定局部義齒之影響：臨床研究

Effect of pontic span length on the fiber-reinforced acrylic provisional FPDs:a clinical study

葉盈慧(Ying-Huei Yeh)

指導教授 ： 王震乾

高雄醫學大學/口腔醫學院/牙醫學研究所/碩士(2013年)

https://doi.org/10.6832/KMU.2013.00081

摘要

研究目的： 本研究之目的為評估不同徑距長度之玻璃纖維強化壓克力暫用固定局部義齒在臨床上抵抗破折斷裂之表現。 研究方法：本研究的設計為前瞻性單盲試驗。篩選後牙區缺牙兩顆以上，需要製作長徑距暫用固定局部義齒的自願者，經詳細說明後符合納入條件者進行資料收集，印模後由模型先在實驗室製作暫用固定局部義齒。使用的材料為PMMA 自聚合型樹脂，並以隨機分配的方式分為實驗組(一束玻璃纖維強化張力側)和對照組(未強化)。病人裝置暫用固定局部義齒後每個月回診追蹤至少三個月以觀察補綴物是否產生斷裂或破損，並以統計軟體進行Kaplan-Meier 存活分析、Cox比例風險迴歸分析及以ROC curve尋找關鍵徑距長度。 結果：從2011年九月至2012年十二月共招募33位成年病人，13位男性、20位女性。共製作45個暫用固定局部義齒，其中有一位病人中途退出，drop out rate為3%(1/33)。實驗組以纖維強化（n=21）,對照組則無纖維強化（n=23）。實驗組和對照組再依橋體徑距長度分為三組進行存活分析:橋體徑距長度小於17mm、17∼20mm及大於20mm。其180天存活率分別為實驗組：100.0%、100.0%、42.9%；對照組81.8%、62.5%、25.0%。橋體徑距長度大於20mm其斷裂的風險為小於17mm之10.52倍（P值<0.05）。橋體徑距長度越長越容易產生斷裂，徑距長度顯著影響存活率。未強化的樣本在徑距長度16.9mm以上就容易產生斷裂，而以纖維強化的樣本在21.4mm以上才容易產生斷裂。 結論：壓克力暫用固定局部義齒的橋體徑距長度越長，臨床上發生斷裂的機率越高。橋體徑距長度在17~21mm之間以玻璃纖維強化可以有效提高存活率及減少斷裂。而21mm以上的徑距長度以纖維強化無法有效防止斷裂，須尋求其他強化方式。

關鍵字

暫用固定局部義齒 ； 壓克力樹脂 ； 玻璃纖維 ； 纖維強化 ； 橋體徑距長度

並列摘要

Purpose：The purpose of this study was to evaluate the clinical performance of long span fiber-reinforced acrylic provisional fixed partial dentures (FPDs) with various pontic span lengths.
Materials and Methods：This prospective single-blind study included volunteers who needed fabricated long span provisional fixed partial dentures to replace more than two posterior teeth. The auto-polymerized PMMA resin was used for fabrication of the provisional FPDs from the study casts of selected adult patients. The provisional FPDs were randomly divided into test and control groups. The test group samples consisted of one bundle glass fiber reinforced in the tension side according to their different pontic span length, and the control group was unreinforced. The clinical performance of the provisional FPDs was recorded every month after delivery to detect any occurance of fractures or cracks. The data were analyzed using Kaplan-Meier survival analysis to compare the survival curves, and the Cox proportional hazards model to calculate odds ratio. Finally, ROC curve was conducted to find the ideal pontic span length for glass fiber reinforcement.
Results：A total of 45 provisional FPDs were made for 33 patients (male 13, female 20) from September 2011 to December 2012. Follow-up for one patient was lost, therefore the drop out rate is 3% (1/33). The test group consisted of 21 fiber-reinforced provisional FPDs, while the unreinforced control group had 23 FPDs. The test
and control groups were divided further into <17mm, 17- 20mm and >20mm subgroups according to various pontic span lengths. The 180 days survival rate of these three test subgroups were 100%、100%、42.9%, and control subgroups were 81.8%、62.5%、25.0%, respectively. The odds ratio of fracture for pontic span length >20mm subgroup was 10.52 times higher (p<0.05) than that of <17mm subgroup. The results indicate a strong association between the pontic span length and clinical fracture rate. The unreinforced provisional FPDs can easily fracture with a pontic span length longer than 16.9mm. For reinforced provisional FPDs, fractures may occurs when pontic span length is greater than 21.4mm.
Conclusions：The clinical fracture rate of provisional FPDs is correlated with pontic span length. When pontic span length is between 17 and 21mm, glass fiber reinforced PMMA resin can effectively prevent fracture. Fiber reinforcement method is not effectual for acrylic provisional FPDs with pontic span length greater than 21mm.
Keywords：Provisional fixed partial denture, acrylic resin, glass fiber,
fiber-reinforced, pontic span length

並列關鍵字

provisional fixed partial denture,acrylic resin,glass fiber,fiber-reinforced,pontic span length

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