4種類の二ケイ酸リチウム・セラミック・レストレーションの臨床的成功例の評価：レトロスペクティブ・スタディ

Evaluation of the clinical success of four different types of lithium disilicate ceramic restorations: a retrospective study.

抄録

背景・目的:

二ケイ酸リチウムの修復物は、破損するまでどのくらいもつのでしょうか？本研究の目的は、二ケイ酸リチウムを用いた4種類の異なる修復物の成功率を評価することである。

BACKGROUND/PURPOSE: How long do lithium disilicate restorations last before they fail? The aim of this study was to assess the success rate of four different types of restorations made from lithium disilicate.

材料と方法:

MATERIALS AND METHODS: A total of 87,203 ceramic restorations, classified into four different types (inlay or onlay, veneers (Vs), single crowns (SCs), and fixed partial dentures (FPDs)), were used. All were made of lithium disilicate (IPS e.Max CAD) with Cerec Inlab CAD/CAM system (Sirona Dental Systems, Bensheim, Germany). They were reported by dentists and entered in the database of the private B&R Dental Center between March 2015 and June 2020 and assessed retrospectively up to a period of 5 years based on the following parameters: failure rate and cause of failures (ceramic fracture, debonding, marginal adaptation, color match, endodontic intervention, periodontal disease, and secondary caries). Failure distribution according to gender, arch, and teeth type was also evaluated. The time-dependent time-to-failure/complication and their differences were calculated in months according to the Kaplan Meier and log-rank tests. The Chi-squared test (p 0.05) was used to assess the variations in causes of failure rates between different restorations.

結果:

Kaplan Meier検定によると、二ケイ酸リチウム修復物の数年間の累積生存確率は85.08%であった。インレー/オンレーおよび対セラミック修復物は、最も高い累積生存率を示した（それぞれ99.4％、98.6％）。FPDは最も低い累積生存率（52.9％）を示したが、これは他のセラミック修復物と比較して、ログランク検定で有意（P<0.00001）に高かった。さらに、Kaplan-Meier（CI：下限51.875ヵ月、上限52.871ヵ月）によると、全体の時間に依存した破損/合併症発生までの時間は52.373ヵ月であった。故障の主な原因として，FPDとSCではセラミックの破損（それぞれ27.6％と26.6％），Vsではデボンディング（12.7％）が有意に高かった（P=0.000）。失敗率は上顎弓の方が下顎弓よりも有意に高かった（P=0.021）。臼歯部では骨折が77.5％，辺縁の不一致が14.75％と，前歯部や小臼歯部に比べて有意に高かった（P=0.000）．

RESULTS: Kaplan Meier test showed overall cumulative survival probability of lithium disilicate restorations for up to years was 85.08%. Inlay/onlay and Vs ceramic restorations showed highest cumulative survival probability (99.4%, 98.6, respectively). FPDs had the least cumulative survival probability (52.9%) which was significantly (P < 0.00001) higher than for other ceramic restorations using the log-rank test. Moreover, overall time-dependent time-to-failure/complication occurred after 52.373 months according to Kaplan-Meier (CI: lower bound: 51.875 months; upper bound: 52.871 months). Ceramic fracture in both FPDs and SCs (27.6% and 26.6%, respectively) and debonding in Vs (12.7%) were significant as the main reasons for failure (P = 0.000). The failure rate was significantly higher for the maxillary arch than the mandibular arch (P = 0.021). Fracture and marginal discrepancy were more frequent in the molar region (77.5% and 14.75%, respectively) and significantly higher here than in the anterior and premolar regions (P = 0.000).

結論:

二ケイ酸リチウムの中期的な性能は理想的である。SCとFPDの破損原因はセラミックの破断が最も多かった。5年間の評価では、FPDの破損率が最も高かった。

CONCLUSION: The medium-term performance of lithium disilicate is ideal. Ceramic fracture was the most common cause of failure in SCs and FPDs. FPDs presented with the highest failure rate based on evaluation for up to 5 years.