不完全齲蝕除去後の深在性齲蝕病変の臨床的、微生物学的、およびX線学的研究

A clinical, microbiologic, and radiographic study of deep caries lesions after incomplete caries removal.

抄録

目的:

不完全齲蝕象牙質除去および歯牙封鎖後の深在性齲蝕病巣の臨床的、X線学的および微生物学的変化を評価した。

OBJECTIVE: Clinical, radiographic, and microbiologic changes in deep caries lesions were assessed after incomplete carious dentin removal and tooth sealing.

方法および材料:

深在性う蝕病変を有する32歯を対象とした。治療は、脱灰象牙質の不完全な掘削、水酸化カルシウムの塗布、および6～7ヵ月間の封鎖であった。象牙質の色と硬さを臨床的に評価した。X線写真の密度の差は、デジタル画像サブトラクションにより評価した。仮封前と実験期間後に、脱灰象牙質から微生物学的サンプルを採取した。サンプルは、好気性および嫌気性条件下の血液寒天培地、Mitis Salivarius寒天培地、およびRogosa選択的乳酸菌寒天培地で培養した。

METHOD AND MATERIALS: Thirty-two teeth with deep caries lesions were studied. Treatment consisted of incomplete excavation of the demineralized dentin, application of calcium hydroxide, and sealing for a 6- to 7-month period. The color and consistency of the dentin were clinically assessed. Differences in radiographic density were assessed by digital image subtraction. Microbiologic samples were obtained from the demineralized dentin before the temporary sealing and after the experimental period. The samples were cultivated on blood agar under aerobic and anaerobic conditions, in Mitis Salivarius agar, and Rogosa selective Lactobacillus agar.

結果:

1例は歯髄壊死を呈していた。もう1症例は、プロビジョナルシール除去時に歯髄露出が認められた。すべての歯において、初期の脱灰象牙質は軟らかく湿潤しており、1病巣は黄色、21病巣は淡褐色、8病巣は暗褐色であった。治療後、象牙質は乾燥し、80.00%が硬く、16.67%がleathery、3.33%が軟らかいままであった。象牙質は5歯で淡褐色，25歯で暗褐色であった．X線写真の密度（ピクセル強度）は、対照区で88.77±7.02、試験区で94.66±6.75と、統計的に有意な平均差が認められた。嫌気性菌、好気性菌、乳酸菌、ミュータンス連鎖球菌の数は、治療終了時までに有意に減少した。

RESULTS: Two cases were lost during the study; one presented pulpal necrosis. In the other case, there was pulpal exposure during removal of provisional sealing. In all teeth, the initial demineralized dentin was soft and wet; one lesion was yellow, 21 were light brown, and eight were dark brown. After treatment, the dentin was dry, and 80.00% of specimens were hard, 16.67% were leathery, and 3.33% remained soft. The dentin was light brown in five teeth and dark brown in 25. There was a statistically significant mean difference in radiographic density (pixel intensity), 88.77 +/- 7.02 in the control areas and 94.66 +/- 6.75 in the test areas. The counts of anaerobic and aerobic bacteria, lactobacilli, and Streptococci mutans had decreased significantly by the end of treatment.

結論:

う蝕象牙質の不完全な除去およびその後の歯の封鎖は、病変の停止をもたらしたことから、う蝕病変の制御には象牙質病変の完全な除去は必須ではないことが示唆された。

CONCLUSION: Incomplete removal of carious dentin and subsequent tooth sealing resulted in the arrest of the lesions, suggesting that complete dentinal caries lesion removal is not essential to the control of caries lesions.