Pulp capping with adhesive resin-based composite vs. calcium hydroxide: a review

The results of some short-term experiments suggest that direct capping of a vital pulp with the modern resin-based composite systems may be as effective as capping with calcium hydroxide. Total cavity etching with 10% phosphoric acid seems to be safe for the exposed pulp, but unless annulled by calcium hydroxide 35% phosphoric acid may be disastrous. For hemostasis and cleaning of the pulp wound both sodium hypochlorite and saline seem suitable, whereas the effectiveness of a 2% chlorhexidine solution is questionable. Although hard-setting calcium hydroxide cements may induce the formation of dentin bridges, they appear not to provide an effective long-term seal against bacterial factors. Within a few years, the majority of mechanically exposed and capped pulps show infection and necrosis due to microleakage of such capping materials and tunnel defects in the dentin bridges. It is unknown whether newer types of resin containing calcium-hydroxide-products will act as a permanent barrier. The cytotoxicity of the resin-based composites and the temperature rise during polymerisation may not be of concern, but microleakage, sensitisation and allergic reactions may pose problems. Based on available data, pulp capping with resin-based composites may be said to be promising, but more and long-term research is mandatory before the method can be recommended.     

Dentin adhesion and microleakage of a resin-based calcium phosphate pulp capping and basing cement

An experimental resin-based bioactive calcium phosphate cement, intended as a pulp capping and basing material, was evaluated for dentin shear bond strength and microleakage. The interfacial morphology was examined by scanning electron microscopy (SEM). For microleakage, dentin cavities without (Group A) or after (Group B) acid etching were restored with the calcium phosphate cement. A resin-based calcium hydroxide (VLC Dycal; Group C) was used as control material according to the manufacturer's instructions. After water storage and thermocycling, the microleakage was scored using a AgNO(3) staining procedure. For the shear bond strength, flat exposed dentin surfaces were treated as for the microleakage test. Metal irises pressed against the dentin surface were filled with the cements, which were photocured. Both tests were carried out after 1 wk. While acid etching did not result in significantly greater microleakage, it led to higher shear bond strength, and allowed, as shown by SEM, the formation of a hybrid layer and resin tags. Both groups treated with the calcium phosphate cement had significantly lower microleakage scores and higher mean shear bond strength values than the groups treated with the control material.     

蚯蚓提取物用于小型猪牙盖髓的实验研究

目的 观察蚯蚓提取物对小型猪牙修复性牙本质形成的作用.方法 用蚯蚓提取物对30颗小型猪牙进行直接盖髓,对照组30颗牙采用氢氧化钙盖髓;分别于术后2、4、12周运用组织病理学方法观察其促进修复性牙本质形成的效果.结果 蚯蚓提取物盖髓后2周,骨样修复性牙本质团块形成,未见到创面周围牙髓变性坏死.盖髓后4周,穿髓孔下有修复性牙本质形成,大部分牙已将穿髓孔封闭.盖髓后12周,穿髓处可见完整的牙本质桥形成,结构致密,髓腔及根管内牙髓组织基本正常.氢氧化钙盖髓组:术后2周界面可见牙髓变性坏死区,有薄层牙本质团块形成,4～12周逐渐形成完整的牙本质桥,形成速度与蚯蚓提取物组相似.结论 本实验提示蚯蚓提取物能促进小型猪牙髓组织损伤的修复,形成修复性牙本质.     

Effect of mineral trioxide aggregate on dentin bridge formation and expression of dentin sialoprotein and heme oxygenase-1 in human dental pulp

This study was conducted to evaluate the pulpal response to direct capping with either mineral trioxide aggregate (MTA) or calcium hydroxide (CH) cement in humans, with a focus on dentin bridge formation and dentin sialoprotein (DSP) and heme oxygenase-1 (HO-1) expression. Direct pulp capping was performed in 20 cases of caries-free human third molars. The pulps were exposed and capped with either MTA or hard-setting CH. After 2 months, the teeth were extracted, and the specimens were prepared for histologic and immunohistochemical evaluations. Histologically, 100% of the MTA group and 60% of the CH group developed dentin bridges. The mean thickness of the dentin bridges observed in the MTA group was statistically greater than that of CH group. In addition, DSP and HO-1 were expressed in the odontoblast-like cells and pulp fibroblasts beneath the dentin bridge; furthermore, significantly greater immunostaining was observed in the MTA group than in the CH group. Collectively, these results indicate that MTA is superior to CH in terms of inducing the dentinogenic process in human pulp capping.     

Response of the pulp of dogs to capping with mineral trioxide aggregate or a calcium hydroxide cement

Abstract – This study was conducted to observe the response of dogs' dental pulp to mineral trioxide aggregate (MTA) and a calcium hydroxide cement when used as pulp capping materials. After the pulps of 30 teeth were exposed, they were capped with either MTA or a calcium hydroxide cement. Histological analysis was performed 2 months after treatment. Results showed a healing process with complete tubular dentin bridge formation and no inflammation in any of the pulps capped with MTA. On the other hand, only five specimens from the calcium hydroxide cement group formed a complete dentin bridge. In this experimental group, pulp inflammation was observed in all but three cases. In conclusion, MTA exhibited better results than the calcium hydroxide cement for the capping of the pulp in dogs.     

Identification of hierarchical factors to guide clinical decision making for successful long-term pulp capping.

OBJECTIVE: Clinicians have few quantitative studies that rank the in vivo pulp capping effects of commonly used restorative materials. These factors were investigated to provide guidance to clinicians. METHOD AND MATERIALS: One hundred sixty-one standardized pulp-exposed cavities were prepared in nonhuman primate teeth. Exposed pulps were capped with calcium hydroxide, resin-modified glass-ionomer cements, and resin composites. Teeth were collected from 7 to 720 days to observe a full range of responses. Pulpal reactions were categorized according to the standards set by the International Standards Organization. Bacteria were detected with McKay's stain. RESULTS: The incidence of bacterial microleakage was 19.7% with resin composite, 21.1% with resin-modified glass-ionomer cement, and 47.0% with calcium hydroxide. The severity of pulpal inflammation increased with the presence of bacteria or tunnel defects. The severity of pulpal inflammation prevented dentinal bridge formation at varying levels: slight for resin composite and resin-modified glass-ionomer cement, and severe with calcium hydroxide. The incidence of severe inflammation or pulpal necrosis was 7.9% with resin composite, 10.6% with calcium hydroxide, and 10.5% with resin-modified glass-ionomer cement. Other variables, such as pulpal exposure width and tertiary dentin formation, were not highly correlated to pulpal inflammation. CONCLUSION: Pulp capping with resin composite provided the lowest incidence of bacterial microleakage, the lowest levels of pulpal inflammation, and the lowest incidence of necrosis.     

年轻恒牙冠折后Ca(OH)_2护髓的疗效观察

目的：观察年轻恒牙釉—牙本质折断后,使用Ｃａ（ＯＨ）２制剂护髓的疗效及影响疗效的因素。方法：对１９８８～１９９５年间因釉—牙本质折断而在北医大口腔医院儿科就诊的５２例（６４个牙）患儿的病历资料进行了临床回顾性分析。其中４８例５９个牙使用Ｃａ（ＯＨ）２制剂进行间接盖髓术护髓。结果：使用Ｃａ（ＯＨ）２间接盖髓,其成功率为７８％;外伤牙的受伤程度及外伤后的就诊时间影响其疗效。结论：年轻恒牙釉—牙本质折断后,使用Ｃａ（ＯＨ）２做护髓剂成功率高     

Direct pulp capping: a review

Abstract The healthy pulp has good healing potential when it is exposed, although the exact repair mechanism is still undetermined, and it is not material-specific. Calcium hydroxide appears to promote the healing process and is the most widely accepted capping material. Paste-type calcium hydroxide formulations are more consistent in promoting healing of pulp exposures than cement forms where bacterial microleakage is eliminated. The prognosis for pulp capping with calcium hydroxide is good if the pulp has no pre-existing symptoms of pain, and the environment provided for it is suitable. This requires the absence of blood clots and bacterial contamination. Where there are some symptoms of pain in a vital tooth, pretreatments with suitable materials improve the prognosis.     

表皮生长因子与胶原蛋白复合物对小型猪修复性牙本质形成作用的实验研究

目的：观察表皮生长因子(Epidermal growth factor,EGF)与胶原蛋白海绵(col1agen sponge,CS)复合物对小型猪修复性牙本质形成的影响。方法：选用实验用小型猪牙齿36颗,采用EGF／CS复合物为材料进行直接盖髓术,通过组织病理学方法常规制备牙-颌骨联合切片,光学显微镜下观察修复性牙本质形成情况,并与氢氧化钙糊剂直接盖髓对照。结果：小型猪牙用EGF／CS直接盖髓术后2周,穿髓孔周边可见修复性牙本质团块形成,团块周围有成牙本质细胞样细胞围绕;术后4周有完整的修复性牙本质桥形成;术后12周修复性牙本质桥增厚且结构致密,严密封闭穿髓孔,桥体近髓腔面形成明显的管样牙本质,下方为整齐排列的典型成牙本质细胞。用氢氧化钙糊剂直接盖髓,术后2周可见穿髓孔处有炎症坏死区,只有少量钙化团块形成,术后4～12周逐渐形成完整的修复性牙本质桥,但形成速度较慢且牙本质桥厚度较薄。结论：EGF与胶原蛋白复合物显著促进牙髓细胞分化和修复性牙本质形成,是一种有临床应用价值的生物活性盖髓剂。     

钙乐(Calar)光固化氢氧化钙盖髓垫底材料的临床应用研究

目的：评价钙乐光固化氢氧化钙（VLC Calar）盖髓垫底的临床效果。方法：在临床选择深龋近髓（61牙），重度楔状缺损（33牙）、深龋穿髓（32牙）和意外穿髓（22牙），用VLC Calar进行垫底及盖髓，并以氢氧化钙制剂作为对照，其上用玻璃离子水门汀垫底，银汞合金或玻璃离子水门汀充填修复。术后半年复查。结果：应用VLC Calar后的成功率为：深龋近髓间接盖髓88.9%，重度楔状缺损间接盖髓95.5%，深龋穿髓直接盖髓52.2%，意外穿髓直接盖髓85.7%，成功率与对照材料无显著性差异，但VLC Calar黏附性好，易充填，能快速固化。结论：钙乐（Calar）光固化氢氧化钙用于间接盖髓及意外穿髓的盖髓效果较好，但用于深龋穿髓的直接盖髓效果较差。     

Pulpal responses to bacterial contamination following dentin bridging beneath hard-setting calcium hydroxide and self-etching adhesive resin system

Abstract –  To evaluate the pulp healing to bacterial contamination beneath a hard-setting calcium hydroxide (DY: Dycal, L.D. Caulk Co.) and a self-etching adhesive resin (2V: Clearfil Liner Bond 2V, Kuraray Medical Inc.) following dentin bridge formation. Class V cavities were prepared on 30 monkey teeth, and the pulps were exposed with a carbide bur through the cavity floor. Each exposed pulp was capped with either DY or 2V. The cavities were restored with a hybrid resin composite. The resin composite was removed at 180 days after capping, and then cavities were left open to the oral environment for 2 weeks to obtain bacteria contamination DY (BDY) and 2V (B2V; n  = 10). A non-bacterial-contaminated group capped with DY was used as control. After bacterial challenges, inflammatory cell infiltration, incidence and differentiation of dentin bridges were evaluated histologically. There were significant differences in the presence of inflammatory cell infiltration among all groups ( P  < 0.05). No moderate or severe inflammatory reaction was found in Group DY. Group BDY showed moderate or severe inflammatory cell infiltration in 50%, and showed four necrotic specimens. Although no statistically significant difference was found in the formation and differentiation of dentin bridges among all groups, tunnel defects in dentin bridges were detected in 70% (DY), 80% (BDY), and 50% (B2V). Group B2V showed a significantly lower presence of inflammatory cell infiltration than Group BDY ( P  < 0.05). Bonding agent is supposed to seal the exposure site, and the remaining bonding agent on the cavities was effective as the barrier in the dentin bridges after bacterial challenges.     

黄连素复合生物膜作小型猪牙直接盖髓的组织学观察

目的：研究应用黄连素复合生物膜对小型猪牙行直接盖髓术的作用。方法：用黄连素复合生物膜做小型猪牙直接盖髓术且与氢氧化钙对照。分别于术后2、4、12周将小型猪快速处死,拔除实验牙及对照牙经、脱钙做组织切片,光镜下观察。结果：术后2周,实验组有修复性牙本质团块形成,术后4、12周,有牙本质桥形成,在髓腔侧有排列整齐的成牙本质细胞,牙髓无明显炎症,无变性,牙周组织正常,牙髓保存下活力。结论：黄连素复合生物膜对小型猪牙有良好的直接盖髓作用。     

MTA and calcium hydroxide for pulp capping

This study evaluated the biocompatibility of mineral trioxide aggregate (MTA) after direct capping of exposed pulp tissue in dog's teeth. Class I cavities were prepared in 26 teeth from 3 adult dogs. MTA was applied over the exposed pulp in 13 teeth and paste of calcium hydroxide plus distilled water (control) was applied in the remaining 13 teeth. After 90 days, the animals were killed; the maxilla and mandible were dissected and sectioned to obtain individual roots. The samples were processed histologically. The pulp and periapical response observed with the use of MTA was similar to that of calcium hydroxide paste. In all specimens, there was a dentin bridge obliterating the exposure, an intact odontoblastic layer, no inflammatory cells, normal connective pulp tissue, normal apical and periapical regions and no bone tissue changes. Similar to calcium hydroxide, MTA presented excellent response when used for direct pulp capping.     

可乐丽菲露SE BOND用于直接盖髓术的组织学评价

目的:对可乐丽菲露SEBOND在人体用于直接盖髓术进行组织学评价。方法:选择24名志愿者共45颗健康人第三磨牙,41颗在牙合面制备Ⅰ类洞并在洞底作人工穿髓孔,然后分为2组,实验组以可乐丽菲露SEBOND盖髓,对照组以氢氧化钙盖髓。4颗作为空白对照。所有实验牙齿分别在盖髓后的7、30、90d后拔除并进行组织学检测。结果:实验组和对照组志愿者均未出现术后实验牙齿敏感症状。病理检测显示,在7d和30d的观察期内2组均有轻度到中度的炎性反应,但可乐丽菲露SEBOND组的炎性反应较氢氧化钙组轻,其组织学评价分级上的差别有统计学意义(P<0.05)。在90d的观察期内2组均无明显的炎性反应,而牙本质桥的形成在氢氧化钙组显著多于可乐丽菲露SEBOND组,氢氧化钙组7例标本中有6例标本有牙本质桥的形成,可乐丽菲露SEBOND组7例标本中有3例形成,其差别有统计学意义(P<0.05)。结论:可乐丽菲露SEBOND对牙髓的刺激性较小,但诱导牙本质形成的能力较氢氧化钙弱。     

Histopathological and immunohistochemical study on the effects of a direct pulp capping experimentally developed adhesive resin system containing reparative dentin-promoting agents

The studies so far conducted by our colleagues in relation to dental pulp capping using adhesive resins revealed that the adhesive resins are useful for capping exposed pulps but are a little slower to take effect on the injured pulp tissue during the initial stage: up to 90-days after pulp exposure, compared with calcium hydroxide and its preparations. In the present study, an experimentally developed adhesive resin system was applied in direct pulp capping and restoration and the healing process was examined histopathologically and immunohistochemically. The resin system was manufactured with calcium phosphate added into the bonding material for the purpose of accelerating the healing process. The largest amount of reparative dentin was formed by SE5 (whitlockite 5 wt%), followed by SE9 (hydroxyapatite 5 wt%, whitlockite 5 wt%), SE1 (hydroxyapatite 5 wt%), and SE2 (hydroxyapatite 10 wt%). Generally, it could be said that the experimental groups using whitlockite and hydroxyapatite had the tendency to produce a larger amount of reparative dentin.     

Histopathologic study on pulp response to single-bottle and self-etching adhesive systems

This study compared the pulp response to seven adhesive resins (three single-bottle and four self-etching primers) and their companion resin composite systems with a commercial calcium hydroxide material when applied to exposed monkey pulps. The control group was capped with Dycal (DY), while the experimental groups were capped with one of the following adhesive resin systems: AQ Bond (AQ), Single Bond (SB), Imperva Fluorobond (IF), One Step (OS), Prime&Bond NT (PBNT), Perme Bond F (PBF) and One-up Bond F (OBF). Histopathologic evaluation of pulp tissue disorganization, inflammatory cell infiltration, reparative dentin formation and bacterial penetration at the 3rd, 30th and 90th post-operative days was done using light microscopy. Data were analyzed using the Kruskal-Wallis test followed by the Least Significant Difference Test to determine differences between the control group and the experimental groups at each observation period. The correlation of inflammatory cell infiltration and bacterial presence was investigated by the Kendall correlation analysis. All tests were performed at a 95% level of confidence. The pulpal responses of groups DY, SB, OS, PBF and OBF were generally characterized by none-to-mild pulp tissue disorganization and inflammatory cell infiltration. Also, initiation of reparative dentin formation was found earlier in Group DY, resulting in more complete dentin bridges at the 30- and 90-day observation periods. Groups AQ, IF and PBNT had significantly more inflammatory cell infiltration and a lower incidence of reparative dentin formation than Group DY. A significant correlation was detected between inflammatory cell infiltration and the presence of bacteria. It is concluded that the pulp response to SB, OS, PBF and OBF is not significantly different from the calcium hydroxide preparation. However, calcium hydroxide capping resulted in a higher incidence and faster rate of reparative dentin formation.     

富血小板血浆用于犬牙直接盖髓的实验研究

目的:观察富血小板血浆(platelet-rich plasma,PRP)直接盖髓后修复性牙本质的形成。方法:成年雄性健康杂种犬2只,分别取静脉血制备PRP后,选取每只犬的所有切牙,尖牙和前磨牙共48个牙作为对象,于颈部制作穿髓模型后,按拆分口设计原则随机分为6组(MTA、Dycal、MTA+PRP、Dycal+PRP、PRP、空白),分别用相应盖髓剂进行直接盖髓治疗,3个月后应用牙科CT观察各组穿髓处硬组织和牙本质桥形成情况。结果:实验3个月后,MTA,MTA+PRP,Dycal+PRP组修复性牙本质形成的效果均优于单纯氢氧化钙组(Dycal)。PRP组、空白组无完整的牙本质桥形成。结论:PRP+Dycal能促进犬富血小板血浆牙髓组织修复,是一种很有希望的复合型生物盖髓剂。     

pH values of pulp-capping agents

Calcium hydroxide has been used extensively in dentistry. Few investigators have reported the pH values of pulp-capping agents containing calcium hydroxide. The purpose of this study was to evaluate pH levels of eight pulp capping agents containing calcium hydroxide. The results indicate that the pH values of five capping agents tested are neutralized by the dentin wall, but that three of these capping agents are not neutralized.     

Risk aspects of dental restoratives: From amalgam to tooth-colored materials

Dental materials’ choice of patients has considerably changed. Whereas cast gold and amalgam have been the predominant biomaterials for decades, today tooth-colored materials like resin-based composites and ceramics are more and more successful. However, are we going to replace a good but biologically questionable material (amalgam) with an equal material (resin composite) being more esthetic but also biologically questionable For amalgam, long-term clinical studies reported some significant hints that in single cases amalgam may be a health hazard for patients, finally Norway banned amalgam completely. The main advantage of a resin-based composite over amalgam is its tooth-like appearance and more or less absence of extensive preparation rules. For many years it was believed that resin-based composites may cause pulpal injury. However, pulpal injury associated with the use of resin-based composites is not correlated with their cytotoxic properties. Nevertheless, resin-based composites and other dental materials require rigorous safety evaluation and continuous monitoring to prevent adverse events similar like with amalgam. Because of non-biocompatible pulp responses to resin-based composites and amalgam, they should not be placed in direct contact with the dental pulp. The less dentin remaining in the floor of preparations between resin-based composites or other dental materials is more likely to cause pulpitis. Percentage of patients and dental practitioners who display allergic reactions is between 0.7% and 2%. The release of cytotoxic monomers from resin-based materials is highest after polymerization and much lower after 1 wk. Substances released from resin-based composites have been shown to be toxic in cytotoxicity tests. Nevertheless, in vitro cytotoxicity assays have shown that amalgam has greater toxic effects than resin-based composites, sometime 100-700-fold higher. Altogether, the risk of side-effects is low, but not zero, especially for dental personnel.     

Long-term evolution of a case of direct pulp capping by adhesion to dentin.

This article presents the long-term follow-up of a female patient who suffered pulp exposure during removal of a large caries lesion from the mandibular right first molar. The clinical decision to perform direct pulp capping was made. The tooth was treated with 5% chlorhexidine, etched with 37% phosphoric acid, and then restored with Heliomolar composite after application of Gluma dentin adhesive. The patient was followed for more than 8 years.