Management of teeth with open apices and necrotic pulps with single visit apexification: 3 representative cases

Apexification is the most widely accepted procedure for the treatment of nonvital immature teeth. Single visit apexification is less time consuming, more economical and an easily acceptable technique with the aim of inducing the formation of a hard tissue barrier, thus allowing proper condensation of gutta percha in the root canal. Factors considered during this procedure are: i. Debridement of root canal minimizing the infection and filling the root canal space with resorbable calcification inducing material i.e. Ca(OH)2. ii. Minimal mechanical intervention to maintain the integrity and vascularity of apical region. Once filled, Ca(OH)2 was not changed again and the treated tooth was examined only radiographically till the desired apical closure was achieved. Three representative cases treated with this single visit apexification technique are discussed here. In all the cases successful apical closure of different types was achieved. Treatment was then concluded with gutta percha obturation in all the cases with successful follow up.     

恒前牙冠折露髓部分切髓术的疗效分析

目的：观察恒前牙冠折露髓部分切髓术的疗效。方法：选择26例31牙外伤冠折不超过72h的恒前牙,进行部分冠髓切除术。分别于术后15d、1个月、3个月、6个月、1年、2年进行临床和X线检查。结果：成功29牙,失败2牙,成功率93．5％。失败原因为根管内吸收和暂补料脱落再感染。结论：冠髓部分切除术较根管口部分活髓切断术有许多优点,是一种良好的治疗方法。临床上需严格掌握适应证和操作规程,以提高成功率。     

Evaluation of fracture resistance in simulated immature teeth using resilon and ribbond as root reinforcements – An in vitro study

Abstract – Background/Aim: To compare the reinforcement and strengthening ability of resilon, gutta‐percha, and ribbond in endodontically treated roots of immature teeth. Material and Methods: Sixty five freshly extracted human maxillary anterior teeth were prepared with a Peeso no. 6 to simulate immature teeth (Cvek’s stage 3 root development). After instrumentation, each root was irrigated with sodium hypochlorite and with ethylene diamino tetra acetic acid to remove the smear layer. To simulate single visit apexification technique a 4–5 mm white Pro Root mineral trioxide aggregate plug was placed apically using schilder carrier. The teeth were divided into three experimental groups and one control group. Group I – control group (root canals instrumented but not filled); Group II – backfilled with thermoplastisized gutta‐percha using AH plus sealer; Group III – reinforced with Resilon using epiphany sealer; Group IV – reinforced with Ribbond fibers using Panavia F luting cement. A Universal Testing Machine was used to apply a load, at the level of the lingual cementoenamel junction with a chisel‐shaped tip The peak load to fracture was recorded and statistical analysis was completed using student’s t‐test. Results: Values of peak load to fracture were 1320.8, 1604.88, 1620, and 1851newtons for Group I to Group IV respectively. The results of student’s t‐test, revealed no significant difference (P > 0.05,) between Group II and Group III. Comparison between Group IV and Group III and between Group IV and Group II revealed highly significant difference (P > 0.001). Conclusions: Teeth reinforced with Ribbond fibers using Panavia F luting cement showed the highest resistance to fracture. Resilon could not strengthen the roots and showed no statistically significant difference when compared with thermopasticised gutta‐percha in reinforcing immature tooth when tested with universal testing machine in an experimental model of immature tooth.     

Vitapex糊剂充填根管的临床研究

目的 观察Vitapex糊剂充填根管的疗效，探讨其最适宜的使用方法。方法 将490例慢性根尖周炎随机分为5组，A，B，C，D为实验组，使用Vitapex糊剂，分别用下列方法进行根充；A组，一次法，加牙胶尖；B3组,一次法，不加牙胶尖；C组，二次法，加牙胶尖；D组，二次法，不加牙胶尖。E为对照组，用常规根管充填剂加牙胶法，二次法根充。结果 1年后复查，B组有效率显著低于其他各组（P＜0．05），且A，B，两组的治愈率低于另外三组（P＜0．05）。结论 Vitapex是一种理想的根管充填材料，二次法根充，不加牙胶尖为其最适宜使用方法。     

Successful endodontic treatment of dens in dente

The dens in dente is a developmental variation which is thought to arise as a result of an invagination in the surface of a tooth crown before calcification has occurred. This report is a case which documents the successful non surgical endodontic treatment permanent tooth with dens in dente by periodical dressing the intracanal space with calcium hydroxide for a year and follow up after permanent filling-for one and a half years. After a sign of repair around the periapical area had occurred, the canal was filled with warm gutta percha technique. The importance of early and corrected diagnosis, the possible significance of even a small and noncarious dens in dente, and the treatment of anomaly were emphasized.     

Stress distributions in internal resorption cavities restored with different materials at different root levels: A finite element analysis study

The aim of this study was to evaluate the stresses within simulated roots with internal resorption cavities at the apical, middle and coronal root levels, after obturation with gutta‐percha and/or MTA utilising finite element analysis (FEA). Mandibular premolar teeth with internal resorption cavities at different root levels were modelled. Models were restored with gutta‐percha and/or MTA. An oblique force of 300 N was applied and stress evaluations were carried out. In the MTA‐filled resorption models, the stresses were distributed more homogeneously than the gutta‐percha filled models, and the stress concentrations were lower in the remaining dentinal tissues. If the whole root is considered, the fully gutta‐percha‐filled models generated the highest stress values. Differences between the fully MTA‐filled models and hybrid techniques were present only in the apical resorption models. Both the MTA and combination of MTA and gutta‐percha can be suggested for use in clinical practice, in cases of internal root resorption cavity obturation.     

Displacement of maxillary right second premolar caused by gutta percha filling in corresponding primary molar

Background

For pulp therapy in primary teeth, commonly performed in daily clinical practice, calcium hydroxide paste is widely used as a root canal filling material and typically resorbed by the permanent successor upon its emergence into the oral cavity.

The effect of calcium hydroxide root filling on dentin fracture strength

Abstract –  This in vitro study measured the effect of calcium hydroxide root filling on the microtensile fracture strength (MTFS) of teeth. A total of 40 extracted human disease-free permanent maxillary incisors were hand and rotary instrumented and vertically compacted with United States Pharmacopeia (USP) calcium hydroxide. The teeth were stored in a moist environment for 7, 28, and 84 days. As a control group, 10 teeth were vertically compacted with gutta percha and sealer. The MTFS of the teeth was measured (Mpa) using an Instron machine. Data were assessed statistically using an unpaired t -test ( P value). The intracanal placement of calcium hydroxide weakened the MTFS of teeth by 13.9 Mpa per 77 days: an average of 0.157 MPa day⁻¹. Between 7 and 84 days, the MTFS of the dentin was reduced by 43.9%. This difference was statistically significant ( P  < 0.05). A statistical difference ( P  < 0.05) was observed between the mean MTFS of the calcium hydroxide-filled dentin between 7 days (45.7 MPa) and 28 days (35.6 MPa) and also between 7 and 84 days (31.8 MPa). There was also a significant difference ( P  < 0.05) between the MTFS of the calcium hydroxide-filled dentin after 84 days (31.8 MPa) and the gutta percha-filled dentin (41.3 MPa) when used as a control root filling material. The weakening of the dentin by 23–43.9% following root canal filling with calcium hydroxide provides compelling evidence to re-evaluate the daily usage of this material in endodontic therapy.     

Analysis of the healing process in delayed tooth replantation after root canal filling with calcium hydroxide,Sealapex and Endofill: a microscopic study in rats

Abstract – The major concern in the therapeutics of tooth replantation refers to the occurrence of root resorption and different approaches have been proposed to prevent or treat these complications. The purpose of this study was to evaluate tissue response to delayed replantation of anterior rat teeth treated endodontically using calcium hydroxide, Sealapex, and Endofill without the placement of gutta‐percha cones. Thirty rats had their right upper incisor extracted and maintained in dry storage for 60 min. After removal of the dental papilla, enamel organ, pulp tissue, and periodontal ligament remnants, the teeth were immersed in 2% sodium fluoride phosphate acidulated, pH 5.5, for 10 min. The root canals were dried with absorbent paper points and the teeth were assigned to three groups (n = 10) according to the filling material. Group I – calcium hydroxide and propyleneglycol paste, Group II – Sealapex, and Group III – Endofill. The sockets were irrigated with saline and the teeth were replanted. Replacement resorption, inflammatory resorption and ankylosis were observed in all groups. Although the occurrence of inflammatory resorption was less frequent in Group I, there were no statistically significant differences among the groups. It may be concluded that compared to the paste, filling the root canals with Sealapex and Endofill sealers without the placement of gutta‐percha cones did not provide better results.     

Vitapex根管充填材料的短期疗效观察

目的 :比较氧化锌丁香油糊剂加牙胶尖、Vitapex糊剂加牙胶尖两种根管充填材料的短期疗效。方法 :131例门诊就诊患者的 16 1个患牙随机分为 2组 ,其中 82个牙用氧化锌丁香油糊剂加牙胶尖进行根管充填 ,79个牙用Vitapex糊剂加牙胶尖进行根管充填 ,术后 3、6个月随访观察。结果 :术后 3个月复查 ,发现氧化锌丁香油糊剂加牙胶尖组和Vitapex糊剂加牙胶尖组的有效率分别为 80 .3%和 93.1% ,有显著统计学差异(P <0 .0 5 )。术后 6个月复查 ,发现氧化锌丁香油糊剂加牙胶尖组和Vitapex糊剂加牙胶尖组的有效率分别为82 %和 95 % ,也有显著统计学差异 (P <0 .0 5 )。结论 :Vitapex根管充填糊剂是一种短期疗效较好的根管充填材料     

Endomethasone根充糊剂用于去髓术、根管治疗术一次法的近期疗效

目的：比较Endomethasone根管充填糊剂加牙胶尖、传统根管充填剂加牙胶尖在去髓术、根管治疗术一次法根管充填术后的急性反应及近期疗效.方法：选择活髓患牙和适合行去髓术、根管治疗术一次法的患牙共678个,随机分为2组,根管预备后实验组和对照组分别采用Endomethasone糊剂加牙胶尖、根管充填剂加牙胶尖充填根管.观察2组患牙术后1周内的急性反应及术后3、6个月的疗效.结果：实验组去髓术根充后急性反应率显著低于对照组（P＜0.01）;实验组根管治疗术根充后急性反应率显著低于对照组（P＜0.05）.实验组和对照组中,单根管患牙在去髓术、根管治疗术根充后急性反应率均显著低于多根管患牙（P＜0.01）.术后3、6个月复查,实验组去髓术、根管治疗术疗效均稍高于对照组,但无显著差异（P＞0.05）.结论：在去髓术、根管治疗术一次法中,Endomethasone糊剂充填根管较根管充填剂可有效地减少术后急性反应的发生.但在近期疗效上两者无明显差异,长期疗效有待进一步观察.     

Leakage along warm gutta-percha fillings in the apical canals of curved roots

Abstract – The aim of this study was to investigate the leakage along the apical portion of warm gutta‐percha obturated curved canals. Human mandibular premolars with single, curved (21°–40°) canals were prepared using the Lightspeed technique. Two groups of prepared canals, matched according to curvature and prevalence of apical transportation, were obturated by two techniques. Coronal gutta‐percha was removed immediately after root obturation was completed to simulate the procedure for post space preparation. Leakage along the apical 3 mm of root filling was measured with a fluid transport device. Vertical condensation of warm gutta‐percha and Pulp Canal Sealer provided less leakage than Thermafil plastic obturators and AH26 sealer (P=0.002).     

Apexification & apexogenesis.

When there is pulpal involvement of permanent teeth with incompletely formed roots, techniques for the induction of apical closure should be completed before endodontic therapy is begun. Apexification is a method of inducing a calcified barrier at the apex of a nonvital tooth with incomplete root formation. Apexogenesis refers to a vital pulp therapy procedure performed to encourage physiological development and formation of the root end.     

Push‐out bond strength of gutta‐percha with a new bioceramic sealer in the presence or absence of smear layer

The purpose of this study was to compare the bond strength of a new bioceramic sealer (EndoSequence BC Sealer) and AH Plus in the presence or absence of smear layer. Extracted single‐rooted human teeth were prepared and randomly divided into four groups. In groups 1 and 3, the root canals were finally irrigated with 5.25% NaOCl and smear layer was not removed, but in groups 2 and 4, the root canals were finally irrigated with 17% EDTA followed by 5.25% NaOCl in order to remove the smear layer. In groups 1 and 2, the root canals were obturated with gutta‐percha/AH Plus, but in groups 3 and 4, obturation was performed with gutta‐percha/EndoSequence BC Sealer. Push‐out bond strength and failure modes were evaluated. The bond strength of gutta‐percha/AH Plus and gutta‐percha/EndoSequence BC Sealer was not significantly different (P = 0.89). The presence or absence of smear layer did not significantly affect the bond strength of filling materials (P = 0.69). The mode of bond failure was mainly cohesive for all groups. In conclusion, the bond strength of the new bioceramic sealer was equal to that of AH Plus with or without the smear layer.     

年轻恒前牙冠折损伤程度和露髓时间对活髓切断术疗效的影响

目的：对外伤引起的年轻恒前牙冠折露髓行活髓切断术，并于2年以上追踪观察其根管、根尖孔发育情况。方法：72例外伤冠折露髓牙，采用活髓切断术切断冠部牙髓，保留根髓活力，促进牙根发育。结果：72例患牙中，轻度损伤58例，治疗成功率为93．1％；重度损伤14例，成功率为64．2％，总成功率为87．5％。结论：活髓切断术是外伤冠折露髓的首选治疗方法。     

Effect of customization of master gutta-percha cone on apical control of obturation using different techniques: an in vitro study

Aims (i) To compare the prevalence of root filling extrusion placed using three different obturation techniques, each with or without customization of the master gutta‐percha cone; and (ii) to investigate the effects of various factors on the prevalence of root filling extrusion. Methodology A total of 180 roots were selected and randomly allocated into three groups. Five general dental practitioners were recruited; each obturated one group of the roots using three techniques, namely cold lateral condensation (n = 20), Schilder's warm vertical condensation (n = 20) or continuous wave condensation (n = 20). Each technique was completed with (n = 10) or without (n = 10) customization of the master gutta‐percha cone using chloroform. Two groups of the roots were recycled to allow all five operators to use them. Two observers examined the preinstrumentation, working length, master apical file and postobturation radiographs, and determined the presence of root filling extrusion and voids independently; they were blinded regarding the obturation technique used. The presence of root filling extrusion was also assessed by inspecting the root apex after obturation. The data were analysed using logistic regression models. Results A total of 300 root fillings were performed and 291 were included for analysis. Most of the root fillings were placed within 0.5 mm of the working length (80%, n = 233); only 20% (n = 58) were placed >0.5 mm beyond the working length. The odds of prevalence of extrusion >0.5 mm were significantly reduced by approximately 50% when cold lateral condensation (OR = 0.50; 95% CI = 0.26, 0.99; P = 0.04) or customization of master gutta‐percha cone (OR = 0.55; 95% CI = 0.30, 0.99; P = 0.04) was used. One operator produced 2.5 times more extruded root fillings than the other operators (OR = 2.50; 95% CI = 1.31, 4.78; P = 0.006). Other factors, such as root canal curvature and length, apical size of the prepared canal, as well as the operator's preferred obturation technique, were shown to have no significant influence on the prevalence of extrusion. Conclusions The prevalence of extrusion was significantly lower when cold lateral condensation and customization of the master cone were used. The ‘operator’ emerged as a significant factor affecting the prevalence of root filling extrusion.     

儿童恒前牙冠折后牙髓活力的保存方法

目的：探讨儿童恒前牙冠折后不同受损程度牙髓活力的保存方法。方法：采用三种方法对不同受损程度的72例98个冠折恒前牙牙髓进行处理，并定期复查。结果：对14个单纯性釉质折断牙牙髓随访2年，牙髓活力不受影响；对23个牙本质折断但未露髓患牙护髓后2年成功率为82.6%，对61个牙本质折断并露髓患牙采取活髓切断术，其2年成功率为81.9%。结论：对损伤程度不同的冠折牙牙髓应采取不同的治疗方法；活髓切除术不仅适用于年轻恒牙，对于牙根已形成但仍处于儿童暑期的恒前牙同样适用；牙本质桥的形成并不意味其下方的牙髓组织正常。     

Mineral trioxide aggregate pulpotomies: a case series outcomes assessment

BACKGROUND: The greatest threats to developing teeth are dental caries and traumatic injury. A primary goal of all restorative treatment is to maintain pulp vitality so that normal root development or apexogenesis can occur. If pulpal exposure occurs, then a pulpotomy procedure aims to preserve pulp vitality to allow for normal root development. Historically, calcium hydroxide has been the material of choice for pulpotomy procedures. Recently, an alternative material called mineral trioxide aggregate (MTA) has demonstrated the ability to induce hard-tissue formation in pulpal tissue. The authors describe the clinical and radiographic outcome of a series of cases involving the use of MTA in pulpotomy procedures. METHODS: Twenty-three cases in 18 patients were treated with MTA pulpotomy procedures in an endodontic private practice. All of the patients had been referred to the practice for diagnosis and treatment of a symptomatic tooth. All of the authors provided treatment. Pulpal exposures were either due to caries or complicated enamel dentin fractures. RESULTS: Nineteen teeth in 14 patients were available for recall. The mean time of recall was 19.7 months. Of the 19 cases, 15 involved healed teeth, and three involved teeth that were healing. One of 19 cases involved a tooth with persistent disease. CONCLUSIONS: MTA may be useful as a substitute for calcium hydroxide in pulpotomy procedures. Further research, however, is required to clarify this conclusion. CLINICAL IMPLICATIONS: MTA conceivably could replace calcium hydroxide as the material of choice for pulpotomy procedures, if future research continues to show promising results.     

Cvek pulpotomy: report of a case with five-year follow-up

Partial pulpotomy (Cvek pulpotomy) is the treatment of choice for injured permanent incisor teeth with exposed vital pulp tissue and immature apices. This treatment preserves pulpal function, thus allowing continued root development. The present report describes the case of a permanent incisor with incomplete root end closure that underwent a Cvek pulpotomy, with subsequent apical closure. Five years post pulp therapy, the tooth remained symptom free.     

Accuracy of two root canal length measurement devices integrated into rotary endodontic motors when removing gutta-percha from root-filled teeth

Aim To evaluate ex vivo the accuracy of the integrated electronic root canal length measurement devices within TCM Endo V^® and Tri Auto ZX^® motors whilst removing gutta‐percha and sealer from filled root canals. Methodology Forty freshly extracted maxillary and mandibular incisor teeth with mature apices were selected. Following access cavity preparation, the length of the root canals were measured visually 0.5 mm short of the major foramen (TL). The canals were prepared using the HERO 642 system and then filled with gutta‐percha and AH26 sealer using a lateral compaction technique. After 7 days the coronal temporary filling was removed and the roots mounted in an alginate experimental model. The roots were then randomly divided in two groups. The access cavities were filled with chloroform to soften the gutta‐percha and allow its penetration using the Tri Auto ZX^® and the TCM Endo V^® devices in groups 1 and 2, respectively. The ‘automatic apical reverse function’ (ARL) of both devices was set to start at the 0.5 setting and the rotary instrument inserted inside the root canal until a beeping sound was heard and the rotation of the file stopped automatically. Once the auto reverse function had been initiated, the foot pedal of the motor was inactivated and the rubber stop placed against the reference point. The distance between the file tip and rubber stop was measured using a digital calliper to 0.01 mm accuracy (ARL). Then, a size 20, 0.02 taper instrument was attached to each device and inserted into the root canals without rotary motion until the integrated ERCLMDs positioned the instrument tips at the 0.5 setting as suggested by the devices. This length was again measured using a digital calliper (EL). The Mann–Whitney U‐test was used to investigate statistical differences between the true canal length and those indicated by the two devices when used in ‘automatic ARL and when inserted passively (EL). Results In the presence of gutta‐percha, sealer and chloroform, the auto‐reverse function for the Tri Auto ZX^® and TCM Endo V^®, set to start at 0.5 level, was initiated beyond the foramen in 60% and 95% of the samples, respectively during active (rotary) penetration of the instruments. There was a statistically significant difference between the devices for the mean discrepancies between the length at which the auto reverse function was initiated and the true length (P < 0.001). Electronic detection of the apical terminus when the instruments were introduced passively (not rotating) was beyond the foramen in 20% and 37% of cases in the Tri Auto ZX^® group and the TCM Endo V^® group, respectively. There was a statistically significant difference between the devices for the mean discrepancies between the electronically determined (passive) length and true length (P < 0.01). Conclusion The auto reverse function of the Tri Auto ZX^® and TCM Endo V^® devices, set to start at 0.5 level, were initiated beyond the foramen in the majority of root‐filled teeth during active (rotating) penetration of root filling material. Thus, this automatic function must be used with caution when removing gutta‐percha root fillings. There were significant differences between the accuracy of measurements in active (rotating) and passive (not‐rotating) modes; both devices were more accurate when used in passive mode. However, the Tri AutoZX^® was significantly more accurate in a greater proportion of cases.