|Year : 2018 | Volume
| Issue : 2 | Page : 173-180
Zinc oxide eugenol and Endoflas pulpectomy in primary molars: 24-month clinical and radiographic evaluation
Jayalakshmi Pandranki, Narsimha Rao V Vanga, Srinivas Kumar Chandrabhatla
Department of Pedodontics and Preventive Dentistry, GITAM Dental College, Visakhapatnam, Andhra Pradesh, India
|Date of Web Publication||2-Jul-2018|
Department of Pedodontics and Preventive Dentistry, GITAM Dental College and Hospital, Visakhapatnam - 530 045, Andhra Pradesh
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Context: Despite modern advancement in material and technical aspect, management of infected primary molars is of prime concern in pediatric endodontics. An effective root canal material plays the major role in achieving the fluid impervious seal by defending against variant microflora and maintaining the tooth in function for longer duration. Aims: This study aims to evaluate and compare the success of endoflas as root canal filling material in infected primary molars with zinc oxide eugenol (ZOE). Materials and Methods: Primary molars with necrotic pulp in healthy, cooperative children were selected. Ethical clearance and informed consent was obtained. Standardized pulpectomy procedure was done and root canals were filled with either ZOE or endoflas. Further follow-up with clinical and radiographic evaluation was carried at 0, 3, 6, 12, and 24 months. The findings obtained were statistically analyzed using Chi-square test. Results: Endoflas showed acceptable results as root canal filling material in primary molars even at 2-year follow-up, though overfilling of root canals led to low success rate compared to teeth with combined optimal and under fillings. There was no significant difference between the two materials (P > 0.05). Conclusions: Endoflas could be a potential alternative to ZOE for preserving infected primary molars.
Keywords: Endoflas, infected primary molars, pulpectomy, zinc oxide eugenol
|How to cite this article:|
Pandranki J, V Vanga NR, Chandrabhatla SK. Zinc oxide eugenol and Endoflas pulpectomy in primary molars: 24-month clinical and radiographic evaluation. J Indian Soc Pedod Prev Dent 2018;36:173-80
|How to cite this URL:|
Pandranki J, V Vanga NR, Chandrabhatla SK. Zinc oxide eugenol and Endoflas pulpectomy in primary molars: 24-month clinical and radiographic evaluation. J Indian Soc Pedod Prev Dent [serial online] 2018 [cited 2022 May 22];36:173-80. Available from: https://www.jisppd.com/text.asp?2018/36/2/173/235674
| Introduction|| |
Adequate management of pulpally infected primary dentition can be attained through pulpectomy, thereby preventing esthetic, phonetic, or functional problems.
The ideal root canal filling material for the primary teeth should fill the root canals easily and adhere to their walls. It should not shrink and resorb at a similar rate as the primary root. It should be harmless to the developing tooth germ, biocompatible to the periradicular tissues, and also resorb readily when extruded beyond the apex. None of the currently available materials meets all of these criteria.,,,,
Zinc oxide eugenol (ZOE), being traditional and commonly used root canal filling material, showed varied success rate in infected primary teeth (65%–92.3%)., Hitherto, the resorption pattern of ZOE has attended with obnoxious sequel such as foreign body reaction, deviation of successor's eruption. Literature has revealed 100% success rate with calcium hydroxide and iodoform-based pastes.,, However, hollow tube effect was reported due to intraradicular depletion ,, of this material ahead of physiological resorption, etc. Hence, there is a paucity in the scientific literature to support the use of conventional obturating materials in spite of their continued clinical success.
Endoflas, manufactured by Sanlor and Cia. S. en C.S., Colombia, South Africa, constitutes the combination of 40.6% triiodide and iodine dibutilorthocresol, 56.5% zinc oxide, 1.07% calcium hydroxide, and 1.63% barium sulfate in powder and consists of eugenol and paramonochlorophenol as liquid. The popularity of endoflas as root canal filling material has increased rapidly in pediatric dentistry over the past few years. Its antimicrobial efficacy disinfects dentinal tubules and accessory canals that are hard-to-reach mechanically. Its resorbable nature is limited to the excess extruded extraradicularly without intraradicular wash out. Its hydrophilic property aids in filling even mildly humid canals. Literature have revealed excellent healing capabilities and bone regeneration characteristics of endoflas with 95%–100% success outcome, but the follow-up period was limited to 9 months.,
Hence, the rationale of the present study was to evaluate and compare success of endoflas as root canal filling material in infected primary molars against ZOE and also evaluate the ability of the endoflas material to sustain the infected primary molars in functionally stable state, providing hermetic seal of the root canal system, and biologically safe environment to the surrounding tissues.
| Materials and Methods|| |
Forty-four healthy children who attended to the Department of Pedodontics and Preventive Dentistry, GITAM Dental College, Visakhapatnam, Andhra Pradesh, within the age group of 4–9 years, having one or more carious primary teeth were evaluated and considered as candidates for inclusion if any of the following criteria were fulfilled: (1) History of spontaneous pain (2) teeth with clinical signs of either chronic irreversible pulpitis or pulp necrosis such as gingival swelling or sinus tract/purulence or mild pathological mobility, (3) continuous bleeding after amputation of coronal pulp, and (4) physiologic or pathologic external root resorption limited to apical third and with at least two-thirds root intact., Nonrestorable teeth, exhibiting greater than Grade I mobility, demonstrating extensive external/internal resorption were excluded. A total of 60 samples were selected and randomly allocated (30 teeth each) into endoflas (study) group and ZOE (control) group through lottery method. Radiographic appearances of the root and supportive structure were graded into four categories: (a) No pathology (P1), (b) discontinuity of lamina dura (P2), (c) furcation involvement less than or equal to half of the shortest root in vertical measurement (P3), and (d) furcation involving more than half of the shortest root (P4).
Ethical clearance was obtained from the Institutional Review Board. Prior informed consent was taken from all parents/legal guardians of participating children.
Pulpectomy procedure for all teeth was performed by the single operator under stringent aseptic conditions. Under rubberdam isolation and local anesthesia, access to pulp chamber was obtained. Pulp extirpation was done using barbed broaches and working length was determined with conventional radiographic technique. Chemicomechanical preparation was done using Kerr files up to 30 size aided with 3% NaOCl followed by copious saline irrigation., The root canal system was dried with sterile absorbent paper points. The root canals were filled with either endoflas or ZOE and the tooth was sealed temporarily with reinforced zinc oxide eugenol cement. The postoperative radiographs were taken immediately to evaluate obturation level for underfil, optimalfil, and overfil.
The root fillings were categorized with regard to extent in relation to the radiographic apex. Groups of length determination were 0–2 mm (optimal fill), shorter than 2 mm from the radiographic apex (underfil), and overfilled. A tooth was considered to be overfilled even if other roots were filled short or adequate. Similarly, the tooth was categorized as underfill even if remaining roots were adequately filled.
Permanent restoration was done either with stainless steel crown or composite restoration based on esthetic concern of the patient. The present study was a double-blinded, prospective study where the patient and the outcome assessors were not aware about the material used for obturation. The pulpectomized teeth were evaluated clinically and radiographically at 3, 6, 9, 12, and 24 months by two calibrated examiners. The kappa values for inter-examiner and intra-examiner reliabilities were 0.83 and 0.95, respectively.
On each visit, the pulpectomy procedure considered to be clinically successful when tooth is asymptomatic (i.e., without pain, tenderness, abscess, and decrease or absence of mobility) and radiographically considered as successful in the case of a reduction in the size of interradicular radiolucency or the size remaining same and also when no signs of internal or external pathological root resorption demonstrated. If the tooth was symptomatic, it was considered as clinical failure and increase in postoperative inter-radicular radiolucency or development of new postoperative radiolucency was considered as a radiographic failure., By the end of 2 years, 19 children with 25 teeth were available in the study group (endoflas) and 17 children with 27 teeth were available in control group (ZOE). The obtained proportional values were tabulated and compared using Chi-square test. Statistical significance was computed and P ≤ 0.05 was considered statistically significant.
| Results|| |
Preoperative and postoperative signs and symptoms in each group were tabulated and compared [Table 1]. Preoperatively, majority of the teeth presented with pain, tenderness, and also with periradicular pathology in both groups.
|Table 1: Intergroup comparison of clinical and radiographic parameters between zinc oxide eugenol and endoflas groups preoperatively and postoperatively at different follow-up intervals|
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Postoperative clinical findings
At 3-month follow-up, all the teeth (100%) showed clinical success in both endoflas and ZOE groups. By the end of 1 year, two teeth in endoflas group showed pain, tenderness on percussion, and Grade I mobility and were indicated for extraction, whereas three teeth in ZOE group with tender on percussion with gingival erythema and were kept under observation even though considered as failure.
By the end of 2 years, seven teeth in ZOE group and eight teeth in endoflas group showed signs of periradicular infection. Overall, there are decreased number of teeth with pain, tenderness, and periapical rarefaction, but there was increase in the teeth with abscess/sinus and pathological mobility after 2 years.
Postoperative radiographic findings
Immediate postoperative radiographic assessment revealed greater number of overfillings in both the groups [Table 2]. After 2 years of evaluation, there was overall decrease in the periradicular infection in both groups. Statistically, there was no significant difference between the two groups (P > 0.05) at each evaluation. Only 12% of teeth filled with endoflas showed mild deviation in the path of eruption compared to ZOE-treated teeth (26%).
|Table 2: Comparison of fate of periradicular tissues in pulpectomized molars at 2-year follow-up between zinc oxide eugenol and endoflas group|
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Critical appraisal of obstacles beyond apex
Presence of preoperative periapical pathosis
Teeth without any periradicular infection showed high success rate, whereas the presence of periapical pathosis has drastically reduced the success rate in both groups by the end of 2 years [Table 3].
|Table 3: Effect of preoperative periradicular pathosis on success outcome at 2 years follow-up|
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Effect of overfills
Optimal filled teeth in endoflas group and underfilled teeth in ZOE group showed better prognosis than overfills. Overfilled teeth showed decreased success rate in both groups [Table 4].
|Table 4: Comparison of pulpectomy success outcome between zinc oxide eugenol and Endoflas group with respect to extent of fill|
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Fate of over extruded material
The present study evinced the retention of extruded ZOE particles in 92.3% cases at the end of 24-month evaluation [Table 5] and [Figure 1]. In contrast, endoflas-filled teeth did not show any retained particles extraradicularly. Teeth overfilled with endoflas had shown extraradicular resorption within 6–11 months' duration [Table 5] and [Figure 2].
|Table 5: Comparison of the duration taken for the resorption of the excess material|
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|Figure 1: Retained overextruded zinc oxide eugenol particles even at 2-year follow-up|
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The resorption of the filling material in endoflas was in same pace with that of physiological root resorption in 88% teeth. In ZOE group, 63% teeth showed resorption pattern at slower pace [Table 6].
|Table 6: Comparison of postoperative relative resorption of filling material with respect to root resorption at 24 months in zinc oxide eugenol group and endoflas group|
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Success rate at 12- and 24-month follow-up
Teeth filled with endoflas yielded a clinical success of 92% after 1 year compared to ZOE filled teeth (89%). The clinical success of both materials did not differ significantly (P > 0.05) at 12-month follow-up. Seventy-four percent of clinical success was reported in teeth filled with ZOE as compared to endoflas filled teeth (68%) at 2-year follow up. On radiographic evaluation, endoflas-filled teeth demonstrated 56% success, whereas ZOE-filled teeth showed 52% success by the end of the study. Statistically, no significant difference was observed between the groups either clinically (P = 0.629) or radiographically (0.797) [Table 7] and [Figure 3], [Figure 4].
|Table 7: Overall success rate of pulpectomized teeth at 3, 6, 9, 12, and 24 months in both zinc oxide eugenol and endoflas groups|
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|Figure 3: A successful case of zinc oxide eugenol: (a) Immediate postoperative (b) follow-up after 2 years|
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|Figure 4: A successful case of endoflas: (a) Immediate postoperative (b) follow-up after 2 years|
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| Discussion|| |
Bizarre and tortuous root canals cause anatomical hindrance for the complete debridement by mechanical instrumentation resulting in increased resident microflora in the primary teeth. Hence, the success of the pulpectomy in infected primary tooth require antimicrobially effective filling material against resistant microflora and to provide impervious hermetic seal. Endoflas, with its high pH, ensures potential antibacterial effects that reduce periapical inflammatory processes and stimulate periapical healing with increased alkaline phospatase action., It was highly effective against a resistant endodontic pathogen, Enterococcus faecalis. Hence, endoflas has added advantage for the management of infected primary molars.
The present study revealed high success rate with endoflas (92% clinical success and 72% radiographic success) compared to ZOE (89% clinical success and 63% radiographic success). These observations are in accordance with the investigations of the past decade. Ramar and Mungara  has clinically and radiographically evaluated for 9 months and reported that endoflas gave an overall success rate of 95.1% compared to metapex – 90.5% and RC fill – 84.7%. Rewal  observed 100% success with endoflas over ZOE (84%) at 9-month follow-up.
The clinical success rate of endoflas observed was 68% at 24-month evaluation. This success rate was comparatively lower than the reports of Fuks et al. study in 2002 (70%) and Moskovitz et al. study in 2005 (79%). The clinical success of ZOE (74%) was comparatively higher than endoflas with statistically no significant difference between them. ZOE success rate reported in the present study can be correlate with those described by Gould (68.7%), Holan and Fuks (65%) for the management of necrotic teeth with ZOE.
The disparity of success rate could be due to the influence of various factors. According to Reddy VV and Fernandes (1996), variation in the failures may be due to the individual body resistance. Holan and Fuks study  evince that success differences may be related to the pathologic condition of the tooth before treatment rather than to the filling technique per se. The prognosis was better if the tooth was devoid of periapical pathology in the present study (ZOE - 100% success, endoflas – 87.5%). Coll and Sadrian  demonstrated that severe preexisting infection has less chance to be resolved by the pulpectomy procedure Similarly, teeth with preexisting pathology resulted in low success rate as shown in [Table 3].
The extrusion of filling material through the apical foramen was an issue of concern in pediatric endodontics. The current finding revealed overfills in high frequency than underfills and optimal fills. Fuks et al. in their study had similar observations and stated that the preexisting periradicular pathology could be the probable reason for overfillings, as the pathological resorption of the bone and root apex might have facilitated the penetration of the paste.
Optimal fill in endoflas group revealed high success (83.3%) compared to underfill (67%) and the results are in contrast with Moskovitz et al. study  in 2005 (underfill – 91.2%; flush fill – 85%; and overfills – 76.3%). The combined optimal fills and underfills of endoflas showed greater clinical success rate (73.3%) than overfill (60%). These results accord with a Fuks et al. study  in 2002 (overfills – 58%, combined flush and underfills – 83%). Well-known hollow tube effect concept,, in the endodontic lexicon can justify the low success rate of underfill.
The results have proven that endoflas resorption pattern limited to excess extruded beyond apex providing intact hermetic seal. This could be due to fixation effects of chlorophenol on giant cells indirectly responsible for the absorption of extruded material. Mittal et al. observed degradation of the endoflas in subcutaneous tissue after 1 month. The time taken for the resorption of inadvertently extruded endoflas has varied between 20 days and 11months' period in the current study.
Five teeth with preoperative pathology overwhelmed with endoflas overfill showed accelerated root resorption. The reasons behind this consequence might be (1) persistent periradicular infection may induce the formation of odontoclasts, resulting in external root resorption, and this depends on the intensity and continuity of the stimuli and (2) the severe inflammatory reaction with endoflas due to the presence of either eugenol or iodoform or parachlorophenol causes irritation to the periradicular tissues., Bolan and Rocha  reported that chlorophenol also has fixation effect on osteoblast cells thus impairs repair mechanism. Moskovitz et al. reported that endoflas as root canal filling material accelerates root resorption in root canal-treated primary molars due to irritation of the periradicular tissues.
More specifically, accelerated root resorption was observed in two endoflas overfilled teeth involving dental follicle which lead to complete root resorption by the end of 1 year [Figure 5]. Coser et al. reported that when endoflas extruded into dental follicle. It irritates the dental follicle and causes intense inflammatory reaction which further result in accelerated root resorption. In contrast, ZOE overfill involving dental follicle did not present gross changes in the periradicular tissues till the last follow-up [Figure 6].
|Figure 5: Postoperative intraoral periapical radiographs of tooth filled with endoflas: (a) Immediate (b) 6-month follow-up and (c) 1-year follow-up – complete root resorption|
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|Figure 6: Postoperative radiovisiography of tooth overfilled with zinc oxide eugenol: (a) Immediate (b) 1-year 3-month follow-up (c) 2-year follow-up|
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The enigmatic aftermath of endoflas extrusion has resulted in 32% failure considering chlorophenol as main cause of failure. Al-Ostwani et al. used chlorophenol free (CF) endoflas and reported 87.5% clinical success at 12-month follow-up which is comparatively less than the present results (92%), that is, with chlorophenol containing endoflas. He also reported intracanal depletion of endoflas-CF, thus resulting in hollow tube effect. Hence, endoflas with chlorophenol could be a better choice over endoflas-CF for obturation of primary molars.
After 2-years follow-up, the present study revealed no significant difference between endoflas and ZOE for treating infected primary molar. Furthermore, it has proved the ability of endoflas to retain the infected primary molars in functionally stable state. Its resorbable nature limited to extraradicular region provided perfect impervious seal of the root canal system, thus overcoming the drawback of ZOE.
| Conclusions|| |
Considering the superior properties, endoflas could be a potential alternative to ZOE for the obturation of infected primary molars, though it is needed to forestall the drawbacks of chlorophenol when the material goes beyond the canal.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]
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