Intracanal Calcium Hydroxide Research Articles

Effect of calcium hydroxide and chlorhexidine medicaments on the apical seal.

Leakage of the root canal system is an importent consideration when placing an intracanal medicament. The aim of this in vitro study was to compare the effect of calcium hydroxide and 1% chlorhexidine gel as intracanal medicaments on tooth apical seal. Seventy extracted, single-rooted maxillary anterior teeth were divided into the three experimental groups (n=20). All root canals were instrumented with step-back technique and divided into three groups. Group 1 had root canal dressing with calcium hydroxide; group 2 had root canal dressing with 1% chlorhexidine gel and group 3, did not receive a dressing. The roots were incubated in 100% humidity at 37°C for 7 days. After removing the dressings, all canals of the experimental groups were obturated using a cold lateral condensation technique. The root surfaces of all specimens were coated with two layers of nail varnish, except for the 2 mm surrounding the apical foramen. Apical sealing ability was assessed by dye leakage method and the specimens were examined under a stereo-microscope. Dye penetrations were measured and analyzed using ANOVA and post-hoc Tukey test. Calcium hydroxide group had the least frequency of apical leakage at 2 mm level (0.46±0.40 mm), whilst chlorhexidine group showed the greatest apical leakage (0.86±0.42 mm). There was statistical difference between group 1 and 2 (P<0.05), but no statistical difference between group 1 and 3, or between groups 2 and 3 (P>0.05). Intracanal calcium hydroxide medicament may decrease apical leakage of gutta-percha root fillings when AH26 sealer is used; chlorhexidine may increase the leakage.

Non-surgical management of a mutilated maxillary central incisor with open apex and large periapical lesion

A 24-year-old female patient reported with a mutilated maxillary left central incisor. The coronal tooth structure remaining was very less, discolored, and brittle. She gave history of trauma about 15 years back when the tooth got fractured. An intraoral periapical radiograph revealed an open apex and a large periapical lesion. The case was managed successfully by conservative means using intracanal calcium hydroxide and mineral trioxide aggregate (MTA) apical barrier followed by a fiber post and a core. The final crown restored back esthetics and function. A 6-month follow-up demonstrated a clinically asymptomatic and adequately functional tooth, with radiological signs of healing.

Effects of Intracanal Mineral Trioxide Aggregate and Calcium Hydroxide During Four Weeks on pH Changes in Simulated Root Surface Resorption Defects: An In Vitro Study Using Matched Pairs of Human Teeth

Introduction Diffusion of hydroxyl ions from intracanal calcium hydroxide (CH) through dentin is used to arrest external inflammatory root resorption. However, long-term and short-term CH placement has been associated with an increased risk of root fracture. Intracanal mineral trioxide aggregate (MTA) might provide an alternative to CH as a source of hydroxyl ions. This in vitro study compared the effects of intracanal MTA and CH on hydroxyl ion diffusion through dentin by measuring pH changes over time in simulated root surface resorption defects prepared in matched pairs of teeth; the null hypothesis tested was that there is no difference. Methods Root surface cavities were prepared 5 mm from the apex in extracted human permanent anterior teeth (21 matched pairs) and 7 additional teeth (controls). Root canals were instrumented to size 50/.04 and filled with either tooth-colored MTA (ProRoot) or CH (UltraCal XS); control teeth were filled with saline. The pH in root surface cavities was measured at 3 hours, 24 hours, 1 week, 2 weeks, 3 weeks, and 4 weeks. Results In controls, pH readings did not differ significantly during the 4 weeks ( P > .05, repeated-measures analysis of variance [ANOVA]). For the experimental intragroup effects, significant pH changes occurred over time in the MTA group ( P = .005, repeated-measures ANOVA) and the CH group ( P < .0001). For the experimental intergroup effects, the overall mean pH was higher in the MTA group (8.66; standard error [SE], 0.07) compared with the CH group (8.46; SE, 0.07) ( P = .014, paired t test). At 4 weeks pH was higher in the MTA group (8.30; SE, 0.16) compared with the CH group (7.90; SE, 0.11) ( P = .011); at all other time points intergroup differences were insignificant. The null hypothesis was rejected. Conclusions Intracanal MTA and CH groups differed in their overall effect on pH measured in simulated root surface resorption defects. At 4 weeks intracanal placement of MTA compared with CH resulted in a small but significantly higher pH.

Removability of three intracanal calcium hydroxide pastes from the root canal

Removability of three intracanal calcium hydroxide pastes from the root canal

Fracture Resistance of Human Root Dentin Exposed to Intracanal Calcium Hydroxide

Abstract The purpose of the present study was to determine if exposure to intracanal calcium hydroxide [Ca(OH 2)] alters the fracture resistance of human root dentin. One hundred and two freshly extracted single rooted human teeth divided into three groups of 34 teeth each. Coronal access and endodontic instrumentation using round burs, stainless steel files, and Profile GT rotary files were completed for each tooth. The prepared root canal system of each tooth was filled with saline solution (group 1), USP Ca(OH) 2 (group 2), or Metapaste (group 3). The apicies and access openings were sealed with composite resin and the teeth were immersed in saline. After 30 days, the roots of 17 teeth from each group were sectioned horizontally into 1-mm thick disks and each disk was loaded to fracture at 2.5 mm/min with a SATEC universal-testing machine. After 180 days the same procedure was performed on the remaining 17 teeth in each of the 3 groups. The peak load at fracture was measured for each dentin disk. Data were analyzed using one-way ANOVA and a post hoc Student-Newman-Keuls test. After 30 days exposure to the test solution, there was no difference in the peak load at fracture for the three groups of teeth. However, after 180 days, the roots of the teeth exposed to USP Ca(OH) 2 showed a significant decrease in peak load at fracture when compared to the 30-day groups and the 180-day groups exposed to saline or Metapaste.

Bacteria recovered from teeth with apical periodontitis after antimicrobial endodontic treatment

Chávez de Paz LE, Dahlén G, Molander A, Möller A, Bergenholtz G. Bacteria recovered from teeth with apical periodontitis after antimicrobial endodontic treatment. International Endodontic Journal, 36, 500-508, 2003. To determine whether there is a pattern for certain bacteria to remain after chemo-mechanical treatment of root canals in teeth with apical periodontitis. Consecutive root-canal samples of 200 teeth receiving root-canal treatment, referred from general practitioners and endodontic specialists for analyses of cultivable microbes, were studied prospectively. To be included, samples had to be taken at a treatment session subsequent to the one at which endodontic therapy was initiated. All samples were from teeth that either presented with clinical or radiographic evidence of apical periodontitis or both. Bacteriological findings were linked to clinical and radiographic parameters including status of the root canal prior to treatment, namely, vital pulp, necrotic pulp or root filled. A total of 248 strains were isolated from 107 teeth giving bacterial growth. Gram-positives predominated (85%). Lactobacillus spp. (22%), nonmutans streptococci (18%), and Enterococcus spp. (12%) were the most common isolates. Gram-negative anaerobes were relatively sporadic. Large radiographic bone lesions, persistent pain and use of intracanal calcium hydroxide dressing correlated with bacterial presence (P < 0.05). Once established, nonmutans streptococci, enterococci and lactobacilli appear to survive commonly following root-canal treatment of teeth with clinical and radiographical signs of apical periodontitis.

Influence of calcium hydroxide intracanal medication on apical seal.

The aim of this study was to determine the influence of calcium hydroxide intracanal medication and various techniques for its removal on the sealing ability of gutta-percha root fillings with a zinc oxide-eugenol sealer. Eighty extracted mature human mandibular molar roots were divided into three groups of similar root-canal configuration. Calcium hydroxide paste was made by mixing calcium hydroxide powder with distilled water at a powder to liquid ratio of 1:1.25. After root canals were prepared and enlarged to a minimum of size 30 with the Profile 0.06 system, calcium hydroxide paste was placed in the canals of two groups, but no medication was placed in the control group. The intracanal calcium hydroxide was removed with two different techniques, 1 week after medication: K-files one size larger than the master apical file (MAF) were used with 2.5% NaOCl and 15% EDTA solutions in one group, whilst K-files the same size as the MAF were used with 2.5% NaOCl solution in another group. Canals were obturated with gutta-percha and Tubli-Seal cement using the lateral condensation technique. The apical sealing-ability was assessed by dye leakage and cross-sections of the specimens were examined under a stereomicroscope. The dye-penetration level was measured and analyzed using Fisher's exact test and Duncan's multiple range test. The calcium hydroxide-medicated groups showed significantly more dye leakage than the non-medicated control group (P < 0.05). However, there was no significant difference between the two calcium hydroxide-medicated groups (P > 0.05). The stereomicroscopic views showed a relatively uneven and thicker layer of sealer in the calcium hydroxide-medicated groups. Calcium hydroxide intracanal medication may increase apical leakage of gutta-percha root fillings when a zinc oxide-eugenol sealer is used.

Comparative study of surgical fenestration and conventional surgical and non-surgical techniques in the management of large periapical lesions

Surgical Fenestration - a procedure of opening into a patholgical lesion for diagnostic and therapeutic purpose, was compared with conventional apicectomy and conservative endodontic treatment using calcium hydroxide, to assess the efficacy of surgical fenestration in terms of quality and rate of post-surgical healing and total treatment time. 44 cases having peri-apical lesions >2 cm in diameter on radiograph were included in the study. The age of the patient ranged from 15-45 years. The cases were randomly divided into the three study groups : Group I was treated with conservative endodontic treatment using intra-canal calcium hydroxide. Group II was treated by conventional root-canal treatment and apicectomy. Group III cases were treated by root-canal treatment and surgical fenestration. It was found that all the three modalities of treatment were effective in the management of large peri-apical lesions. However, treatment time in group II and III was much shorter (one week - in either single visit or in two visits) compared to group I (2-8 months) requiring multiple visits. Also, it was seen that surgical fenestration was simpler to perform, required less surgical time, was least traumatic with minimal post-surgical complications compared with conventional apicectomy procedure. Quality of post-operative healing was comparable in both the Group II and III cases. Rate of healing in Group III cases at 3 months follow-up was found to be greater in comparison to group II cases, however, at 6 months follow-up, healing in both, group II and III cases was comparable. Another interesting observation of the study was, that all but one of the tissue specimens from group II and group III cases (n-25) were found to be apical cyst (92.3%)

Effect of different endodontic treatment protocols on periodontal repair and root resorption of replanted dog teeth

This study examined, histologically, the healing of intentionally damaged root surfaces of replanted teeth with either uninfected or infected root canals treated with short- and long-term calcium hydroxide. Thirty beagle dog incisors were randomly divided into four groups. In group 1, uninfected obturated incisors were extracted, the roots were longitudinally grooved and the teeth were replanted within 2 min. In group 2 the root canals were artificially infected followed by extraction, longitudinal grooving, and replantation as described in group 1. Fourteen days after replantation, the root canals were fully instrumented and medicated with intracanal calcium hydroxide. One week later the root canals were permanently obturated with gutta-percha and sealer. The teeth in group 3 were treated as described in group 2 but after 1 wk the calcium hydroxide dressing was repacked for the duration of the study. In group 4 (positive control) the teeth were treated as described in groups 2 and 3 but no endodontic treatment was performed. After 8 wk, sacrifice and histological preparation were carried out. In group 1 complete cemental repair was seen in all teeth. In groups 2 and 3, complete and incomplete cemental repair was seen in seven and two teeth, respectively. An ankylotic area was present in one tooth in group 3. None of the teeth in group 4 showed cemental repair. It was concluded that short- and long-term calcium hydroxide treatment resulted in similar healing patterns when endodontic treatment is initiated 14 days after replantation of teeth.

Effect of delayed calcium hydroxide treatment on periodontal healing in contaminated replanted teeth

The effect of delayed intracanal calcium hydroxide treatment on experimentally induced extensive inflammatory root resorption in monkeys was studied. A significant shift from inflammatory resorption to ankylosis was noted following calcium hydroxide treatment. Furthermore, calcium hydroxide treatment appeared to change the pattern of ankylosis over time, although the total ankylotic area remained the same. Ankylosis preceded by root resorption (replacement resorption) increased, while ankylosis not associated with root resorption decreased. It was concluded that intracanal calcium hydroxide treatment of teeth with compromised PDM may cause unnecessary replacement resorption if left in the root canal for a long time or changed repeatedly.

Effect of immediate calcium hydroxide treatment and permanent root‐filling on periodontal healing in contaminated replanted teeth

The effect of immediate permanent root-filling and immediate intracanal calcium hydroxide treatment on experimentally contaminated and necrotized periodontal membranes (PDM) in avulsed and subsequently replanted monkey teeth was studied. Almost the entire root surface in the non-endodontically treated control teeth were covered with inflammatory resorption. A significant shift towards ankylosis not associated with root resorption (greater than 80% of the total root surface area) was noted following calcium hydroxide treatment. About two thirds of the root surfaces from the teeth with permanent root fillings showed surface resorptions or ankylosis preceded by root resorption. The root surface area which would have been covered by inflammatory resorption, unless endodontic treatment had been implemented, were instead predominantly covered by either surface resorption (permanent root filling) or ankylosis (calcium hydroxide treatment). Ankylosis compared with surface resorption may in the long term lead to progressive loss of root substance due to replacement resorption. It was concluded that calcium hydroxide may be an excellent initial intracanal treatment in teeth with healthy PDM, but care should be taken not to risk unnecessary development of ankylosis by prolonged treatment of teeth with compromised PDM.