Restoration of a vertical tooth fracture and a badly mutilated tooth using canal projection.

Indian J Dent Res. 2007 Apr-Jun;18(2):87-9

Authors: Velmurugan N, Bhargavi N, Lakshmi N, Kandaswamy D

Management of vertically fractured tooth or a perforation frequently poses problem during endodontic management. Such teeth often need a pre-endodontic restoration prior to initiation of root canal therapy to aid in the placement of rubber dam clamp. This paper describes a simple method of placement of a pre-endodontic restoration using the canal projection technique using hollow metallic needles as sleeves.

PMID: 17502715 [PubMed - indexed for MEDLINE]

Evaluation of working length determination methods: an in vivo / ex vivo study.

Indian J Dent Res. 2007 Apr-Jun;18(2):60-2

Authors: Shanmugaraj M, Nivedha R, Mathan R, Balagopal S

This comparative study was done to determine the accuracy in measuring the working length of root canal using tactile method, electronic apex locator and radiographic method, in vivo and comparing the lengths so measured to the actual working length, ex vivo, after extraction. Thirty single-rooted teeth scheduled for extraction were selected for the study. After obtaining the consent from patients, a preoperative radiograph was taken and access opening was done. Working length was determined by tactile method, by using Ingle's radiographic method and by using a Foramatron-IV digital apex locator. The teeth were then extracted and the actual working length was determined by placing an endodontic file in the root canal 0.5 mm short of the apex. The results indicated that among the three methods, the electronic apex locator showed the highest accuracy and the highest reliability for working length determination.

PMID: 17502709 [PubMed - indexed for MEDLINE]

A comparative SEM investigation of the smear layer following preparation of root canals using nickel titanium rotary and hand instruments.

J Oral Sci. 2007 Mar;49(1):47-52

Authors: Zand V, Bidar M, Ghaziani P, Rahimi S, Shahi S

The aim of this study was to compare the efficacy of NiTi flex K-file instruments and rotary FlexMaster and Race instruments (short for reamers with Alternating Cutting Edges) in root canal preparation. A total of 75 single rooted teeth with minimum curvature (< 5 degrees ) were selected and divided into three groups, each containing 25 teeth. Canals were prepared with NiTi flex K-file, FlexMaster and Race instruments using crown down preparation technique, up to size #40. After each instrument, the root canals were flushed with 5 ml of 0.5% NaOCl solution. The amount of debris and smear layer was quantified on the basis of Hulsmann method using a scanning electron microscope. Completely cleaned root canals were not found after instrumentation with any of the three instruments. In general, FlexMaster instruments left significantly less debris and smear layer than Race and NiTi flex K-file instruments (P < 0.05). NiTi flex K-files resulted in significantly more smear layer (P < 0.05) compared to Race and FlexMaster instruments only in the apical third of the canal. (J. Oral Sci. 49, 47-52, 2007).

PMID: 17429182 [PubMed - in process]

An in vitro comparative study of apically extruded debris resulting from conventional and three rotary (Profile, Race, FlexMaster) instrumentation techniques.

J Oral Sci. 2006 Jun;48(2):85-8

Authors: Zarrabi MH, Bidar M, Jafarzadeh H

Canal preparation is one of the most important stages of endodontic therapy, and various techniques have been applied for it. The present study was conducted to compare the quantity of debris extruded from the apical foramen during canal preparation during the manual technique and with the use of three rotary systems (Profile, Race, FlexMaster). One hundred single-rooted premolars were divided into four groups of 25 teeth each. For collection of debris, vials containing distilled water and weighed before canal preparation were used. Groups H, P, R and F were prepared by the manual step-back technique, and with the use of the Profile system, Race system and FlexMaster system, respectively. After canal preparation, the vials were dried thoroughly and reweighed. The difference between the weights of the vials at the two stages was taken as the debris weight. The mean debris weights were compared by one-way ANOVA. Group H had the highest mean debris weight, which was significantly different from those of the rotary groups (P < 0.001). The lowest mean debris weight was related to group R, which was significantly different from that of group F but not significantly different from that of group P. It was concluded that the Race system induces less extruded debris than the manual technique and the FlexMaster system.

PMID: 16858137 [PubMed - indexed for MEDLINE]

Endodontic therapy.

J Am Dent Assoc. 2006 Jun;137(6):722, 724; author reply 724, 726

Authors: Kolzet DJ

PMID: 16803799 [PubMed - indexed for MEDLINE]

Endodontic management of taurodontic teeth.

Indian J Dent Res. 2005 Oct-Dec;16(4):177-81

Authors: Prakash R, Vishnu C, Suma B, Velmurugan N, Kandaswamy D

Taurodontism is a morpho-anatomical change in the shape of the tooth in which the body of the tooth is enlarged and the roots are reduced in size. Although taurodontism is a dental rarity, this unusual radicular form should merit circumspect considerations in planning and treatment. Endodontic management in taurodont teeth has been described as complex and difficult. The present paper describes the successful completion of endodontic treatment in three taurodontic teeth with appropriate use of instruments and techniques and also emphasizes the need for post endodontic rehabilitation.

PMID: 16761713 [PubMed - indexed for MEDLINE]

The importance of apical patency and cleaning of the apical foramen on root canal preparation.

Braz Dent J. 2006;17(1):6-9

Authors: Souza RA

The apical limit of root canal instrumentation has always been a matter of great controversy. Despite the large number of published studies on this subject, a consensus has not yet been reached. In fact, the recent discussion on apical patency and cleaning of the apical foramen, as well as the incorporation of these procedures to the endodontic treatment, seem to have raised even more polemics. It is likely that all this polemics has its roots in the lack of interrelation between the theoretical knowledge of pulp stump and periapical tissues and the real clinical practice. By addressing the most important aspects of this theme, this paper aims to present news concepts about the importance of apical patency and cleaning of the apical foramen during root canal preparation.

PMID: 16721456 [PubMed - indexed for MEDLINE]

[Root canal therapy of resinified teeth with surgical operating microscope and ultrasonic instruments]

Shanghai Kou Qiang Yi Xue. 2006 Apr;15(2):117-20

Authors: Xu Q, Lin JQ, Mai S, Liu JW

PURPOSE: To evaluate the role of surgical operating microscope and ultrasonic instruments in endodontic treatment of patients who underwent previous resinifying therapy. METHODS: 63 premolars and molars that had been treated with resinifying therapy before were selected for root canal therapy. The coronal portion of resinified root canals were negotiated with ultrasonic instruments under surgical operating microscope, and the apical portion was managed with small size hand files and 15% EDTA. The root canals of all cases were shaped by Nickel-Titanium rotary instruments Hero 642, and obturated with lateral condensation technique. The negotiation of root canal system, instrument fracture, alterations of canal morphology, and operation time were recorded. The efficiency of preparation and obturation was analyzed by radiographs before and after treatment. RESULTS: The root canals of 54 teeth were negotiated, enlarged and obturated, with a success rate of 85.7%. No complications were found, such as vertical fracture, ledge, perforation and instrument separation. Good result of treatment was achieved in the 54 cases. CONCLUSIONS: The use of surgical operating microscope and ultrasonic instruments is proved to be effective in negotiation of coronal portion of the resinified root canals. Nevertheless, the use of ultrasonic instruments in apical or curved portion of root canals is not encouraged.

PMID: 16685346 [PubMed - in process]

[Nonsurgical micro-endodontics and its outcome]

Shanghai Kou Qiang Yi Xue. 2006 Feb;15(1):1-6

Authors: Ling JQ, Wei X

The introduction of dental operating microscope and microscopic instruments including ultrasonic tips has revealed the endodontic therapy. Dental operating microscope provides magnification and illumination for the operational area. Cases which should be treated by surgical approach in the past can be managed predictably by nonsurgical micro-endodontics. The use of dental operating microscope and ultrasonics in non-surgical endodontics includes location of missed canal, removal of intracanal post and separated instruments, negotiation of ledged canals, management of apical transportation and perforation repair.

PMID: 16525598 [PubMed - in process]

Evaluation of the smear layer removal effectiveness of EDTA using two techniques: an SEM study.

J Contemp Dent Pract. 2006 Feb 15;7(1):9-16

Authors: Tinaz AC, Karadag LS, Ala&#xE7;am T, Mihçioglu T

Obtaining the cleanest canal possible before obturation is one of the goals of endodontic treatment. The purpose of this study was to compare the smear layer removal capability of ethylenediamine tetra-acetic acid (EDTA) application with passive ultrasonic and cotton wrapped on reamer activation. Twelve extracted human teeth with single root canals were used for the study. They were conventionally hand instrumented using reamers and K files. The apical aspect of the canals was enlarged to a #40 file. The teeth were divided into 4 four groups, instrumented and irrigated as follows: Group-A EDTA agitated at the end of preparation with cotton wrapped on a reamer for 1 min; Group-B EDTA applied with ultrasonic agitation for 1 min; Group-C irrigated with EDTA+sodium hypochlorite (NaOCl) (negative control group); and Group-D irrigated with distilled water (positive control group). After scanning electron microscopic study at three different levels, smear layer and dentinal tubules were scored. Means were tested for significance using the Z test. When the techniques were compared, the cotton wrapped on reamer agitation method was as successful as the ultrasonic activation of the files. Although all groups had significantly higher smear layer scores at apical compared to coronal sections, no significant differences were recorded.

PMID: 16491143 [PubMed - indexed for MEDLINE]

Inability of laser and rotary instrumentation to eliminate root canal infection.

J Am Dent Assoc. 2006 Jan;137(1):67-70

Authors: Jha D, Guerrero A, Ngo T, Helfer A, Hasselgren G

BACKGROUND: The authors evaluated the antibacterial effectiveness of laser instrumentation and rotary instrumentation of anterior, single-rooted teeth infected with Enterococcus faecalis. METHODS: The authors divided 35 infected samples into five groups: Group A: inoculation, laser, 17 percent ethylene-diamine-tetra-acetate (EDTA), 2.5 percent sodium hypochlorite (NaOCl) (n=10); Group B: inoculation, laser, 17 percent EDTA, sterile saline (n = 10); Group C: inoculation, rotary, 17 percent EDTA, 2.5 percent NaOCl (n=10); Group D: inoculation, no instrumentation (positive control) (n=5); Group E: no inoculation, no instrumentation (negative control) (n=5). They sampled and incubated dentin shavings from each canal for bacterial growth. RESULTS: In Group A, eight tubes were positive for bacterial growth. In Group B, 10 tubes were positive for bacterial growth. In Group C, six tube were positive for bacterial growth. In Group D, all of the tubes were positive for bacterial growth. In Group E, no tubes showed bacterial growth. The Fisher exact test showed no significant differences among groups A, E and C. CONCLUSION: Neither the laser nor the rotary instrumentation was able to eliminate endodontic infection. CLINICAL IMPLICATIONS: Although lasers have been presented as high-tech tools for disinfecting root canals, the laser was ineffective in this study.

PMID: 16457001 [PubMed - indexed for MEDLINE]

How to kill a tooth.

J Am Dent Assoc. 2005 Dec;136(12):1711-3

Authors: Christensen GJ

Many dentists report increased activity in endodontic therapy. Although retention of teeth through most of life by many patients and the aging population are potential reasons for this increase, it is possible that some of the new dental procedures, instruments or materials that have become popular in recent years also are significant causative factors. Several potential preventable reasons for increased pulpal death and the resultant need for endodontic therapy are discussed in this article.

PMID: 16383054 [PubMed - indexed for MEDLINE]

A radiographic study of the relationship between technical quality of coronoradicular posts and periapical status in a Jordanian population.

J Oral Sci. 2005 Sep;47(3):123-8

Authors: Jamani KD, Aqrabawi J, Fayyad MA

A radiographic study was conducted to investigate the relationship between the technical quality of coronoradicular posts and periapical status. A total of 400 periapical radiographs, including 560 posts, of patients attending the Dental Department at Jordan University Hospital were scanned and studied. It was found that maxillary teeth were more frequently restored with posts (65.36%) than mandibular teeth (34.64%). Tapered posts accounted for 73.93% of the posts used. The ratio of the mean post length to crown length was 0.8, and that to root length was 0.45. The mean length of the remaining gutta percha apical to the end of the post was 6.22 mm. In addition, 25% of the posts deviated from the line of the root canal. Periapical radiolucency was evident in 53.93% of the assessed teeth. It is concluded that inadequate root canal treatment and coronoradicular posts are associated with increased prevalence of periapical radiolucency, and that general dental practitioners should be better trained in performing endodontic treatment and restoring endodontically treated teeth.

PMID: 16313089 [PubMed - indexed for MEDLINE]

Fiber optic fluorescence microprobe for endodontic diagnosis.

J Dent Educ. 2005 Jun;69(6):633-8

Authors: Sarkissian A, Le AN

Successful endodontic therapy requires total debridement as well as complete obturation of the root canal to the cemento-dentinal junction. The goal of this study was to investigate the feasibility of using quantitative fluorescence spectroscopy for the detection and localization of pathological dentin, pulpal remnants, and microorganisms within the root canal. Specific aims were to identify: 1) characteristic excitation/emission spectra for healthy dentin, decayed dentin, enamel, and pulp; 2) the potential of specific spectral data for differentiating between these tissues; and 3) the potential of spectral data for detecting the presence and identifying four common endodontic pathogens. Fluorescence spectra were determined in the tissues of permanent human teeth, extirpated healthy and necrotic pulps, and four endodontic pathogens. Excitation/emission spectra were collected at 366 nm, 405 nm, and 440 nm excitation. Marked differences in spectral signatures between the different tissues under investigation were observed. We postulate that the differences in fluorescence spectra of decayed vs. healthy dentin are due to the loss of mineralized tissue components and increased organic presence and water in these tissues. Pulpal tissue showed distinctly different fluorescence spectra from healthy and decayed dentin, providing a basis for differentiating between tissue categories. Each bacterial species demonstrated distinct spectral emission patterns.

PMID: 15947209 [PubMed - indexed for MEDLINE]

Effect of cryogenic treatment on nickel-titanium endodontic instruments.

Int Endod J. 2005 Jun;38(6):364-71

Authors: Kim JW, Griggs JA, Regan JD, Ellis RA, Cai Z

AIM: To investigate the effects of cryogenic treatment on nickel-titanium endodontic instruments. The null hypothesis was that cryogenic treatment would result in no changes in composition, microhardness or cutting efficiency of nickel-titanium instruments. METHODOLOGY: Microhardness was measured on 30 nickel-titanium K-files (ISO size 25) using a Vicker's indenter. Elemental composition was measured on two instruments using X-ray spectroscopy. A nickel-titanium bulk specimen was analysed for crystalline phase composition using X-ray diffraction. Half of the specimens to be used for each analysis were subjected to a cryogenic treatment in liquid nitrogen (-196 degrees C) for either 3 s (microhardness specimens) or 10 min (other specimens). Cutting efficiency was assessed by recording operator choice using 80 nickel-titanium rotary instruments (ProFile 20, .06) half of which had been cryogenically treated and had been distributed amongst 14 clinicians. After conditioning by preparing four corresponding canals, each pair of instruments were evaluated for cutting efficiency by a clinician during preparation of one canal system in vitro. A Student's t-test was used to analyse the microhardness data, and a binomial test was used to analyse the observer choice data. Composition data were analysed qualitatively. RESULTS: Cryogenically treated specimens had a significantly higher microhardness than the controls (P < 0.001; beta > 0.999). Observers showed a preference for cryogenically treated instruments (61%), but this was not significant (P = 0.21). Both treated and control specimens were composed of 56% Ni, 44% Ti, 0% N (by weight) with a majority in the austenite phase. CONCLUSIONS: Cryogenic treatment resulted in increased microhardness, but this increase was not detected clinically. There was no measurable change in elemental or crystalline phase composition.

PMID: 15910471 [PubMed - indexed for MEDLINE]

Do procedural errors cause endodontic treatment failure?

J Am Dent Assoc. 2005 Feb;136(2):187-93; quiz 231

Authors: Lin LM, Rosenberg PA, Lin J

BACKGROUND: This article reviews the effect of endodontic procedural errors, such as underfilling, overfilling, root perforations and separated instruments, on the outcome of endodontic therapy. TYPES OF STUDIES REVIEWED: Filling the root canal more than 2 millimeters from the radiographic apex (underfilling) or beyond the radiographic apex (overfilling), perforations of the root canal system and instrument separation are possible complications of endodontic therapy. Although these procedural errors may have different causes, they all may affect the outcome of treatment. RESULTS: Endodontic procedural errors are not the direct cause of treatment failure; rather, the presence of pathogens in the incompletely treated or untreated root canal system is the primary cause of periradicular pathosis. Procedural errors typically are due to several factors. Among them is a lack of understanding of the root canal anatomy, the principles of mechanical instrumentation and tissue wound healing. CLINICAL IMPLICATIONS: Procedural errors impede endodontic therapy, thus increasing the risk of treatment failure, especially in teeth with necrotic pulps and periradicular lesions. However, procedural errors often are preventable.

PMID: 15782522 [PubMed - indexed for MEDLINE]

A modified hemostat for endodontic instruments.

J Am Dent Assoc. 2005 Jan;136(1):80

Authors: Zuckerman GR

PMID: 15693501 [PubMed - indexed for MEDLINE]

Survey of attitudes, materials and methods employed in endodontic treatment by general dental practitioners in North Jordan.

BMC Oral Health. 2004 Sep 10;4(1):1

Authors: Al-Omari WM

BACKGROUND: General dental practitioners provide the majority of endodontic treatment in Jordan. The aim of this study was to gather information on the methods, materials and attitudes employed in root canal treatment by dentists in North Jordan, in order to evaluate and improve the quality of current practice. METHODS: A questionnaire was posted to all registered general dental practitioners working in private practice in Irbid Governate in North Jordan (n = 181). The questionnaire included information on methods, materials and techniques used in endodontic treatment. RESULTS: Reply rate was 72% (n = 131). The results demonstrated that only five dentists used rubber dam occasionally and not routinely. The majority used cotton rolls for isolation solely or in combination with a high volume saliva ejector (n = 116). The most widely used irrigants were sodium hypochlorite and hydrogen peroxide, which were used by 32.9% (n = 43) and 33.6% (n = 44) of the respondents, respectively. Forty eight percent of the respondents (n = 61) used the cold lateral condensation technique for canal obturation, 31.3% (n = 41) used single cone, 9.9% (n = 13) used vertical condensation and 12.2% (n = 16) used paste or cement only for the obturation. The majority used zinc oxide eugenol as a sealer (72.5%). All, but one, respondents used hand instruments for canal preparation and the technique of choice was step back (52.7%). More than 50% (n = 70) of the dentists took one radiograph for determining the working length, whilst 22.9% (n = 30) did not take any radiograph at all. Most practitioners performed treatment in three visits for teeth with two or more root canals, and in two visits for teeth with a single root canal. CONCLUSIONS: This study indicates that dentists practicing in North Jordan do not comply with international quality standards and do not use recently introduced techniques. Many clinicians never take a radiograph for determining the working length and never used rubber dam or intra-canal medicaments.

PMID: 15361258 [PubMed - as supplied by publisher]

The impact of post space preparation with Gates-Glidden drills on residual dentin thickness in distal roots of mandibular molars.

J Am Dent Assoc. 2004 Jul;135(7):903-9

Authors: Kuttler S, McLean A, Dorn S, Fischzang A

BACKGROUND: Posts frequently are used to retain buildups. The authors examined the effects of post space preparation with Gates-Glidden drills on residual dentin thickness in distal roots of mandibular molars. METHODS: The authors embedded 26 root-treated mandibular molars in endodontic cubes and sectioned them perpendicularly to their long axis at 1.8-millimeter intervals. They placed Gates-Glidden drills nos. 3, 4, 5 and 6 sequentially to 5 mm short of working length in the distal canals. After using each drill size, the authors measured the dentin thickness from light microscopic images of the tooth slices. RESULTS: The authors analyzed data to detect changes resulting from canal instrumentation. They performed statistical analysis by partitioning the variability in a nested analysis of variance. Strip perforations occurred with a no. 4 Gates-Glidden drill 7.3 percent of the time and more frequently with larger drills. After endodontic treatment alone, the canal wall on the furcal side was less than 1 mm thick 82 percent of the time and less than 0.5 mm thick 17.5 percent of the time. CONCLUSIONS: Dentin thickness correlates inversely to post space diameter. A no. 4 Gates-Glidden drill caused strip perforations in 7.3 percent of the canals studied, and therefore the authors recommend that Gates-Glidden drills larger than a no. 3 not be used in these roots. After endodontic treatment, the furcation-side dentin thickness was less than 1 mm in 82 percent of the teeth. CLINICAL IMPLICATIONS: Post space preparation in mandibular molars carries significant risk of perforation. Post space in such teeth should be limited to the endodontically prepared canal.

PMID: 15354901 [PubMed - indexed for MEDLINE]

Inferior alveolar nerve paresthesia relieved by microscopic endodontic treatment.

Bull Tokyo Dent Coll. 2003 Nov;44(4):209-12

Authors: Yatsuhashi T, Nakagawa K, Matsumoto M, Kasahara M, Igarashi T, Ichinohe T, Kaneko Y

We experienced two cases of inferior alveolar nerve paresthesia caused by root canal medicaments, which were successfully relieved by microscopic endodontic treatment. In the first case, the paresthesia might have been attributable to infiltration of calcium hydroxide into the mandibular canal through the root canals of the mandibular left second molar tooth. In the second case, the paresthesia might have been attributable to infiltration of paraformaldehyde through the root canals of the mandibular right second molar tooth. The paresthesia was relieved in both cases by repetitive microscopic endodontic irrigation using physiological saline solution in combination with oral vitamin B12 and adenosine triphosphate.

PMID: 15103918 [PubMed - indexed for MEDLINE]

[A study of the shape of prepared canal of commonly used hand endodontic instruments]

Shanghai Kou Qiang Yi Xue. 1998 Mar;7(1):37-9

Authors: Zhu YQ, Wang XY

OBJECTIVE:Straight or slightly curved single root canals of teeth (<20 degree) were instrumentated with three commonly the hand endodontic instruments,which included K reamer,K file and H filel.The shape of prepared canal and root canal deviation at three levels were measured by computerized digital image processing program.The results demostrated that any significant differences were not found on root canal deviation in either labio-lingual or mesiodistal direction at each level,and that the shape of prepared canal was not different significantly.Apical transportation of the severely curved artificial root canals(25-30 degree) showed that H file was the most severe,K reamer was the least.It is suggested in this article how we select endodontic instruments rationally and effectively.

PMID: 15071700 [PubMed - as supplied by publisher]

[Effect on preparing curved artificial root canal with five handle endodontic instruments II comparision of shaping ability]

Shanghai Kou Qiang Yi Xue. 1998 Dec;7(4):221-3

Authors: Zhu YQ, Xia WW, Wang XY

OBJECTIVE:To compared the shaping ability of five handle endodontic instruments. METHODS: The canal shape of prepared artificial root canals with five handle endodontic instruments were observed by light-microscope. RESULTS: Apical zips,elbows and perforations were not found. Ledges occurred in speciments of K-Flex group and they were relating to resinous plugs.The apical transportatins were relating to resinous plugs.The apical transportations of K-Flex group and H file group are much greater than other groups. CONCLUSION: Unifile or K file is first choice to prepare curved artificial root canals with routine preparation technique by comprehensive evaluaion of the cutting ability and shaping ability of five handle endodontic instruments.

PMID: 15071632 [PubMed - as supplied by publisher]

[Effect on preparing curved artificial root cancals with five handle endodonic instruments I.comparison of cutting ability]

Shanghai Kou Qiang Yi Xue. 1998 Dec;7(4):219-20

Authors: Zhu YQ, Wang B, Wang XY

OBJECTIVE: To compare the cutting ability of five handle endodontic instruments. METHODS: The speciments weight loss following serial preparation of artificial root canal were measured with electronic analysis balance. RESULTS: The greatest cutting ability occurred with H file,then with K-flex file,Unifile,K file and K reamer. CONCLUSION: The cutting ability of endodontic instrument is influenced by several factors,such as metallurgical properties,cross-sectional configuration of shaft,flute design and tip design.

PMID: 15071631 [PubMed - as supplied by publisher]

Vertical root fractures: clinical and radiographic diagnosis.

J Am Dent Assoc. 2003 Apr;134(4):434-41

Authors: Cohen S, Blanco L, Berman L

BACKGROUND: Early detection and management of vertical root fractures, or VRFs, remain a vexing issue that has caused needless suffering for patients as well as for dentists. The authors present techniques to aid the dentist in recognizing VRFs. METHODS: During a five-year period, the authors examined 36 patients who had VRFs. Absent control subjects and a larger number of patients, the authors did not design this investigation for statistical analysis. They diagnosed VRFs through dental histories and clinical and radiographic examinations. RESULTS: The study revealed VRFs in 36 teeth, two of which were vital and 34 of which were nonvital (that is, endodontically treated). The 34 VRFs resulted from excessive operative procedures performed in the root canal after endodontic therapy. Thirty-one of these 34 VRFs were caused by poorly designed dowels (too long, too wide or both) or inappropriate selection of the tooth as a bridge abutment; two VRFs were caused by a restoration that exerted lateral pressure on the axial walls of the preparation; and one VRF was caused by overzealous endodontic forces. The VRFs in the two vital teeth were in men who had a history of bruxism or clenching. CONCLUSIONS AND CLINICAL IMPLICATIONS: VRFs can be detected early by listening to the patient's chief complaints, carefully examining periapical and bitewing radiographs and performing a thorough clinical examination.

PMID: 12733776 [PubMed - indexed for MEDLINE]

Cervical shaping in curved root canals: comparison of the efficiency of two endodontic instruments.

Pesqui Odontol Bras. 2002 Oct-Dec;16(4):327-31

Authors: Busquim SS, dos Santos M

The aim of this study was to determine the removal of dentin produced by number 25 (0.08) Flare files (Quantec Flare Series, Analytic Endodontics, Glendora, California, USA) and number 1 e 2 Gates-Glidden burs (Dentsply - Maillefer, Ballaigues, Switzerland), in the mesio-buccal and mesio-lingual root canals, respectively, of extracted human permanent inferior molars, by means of measuring the width of dentinal walls prior and after instrumentation. The obtained values were compared. Due to the multiple analyses of data, a nonparametric test was used, and the Kruskal-Wallis test was chosen. There was no significant difference between the instruments as to the removal of dentin in the 1st and 2nd millimeters. However, when comparing the performances of the instruments in the 3rd millimeter, Flare files promoted a greater removal than Gates-Glidden drills (p > 0.05). The analysis revealed no significant differences as to mesial wear, which demonstrates the similar behavior of both instruments. Gates-Glidden drills produced an expressive mesial detour in the 2nd and 3rd millimeters, which was detected trough a statistically significant difference in the wear of this region (p > 0.05). There was no statistically significant difference between mesial and lateral wear when Flare instruments were employed.

PMID: 12612771 [PubMed - indexed for MEDLINE]

Endodontic perforation repair with resin-ionomer: a case report.

J Contemp Dent Pract. 2000 Nov 15;1(4):48-59

Authors: Breault LG, Fowler EB, Primack PD

Root perforations are significant complications of endodontic treatment. However, when teeth are of strategic value, perforation repair is clearly indicated. The successful utilization and placement of a subgingival resin-ionomer restoration to repair an endodontic root perforation is demonstrated. Sustained tissue health and minimal probing depths at the surgical site demonstrate clinical success.

PMID: 12167950 [PubMed - indexed for MEDLINE]

Evaluation of a digital measurement tool to estimate working length in endodontics.

J Contemp Dent Pract. 2001 Feb 15;2(1):24-30

Authors: Lamus F, Katz JO, Glaros AG

The purpose of the study was to compare the segmental measurement tool from the Shick Technologies CDR digital system with the conventional film radiography measurement technique to determine preoperative working length. Natural extracted human teeth with varying degrees of root curvature were used. All teeth were imaged using the Shick Technologies CDR direct digital system and conventional E-speed film. Measurements from digital radiography and conventional film were compared with measurements made directly from the endodontic files. The Wilks' Lambda multivariate test was used. The mean measurement of each modality was compared with the other and with the gold standard. The test showed statistically significant differences between the two modalities at p<0.05. The mean measurements for both modalities were not significantly different from the gold standard. The modality most closely approaching the gold standard was the conventional film.

PMID: 12167941 [PubMed - indexed for MEDLINE]

Using a Hedstr&#xF6;m endodontic file to retrieve a root tip.

J Am Dent Assoc. 2002 Apr;133(4):473

Authors: Stoner KE

PMID: 11991465 [PubMed - indexed for MEDLINE]

Periapical surgery of 29 teeth. A comparison of conventional technique, microsaw and ultrasound.

Med Oral. 2002 Jan-Feb;7(1):46-9, 50-3

Authors: Vallecillo Capilla M, Muñoz Soto E, Reyes Botella C, Prados Sáchez E, Olmedo Gaya MV

OBJECTIVES: A clinical and radiological study is made of the results obtained with different periapical surgical techniques. MATERIAL AND METHODS: Twenty-nine single-root teeth from 29 patients with periapical pathology following correct endodontic treatment were divided into three groups: (A) 10 patients in which rotary instruments were used to perform osteotomy, apicoectomy and cavity preparation; (B) 10 patients in which rotary instruments were used to perform osteotomy and apical resection, with ultrasound root-end cavity preparation; and (C) 9 patients in which microsaws were used for osteotomy, and ultrasound for cavity preparation. All teeth were filled with IRM. Clinical and radiological controls were made after 10 days, one and 6 months, and one year. RESULTS: Clinical success with the absence of symptoms was achieved in 17 cases (58.6%), while in 16 patients (55.2%) the X-ray images showed complete bony regeneration (complete healing). The clinical success rate after one year was 40%, 70% and 66.7% in groups A, B and C, respectively, while complete radiographic healing was recorded in 30%, 60% and 77.8%. There were three failures in group A, two in group C, and none in group B. CONCLUSION: In conclusion, the best results were obtained when ultrasound was used for root-end cavity preparation.

PMID: 11788808 [PubMed - indexed for MEDLINE]

21st-century endodontics.

J Am Dent Assoc. 2000 Jun;131 Suppl:39S-46S

Authors: Glickman GN, Koch KA

BACKGROUND: Endodontics as a discipline has offered patients the opportunity to maintain their natural teeth. As the population expands and ages, the demand for endodontic therapy can be expected to increase as patients seek dental options to keep their teeth for a lifetime. CLINICAL IMPLICATIONS: New materials, techniques and instruments are entering the market-place to assist dentists in providing patients with more predictable and reliable endodontic treatment. In addition, these new systems make the delivery of endodontic services more efficient. This article describes these advances in endodontic treatment for dentists interested in incorporating these advances into their clinical practice.

PMID: 10860344 [PubMed - indexed for MEDLINE]

Bronchoscopic removal of foreign bodies in adults: experience with 62 patients from 1974-1998.

Eur Respir J. 1999 Oct;14(4):792-5

Authors: Debeljak A, Sorli J, Music E, Kecelj P

The authors reviewed their experience with therapeutic bronchoscopy for removal of tracheobronchial foreign bodies in the adult. Bronchoscopy records and collection of foreign bodies in the endoscopic department were retrospectively examined. Among 37,466 bronchoscopies performed between 1974-1998, 62 (0.2%) were performed for the removal of tracheobronchial foreign bodies. Medical history was suggestive of foreign body aspiration in 33 patients and the chest radiograph was suggestive in 10 patients. The procedure was performed with the flexible bronchoscope in 42 patients (68%), rigid bronchoscope in 4 (6%), and with both in 16 (26%) patients. Foreign bodies were found in the right bronchial tree on 42 occasions, in the left on 20 and in the trachea once. In 39 patients, inflammatory granulations were found around the foreign body. The origins of the foreign bodies included: bone fragments (n=31), vegetable (n=10), broncholith (n=8), a part of dental prosthesis (n=7), endodontic needle (n=2), a metallic (n=2), or plastic (n=1) particle, a tracheostomy tube (n=1) and a match (n=1). In one patient, 2 foreign bodies were found. The foreign bodies were successfully removed in all but 2 patients (3%). The most useful instruments for removal were alligator forceps and the wire basket. Foreign bodies in the tracheobronchial system are rare in adults. They can be successfully removed in the majority of patients under either flexible or rigid bronchoscopy.

PMID: 10573222 [PubMed - indexed for MEDLINE]

Using a copper band to isolate severely broken teeth before endodontic procedures.

J Am Dent Assoc. 1999 Jul;130(7):1095

Authors: Linden R

PMID: 10422405 [PubMed - indexed for MEDLINE]

A simplified approach to isolating a single tooth before endodontic therapy.

J Am Dent Assoc. 1999 Jun;130(6):846-7

Authors: Estafan DJ, Harris B, Estafan A

PMID: 10377643 [PubMed - indexed for MEDLINE]

Forceps extraction of teeth with severe internal root resorption.

J Am Dent Assoc. 1997 Jun;128(6):751-4

Authors: Javaheri DS, Garibaldi JA

Many treatment plans require a dental practitioner to maintain the entire labial cortical plate of bone when removing an anterior maxillary tooth. A tooth with an undermined root secondary to an endodontic perforation or internal (Idiopathic) resorption can present a surgical challenge to the general practitioner. This article describes a new technique for extracting a severely undermined anterior maxillary tooth while maintaining the entire labial cortex of bone.

PMID: 9188233 [PubMed - indexed for MEDLINE]

Current trends in endodontic treatment: report of a national survey.

J Am Dent Assoc. 1996 Sep;127(9):1333-41

Authors: Whitten BH, Gardiner DL, Jeansonne BG, Lemon RR

The authors surveyed 360 general dentists and 291 endodontists to obtain information on routine, nonemergency endodontic treatments adapted to clinical practice. Frequent practices and recent advances in treatment modalities-including instrumentation, obturation, intracanal preparations, medications and restorations-are highlighted.

PMID: 8854609 [PubMed - indexed for MEDLINE]

Statistical models for evaluating the penetrating ability of endodontic instruments.

J Dent Res. 1990 Sep;69(9):1617-21

Authors: Fuchs C, Friedlander C, Rosenberg E, Tamse A

An in vitro study was conducted to evaluate the penetrating ability of hand instruments (No. 10 K-file and "Pathfinder") and an automated device with a No. 08 (Canal Finder System) file in 270 extracted curved and narrow molar roots. The roots were randomly allocated to six groups, each one corresponding to a different permutation of the three instruments. The experiment was performed in three sequential stages, and Stages II and III were undertaken only in roots where no apical penetration was achieved in the previous stage(s). Statistical models were designed to fit the resulting clinical data. The No. 08 Canal Finder System and No. 10 K-file proved to be similar in their penetrating ability in Stage I (with estimated probabilities of 71.1% and 68.8%, respectively). The No. 08 Canal Finder was found to be the most efficient in Stage II and especially in Stage III, with a probability of penetration of 20.7%, compared with 9.8% for the "Pathfinder" and 7.4% for the No. 10 K-file.

PMID: 2398189 [PubMed - indexed for MEDLINE]

Stiffness of endodontically-treated teeth related to restoration technique.

J Dent Res. 1989 Nov;68(11):1540-4

Authors: Reeh ES, Douglas WH, Messer HH

Endodontically-treated posterior teeth are susceptible to fracture; consequently, full-occlusal-coverage restorations are recommended. We designed this study to examine the potential for alternative restorative techniques for pulpless teeth, using strain gauges mounted on extracted maxillary second premolars to measure strains generated by nondestructive occlusal loading. Cuspal stiffness was evaluated on the following sequentially performed procedures: unaltered tooth, completion of all endodontic procedures, appropriate restorative preparation, and restoration. The restorative procedures evaluated were: (1) amalgam, (2) cast gold onlay, (3) composite restoration with enamel etch, and (4) composite restoration with enamel and dentin etch. Finally, all teeth were loaded to fracture. Cast gold was the strongest restorative material tested (2.11 relative stiffness, compared with that of the unaltered tooth at 1.00), and amalgam was the weakest (0.35 relative stiffness). Composite restoration and enamel plus dentin etch were almost as strong as the unaltered tooth (0.87 relative stiffness), while enamel-etch-only yielded lower stiffness (0.51).

PMID: 2584522 [PubMed - indexed for MEDLINE]

Effects of dental root posts on human gingival fibroblasts in vitro.

J Dent Res. 1980 Mar;59(3):651-6

Authors: Arvidson K, Cottler-Fox M, Friberg U

Dental root posts of gold-plated brass and German silver caused injury of human gingival fibroblasts in vitro. Posts made of stainless steel, titanium and gold alloys showed no discernible effects of cell morphology of apparent metabolic activity during the two-week period of observation.

PMID: 6937497 [PubMed - indexed for MEDLINE]

Efficiency of cold sterilizing agent for endodontic procedure.

J Dent Res. 1979 Feb;58(2):670

Authors: Suchde RV, Talim ST, Billimoria KF

PMID: 105025 [PubMed - indexed for MEDLINE]

Comparison of theoretical and experimental bending and torsional moments of endodontic files and reamers.

J Dent Res. 1967 Sep-Oct;46(5):1058-63

Authors: Craig RG, Mc Ilwain ED, Peyton FA

PMID: 5248970 [PubMed - indexed for MEDLINE]

Periapical temperatures of teeth undergoing endodontic therapy.

J Dent Res. 1966 Sep-Oct;45(5):1424-9

Authors: Selden HS

PMID: 5225314 [PubMed - indexed for MEDLINE]