Biomedical subjects
Publications and source records attributed to J L Gutmann.
The cause, incidence, and prevention of trauma to teeth are highlighted from a contemporary aspect. Causative factors have become more diverse, and the incidence of trauma has become almost equal in both sexes. Newer areas identified include domestic violence, enhanced sporting activities, and an increase in adverse societal manifestations. Prevention, with a focus on education and awareness of diverse populations, is discussed.
A case of severe mucogingival argyria secondary to leakage around and corrosion of silver cone root canal obturations and apical amalgam restorations is presented. Following removal of the silver points and re-treatment of the root canals, periradicular surgery was performed to remove the amalgam root-end restorations and reduce the amount of dispersed metallic particles in the subcutaneous tissues. Subsequent free gingival grafting created an esthetically pleasing and biologically acceptable result.
The success of nonsurgical endodontic treatment is influenced significantly by accurate working-length determination. A variety of guidelines and techniques are available to clinicians in mastering working-length analysis with routine success achieved when multiple methods are used. This article stresses a cognitive, problem-solving approach in the management of clinical variations in working-length determination and interpretation.
Differential radiographic criteria are unreliable for the histological diagnosis of periradicular lesions of pulpal origin. It should not, therefore, be assumed that large lesions or lesions with an opaque border are cystic. Even if cystic, or if strands of epithelium are present, the literature supports repair following the removal of the source of the pathosis. In most cases, the aetiological factors are oral contamination through the root canal or degenerating pulpal tissue. Therefore, the mere surgical removal of lesions of pulpal origin without removing the causes through proper root canal cleaning, shaping and obturation, will not result in the healing of the periradicular tissues. In addition to removing effectively the causative factors, environmental changes in the periradicular tissues caused by the process of canal debridement may inherently aid in the demise of epithelium, when present. The salient issues are discussed in light of thorough debridement of the root canal system, coupled with postulated mechanisms for the resolution of lesions displaying epithelial stands or cavities. Likewise, the role of calcium hydroxide and its potential role in the alteration of the periradicular environment is addressed, with support for the repair of large periradicular lesions without surgical intervention.
Preparations of apical cavities in resected root ends using rotary burs, with and without citric acid rinse, and ultrasonic tips were compared based on the presence or absence of superficial debris and smear layer. Three groups of 20 extracted teeth each were prepared as follows; I, a size 010 round bur was used to prepare an apical cavity 2-3 mm down the long axis of the root; II, treatment as per group I followed by a 60-s rinse with a solution of 10:3 (10% citric acid, 3% Fe2Cl3); and III, an ultrasonic retrotip was used to prepare a 2-3 mm deep apical cavity. Roots were grooved longitudinally, split and prepared for SEM analysis at x100 and x780 magnification. Examiners were calibrated to a standardized grading system. Extensive statistical analyses indicated statistically significant differences within and among the groups (P < 0.05). Root-end preparation with a bur created a heavy smear layer at all levels of the preparation. This layer was partially removed during ultrasonic preparation in the apical two-thirds. A greater removal of the smear layer was achieved with the citric acid rinse (P < 0.05). Coronally, root-end preparations were contaminated with moderate to heavy amounts of debris with all techniques.
The effect of three methods of root-end preparation, following apical resection, on the apical seal of root-end fillings, was studied in vitro. Root canals of 116 single-rooted teeth with mature apices were prepared chemomechanically and obturated with gutta-percha and sealer. The root ends were resected with a diamond bur under water coolant and were prepared as follows: group I a size 010 round bur was used to prepare an apical cavity 2-3 mm down the long axis of the root; group II treatment as per group 1 followed by a 60-s rinse with a solution of 10:3 (10% citric acid: 3% Fe2Cl3); and group III an ultrasonic retrotip was used to prepare a 2-3 mm deep apical cavity. The root end was restored with an EBA cement. Apical leakage was determined using India ink after 7 days and 7 months. The teeth were demineralized, rendered transparent and linear dye penetration was recorded. Results showed that there was no significant difference in leakage between the groups at each time interval (P > 0.05) but there was increased leakage after 7 months (P < 0.01). Cracking of the root surface was seen most often with the ultrasonically prepared roots (P < 0.001).
Following extraction of a symptomatic mandibular premolar which had been subjected to two periradicular surgical procedures, significant apical healing was identified histologically. The implications of these findings are discussed in relation to contemporary advocated treatment regimens, case assessment, and interpretation for success and failure.
The treatment of fractured teeth poses significant problems for the practitioner. However, once the treatment planning decision has been made to attempt to retain the tooth, various practical regimens are available to effect this goal. This paper addresses the specific use of glass ionomer in the restorative management of incompletely, vertically fractured molar teeth integrated with specific root canal treatment techniques.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
A survey was conducted to determine the frequency and popularity of contemporary methods used in endodontic retreatment to remove intraradicular posts. Opinions and rationales were also sought for the choice of surgical management instead of nonsurgical retreatment. A questionnaire was sent to 571 active Diplomates of the American Board of Endodontics with 324 members responding (56.7%). Hand instruments, such as hemostats or special forceps, were the most commonly used, often in conjunction with ultrasonic or sonic vibration to loosen the post or break down the cement interface. A wide range of rationales was identified for the use of surgical retreatment methods, with failure to remove the post after reasonable nonsurgical efforts being the most often cited.
The adaptation of thermoplasticized, injected gutta-percha to prepared dentine devoid of smear layer was examined with SEM. Findings indicate a penetration of gutta-percha into the patient dentinal tubules with or without root canal sealer. The clinical implications of these findings are discussed.
Careful management of the resected root end during endodontic surgery is critical to the overall success of the case. After resection, the root structure presents with multiple anatomical variations and considerations at both a macroscopic and microscopic level. These include root outline, canal anatomy, dentinal tubule configuration, presence of a smear layer and root canal filling material. Proper assessment of these variables will dictate the best methods for root-end management, along with the attainment of an anatomically compatible root face for optimal healing of the periradicular tissues.
The short- and long-term apical seal of root canals obturated with softened alpha-phase gutta-percha on plastic core-carriers, Thermafil, was compared to that of laterally condensed, cold gutta-percha. Fifty-one roots from mandibular molars with separate canals, patent canal orifices and curvatures greater than 15 degrees were cleaned and shaped with K-files and 2.5% sodium hypochlorite to a size 30 at the apex, and flared with Hedstrom files to create a continuously tapering funnel preparation. Canals were randomly obturated with Sealapex root canal sealer and either alpha-phase gutta-percha on a plastic Thermafil carrier, or standard beta-phase gutta-percha with lateral condensation. Teeth were separated into three groups of 17 each and placed in black India ink for 24 h, 7 days or after 5 months storage in water. The teeth were demineralized, rendered transparent, and apical microleakage determined by the linear measurement of dye penetration. Significant differences in microleakage were noted between the 24 h and 5-month Thermafil groups (P < 0.05), 24-h and 7-day lateral condensation groups (P < 0.05), and 24-h and 5-month lateral condensation groups (P < 0.05). There were no significant differences between the two techniques at each time interval. It was concluded that both techniques demonstrated a significant increase in apical microleakage over a 5-month period.
The attainment of profound local anesthesia in the management of pulpal and periradicular pain often eludes even the most skilled clinician; various reasons for this include, but are not limited to, localized inflammation, osseous and neural variations, and poor technique of the operator. This paper reviews these potential impediments while focusing on recognizing occurrences, understanding mechanisms, and applying clinical techniques to effectively eliminate their impact on dental pain management.
Successful management of root structures and soft tissue pathology during endodontic surgical procedures is predicated on achieving both profound anesthesia and effective tissue hemostasis. The degree of anesthesia and hemostasis required depends on the type of endodontic surgical procedure; the more complex and definitive procedures require the greatest extent of vascular control. Predictable methods for achieving successful tissue management are based on the proper use of a vasopressor drug, proper technique and rate of injection, and the use of multiple injection sites. These approaches are designed not only to enhance patient comfort but also to improve visual and manipulative access to the surgical site.
This study was conducted to evaluate the surface effects of the air-powder polisher on direct restorative materials in vivo. Hybrid composite, microfilled composite, amalgam, and glass ionomer restorations were polished for 10 seconds. Replicas of the pre-treatment and post-treatment surfaces were examined in the SEM. A visual and written rating scale was developed to evaluate surface roughness, i.e., 1 = smoothest and 7 = roughest. Micrographs (x200) of the pre- and post-treatment surfaces were evaluated as (1) randomly ordered samples and (2) paired samples. The pre-treatment ratings from the randomly ordered samples ranged from 1-7 for the microfilled and hybrid composite, and 3-7 for the glass ionomer restorations. The range of post-treatment ratings was slightly higher for the hybrid and amalgam (2-7) and the glass ionomer (4-7). Results were analyzed by the Wilcoxon ranks test, which showed that the differences between the ratings of pre and post-treatment surfaces were not significant (P < or = 0.05). A comparison between the two evaluation methods using the Spearman rank correlation (Rho) test showed a good correlation (P < or = 0.05) between the random versus paired evaluation methods and suggested that the random rating method was reliable. Thus, a 10-second exposure with the air-powder polisher does not significantly roughen the surface of the materials tested. Visual observations showed that surface changes were dependent on initial conditions, with smooth surfaces becoming rougher, and surfaces that were extremely rough generally becoming smoother.(ABSTRACT TRUNCATED AT 250 WORDS)
Adaptation and placement of alpha-phase gutta-percha delivered with a plastic core-carrier, Thermafil, was compared to the lateral condensation of gutta-percha in a specific tooth model. Fifty-one mandibular molar roots with separate canals, patent canal orifices and curvatures greater than 15 degrees were cleaned and shaped with K-files and 2.5% sodium hypochlorite to a size 30 at the apex, and flared with Hedstrom files to create a continuously tapering funnel preparation. Canals were randomly obturated with Sealapex root canal sealer and either alpha-phase gutta-percha on a plastic Thermafil carrier, or standard beta-phase gutta-percha with lateral condensation. Roots were radiographed from the proximal and evaluated by three examiners, based on established criteria for overall material adaptation, apical adaptation, and filling material extrusion. Thermafil provided a statistically significant better overall canal obturation (P < 0.001), while, in the apical third, both techniques were not significantly different (P > 0.05). When the apical orifice was patent there was a significant propensity for the extrusion of filling materials beyond the apex (P < 0.001) with the Thermafil technique.