Paraesthesia--a consequence of a controversial root-filling material? A case report

Anesthesia following overfilling of a root canal sealer into the mandibular canal: A case report

The surgical treatment of a case of anesthesia that occurred with the extrusion of Endomethasone root canal sealer into the mandibular canal is presented. Endomethasone is a neurotoxic root canal sealer containing paraformaldehyde and eugenol. The literature indicates immediate surgical decompression on the extrusion of Endomethasone into the mandibular canal. In our case, the decompression surgery was done 3 weeks after the endodontic mishap. The nearly complete resolution of anesthesia 4 months following the decompression surgery suggests that the neurotoxic effects of Endomethasone are still reversible after 3 weeks.

INFERIOR ALVEOLAR NERVE PARESTHESIA RELIEVED BY MICROSCOPIC ENDODONTIC TREATMENT

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.

Lesions Of The Inferior Alveolar Nerve Arising From Endodontic Treatment

A lesion of the IAN following endodontic treatment of the lower molars and premolars is not a rare event and presents an uncomfortable situation both for the dental surgeon and the patient. Injury can result on the one hand by direct intrusion of the instrument through the apex into the mandibular canal, and on the other by the filling material which becomes forced into the mandibular canal. In the latter case, a nerve lesion will only result when the filling material contains neurotoxic substances such as paraformaldehyde. With a direct lesion or when forcing of resorbable filling material into the mandibular canal is suspected, one should first employ a wait-and-see approach, because usually the only nerve damage is in the form of neuropraxy or axonotmesis for which there is a high rate of spontaneous regeneration. However, if neurotoxic filling material is introduced into the direct vicinity of the nerves, the mandibular canal should be opened and the filling material should be removed as early as possible. If the filling material is forced directly within the endoneurium between the nerve bundles, the damaged nerve sections must be resected and bridged using transplants from the sural or greater auricular nerves.

Mental nerve paresthesia associated with an amalgam filling: a case report

We present a case report in which a mental nerve paresthesia occurred in connection with an amalgam filling placed in direct contact with the pulp of a mandibular first molar. The main evidence for amalgam being the dominant etiological factor was the positive epicutaneous patch testing response to the components of the amalgam alloy, and the total remission of symptoms without further clinical complications after removal of the amalgam filling and subsequent endodontic therapy.

Formaldehyde release from root-canal sealers: influence of method

AIM

To examine formaldehyde release from three different root-canal sealers: one phenol resin, one epoxy resin and one paraformaldehyde containing zinc oxide eugenol cement.

METHODOLOGY

Formaldehyde was measured from freshly mixed material and from specimens allowed to set for 2 days or 2 weeks. Different mixing ratios and sample sizes were tested. Analysis was performed by reacting formaldehyde with acetylacetone and ammonia to form diacetyldihydrolutidine, which was revealed by spectrophotometry.

RESULTS

Analysis revealed that mixing ratio, time after mixing and surface:weight ratios of specimens had different influences on the formaldehyde release from different materials.

CONCLUSIONS

From the results of this study it is difficult to define a standardized in-vitro test that can be applied universally for the definitive determination of formaldehyde release from endodontic sealers. Prediction of in-vivo formaldehyde release from endodontic sealers is difficult.

Comparative neurotoxic effects of root canal filling materials on rat sciatic nerve

The neurotoxic effects of the root canal filling materials--Endomethasone, N2 Universal, Traitement SPAD, Sealapex, and Calciobiotic Root Canal Sealer (CRCS)--were investigated on isolated rat sciatic nerves after local application. All of the canal filling materials reversibly inhibited the compound action potential (cAP) amplitudes. N2 Universal produced a 50% inhibition in 4.2 +/- 0.2 min. Traitement SPAD, Endomethasone, and CRCS produced the same inhibition in 6.4 +/- 0.3, 6.5 +/- 0.2, and 6.6 +/- 1.1 min, and Sealapex in 9.2 +/- 2.0 min. The inhibitory effect of Sealapex decreased fastest, and 43% recovery of cAP amplitude was observed in 60 to 70 min. The inhibitory effects of Endomethasone, CRCS, and N2 Universal were more pronounced, and 10 to 20% recovery in cAP amplitudes were observed in 2 h. The inhibitory effect of Traitement SPAD was more persistent with 4% recovery in 2.5 h.

Temporary paresthesia of the lower lip: a complication of orthodontic treatment. A case report

Temporary mental paresthesia of the lower lip as a result of orthodontic treatment is extremely rare. Only two cases seem to have been reported earlier, a further case is described and discussed. The cause of this uncommon complication in the present case is obviously the close relationship between the distal root of the lower left second permanent molar and the mandibular canal.

Formaldehyde and phenol exposure during an anatomy dissection course: a possible source of IgE-mediated sensitization?

The sensitizing potency of formaldehyde and phenol exposure during 4 weeks of an anatomy dissection course was assessed in 45 medical students. Specific IgE against formaldehyde by RAST and by ELISA and specific IgE against phenol by ELISA were assessed before and after the course. At the start of the course, symptoms, type I allergy, respiratory diseases, and smoking habits were noted. At the end of the course, only symptoms experienced during the dissection lessons were assessed. Indoor formaldehyde levels were measured continuously. The mean indoor formaldehyde level was 0.124 +/- 0.05 ppm, with a minimum of 0.059 ppm and a maximum of 0.219 ppm. Specific IgE against formaldehyde or phenol was found in none of the subjects at the beginning of the course, and no student showed specific IgE against formaldehyde or phenol after the course. Assessment of primarily irritant symptoms during the lesson revealed itch and paraesthesia of hands in 33/45 students (P < 0.00005), headache in 15/45 students, burning eyes in 13/45 students (P < 0.02), dizziness in 8/45 students (P < 0.008), sneezing in 4/45 students, epistaxis in 2/45 students, and shortness of breath in 1/45 students. According to our data, 1-month exposure to formaldehyde and phenol during an anatomy dissection course does not induce specific IgE against formaldehyde or phenol.

Disabling complications following inadvertent overextension of a root canal filling material

A case of pain and paresthesia of the mental nerve following inadvertent introduction of root canal filling material into the inferior alveolar nerve canal is described. The causes and treatments of this disabling complication are discussed.