Periodontal ligament injection in the dog primary dentition: spread of local anaesthetic solution

Abstract

Summary. The spread of local anaesthetic solution administered with a pressure syringe has not been studied as extensively in young animals having primary or mixed dentitions as in adult animals. The purpose of this investigation was to study the distribution of local anaesthetic solution injected into the periodontal ligament of young dogs. India ink was added to carpules containing 2% lidocaine and 1:100,000 epinephrine, and the spread of solution was examined macroscopically and microscopically. Injections were made with a pressure syringe (Ligmaject) at 58 sites mesial and distal to primary teeth in five dogs aged 3–9 months. Three dogs were killed within 12 hours, the other two after 5 days. Spread of the ink was studied in non‐decalcified slabs, in three‐dimensional cleared specimens, and in histological sections. The solution usually reached the alveolar bone crest, seeped under the periosteum and alongside vascular channels into bone marrow, reaching natural cavities such as the crypts of tooth buds and the mandibular canal. The ink did not penetrate into the enamel organ or contact the permanent tooth buds. The solution appeared to spread along the path of least resistance, governed by the intricacies of anatomical structures and fascial planes. Therefore the risk of mechanical damage to permanent tooth germs appears to be minimal. Résumé. La diffusion de solutions d' anesthésiques locaux, injectées à l'aide d'une seringue sous pression dans les dentitions primaires ou mixtes de jeunes animaux n' a pas été étudiée de façon extensive comme celà a été fait chez les animaux adultes. Le propos de cette recherche est l'étude de la distribution des solutions d' anesthésiques locaux injectées dans le ligament parodontal de jeunes chiens. De l'encre de Chine a été ajoutée aux carpules contenant de la lidocaïne à 2% et de l'épinéphrine à 1/100,000 et la diffusion de la solution a été etudée macroscopiquement et microscopiquement. Les injections ont été faites par seringue sous pression (Ligmaject) dans 58 sites mésiaux distaux de dents temporaires de cinq chiens âgés de trois à neuf mois. Trois chiens ont été sacrifiés au bout de 12 heures, les deux autres aprés 5 jours. La diffusion de l'encre a été étudée dans des coupes non‐déminéralisées, dans des specimens à trois dimensions et dans des coupes histologiques. La solution atteignait habituellement la crête osseuse alvéolairs, s'infiltrait sous le périoste et le long des trajets vasculaires dans la moelle osseuse, atteignant les cavités naturelles comme le sac des follicules dentaires et la canal mandibulaire. l'encre ne pénétrait pas dans l'émail et n'était pas en contact avec les follicules des dents permenentes. La solution diffusait le long des trajets de moindre résistance, dans les dédales des structures anatomiques et des plans faciaux. Ainsi le risque de traumatisme mécanique des germes des dents permanentes apparait comme minime. Zusammenfassung. Bei einem Versuch mit einem Jungtier mit erster oder gemischten Dentition wurde die Diffusion eines Lokala...

Histopathologic investigation of the effects of prostaglandin E2 administered by different methods on tooth movement and bone metabolism

“…In particular, these cell populations were substantially higher in the submucosal and intraligamentous PGE2 groups than in the intravenous PGE2 and control groups, a result that also agrees with previous findings 13,14,22. The more substantial increase in the cell populations in the intraligamentous PGE2 group may be attributable to both the increased PGE2 concentration in the PDL21,29 and the diffusion of the intraligamentally applied solution within the PDL,26 from where it passes subperiosteally at the level of the alveolar crest and proceeds along the vascular canals to reach and act directly on the bone marrow.…”

“…Lidocaine might reduce the pain caused by the injection of PGE2, itself a pain mediator. The consensus in dentistry is that intraligamentous application of an active substance through a pressurized syringe is reliable and safe 25,26. The American Dental Association Council on Dental Materials, Instruments, and Equipment characterized intraligamentous injection as being "an effective method, sufficient for pulpal anesthesia in dental operations.…”

“…"25 Clinical studies have shown efficiencies of intraligamentous injection ranging from 81% to 98% 25. Although studies of its effects on the surrounding tissues have indicated that local tissue injury may occur,26 histologic examination has yielded little evidence of tissue injury and indicated reversible damage when injury occurs 27. Roahen and Marshall25 studied the effects of intraligamentous injection of 2% lidocaine containing 1:100,000 epinephrine on the pulp and periodontal tissues of the dog.…”

“…They reported pulpal inflammation and external resorption foci on the root surface, both of which were reversible and most of which were no longer visible after 30 days. Further, Tagger et al26 examined tooth movement following intraligamentous injection of a solution either with (1:100,000 epinephrine in 2% lidocaine and China ink) or without (3% mepivacaine and China ink) a vasoconstrictor in 12 dogs. They reported good penetration of China ink into the PDL and roots, with no apparent anatomic barriers, in both groups.…”

Distribution of Lidocaine in Alveolar Tissues in Rabbits

“…There were few studies that reported the tissue distribution of local anesthetic after regional injection into oral tissue. Tissue specimens of dogs were observed 15 minutes, 12 hours, and 5 days after administration of a mixture of 2% lidocaine containing 1:100,000 epinephrine and India ink, injected into the periodontal ligament space 14,15) . However, these studies did not investigate the tissue distribution of local anesthetics shortly after regional injection.…”