Divisions of the maxilla.

The palatal mucosa and maxillary nerve were removed from the areas of A (I) and B (J). The maxilla was divided into 6 parts along the solid line (–). The asterisk shows the site of injection. The broken line (---) shows the position of the frontal section for the ¹⁴C-autoradiogram.

A: right palatal mucosa.

B: left palatal mucosa.

C: right maxillary part (including right molars; the zygomatic arch was removed).

D: left maxillary part (including left molars; the zygomatic arch was removed).

E: right incisive part (including the right incisor).

F: left incisive part (including the left incisor).

G: right palatal part.

H: left palatal part.

I: right maxillary nerve.

J: left maxillary nerve.

Distribution and concentration of lidocaine in the maxilla.

After 20 µl of 2% ¹⁴C-lidocaine was injected into the right palatal mucosa proximal to the first molar of the rat with (•) and without (○) 10 µg/ml adrenaline, the radioactivity in (A) right palatal mucosa, (B) left palatal mucosa, (C) right maxillary part, (D) left maxillary part, (E) right incisive part, (F) left incisive part, (G) right palatal part, (H) left palatal part, (I) right maxillary nerve, and (J) left maxillary nerve was measured with a liquid scintillation counter. Concentration (ng/mg wet weight) of lidocaine was calculated from the specific radioactivity.

Data are mean ± SD (n  =  5), * p<0.05 vs plain lidocaine.

Autoradiogram of ¹⁴C-lidocaine in the frontal section of the maxilla.

Twenty µl of 2% ¹⁴C-lidocaine was infiltrated into the right palatal mucosa proximal to the first molar with (the right side) and without (the left side) 10 µg/ml adrenaline. The maxilla removed 2, 20, 40, and 60 min after the injection was frozen and the 20-µm frontal section was sliced at the injection point with a cryostat microtome. The section was exposed for 40 days at −80°C to BioMax XAR-film® (Kodak, USA). The section stained with 0.25% eosin was laid on the autoradiogram of XAR-film, which was scanned by a scanner with transmitted light. Red triangles in the autoradiogram show the middle of the left and right ethmoidal sinuses. When plain ¹⁴C-lidocaine was injected (the left side), ¹⁴C-lidocaine diffused into the area including the palatal mucosa on both sides, hard palate, maxilla, maxillary nerve, and bottom of the ethmoidal sinuses 2 min after the injection. ¹⁴C-Lidocaine remained only in the palatal mucosa and hard palate of the injection site 60 min after the injection. When ¹⁴C-lidocaine with adrenaline was injected (the right side), ¹⁴C-lidocaine widely infiltrated into the area from both sides of the palatal mucosa to the middle of the ethmoidal sinuses 2 min after the injection. Greater vertical infusion was observed than when plain ¹⁴C-lidocaine was injected. ¹⁴C-lidocaine remained only in the area around the injection site at 60 min, the same as when plain ¹⁴C-lidocaine was injected.

Quantitative analysis of ¹⁴C-autoradio-gram.

¹⁴C-Lidocaine was infiltrated into the palatal mucosa with (•) and without (○) 10 µg/ml adrenaline. The frontal section was prepared in the same way as described in Fig. 3. The section was exposed to the imaging plate for 40 days at room temperature. Quantitative analysis of ¹⁴C-autoradiogram in the plate was performed by an image analyzer. The amount of autoradiographic signal in the section sliced 2 min after the injection of plain lidocaine was expressed as 100 (592 ± 7 dpm/section) in the graph. The amounts of radiographic signal in the lidocaine with adrenaline group at 2 min (1.8 times), 20 min (2.1 times) and 40 min (1.7 times) were significantly more than those in the plain lidocaine group.

Data are mean ± SD (n  =  5), * p<0.05 vs plain lidocaine.

Concentrations of radioactivity derived from ¹⁴C-lidocaine in the serum.

After 20 µl of 2% ¹⁴C-lidocaine with (•) and without (○) 10 µg/ml adrenaline was injected into the right palatal mucosa proximal to the first molar, the radioactive concentration (dpm/ml) in the serum was measured with a liquid scintillation counter. The serum lidocaine concentration after the injection of lidocaine with adrenaline was significantly lower from 2 to 50 minutes and higher after 60 minutes than that when injected alone.

Data are mean ± SD (n  =  7), * p<0.05 plain lidocaine vs lidocaine with adrenaline.

Chromatogram of radioactive metabolites derived from ¹⁴C-lidocaine in (A) the maxillary tissue and (B) the serum.

Two percent ¹⁴C-lidocaine with (▪) and without (□) 10 µg/ml adrenaline was injected into the right palatal mucosa proximal to the first molar. Radioactive substances, which were extracted from the maxillary tissue (palatal mucosa and maxillary part) and the serum taken 60 min after the injection, were separated by thin layer chromatography (TLC). The TLC plate was Silicagel 60F₂₅₄® (Merck, Germany). The area between the lower end of the plate and the solvent front was divided into nine zones. A spot of lidocaine on the plate was confirmed with UV lamp (253.7 nm). Authentic lidocaine was detected in zone No. 4. Lidocaine or the metabolite in each silica gel zone was scratched from the plate and ¹⁴C radioactivity in the zone was measured with the liquid scintillation counter. The radioactivity in each zone as a percentage of the total radioactivity on the TLC plate was calculated. (A) More than 70% of the total radioactivity in the tissue existed in the original lidocaine zone (No. 4) in either case. (B) More than 70% of the total radioactivity in the serum existed in the original lidocaine zone in either case.

Data are mean ± SD (n  =  4).

Effect of lidocaine on blood flow rate in upper lip of rats.

After 20 µl of 0.9% NaCl (⧫), 2% lidocaine (○), 10 µg/ml adrenaline (▵), and lidocaine with 10 µg/ml adrenaline (•) was injected to the left upper lip, the blood flow rate of the lip was measured by laser Doppler flowmetry. No significant change of blood flow rate was found in the 0.9% NaCl group (control) from 10 to 60 min after the injection (repeated measures of ANOVA and Student-Newman-Keuls test). Two percent lidocaine significantly increased the blood flow rate compared with the control from 15 min to 55 min after the injection. Lidocaine with adrenaline significantly decreased the blood flow rate compared with the control from 10 min to 45 min after the injection.

Data are mean ± SD (n  =  4), † p<0.05, 2% lidocaine vs control, * p<0.05, 2% lidocaine with 10 µg/ml adrenaline vs control.

Medical emergencies classified by gender and age (n  =  205).

There were more female cases than male cases. Their ages ranged between 2 years old and 84 years old.

Diagnosis of complications (n  =  205).

Most of the medical emergency cases were accidental ingestion.

The second-most common was vasovagal reflex.

Places where medical emergencies occurred (n  =  205).

Outpatient clinics of conservative dentistry and oral surgery were the two main sources of medical emergency cases. Others included on the campus (3%) and outpatient clinic of oral implant (3%), radiology (2%), ward (1%), general reception (1%) and unknown (1%).

Situations when medical emergencies occurred (n  =  205).

About two thirds of medical emergency cases occurred during dental treatment.

Situations when medical emergencies occurred in which local anesthesia was used (n  =  52).

More than half of emergency cases occurred during dental treatment.

Emergency flowchart for accidental ingestion or pulmonary aspiration This system was introduced in 2003. Dental anesthesiologists manage these cases.

Facial asymmetry in a patient with fibrous dysplasia.

Preoperative chest X-ray image.

Arrows show hypertrophy and ground glass appearance of the costal bones; these findings are consistent with fibrous dysplasia.

Preoperative cranial computed tomographic (CT) images and magnetic resonance image (MRI).

Hypertrophy and ground glass appearance with secondary narrowing of the maxillary sinus and nasal cavity of the left side of the skull bones are observed in the horizontal (a) and sagittal (b) planes of CT images of the patient with fibrous dysplasia.

Three-dimensional CT image shows facial asymmetry (c). Axial T2-weighted sagittal MRI indicates as sclerotic expansile fibrous dysplasia lesioninvolving the left maxillary sinus, adjacent maxilla, mandible, sphenoid bone, frontal bone and occipital bone (d).

The time courses of EDT after mandibular nerve injury with tooth extraction.

##p<0.01 vs control #p<0.05 vs control.

*p<0.01 Group S vs Group NS.

All data are drawn with mean ± SD. Student's t-test was adopted for comparing the two groups at each evaluation time. The paired t-test was used for comparing the control value with the evaluation value in each group. Group S showed better recovery than Group NS. The injured trigeminal nerve in Group S had completely recovered at PTP1M.

The impressions of patients about recovery from mandibular nerve injury.

*p<0.01 Group S vs Group NS.

The Numeric Rating Scale was divided into four stages of not cured (0), slightly cured (1), almost cured (2) and cured (3). The Mann-Whitney test was used to compare the two groups at each evaluation time. Group S recognized recovery significantly at each evaluation time compared with Group NS.