Effect of extracorporeal shockwave therapy (ESWT) on pulpal blood flow after orthodontic treatment: a randomized clinical trial.

OBJECTIVES: The effect of non-invasive extracorporeal shockwaves on pulpal blood flow in orthodontic patients who have undergone active treatment was investigated. MATERIALS AND METHODS: Seventy-two adult patients were enrolled in the clinical trial and allocated by block randomization to a treatment or a placebo group at a 1:1 ratio. The patients were required to be otherwise healthy. Blinding was performed for the subjects and the outcome assessor. The region of interest was the mandibular incisors and canines, which were vital, unrestored, and had experienced no trauma. The active treatment group received a single shockwave treatment with 1000 impulses at 0.19-0.23 mJ/mm(2) while the placebo group was treated with a deactivated shockwave applicator but acoustic sham. Pulpal blood flow was evaluated four times over a period of 6 months starting from the day of bracket removal, using a laser Doppler device. RESULTS: Thirty patients were evaluated in each group. Orthodontic patients who have undergone active treatment tend to have high levels of pulpal blood flow which decrease over a period of 6 months. Pulpal blood flow did not differ significantly over 6 months between the placebo and treatment group. Shockwave treatment was associated with no significant effect in respect of tooth type, age, sex, or mean blood pressure, and had no unintended pernicious effects. CONCLUSIONS: Extracorporeal shockwaves had no statistically significant effect on pulpal blood flow. Multiple applications of ESWT in a pathological setup may be needed in future studies to demonstrate significant differences. CLINICAL RELEVANCE: The absence of any adverse effects justifies further principal investigations of the use of shockwave treatment in the oral cavity.

Changes in Maxillary Canine Pulpal Blood Flow During Dentoalveolar Distraction Osteogenesis.

OBJECTIVE: The aim of this study was to assess the effects of dentoalveolar distraction osteogenesis (DD) on the pulpal blood flow (PBF) of maxillary canines. MATERIALS AND METHODS: A laser Doppler flowmeter (LDF) was used to measure PBF in maxillary canines of 10 patients undergoing DD (study group) and 10 nonsurgical subjects who received no orthodontic treatment (control group). PBF was measured at baseline, at 4 and 7 days postoperatively, at the end of distraction and at the end of consolidation in the study group and at similar time-points in nonsurgical control subjects. Data were analyzed using paired and Student t tests, with the significance level set at 0.05. RESULTS: Study findings showed that baseline PBF values did not differ significantly between groups. PBF in the control group did not vary over time; however, in the study group, an initial decrease in PBF was observed at 4 days postoperatively and was followed by a gradual increase to preoperative levels at the end of distraction. CONCLUSIONS: During the DD latency period, there appears to be a short-lived ischemic phase when perfusion of pulp tissue declines; however, blood-flow returns to normal by the end of distraction.

Changes in human pulp blood flow during canine retraction.

AIM: To evaluate the effects of maxillary canine retraction on pulpal blood flow (PBF) in humans as recorded by laser Doppler flowmetry (LDF). METHODS: Maxillary canines of 24 participants were divided into two groups (n = 12 each). Teeth in the study group underwent maxillary canine retraction using mini-implants as anchorage for approximately 4 months, with 100 g of force applied via coil springs. Subjects in the control group received no orthodontic treatment. LDF measurements were recorded at baseline (T0); during retraction, at 24 hours (T1), 3 days (T2), 7 days (T3) and 1 month (T4); and at the end of retraction (T5) in the study group and at similar time-points in control subjects. Data were analyzed using the Friedman, Wilcoxon signed rank and Mann-Whitney U tests, with the significance level set at 0.05. RESULTS: No significant changes in PBF perfusion units (PU) were observed in the control group over the course of the study. However, PBF in the study group increased significantly from T0 (3.6 ± 0.2 PU) to T1 (3.7 ± 0.2 PU, p < 0.001) and decreased severely from T1 to T2 (3.3 ± 0.1, p < 0.001). PBF in the study group was still significantly lower at T3 (3.4 ± 0.1 PU, p < 0.001) in comparison to T0; however, at T4 and T5, PBF was found to have returned to pre-retraction levels. CONCLUSION: The fact that PBF values returned to initial levels within one month of the initiation of retraction despite short-term, hyperaemic, regressive changes demonstrates that the changes observed in PBF during canine retraction are reversible.

Measurement of pulp blood flow rates in maxillary anterior teeth using ultrasound Doppler flowmetry.

AIM: To measure pulp blood flow rates of clinically normal maxillary anterior teeth of healthy adults using ultrasound Doppler flowmetry (UDF). METHODOLOGY: A total of 359 anterior teeth from 63 patients (mean age, 29.8 years; range, 22-52 years; 26 females and 36 males) were included. The data were collected according to tooth type (three groups: central incisors, lateral incisors and canines). An MM-D-K (Minimax, Moscow, Russia) ultrasound Doppler imaging instrument was used to measure pulp blood flow. Differences between the tooth types were analysed with one-way anova and a Bonferroni correction at the 95% confidence level. RESULTS: The mean average linear velocities during the systolic period (Vams) of the central incisors, lateral incisors and canines were 0.58, 0.58 and 0.52 cm s(-1) , respectively. There were no significant differences in the mean Vams between the tooth types (P > 0.05). CONCLUSIONS: Within the limitations of this study, the pulp blood velocities of clinically normal, maxillary anterior teeth of healthy adults were between 0.5 and 0.6 cm s(-1) . There were no significant differences in mean blood flow rates between maxillary central incisors, lateral incisors and canines.

Topographical relationship of the greater palatine artery and the palatal spine. Significance for periodontal surgery.

AIM: The aims of this study were to (1) identify the branching pattern and course of the greater palatine artery (GPA), (2) carry out a morphological analysis of the palatal bony prominence that divides the medial and lateral grooves and (3) characterize the topographical relationships between these two structures. METHODS: Thirty-six hemimaxillae were studied with the aid of a surgical microscope to elucidate the GPA. A further 25 dry skulls were examined to establish the morphology of the palatal spine. RESULTS: The most common GPA branching pattern was type I (41.7%, 15 sides), which gave off the medial and canine branches after the bony prominence. The distances from the CEJ to the lateral branch of the GPA were 9.04 ± 2.93 mm (canine), 11.12 ± 1.89 mm (first premolar), 13.51 ± 2.08 mm (second premolar), 13.76 ± 2.86 mm (first molar) and 13.91 ± 2.20 mm (second molar). The palatal spine was frequently observed as the bony prominence (66.3%, 57 sides), and was located at 6.49 ± 1.76 mm from the greater palatine foramen, with a length of 10.42 ± 2.45 mm. There was no a correlation between the bony prominence shape and the GPA branching pattern. CONCLUSIONS: These results could provide the reference data regarding the topography of the GPA for periodontal surgery.

Effect of tooth isolation on laser Doppler readings.

AIM: To measure differences between single (STI) and multiple teeth isolation (MTI), pulpal blood flow (PBF) was assessed using laser Doppler flowmetry (LDF). METHODOLOGY: Pulpal blood flow of twenty maxillary incisors with no restorations or abnormal responses to sensitivity tests in healthy patients between 24 and 42 years of age was measured in perfusion units (PU). STI (isolation of only the tooth undergoing blood flow assessment) and MTI (isolation including the maxillary right to the maxillary left canine) recordings were taken with regular blood flow (RBF) and with local infiltration (LI) with vasoconstrictor. anova and Tukey HSD tests were used for statistical analysis. RESULTS: The mean PBF with regular blood flow conditions was significantly different between single tooth isolation [5.53 PU (SD ± 2.98)] and multiple tooth isolation [2.85 PU (SD ± 2.13)] (P < 0.01). When local anaesthesia was administered (LI), the PBF was significantly different between single tooth isolation [2.95 PU (SD ± 2.48)] and multiple tooth isolation [1.32 PU (SD ± 0.70)] (P < 0.05). Significant differences in PBF also existed between single tooth isolation under regular blood flow conditions and with local anaesthesia (P < 0.01), between single tooth isolation under regular blood flow conditions and multiple tooth isolation with local anaesthesia (P < 0.01), and between multiple tooth isolation under regular blood flow conditions and with local anaesthesia (P < 0.05). CONCLUSIONS: Pulpal blood flow measurements could be obtained with multiple teeth isolation and single tooth isolation. Multiple teeth isolation blocked signal contamination better. Single tooth isolation provided significantly different readings for regular blood flow and LI conditions and may therefore provide an option for pulpal blood flow assessment with LDF.

Monitoring dental pulp sensibility and blood flow in patients receiving mandibular orthognathic surgery.

AIM: To investigate the effect of orthognathic surgery, in particular genioplasty, on pulp sensibility and pulp blood flow (PBF). METHODOLOGY: Pulp blood flow monitoring and CO(2) pulp sensibility testing were performed on 101 mandibular anterior teeth from 17 subjects who received mandibular bilateral sagittal split osteotomy (BSSO) with or without genioplasty and other maxillary surgical procedures combined with orthodontic treatment. A laser Doppler flowmeter was used to monitor PBF using customized acrylic splints for each subject. Preoperative baseline scores were recorded from up to 1 week preoperatively, and subsequently monitored for up to 18-28 weeks postoperatively. The data were analysed by RMANOVA and pairwise comparisons. Statistical significance was defined as P < 0.05. RESULTS: The average PBF in subjects who received genioplasty was not significantly different to those who received no genioplasty (F = 0.076, P = 0.784). In both groups, PBF decreased significantly postoperatively (F = 23.323, P = 0.000) and remained significantly lower (P = 0.000) than preoperative values at all times. PBF decreased markedly for 1-2 weeks postoperatively in patients who received genioplasty. However, there were no statistical differences between the PBF values at any time postoperatively for either group (P > 0.05). All teeth in both groups responded to CO(2) preoperatively. The average number of teeth that responded to CO(2) postoperatively in the genioplasty group was lower without significant difference when compared to the group without genioplasty (binomial distribution F = 2.63, P = 0.1256, normal distribution F = 2.98, P = 0.1048). At each progressive period after 1-2 weeks following surgery, the number of teeth responding to CO(2) increased significantly (P < 0.001) in both groups. At the end of the study, in the genioplasty group 81.1% of teeth responded to CO(2) compared to all teeth in the group without genioplasty. CONCLUSION: Pulp blood flow decreased and remained significantly lower than preoperative values in mandibular anterior teeth postoperatively with or without genioplasty. At no time was the absence of PBF recorded. The number of teeth that responded to CO(2) decreased markedly postoperatively but recovered significantly over time. All teeth regained sensibility in the group without genioplasty at the end of the study. There were neither common trends nor coincidence in the recovery of PBF and pulp sensibility.

Variations of vascular distribution in the mandibular anterior lingual region: a high risk of vascular injury during implant surgery.

PURPOSE: To clarify variations of vascular distribution around the mandibular anterior tooth lingual region, an area in which vascular injuries have often been reported during dental implant surgery. The reasons for such injuries in this region are discussed from an anatomical perspective. MATERIALS AND METHODS: Anatomical dissections were performed on 100 sides of 50 cadavers used for anatomy education. Ten sides of 5 cadavers were injected intravascularly with methyl methacrylate, and penetration of the mandible was closely evaluated. RESULTS: In the mandibular anterior tooth lingual region, both the sublingual and submental arteries showed various distribution patterns. Distal branches basically penetrated the bone. CONCLUSIONS: In the mandibular anterior tooth lingual region, the sublingual and submental arteries traveled from the vicinity of the mylohyoid muscle attachment along the bone surface in an anterosuperior direction. Many of these blood vessels penetrated the alveolar mucosa in the anterior tooth region, and many distal branches of the vessels also finally penetrated the bone. This seems to explain why many vascular injuries are encountered around the mandibular anterior tooth lingual region during implant surgery.

Assessment of pulp blood flow in primary and permanent teeth using pulse oximetry.

Pulse oximetry (PO) is a well-accepted non-invasive method for assessing vascular health, based on oxygen saturation (SaO(2) ) measurements. The objectives of this study were to design and build a custom-made PO dental sensor holder, to evaluate the effectiveness of PO in determining pulp blood flow in primary and permanent teeth, and to compare the SaO(2) levels obtained in teeth and on the little finger of patients. The PO sensor adapted to the custom-made sensor holder is termed as a device to position and hold the PO sensor. This study evaluated SaO(2) readings obtained in the pulp of 123 teeth of 84 children aged 4-13years. The teeth were divided into three groups: group I - primary teeth: 23 central incisors and 28 canines; group II - permanent teeth: 25 central incisors and 28 canines; and group III - endodontically treated teeth (control): 12 permanent central incisors and seven primary central incisors. The pulp blood flow and SaO(2) were measured and were compared with readings of the patient's finger. Data were analyzed by paired t-tests and Pearson's analysis method. The PO was able to identify all the clinically normal pulps contained in the sample, and all the endodontically treated teeth (controls) showed no response. The mean SaO(2) values were 85.27% in the teeth and 92.85% in the fingers. In conclusion, PO readings were effective in determining pulp blood flow in primary and permanent teeth. However, there was no correlation between the SaO(2) values in the fingers and in the teeth of the patients (P<0.05).

Effect of simulated pulpal microcirculation on intrapulpal temperature changes following application of heat on tooth surfaces.

AIM: To evaluate ex vivo whether a simulated pulpal microcirculation inside a pulp chamber influenced intrapulpal temperature rise following application of heat on tooth surfaces. METHODOLOGY: An ex vivo model that allowed the circulation of 37 degrees C warm water inside the pulp chamber of an extracted human tooth was designed. The experimental model resembled pulpal microcirculation. After application of specific thermal stimuli for 30 s to the external surface of 15 maxillary central incisors, lateral incisors and canines, temperature changes were measured in the pulp chamber. The Greenhouse-Geisser and Bonferroni tests were used for analysis of the data. The level of significance was set at 0.05. RESULTS: Significant differences were found in all three groups of teeth between temperature measurements with or without intrapulpal water flow. Additionally, temperature changes resulting from the application of different stimuli to the group of lateral incisors were significantly greater compared with the other groups of teeth (P < 0.05). CONCLUSIONS: The importance of the cooling effect of simulated pulp microcirculation in the thermal behaviour of the dentine was established. Thickness of tooth tissue influenced significantly pulp temperature rise ex vivo.

Lingual perimandibular vessels associated with life-threatening bleeding: an anatomic study.

PURPOSE: To describe the anatomy of the lingual perimandibular vessels and emphasize the distance to the bone. MATERIALS AND METHODS: The hemifacial lower third was dissected in 12 human cadavers. The blood vessels in the floor of the mouth were exposed using sagittal incisions at the canine, mental foramen, and second molar areas. RESULTS: The diameter of the dissected vessels ranged from 0.5 to 3 mm (mean, 1.5 mm). Most vessels were found superior to the mylohyoid muscle in the canine area and beneath the muscle in the mental and second molar areas. The smallest median vertical distance from blood vessel to bone was in the canine area (14.5 mm), followed by the mental foramen area (15.5 mm) and the second premolar area (19 mm). The median horizontal distance of the vessels from the lingual plate was 2 mm at the canine and second molar areas and 4 mm at the mental area. DISCUSSION: Lingual plate perforation, especially anterior to the canine area, can easily injure blood vessels in the floor of the mouth and cause life-threatening hemorrhage following implant placement. Bleeding can occur when the mandibular lingual plate is perforated. Care should be taken to recognize situations where this complication may occur. CONCLUSIONS: Based on the study of human cadavers, it appears that vessels in the floor of the mouth are sometimes in close proximity to the site of implant placement. Caution should be exercised when placing implants in this area.

Assessment of the efficacy of an indigeniously developed pulse oximeter dental sensor holder for pulp vitality testing.

Current routine methods of assessment of pulp vitality rely on stimulation of nerve fibres and give no direct indication of blood flow within the pulp. Pulse oximeter is a proven, atraumatic method of measuring vascular status, by evaluating oxygen saturation. This study explores the use of customized dental pulse oximeter sensor holder to assess pulpal vascular oxygen saturation in permanent teeth. Pulse oximeter readily differentiated between known vital and nonvital teeth. Vital teeth consistently provided oxygen saturation values that were lower than the values recorded on the patient's fingers. Pulse oximeter is an accurate, atraumatic clinical alternative to the present electrical and thermal methods of assessing pulp vitality in teeth.

Pulp revascularization of a severely malformed immature maxillary canine.

Dens invaginatus (DI) is a dental anomaly exhibiting complex anatomical forms. Because of this anatomical complexity, immature DI teeth with necrotic pulp are difficult to treat via apexification. We used revascularization as an alternative treatment for a patient with DI. An 11-year-old boy visited our clinic with chief complaints of gingival swelling and pain in the left maxillary canine. Clinical and radiographic findings were consistent with a diagnosis of type III DI. Revascularization therapy was performed, and a 24-month follow-up examination confirmed healing of the periapical radiolucency and physiological root formation. (J Oral Sci 58, 295-298, 2016).

Quantification of pulpal blood flow in developing teeth of dogs.

Pulpal blood flow was determined in 32 dogs ranging in age from 6 weeks to 18 months by the isotope fractionation method incorporating diffusible and nondiffusible tracers. Dogs were placed into selected age groups by the developmental status of the canine teeth. For the teeth sampled, the maxillary first, second, and third incisors along with the canines and first molars, pulpal blood flow was determined to be not different in teeth at various developmental stages. For some dental pulps, alveolar mucosa, and bone, the tracers were not determining equivalent blood flows. Because of incomplete trapping of the 7- to 10 mu microspheres and the flow limitation of 86Rb, the 15 mu spheres would appear to be a reliable indicator of "total" blood flow to pulpal tissues. However, in alveolar mucosa and bone, and 15 mu microspheres may not be completely trapped and thus, may underestimate blood flow to these tissues. Within the age range of these dogs, tissue blood flow was not dependent upon the stages of oral development.

The sources of laser Doppler blood-flow signals recorded from human teeth.

Records of pulpal blood flow obtained from human teeth with a laser Doppler flowmeter include a very large component derived from periodontal and other tissues outside the pulp, but this contamination can be reduced by covering the surrounding tissues with opaque rubber dam. The present experiments were carried out to determine what proportion of the signal obtained with this dam in place is derived from non-pulpal tissues. Recordings were made from 22 healthy, intact upper incisors in 14 individuals (aged 22-40 years) with and without dam under the following conditions: from the intact teeth, after local anaesthesia (LA) and the preparation of a deep cavity in the incisal third of the labial surface of the tooth, and after removal of the pulp and arrest of bleeding. In some cases, a reading was also made after replacing the pulp in the pulp cavity. The rubber dam reduced significantly (P<0.05) the mean blood flow reading from the intact teeth by 73%, from 6.98 arbitrary perfusion units (PU) (+/-1.30 S.D., n=22) to 1.92+/-1.50 PU. After LA and cavity preparation, the mean signal with dam was 1.45+/-0.61 PU (n=16). This fell significantly by 76% to 0.35+/-0.19 PU (n=16) when the pulp was removed but not replaced, and by 43% to 0.98+/-0.36 PU (n=14) when the pulp was removed and replaced in the pulp cavity. The latter condition is thought to reproduce most closely the scattering of light in an intact tooth. The results confirm previous findings that up to 80% of the laser Doppler blood-flow signal recorded from an intact human tooth without rubber dam is of non-pulpal origin. They also show that only approximately 43% of the signal recorded with an opaque rubber dam is from pulp.

Pulp interstitial fluid pressure and blood flow after denervation and electrical tooth stimulation in the ferret.

The effects of sensory and sympathetic denervation on simultaneously measured interstitial fluid pressure and blood flow in the canine pulp before, during and after electrical tooth stimulation were investigated in 25 ferrets. The micropuncture technique was used to measure interstitial fluid pressure and laser-Doppler flowmetry was used to record pulpal blood flow. Animals with an intact innervation (group 1) served as controls. Sensory denervation was by axotomy of the left inferior alveolar nerve 10 days before the experiment (group 2) and sympathectomy by removal of the left cervical ganglion 5 days before the experiments (group 3). The study was designed to verify whether denervation affected basal pulp blood flow and interstitial fluid pressures during control conditions and/or after tooth stimulation. During control conditions the interstitial fluid pressure averaged 1.32 +/- 0.07 kPa in group 1, whereas the mean was only 0.51 +/- 0.13 kPa in the axotomized animals (group 2). The difference was highly significant, indicating decreased blood or interstitial fluid volume in the pulp after inferior alveolar nerve axotomy. In the sympathectomized group neither the interstitial fluid pressure nor the pulp blood flow was significantly different from those of group 1. Electrical tooth stimulation caused an almost simultaneous increase in interstitial fluid pressure and pulp blood flow in groups 1 and 3, whereas stimulation did not significantly change either variable in the axotomized animals (group 2). It is concluded that a resting nervous vasodilator tone of sensory origin exists in the ferret dental pulp, and that the sensory nerves are responsible for the increased interstitial fluid pressure and pulp blood flow during tooth stimulation.

Increased blood flow and nerve firing in the cat canine tooth in response to stimulation of the second premolar pulp.

Mustard oil or mechanical stimulation was applied to maxillary second premolar tooth pulps and pulpal blood flow and or intradental nerve activity in the ipsilateral canine tooth were recorded in the cat. Mustard oil application to the second premolar pulp significantly increased blood flow in the canine tooth pulp to 162.0+/-65.8% (n = 16) of the prestimulation flow compared to control data obtained with application of mineral oil (107.0+/-5.1%, n = 6) (Mann-Whitney U-test, p = 0.0009). Sectioning of the infraorbital nerve and its branches on the experimental side (n = 4) did not affect this increase in pulpal blood flow. The paraperiosteal injection of 2% lidocaine (1.0 ml) without vasoconstrictor significantly inhibited the increase in canine pulpal blood flow induced by mustard oil application to the second premolar pulp (109.8+/-6.8% of the prestimulation level, n = 7) (Mann-Whitney U-test, p = 0.0013). Sporadic firing or sometimes bursts of action potentials in the canine pulp nerves were recorded during and/or after the mustard oil application to the second premolar pulp in three of 16 cases. Four single pulp nerve units firing in synchrony with the mechanical stimulation of the second premolar pulp were recorded in two of eight canines, which substantiated the existence of branched afferents innervating both teeth. These findings suggest that stimulation of the second premolar pulp may induce axon reflex-related vasodilation and intradental nerve firing in the canine pulp via branched afferent fibres innervating both the second premolar and canine teeth.

Pulpal blood flow: effects of corticotomy and midline osteotomy in surgically assisted rapid palatal expansion.

INTRODUCTION/PURPOSE: Surgically assisted rapid palatal expansion is used for the management of transverse maxillary deficiency in the early permanent dentition. The success depends on the maintenance of an adequate blood supply to the mobilized segments. The aim of this study was to assess the effects of corticotomy and midline osteotomy on the tooth pulpal blood flow. MATERIAL: Laser Doppler flowmetry was applied as a non-invasive and reliable technique for the assessment of pulpal blood flow in the maxillary centrals, canines and first molars. The blood flow was investigated pre- and postoperatively, on the first, third, and seventh postoperative days bilaterally in 13 cases. RESULTS: The results of this study indicate that ischaemia of the pulp can occur following osteotomy at the Le Fort I level. CONCLUSION: Corticotomy 5mm above the dental apices and separating the midpalatal suture did not have any serious effect on pulpal blood flow in this study.

Pulpal blood-flow characteristics of maxillary tooth morphotypes as assessed with laser Doppler flowmetry.

OBJECTIVE: The purpose of this study was to determine the effect of tooth morphotype on intraindividual and interindividual variations of baseline data as well as on temporal variations between testing intervals in the assessment of pulpal blood-flow by means of laser Doppler flowmetry. STUDY DESIGN: In 14 volunteers, maxillary incisors, canines, premolars, and first molars were investigated bilaterally by laser Doppler flowmetry to assess local pulpal blood-flow values. Measurements in perfusion units were taken during 3 sessions, with a time interval of 7 days between sessions. RESULTS: Intraindividual comparisons of tooth morphotype-related pulpal blood-flow values revealed significant differences only for the first molar, whereas significant interindividual differences were found for the lateral incisor, canine, premolars, and first molar. Pulpal blood-flow values for the second premolar (11.1 perfusion units) were significantly higher and those for the central incisor (7.6 perfusion units) significantly lower than those for the lateral incisor (9.2 perfusion units) and first molar (9.4 perfusion units). In contrast, measurements at the lateral incisor, first premolar, and first molar did not differ significantly (P > .05). Multiple testing showed no statistically significant effect on tooth morphotype-related pulpal blood-flow measurements. CONCLUSIONS: The findings indicate that contralateral incisors, canines, and premolars are appropriate intraindividual controls for local pulpal blood-flow recordings. Other studies may identify the effect of environmental and technique-related factors on the assessment of local pulpal blood-flow values.

Blood flow changes in human dental pulps when capsaicin is applied to the adjacent gingival mucosa.

OBJECTIVE: The purpose of this study was to determine whether changes occur in pulpal blood flow when capsaicin is applied to the adjacent gingival or alveolar mucosa in human beings. STUDY DESIGN: Laser Doppler flowmetry was used to measure changes in pulpal blood flow (PBF) after applying capsaicin to adjacent gingival mucosa in 20 human volunteers. The procedure was repeated on 10 subjects after administration of an ipsilateral inferior alveolar nerve block and on the other 10 subjects after application of topical anesthetic to their adjacent gingival and alveolar mucosa. RESULTS: PBF increased in 16 subjects and did not change in 4 subjects after capsaicin application. Ipsilateral inferior alveolar nerve block did not alter this effect. Pretreatment with topical lidocaine resulted in no change or decreased PBF in 8 subjects and increased PBF in 2 subjects. CONCLUSION: Changes occur in the PBF of the mandibular canine teeth of some humans when capsaicin is applied to the adjacent gingival or alveolar mucosa.