Changes In Pulpal Blood Flow Research Articles

Pulp fiction or pulp fact-does orthodontics damage pulpal tissue?

Electronic databases PubMed, Scopus and Embase were systematically searched and restricted to articles published between February 2009 and 2022. Studies were categorized using the modified method by the Swedish Council of Technology Assessment in Health Care. 20 studies were included, one of which was categorized as high quality (Grade A) and 19 of which were of moderate quality (Grade B). Exclusion criteria included articles with insufficient descriptions of reliability and reproducibility testing, review articles and case reports, and studies including traumatised teeth. Three independent authors examined titles, abstracts and full texts of relevant articles against the inclusion criteria. Disagreements were resolved by discussion. Retrieved studies were assessed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data extracted included tooth movement performed, the appliance and force used, follow-up of subjects, changes in pulpal blood flow (PBF), tooth sensibility, expression of inflammation-related proteins, along with pulpal histology and morphology changes during tooth movement (intrusion, extrusion and tipping). Overall risk of bias was unclear. A reduction in pulpal blood flow and tooth sensibility due to the application of orthodontic forces was reported by studies included in the review. Increases in the activity of proteins and enzymes related to inflammation of the pulp was reported. Two studies reported histological changes of the pulpal tissues related to orthodontic treatment. Orthodontic forces cause multiple temporary detectable changes in the dental pulp. The authors conclude there are no clear signs of permanent pulpal damage to healthy teeth due to the application of orthodontic forces.

Pulp blood flow changes in maxillary and mandibular anterior teeth after orthodontic retraction: a prospective study

BackgroundPrevious studies of pulpal blood flow (PBF) changes in anterior teeth have been limited in the early phase of orthodontic treatment; less is known about the blood supply of anterior teeth in bimaxillary protrusion patients after orthodontic retraction.MethodsFifty bimaxillary protrusion patients (25 orthodontic patients ready for debonding and 25 non-orthodontic patients) were selected as study participants. The PBF of maxillary and mandibular anterior teeth were measured using laser Doppler flowmetry. For orthodontic patients, the PBF was measured at 1 day (T1), 1 month (T2), and 3 months (T3) after fixed appliance removal. Non-orthodontic patient PBF was measured as a control. Cone-beam computed tomography (CBCT) examinations before and after orthodontic treatment were performed for orthodontic patients to measure the root resorption. The anterior teeth in orthodontic group were further divided into subgroups according to root resorption and patient age.ResultsAt T1 and T3, PBF changes did not differ significantly between the orthodontic and non-orthodontic groups. Maxillary lateral incisor, maxillary central incisor, and mandibular lateral incisor PBFs at T2 were significantly higher in the orthodontic group (P = 0.048, P = 0.04, and P = 0.021). No significant difference in PBF was found between the root resorption and non-resorption subgroups at any time point. Adolescent patients showed a higher PBF in the maxillary lateral incisor at T2 (12.23 ± 3.48) relative to that at T1 (9.10 ± 3.76) and T3 (9.81 ± 2.80) with statistically significant difference (P = 0.020).ConclusionFor bimaxillary protrusion patients with four premolars extraction, PBF in the maxillary anterior teeth increased transiently after orthodontic appliance removal and then returned to non-orthodontic levels 3 months later. This effect was more pronounced in adolescents. The PBF of anterior teeth after orthodontic retraction may not be influenced by root resorption.

Effects of Local Anesthetics With Vasoconstrictors on Dental Pulp Blood Flow and Oxygen Tension.

The aim of this study was to investigate the changes in pulpal blood flow (PBF) and pulpal oxygen tension (PpulpO2) after injecting local anesthetics with vasoconstrictors. Under general anesthesia, male Japanese White rabbits were injected with 0.6 mL of 2% lidocaine with 1:80,000 epinephrine (LE) or 3% propitocaine (prilocaine) with 0.03 IU felypressin (PF) at the apical area of the lower incisor. Relative to baseline, PBF and PpulpO2 significantly decreased 5 minutes after LE or PF injection as compared with saline. The decrease in PBF was significantly lower in the LE group than in the PF group. Although the LE group had a larger decrease in PpulpO2 relative to baseline than the PF group did, that difference was not significant. PBF and PpulpO2 recovered to baseline faster in the PF group than in the LE group. The injection of local anesthetic solutions containing vasoconstrictors (LE or PF) transiently caused significant decreases in PBF that resulted in significant decreases in PpulpO2. The recovery of PpulpO2 was faster than PBF regardless of the vasoconstrictor used.

Time-course of the effect of potassium oxalate in the treatment of hypersensitive dentine in man

ObjectiveInvestigate the cause of hypersensitive dentine (HD) by recording the time course of changes in dentine sensitivity, sensory threshold to electrical stimulation (ET) and pulpal blood flow (PBF) following tubular occlusion using in vitro and clinical experiments. DesignNineteen teeth with HD and 13 with normal dentine from 8 participants were evaluated, and the intensity of any pain produced by various stimuli was recorded at different times after oxalate treatment. The participants used a visual-analogue scale (VAS) to indicate the intensity of any pain. The ET and PBF were recorded at the same times. ResultsPreliminary in vitro experiments showed that oxalate treatment had no effect on the method used to record PBF, and blocked the treated tubules immediately after application. Considering teeth with HD, a decrease in the median VAS evoked by all forms of stimulation was observed at all post-treatment times, except immediately after treatment (p < 0.05), while the treatment produced no significant effect in teeth with normal dentine. No significant changes in ET or PBF was observed in any of the groups. ConclusionsThe effect of oxalate in relieving the symptoms of HD is not only due to a reduction in the intensity of stimulation of sensory receptors sensitive to fluid flow in the dentinal tubules, but also to a reduce in the sensitivity of the receptors that respond to dentine stimulation. There was no evidence that acute pulpitis or central sensitization to pain, which would be associated with changes in PBF or ET, contributes to HD.

Pulpal blood flow changes and pain scores related to using Superelastic 0.018-inch Nickel Titanium as the first orthodontic alignment archwire: a prospective clinical trial.

Background Optimal orthodontic force results in maximum rate of tooth movement without tissue damage. Even though starting orthodontic treatment with a thicker archwire may shorten treatment duration, the evidence on the effect of using 0.018-inch NiTi as the first alignment archwire on pulpal blood flow (PBF) status is still scarce.Objectives to record PBF changes and pain scores associated with using 0.018-inch NiTi as the first alignment archwire during fixed orthodontic treatment.Methodology Patients were selected from subjects attending postgraduate orthodontic teaching clinics at Jordan University of Science and Technology. In total, forty healthy patients who exhibited mild lower arch crowding were included. A split-mouth trial design was used. Each patient received two archwire sizes at one time joined in the midline by crimpable hook and applied in the lower arch. Patients were assigned into one of two groups based on archwire sizes used. Group 1: 0.014-inch and 0.018-inch NiTi (Six males, 14 females aged 19.4±1.33 years) and Group 2: 0.016-inch and 0.018-inch NiTi (Seven males, 13 females aged 19.6±1.45 years). The archwire size group was randomly allocated with a 1:1 allocation ratio. A Laser Doppler Flowmeter was used to measure PBF at different time intervals (T0-T5). Pain scores were recorded using a visual analogue scale (VAS). A repeated measures ANOVA and a post-hoc Bonferroni comparison tests were conducted to examine differences at the different time points before and during orthodontic alignment.Results For all studied archwire sizes, PBF decreased 20 minutes after their placement. Most PBF changes occurred within 24hours and continued to decrease until 72 hours after archwire placement where the maximum reduction was reached. Eventually, normal values were reverted within 1 month. PBF changes were similar between all alignment – groups.Conclusions Initial orthodontic alignment with 0.018-inch NiTi does not cause irreversible changes to pulpal vasculature or produces higher pain scores.

A comparative study of initial changes in pulpal blood flow between conventional and self-ligating fixed orthodontic brackets during leveling and alignment stage.

To evaluate and compare the initial changes in pulpal blood flow (PBF) between conventional and self-ligating fixed orthodontic brackets during leveling and alignment stage using 0.016 × 0.022 NiTi as alignment archwire. Twenty-two patients (16 females and 6 males) aged 19.00 ± 2.53 years who presented with mild lower arch crowding were selected to participate in the study. A split mouth study design was applied for each patient. The intervention (self-ligating brackets) was randomly allocated to the right or left side of the patient using the permuted random block size of 2 with 1:1 allocation ratio. Two different fixed appliance brackets were used in the lower arch (self-ligating brackets on one side and conventional brackets on the other side of the same patients. Two alignment archwires; 0.016″ NiTi and 0.016 × 0.022″ NiTi were used in this study. PBF was measured for the lower right and left sides using laser Doppler flowmetry at different time intervals (20 min, 24 h, 72 h, 1 week, and 1 month) RESULTS: PBF started to decrease 20 min after insertion of both archwires using both types of brackets. Maximum decrease was reached after 72 h of archwire insertion. After 1 week of force application, PBF started to increase to restore its original values after 1 month. Differences between the 2 groups were not significant (P > 0.05). In both treatment groups, PBF reduced within 48 h. PBF started to increase after 1 week until it reached its original values after 1 month. Changes in PBF at the measured time intervals in the two groups were similar. The use of 0.016 × 0.022″ NiTi immediately after 0.016″ NiTi for alignment does not produce any damaging effect on the teeth.

The effect of inferior alveolar nerve block anesthesia of 4% articaine and epinephrine 1:100,000 on blood flow and anesthesia of human mandibular teeth

Background/purposeLocal anesthetics and anesthetic techniques affect the patterns of pulpal blood flow (PBF) and pulpal anesthesia in human teeth. This study aimed to determine PBF changes and pulpal anesthesia of intact mandibular first molars and canines after administration of 4% articaine with epinephrine 1:100,000 using inferior alveolar nerve block (IANB). Materials and methodsTen healthy subjects received IANB of 4% articaine with epinephrine 1:100,000. Laser Doppler flowmetry and electrical pulp testing were combined to assess PBF changes and pulpal anesthesia of intact mandibular first molars and canines. The data were analyzed using one-way repeated-measures analysis of variance and Student–Newman–Keuls test. ResultsIANB with 4% articaine and epinephrine 1:100,000 did not have any significant change in PBF for the first 20 min post injection in mandibular first molars, and for 45 min post injection in the canines (P > 0.05). However, a hyperemic response occurred during 25–60 min post injection in the molars, and between 60 and 75 min post injection in the canines (P < 0.05). Thereafter, the PBF in both teeth returned to the baseline. Onset of pulpal anesthesia was 8.60 ± 2.12 min in the molars, and 9 ± 1.94 min in the canines. Duration of pulpal anesthesia was 82.40 ± 41.56 min in the molars, and 84 ± 47.40 min in the canines. ConclusionIn case of successful IANB, 4% articaine and epinephrine 1:100,000 caused insignificant changes in PBF up to 30 min but a hyperemic response at later time points. Thereafter, the PBF returned to the baseline.

A comparative study of initial changes in pulpal blood flow between clear aligners and fixed orthodontic appliances

The objective of this study is to evaluate and compare the initial changes of pulpal blood flow (PBF) using clear aligner and fixed orthodontic treatment. A total of 45 subjects were subdivided into 2 groups: group 1; 25 subjects treated with preadjusted edgewise fixed appliance with 0.014″ nickel titanium as the alignment archwire and group 2; 20 subjects treated using clear aligner. In both groups, PBF was measured for the maxillary right and mandibular left teeth using Laser Doppler flowmetry at different time intervals (20minutes, 48hours, 72hours, and 1month) after the fitting of the nickel titanium archwire in group 1 and after the delivery of the second aligner in group 2. A repeated-measures analysis of variance and a Bonferroni post-hoc comparison test were applied to determine differences at the various time intervals. The PBF decreased in both types of appliances after force application. The maximum reduction in PBF was reached after 72hours. It returned to its normal values within 1month. The differences in PBF between the 2 groups did not reach any statistical significance. PBF in orthodontically treated teeth decreased 20minutes after orthodontic force application in both fixed and clear aligner appliances. In both treatment groups, most changes occurred within 48hours of force application. PBF returned to its normal values within 1month. Changes in PBF in both treatment groups were comparable.

Histological response in dental pulp of accelerate tooth movement using periodontal ligament distraction osteogenesis in dogs

PurposeThis study compared initial histological change in dental pulp in response to periodontal ligament distraction osteogenesis (PLDO) with that to conventional orthodontic treatment to determine the effectiveness of PLDO. Materials and methodsPLDO was performed on the right side (PLDO group) and conventional orthodontic treatment on the left side (CCS group) in 6 male beagle dogs. Untreated teeth served as a control group. Radiographs were obtained after appliance activation. Change in pulpal blood flow was measured using a Doppler blood flow meter. The sections were stained with hematoxylin-eosin and Masson’s trichrome for morphological observation. Cell response was observed by immunohistochemistry using proliferating cell nuclear antigen (PCNA) and the TUNEL method. ResultsThe total movement distance of the premolar was significantly greater in the PLDO group than in the CCS group. A decrease in pulpal blood flow and the number of odontoblast cells was observed together with dental pulp capillary dilation at 5 and 12 days after appliance attachment in both groups. While many TUNEL-positive cells were observed on the 5th day in both experimental groups, they showed a decrease at 12 days. More PCNA-positive cells were observed on the 12th day than on the 5th day in both groups. There was no difference in invasiveness between the pulpal reaction to PLDO and that to conventional orthodontic treatment, suggesting that the level of recovery is similar. ConclusionPLDO enabled rapid tooth movement and initial histological change in the dental pulp was similar to that in response to conventional orthodontic treatment.

Pulpal and Periodontal Tissues Changes Associated with Le Fort I and Sagittal Split Ramus Osteotomies: A review.

Introduction:Le Fort I and sagittal split ramus osteotomies are the most commonly performed orthognathic surgery procedures on the maxilla and mandible, respectively.Techniques: Despite progress in the techniques, these procedures may still be associated with morbidity, expressed as inflammation, inadequate bony union, periodontal damages or in extreme cases even total bone loss.Discussion: Through a comprehensive review of the literature, the influences of maxillary and mandibular surgery on Pulpal Blood Flow (PBF), pulp sensitivity and pulp vitality are examined. Moreover, adverse effects of maxillary surgery on tooth color and periodontal tissues are also reported. The effects had a variety of expression. Concerning maxillary surgery, some studies showed an initial increase in PBF followed by a decrease to the baseline or even lower levels after 1-3 months. Other studies found an initial decrease in PBF followed by an increase soon after. There were also studies that showed no significant PBF changes, in contrast.Conclusion: Concerning mandibular surgery, a recent study showed a decrease in PBF immediately after sagittal split ramus osteotomy. Some authors detected tooth discoloration of maxillary teeth after Le Fort I osteotomy. Root resorption and root injury were also detected, but were of minor significance. Usually, these adverse effects derive from injury of the vessels of the palatal pedicle. This pedicle should be maintained intact for the avoidance of blood flow impairments. In addition, the descending palatine artery should be protected during maxillary surgery procedures in order to maintain the highest possible blood flow on the maxillary teeth.

A Clinical Study on the Effect of Injection Sites on Efficacy of Anesthesia and Pulpal Blood Flow in Carious Teeth.

This randomized clinical trial evaluated the efficiency of maxillary infiltration anesthesia in carious teeth at two different injection sites and their impact on the laser Doppler recordings of pulpal blood flow (PBF) during a caries excavation procedure. The null hypothesis tested was that there are no differences in the efficiency of anesthesia and PBF reduction between maxillary infiltrations at the two injection sites. One hundred twenty patients were divided into three groups according to the degree of carious lesion of their maxillary left central incisors (moderate caries, deep caries, or no caries). Forty patients in each group randomly received infiltrations over the root apex of maxillary left central incisors (site X) or over the midpoint of the line connecting the root apexes of both maxillary left central and lateral incisors (site Y) using 0.9 mL 2% lidocaine with 1:100,000 adrenaline. Teeth were pulp tested at five-minute intervals after injection except for the period of cavity cutting, which was done 12 minutes after injection. The PBF changes after injection were monitored by laser Doppler flowmetry. The observation period in this study was 60 minutes. Success of anesthesia was defined as no or mild pain on cavity cutting by visual analog scale recordings. Deep caries group showed significantly higher baseline PBF ( p<0.05). All groups showed 100% success of anesthesia and similar duration time ( p>0.05). Subgroups that had the injection at site Y showed significantly less reduction of PBF ( p<0.05). Cavity-cutting procedures increased the amplitude of the PBF around the lowest value after injection. Independent of the cavity depth, carious anterior teeth anesthetized by infiltration further from the apex had significantly less reduction on the pulpal blood flow compared with teeth anesthetized by infiltration at the apex.

Effect of full crown preparation on pulpal blood flow in man

ObjectiveTo determine if full crown preparation causes an increase in pulpal blood flow (PBF), indicating inflammation, in human subjects. DesignThe experiments were carried out on 35 intact, mandibular posterior teeth in 13 subjects: 32 were abutments for 16 fixed bridges that replaced first molars; the other 3 were first premolars adjacent to abutment teeth that served as un-operated controls. Crown preparations were made using an air-rotor with water-spray under regional block anaesthesia (4% articaine with epinephrine 1:100,000). PBF was recorded with a laser Doppler flow meter (LDF) before and after administering the anaesthetic, with the LDF probe on the buccal enamel. PBF was then recorded from the abutment teeth with the probe on buccal dentine after preparing the buccal surfaces of both teeth, after completing the crown preparations, and after 1 and 7days. PBF was also recorded from the buccal enamel of the control teeth on each occasion. ResultsThe mean±S.D. PBF values before and after anaesthesia were 2.63±2.13 and 2.42±2.38P.U. respectively, which were not significantly different (Paired t-test). The mean values for the abutment teeth after buccal preparation, after complete crown preparation, and after 1 and 7days were 5.20±2.49, 4.53±2.52, 4.92±2.98 and 5.48±2.65P.U. respectively. The 4 values for each tooth were not significantly different (two-way RM ANOVA). In the control group, the values under all six conditions were not significantly different. ConclusionsRegional block anaesthesia produced no change in PBF, nor did full-crown preparation, neither immediately after the procedure nor 1 and 7days later.

Comparative evaluation of pulpal blood flow during incisor intrusion

AbstractAimThe aim of the present study was to evaluate and compare changes in pulpal blood flow (PBF) as a result of maxillary incisor intrusion achieved by one of two methods (utility arches or mini-implants).Materials and methodsThirty subjects were divided into three groups, the first of which underwent maxillary incisor intrusion using utility arches (UA) and a second group, intrusion via mini-implants (MI). The third group acted as a control. An intrusive force of 100 g was applied to the upper incisors in the treatment groups, whereas no force was applied to the anterior teeth in the control group. A laser Doppler flowmeter (LDF) was used to measure PBF at baseline (T0) and during incisor intrusion at 24 hours (T1), three days (T2), seven days (T3) and three weeks (T4). Statistical changes in PBF were assessed by the Wilcoxon Signed Rank and Mann-Whitney U tests, with significance set atp&lt; 0.05.ResultsThe mean PBF in the UA and MI groups decreased significantly from T0 to T1 (p&lt; 0.001), slightly increased at T2 and continued to increase gradually at T3. PBF attained levels similar to those measured prior to intrusion at T4. No significant changes in PBF were observed in the control group over the course of the study. The only statistically significant difference between the UA and MI groups were at T1 and T2, at which time the MI group had lower PBF values (p&lt; 0.001).ConclusionsDespite slight regressive changes in pulpal tissue observed over the short term, PBF values tended to return to initial levels within three weeks, indicating that changes observed in PBF with the UA and MI intrusion methods are reversible. Although the changes in PBF could not be directly related to the method of intrusion employed, in general, a more severe drop in PBF was observed in the MI group during the first three days of intrusion.

Changes in dental pulp blood flow of different maxillary tooth types after Le Fort I osteotomy.

This study examined the effects of Le Fort I (LF-I) osteotomy on pulpal blood flow (PBF) in maxillary teeth during a 12-month postsurgical period. A laser Doppler flowmeter was used to measure PBF in maxillary incisors, canines, and first premolars of 14 patients undergoing LF-I osteotomy (study group), 7 patients undergoing mandibular osteotomy (surgical control group), and 7 nonsurgical controls. The PBF was measured at baseline (preoperatively) and at 1 week and 1, 3, 6, and 12 months postoperatively and at similar intervals in nonsurgical control subjects. Data were evaluated using Kruskal-Wallis and post hoc Mann-Whitney tests. Changes in PBF over time for each tooth type were evaluated using the Wilcoxon signed-rank test. The level of significance was set at P < 0.05. Study findings showed that baseline PBF values did not differ significantly between groups. Maxillary PBF in the control group did not vary over time; however, an initial decrease in PBF was observed in all tooth types immediately after surgery in the study group. A gradual increase to near-preoperative levels was then observed during a 12-month healing period. Although dramatic reductions in maxillary perfusion of the first premolar and canine pulps were observed at 1 week and 1 month after LF-I osteotomy when compared with baseline (P < 0.001), PBF significantly recovered over time. Moreover, hyperemia was observed in lateral incisors 3 months postoperatively, demonstrating a tooth type-specific effect of LF-I osteotomy on PBF.

Changes in maxillary incisor dental pulp blood flow during intrusion by mini-implants

Aim. The aim of this clinical study was to identify changes in pulpal blood flow (PBF) in human central incisors resulting from short- and long-term intrusive orthodontic forces from mini-implants. Materials and methods. A total of 40 sound upper central and lateral incisors in 20 patients scheduled for intrusion for orthodontic reasons were divided into two groups. From each group, 20 teeth were subjected to intrusive force from mini-implants (Group 1 = Light Force: 40 g; Group 2 = Heavy Force: 120 g), whereas the remaining 20 contralateral teeth were not subjected to forces from mini-implants and served as controls. Laser-Doppler flowmetry (LDF) measurements were recorded at baseline and at 3 days and 3 weeks following intrusion. Results. PBF decreased significantly at 3 days (Light Force Group: 7.72 ± 0.50; Heavy Force Group: 7.72 ± 0.52) and then increased towards baseline at 3 weeks (Light Force Group: 10.37 ± 0.58; Heavy Force Group: 10.31 ± 0.45) following intrusion. Conclusions. In other words, despite slight regressive changes in pulpal tissue in the short-term, PBF improved after 3 weeks following intrusion by mini-implants, indicating that the changes observed in PBF is reversible, even following radical incisor intrusion.

고양이 치수에서 열 자극으로 유도된 신경병증 염증에서 치수 혈류량 변화

본 연구는 열 자극으로 유도된 신경성 염증 상태에서 혈류량의 변화와 histamine의 치수혈류 조절에 관해 유기적 관계를 연구함으로써 치수혈류 조절기전을 밝히고자 하였다. 연구방법은 열 마리의 고양이를 전신마취 하에 사용되었으며, 치수혈류의 변화는 레이저 도플러 측정계(Periflux 4001, Stockholm, Sweden)을 사용하여 측정 하였다. 레이저 도플러 측정하는 프로브는 하악 견치의 치면에 위치하였다. 열 자극은 입력/출력 장치와 열 자극 제어 스크립트 파일을 사용하여 치아에 적용하였다. 열(<TEX>$40-65^{\circ}C$</TEX>)에 따라 치수 혈류량이 증가를 확인하였으며, <TEX>$55^{\circ}C$</TEX>에서 가장 큰 변화가 나타났다. 열 자극의 변화가 없는 <TEX>$45^{\circ}C$</TEX>에서 Histamine(<TEX>$5{\mu}g/kg/1ml$</TEX>)를 치아와 가까운 설 동맥으로 주입 시 열 자극만 처치한 그룹보다 현저한 증가가 나타났다. 본 연구는 열적 자극에 의해 발생된 신경성 염증상태에서 치수혈류 변화와 이에 히스타민의 기능적으로 관여함을 나타내주며, 치아 염증 상태의 기전을 밝힐 수 있는 가능성을 보여준다. This study examined the involvement of histamine in heat-induced changes in pulpal blood flow(PBF) to determine the mechanism of neurogenic inflammation in feline dental pulp. The experiments were carried out in 10 felines anesthetized with sodium pentobartial and histamine injected into the dental pulp through the external carotid artery. The change in the pulpal PBF was measured using a laser Doppler flowmeter(Periflux 4001, Stockholm, Sweden). The probe of laser Doppler flowmeter was placed on the buccal surface of the ipsilateral canine teeth. Heat was applied to the tooth using a heat stimulator controlled script file with an input/output device. The application of heat (<TEX>$40-65^{\circ}C$</TEX>) induced a significant increase in PBF. The application of histamine(<TEX>$5{\mu}g/kg/1ml$</TEX>) followed by heat(<TEX>$45^{\circ}C$</TEX>) resulted in an increase in PBF. Therefore, the results of the present study showed that heat and histamine are capable of vasoconstriction caused by neurogenic inflammation in feline dental pulp. In addition, neurogenic inflammation plays an active role in modulating the microcirculation of the dental pulp.

Evaluation of Pulpal Blood Flow Changes in Primary Molars with Physiological Root Resorption by Laser Doppler Flowmetry and Pulse Oximetry

The aim of this study was to undertake a comprehensive quantitative investigation ofpulpal bloodflow (PBF) changes in human non-carious primary molar teeth with variable degrees of root resorption by Laser Doppler Flowmetry (LDF) and Pulse Oximetry (PO) methods. Data was collected from clinically and radiographically healthy 86 mandibular primary molars which have different physiological root resorption levels (PRRLs). PRRLs for each of the teeth were assessed using periapical radiographs and teeth were subdivided into three groups. The LDF values demonstrated a significant diference (p = 0.0001) between all groups although PO did not demonstrate any difference (p = 0.109). Statistical analysis of LDF values demonstrated significant differences between Groups A and C (p = 0.0001) and Groups B and C (p = 0.008). Furthermore, positive correlations were determined between LDF values and PRRL groups (p = 0.0001) and patients' ages (p = 0.0001). In our study, it was observed that the PBF values of human primary molars measured by LDF tended to increase with the progress of physiological root resorption and age. LDF was found to be a more effective method than PO to assess the pulpal vascularity changes of human primary molars.

Doppler ultrasound to detect pulpal blood flow changes during local anaesthesia

To examine whether Doppler ultrasound can detect changes in pulpal blood flow after infiltration anaesthesia. Changes in pulpal blood flow in maxillary central incisor teeth of 18 patients (mean age 26.7 years, 13 men, five women) after infiltration anaesthesia were examined. Before infiltration anaesthesia, the pulpal blood flow was measured using Doppler ultrasound. A local anaesthetic solution containing 2% lidocaine with 1:80,000 epinephrine was injected into the submucosa above the experimental tooth. The Doppler ultrasound test was carried out at 5, 10, 20, 30, 45 and 60 min after infiltration. The parameters were Vas (maximum linear velocity, cm s(-1) ), Vam (average linear velocity, cm s(-1) ) and Vakd (minimum linear velocity, cm s(-1) ), which are indicators of the level of blood flow. The mixed procedure at the 95% confidence interval was used to examine the changes in pulpal blood flow after the injection. The linear velocity profiles (Vas, Vam, and Vakd) decreased sharply 5 min after anaesthesia and then reduced continuously for 30 min. The maximum degree of blood flow reduction in Vas, Vam and Vakd was 58%, 83% and 82%, respectively. After 30 min, the linear velocities increased gradually. The Vam returned to the pre-anaesthesia state at 60 minutes but the Vas and Vakd did not recover completely. Doppler ultrasound can detect changes in pulpal blood flow after infiltration anaesthesia. In the future, Doppler ultrasound can be used as a tool for measuring pulpal blood flow.

Partial pulp necrosis caused by excessive orthodontic force

As the dental pulp is encased with a rigid, noncompliant shell, changes in pulpal blood flow or vascular tissue pressure can have serious implication for the health of pulp. Numerous studies have demonstrated that orthodontic force application may influence both blood flow and cellular metabolism, leading degenerative and/or inflammatory responses in the dental pulp. The aim of this case report is to present a case about tooth with chronic periapical abscess which showed normal vital responses. Excessive orthodontic force is thought to be the prime cause of partial pulp necrosis. Owing to remaining vital tissue, wrong dianosis can be made, and tooth falsely diagnosed as vital may be left untreated, causing the necrotic tissue to destroy the supporting tissuses. Clinician should be able to utilize various diagnostic tools for the precise diagnosis, and be aware of the endodontic-orthodontic inter-relationship. [J Kor Acad Cons Dent 2011;36(2):149-153.]

Effective Human Pulpal Blood Flow Changes During Brief Intrusive Force Application and Continuous Orthodontic Force Application using Laser Doppler Flowmetry

Effective Human Pulpal Blood Flow Changes During Brief Intrusive Force Application and Continuous Orthodontic Force Application using Laser Doppler Flowmetry