Efficacy of laser Doppler flowmetry for the diagnosis of revascularization of reimplanted immature dog teeth

Efficacy assessment of laser Doppler imager in diagnosing the pulp vitality after dental trauma

Background/purpose

This is the first paper evaluating the efficacy of laser Doppler imager in diagnosis of pulpal vitality. The purpose of this study was to evaluate and compare the diagnostic benefits of laser Doppler imaging and electric pulp test (EPT) in dental trauma.

Materials and methods

Seven patients were selected for pulp vitality evaluation in Kaohsiung Medical University Hospital between 2018 and 2019. EPT and laser Doppler imager evaluation were performed for patients with traumatic injury to teeth. Statistical methods included the Kappa consistency test and the chi-square test. In addition, the receiver operating characteristic (ROC) curve, and the area under the curve (AUC) were used.

Results

There was a significant difference in Doppler flow values between the severe trauma group and the mild trauma group, regardless of patient self-reported symptoms (P = 0.043) or physicians' diagnostic classification (P = 0.018). For an EPT instrument, the Kappa coefficient was 0.67 and 1-year pulpal status findings were highly consistent (P < 0.001). Using a Doppler instrument, the Kappa coefficient was 0.85. According to the ROC curve, the AUC for EPT was 0.94, the AUC for Doppler was 1, and the optimal cut-off value was 31.55, indicating that both were superior diagnostic tools.

Conclusion

Both laser Doppler imager and EPT can be used as tools for diagnosing traumatic pulp necrosis. Doppler imaging instruments allow for a more timely and accurate assessment of pulp vitality in dental trauma. In the future, ongoing research and related training are necessary for interpretation of Doppler data.

The Decisive Role of Laser Doppler Flowmetry for Pulp Preservation in Discolored Traumatized Teeth

Objective: It has been stated that blood pigments within discolored teeth may interfere with Laser Doppler Flowmetry (LDF) measurements. The aim of this study was to assess pulp vitality with LDF in a cohort of discolored traumatized teeth referred for endodontic treatment or where the referring dentist had doubts regarding maintained tooth vitality. Background: Discoloration of teeth is a common sequel of dental trauma. Still today, it is taken as an indicator for root canal treatment. Transient apical breakdown (TAB) is confused with apical periodontitis, although it is a sequel of dental trauma in young mature teeth and will result in revascularization and dissolution of the apical radiolucency. Methods: A total of 26 patients with 28 discolored teeth, belonging to a cohort of referred patients with traumatized teeth referred for root canal treatment and/or pulp vitality assessment were screened on color with photographs by three investigators, with traditional sensibility tests and with a Moor VMS II LDF meter. Results: The color of the intrinsically discolored teeth was grayish in 58% of teeth, blue 20%, pink/crimson 12%, and yellow 4%. Eighty-five percent were central maxillary incisors, 11% were mandibulary incisors. Thanks to LDF, 43% of the trauma cases in this small cohort with discoloration underwent root canal treatment instead of 70% with traditional sensibility tests as indicator. TAB was found in 11%. Conclusions: LDF was decisive in diagnosing vitality of discolored teeth and there was no negative impact of tooth discoloration on LDF measurements.

Efficiency of new custom-made pulse oximeter sensor holder in assessment of actual pulp status

Aim

This study aims to assess the diagnostic accuracy of new custom-made pulse oximeter sensor holder in assessment of actual pulp status with three pulp sensibility tests.

Materials and Methods

Seventy-nine single canal teeth requiring endodontic therapy was included in the study. The tooth that was requiring root canal treatment was tested with heat test, cold test, electric pulp test, and pulse oximeter. Between each test, a time period of 2 min was allowed. The response from three pulp sensibility tests and the reading from pulse oximeter were recorded. Following which root canal treatment was performed. The result obtained from four pulp tests were correlated with the clinical finding after access cavity preparation. The data obtained was statistically assessed. Receiver operator characteristic (ROC) curve analysis was performed to assess the efficacy of the pulp tests. In the above statistical tools, the probability value. 05 is considered as significant level.

Results

The overall diagnostic accuracy was found to be significantly higher with pulse oximeter when compared with other three pulp sensibility tests. The ROC curve demonstrates the results obtained from pulse oximeter was found to be more reliable than other pulp tests.

Conclusion

Within the limitation of the study, diagnostic accuracy of pulse oximeter with custom made sensor holder was reliable and accurate in assessment of actual pulp status.

Applications of sensory and physiological measurement in oral-facial dental pain

Dentists regularly employ a variety of self‐report and sensory techniques to aid in the diagnosis and treatment of tooth‐related disease. Many of these techniques leverage principles borrowed from psychophysics, the quantitative measurement of the relationship between stimuli and evoked sensations, which falls under the larger umbrella of quantitative sensory testing (QST). However, most clinicians fail to meet the bar for what could be considered quantitative sensory testing, and instead focus on qualitative and dichotomous “yes/no” aspects of sensory experience. With our current subjective measurements for pain assessments, diagnosis and treatment of dental pain in young children and individuals (any age) with severe cognitive impairment rely extensively on third‐party observations. Consequently, the limitation of inadequate pain diagnosis can lead to poor pain management. In this review, it discusses mechanisms that underlie acute and chronic dental pain. It details the measurement of somatosensory responses and pulpal blood flow as objective measures of tooth health and pain. It proposes that bridging these varied methodologies will significantly improve diagnosis and treatment of orofacial pain and pathology. It concludes that improving the precision of sensory measurements could yield important improvements in diagnostic challenges in pulpal pathology for noncommunicative and cognitively impaired individuals.

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.

Pulp and periradicular testing

Pulp and periradicular testing is crucial to the initial trauma evaluation and to subsequent monitoring of the traumatized teeth and supporting structures. An accurate diagnosis serves as the basis for therapeutic intervention and helps to ensure that destruction of the dental structures will be minimized and function will be regained. The purpose of this review is to present the current best evidence for accurate diagnostic testing of the pulp and periapex of traumatized teeth. Five databases were searched for literature pertaining to pulpal testing and trauma. Widely recognized textbooks were also consulted. Currently used pulp vitality testing is constrained by its subjective character and by the fact that it is a measure of neuronal status and not true pulpal viability. Tests that measure tissue perfusion more accurately reflect pulpal vitality, but they are not available commercially. This review discusses the specificity, sensitivity, and accuracy of commonly used tests, with emphasis on the applicability of certain tests to specific patient presentations in trauma. Factors that influence test selection are discussed, and specific recommendations are made on the basis of best evidence. Although differences exist between the various studies as to the accuracy of commonly used pulpal and periradicular tests, most of these have acceptable predictive value. Pulpal and periradicular tests in the trauma patient should be used in conjunction with clinical and radiographic observations to arrive at a diagnosis and treatment plan.

Doppler flowmetry as a tool of predictive, preventive and personalised dentistry

Periodontal lesions are considered a major problem in the global burden of oral diseases due to their high frequency and negative impact on quality of life. Periodontal inflammation is accomplished by a breakdown of microcirculatory function. Early detection of gingival microvessel dysfunction helps diagnose and prevent the progression of initial periodontal pathology. Doppler flowmetry is a useful tool in the diagnosis, monitoring, prognosis and management of periodontal patients which allows access not only of gingival blood flow but also of pulpal microcirculation. Doppler flowmeters might help to realise the ultimate target of predictive, preventive and personalised periodontology tailored with respect to the particular patient. This article highlights the main working principles of laser Doppler flowmeters and the ultrasonic Doppler flowmeters. The advances in blood flow measurement by ultrasonic flowmetry are discussed.

Pulpal blood flow changes in abutment teeth of removable partial dentures

The purpose of this study was to investigate the effect of tooth supported (TSD) and tooth-tissue supported (TTSD) removable partial denture wearing on pulpal blood flow (PBF) of the abutment teeth by using Laser Doppler Flowmeter (LDF). Measurements were carried out on 60 teeth of 28 patients (28 teeth and 12 patients of TTSD group, 32 teeth and 16 patients of TSD group) who had not worn any type of removable partial dentures before, had no systemic problems and were non smokers. PBF values were recorded by LDF before insertion (day 0) and after insertion of dentures at day 1, day 7 and day 30. Statistical analysis was performed by student t test and covariance analyses of repeated measurements. In the group TTSD, the mean values of PBF decreased statistically significantly at day 1 after insertion when compared with PBF values before insertion (p<0,01). There was no statistically significant difference among PBF mean values on 1st, 7th and 30th day. However, in the group TSD, there was no statistically significant difference among PBF mean values before insertion and on 1st, 7th and 30th day. In other words, PBF mean values in group TSD continued without changing statistically significant on 1st, 7th and 30th day.TTSD wearing may show negative effect on the abutment teeth due to decreasing basal PBF.

Assessment of pulp vitality: a review

BACKGROUND

One of the greatest diagnostic challenges in clinical practice is the accurate assessment of pulp status. This may be further complicated in paediatric dentistry where the practitioner is faced with a developing dentition, traumatized teeth, or young children who have a limited ability to recall a pain history for the tooth in question. A variety of pulp testing approaches exist, and there may be confusion as to their validity or appropriateness in different clinical situations.

AIM

The aim of this paper is to provide the clinician with a comprehensive review of current pulp testing methods. A key objective is to highlight the difference between sensitivity testing and vitality testing. A biological basis for pulp testing is also provided to allow greater insight into the interpretation of pulp testing results. The rationale for, and methods of, assessing pulpal blood flow are described.

Evaluation of Efficacy of a New Custom-Made Pulse Oximeter Dental Probe in Comparison With the Electrical and Thermal Tests for Assessing Pulp Vitality

Pulse oximetry is a noninvasive method of measuring vascular health by evaluating oxygen saturation. This study evaluated the efficacy of a new custom-made pulse oximeter dental probe in comparison with the electrical and thermal tests for assessing pulp vitality. Sensitivity, specificity, negative predictive value, and positive predictive value for each test were calculated by comparing the test results with the actual pulpal status, as evaluated by direct visual inspection. The sensitivity of the pulse oximeter was found to be 1.00, as compared to 0.81 with the cold test and 0.71 with the electrical test. The specificity of the pulse oximeter was 0.95, as compared to 0.92 with the cold and electrical pulp tests. Thus, the custom-made pulse oximeter dental probe is an effective, accurate, and objective method of evaluating pulp vitality.

Use of laser Doppler flowmetry to predict vitality of luxated or avulsed permanent teeth

OBJECTIVE

Splinting of traumatically displaced or avulsed permanent teeth has been described as an effective modality in the treatment of patients with dental injuries. The purpose of this study was to investigate whether laser Doppler flowmetry (LDF) measurements of pulpal blood flow (PBF) and/or dental injury type may predict treatment outcome of splinting of permanent maxillary incisors.

STUDY DESIGN

The study comprised 64 patients undergoing dental trauma splinting, who were characterized by the presence of a single permanent maxillary incisor affected by a subluxation, luxation, or avulsion type injury. Perfusion units (PU) were taken in 2 sessions, on the day of splint removal (6 weeks after trauma; session I) and 12 weeks after splint removal (session II). At each session, when an injured permanent maxillary central incisor was recorded, the respective contralateral homologous tooth was used as a control. An adverse outcome occurring 36 weeks after splint removal was defined as the presence of "periapical radiolucency and/or grey discoloration." A multiple logistic regression analysis was used to compute the odds ratio for session-related PBF characteristics and dental injury type for adverse outcome (n=22) versus nonadverse outcome (n=42).

RESULTS

There was a significant increase in PBF values from session I to session II (P=.047) for teeth without an adverse outcome, whereas teeth affected by an adverse outcome showed a significant decrease in PBF values (P=.001). PBF measurements did not change over time for the control group of contralateral incisors (P=.185). For the outcome criterion of "presence of periapical radiolucency and/or grey discoloration," there was a significant association between the treatment outcome groups and the variables of dental injury type (P=.049), session-related PBF difference (P=.000), and session II-related PBF level (P=.000). Significant increase in risk of an adverse outcome occurred with a session-related PBF difference (PBF(Session I) - PBF(Session II)) of >/=0 PU (8.6 odds ratio) (P=.014), and a session II-related PBF level of </=2.8 PU (20.2 odds ratio) (P=.030).

CONCLUSION

The data suggest the LDF test to be a valuable diagnostic adjunct for luxated teeth showing signs of adverse outcomes. Predictive modeling may provide clinicians with the opportunity to identify "at-risk" teeth early and initiate specific treatments.

Effect of gingiva on laser doppler pulpal blood flow measurements

The purpose of this study was to evaluate the effect of labial and palatinal gingiva on laser Doppler pulpal blood flow measurements. Twenty upper central incisor teeth determined to be vital from 20 volunteers were included into the study. To stabilize the probe, a laboratory-made acrylic splint positioned the probe labially on the cervical third of the tooth crown. We collected measurements without any gingival covering, and under three conditions: after application of an opaque paste on the labial gingiva, the palatal gingiva, or both the labial and palatal gingiva. The measurement values decreased 46% when there was opaque paste on labial gingiva, 10% on palatinal gingiva, and 63% on both. The decrease in the values when there was an opaque paste on palatinal gingiva was not statistically significant (p > 0.05). The differences between all other groups were statistically significant (p < 0.05). In these measurements, the contribution of labial gingiva to laser Doppler pulpal blood flow measurements is more than that of palatinal gingiva.

Assessing revascularization of avulsed permanent maxillary incisors by laser Doppler flowmetry

BACKGROUND

Laser Doppler flowmetry, or LDF, is a noninvasive method used to assess pulpal blood flow, or PBF. Dental avulsion is associated with loss of pulpal sensitivity. The authors conducted this study to assess whether LDF could be used to detect revascularization of replanted teeth.

METHODS

The authors used LDF to assess the PBF values of avulsed permanent maxillary incisors treated using replantation and splinting in 17 subjects. They took measurements at four sessions: on the day of splint removal and at 12 weeks, 24 weeks and 36 weeks after splint removal. Five vital control teeth and five nonvital control teeth were used to assess the background signal. At 36 weeks, the authors determined clinically and radiographically whether revascularization had occurred.

RESULTS

LDF readings correctly predicted the pulp status in 88.2 percent of the readings. Of the readings for vital teeth, 100 percent were correct, and of the readings for nonvital teeth, 80 percent were correct. Univariate analysis of variance demonstrated that in revascularized teeth, the PBF value increased significantly from splint removal to week 12 after splint removal and from week 24 to week 36 after splint removal. In the teeth that failed to revascularize, the PBF value dropped significantly from week 24 to week 36 after splint removal.

CONCLUSIONS

The results of this study suggest that LDF accurately diagnoses revascularization of avulsed maxillary incisors after replantation and splinting.

CLINICAL IMPLICATIONS

LDF may become useful in detecting revascularization much earlier than standard sensitivity tests.

The sources of laser Doppler blood-flow signals recorded from vital and root canal treated teeth

OBJECTIVES

The aim was to determine the strength of signals derived from the dental pulp and those from the surrounding tissues in human teeth using the laser Doppler flowmetry (LDF).

METHODS

Twenty-six vital teeth (13 experimental and 13 controls) from 12 patients were used. Experimental teeth had root canal treatment in a single visit and their healthy antimeres were controls. Blood flow measurements were made before and after local anaesthesia, after root canal preparation, following root canal filling and coronal restoration.

RESULTS

Perfusion unit (PU) values recorded from empty pulp chamber were determined to be only 30% lower than the values recorded before anaesthesia from the experimental intact teeth. When the measurements in the group were compared with each other the values of variation in the both groups were not statistically significant. The variation between the groups when the measurement values before anaesthesia, 10min after anaesthesia and after coronal restoration were compared, it was not statistically significant (P>0.05). The variation between the groups after preparation and root canal filling in their values of measurements was important statistically (P<0.05). The measurement values of the study group were lower than that of the control group.

CONCLUSIONS

In pulpal, LDF a major portion of the signal comes from tissues other than pulp. Without taking precautions (such as rubber-dam application) in pulp blood flow measurements, the results may be inconsistent.

Age-related changes in the human pulpal blood flow measured by laser Doppler flowmetry

The purpose of this study was to examine the age-related changes in human pulpal blood flow (PBF). Recordings were taken from 22 clinically healthy upper central incisors in 22 healthy participants (age: 8-75 years). A Moor blood flow monitor (type MBF3D) was used to measure PBF; and subjects' electrocardiogram (ECG), mean blood pressure (BP) and heart rate (HR) were also recorded. The resting PBF was significantly decreased with the increased age of the participants (Pearson's correlation coefficient, P < 0.001). The examined tooth crown was briefly(1 s) cooled using a dental coolant, and significant reductions in PBF were induced (one-way repeated measures anova, P < 0.05). The magnitude of the reduction (%) was significantly decreased with the increased age of the participants (Pearson's correlation coefficient, P < 0.05). The findings indicate that the hemodynamics in the human pulp is reduced with age.

The role of endodontics in the treatment of luxated permanent teeth

Pulp necrosis is a common complication following traumatic dental injuries and is related to the type and severity of the injury, as well as to the stage of development of the injured tooth. Endodontic intervention is required when there are clinical and radiographic signs of pulpal infection and its sequelae. Arrested tooth development with periradicular pathosis, external inflammatory root resorption, sinus tract formation and pain on percussion are indicative of root-canal infection in the post-traumatized teeth, and require immediate endodontic treatment. The use of calcium hydroxide in the treatment of teeth with post-traumatic pulp necrosis and its sequelae has been shown to be extremely beneficial for the long-term retention of the injured teeth. Calcium hydroxide has been shown to arrest and repair external inflammatory root resorptive defects, eliminate the endodontopathic microorganisms from the root canal system and induce hard-tissue barrier formation at the apex of non-vital immature teeth. This paper reviews the endodontic treatment required by post-traumatic non-vital permanent teeth.

Clinical management of the avulsed tooth: present strategies and future directions

The aim of this review article is to supplement the recently published International Association of Dental Traumatology (IADT) guidelines on treatment of the avulsed tooth. A thorough discussion on the reasoning behind each guideline is presented. In addition, the author's views on alternate treatment strategies and future directions, along with recent research on the subject of the avulsed tooth, are also presented.