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Notes: Abstract –  Laser Doppler flowmetry (LDF) is a non-invasive method to assess pulpal blood flow (PBF). Dental injury has been associated with significant PBF reduction. The purpose of this study was (i) to describe PBF characteristics of teeth with specific clinical outcomes, and (ii) to demonstrate diagnostic characteristics for different threshold PBF values for detection of specific multiple adverse outcomes. In 80 trauma patients, a single maxillary incisor treated by repositioning and splinting, and the respective contralateral homologous control tooth were investigated by LDF to assess local PBF values. Perfusion units (PU) were taken in two sessions, on the day of splint removal (session I), and 12 weeks after splint removal (session II). The ability of session II-related PBF measurements at 2.9, 6.4 and 9.9 PU levels to identify adverse outcomes occurring 36 weeks after splint removal was investigated. Adverse outcomes were classified as type I (loss of sensitivity), type II (periapical radiolucency), type III (grey discolouration), type IV (loss of sensitivity and periapical radiolucency), and type V (loss of sensitivity, periapical radiolucency and grey discolouration of crown). Receiver–operator characteristic (ROC) curves were used to evaluate the sensitivity and specificity of PBF assessments. There was a significant increase in PBF values from session I to session II (P = 0.0001) for teeth without an adverse outcome, while teeth affected by a type II–V outcome showed a significant decrease in PBF values (P 〈 0.05). PBF measurements did not change over time for the contralateral incisors (P 〉 0.05). A type IV and V outcome occurred in 21 and 24% of the instances, respectively. The PBF of 2.9 PU demonstrated a sensitivity of 70% and a specificity of 93% for type V outcomes. The best likelihood ratio was found for the PBF 2.9 PU level and incisors associated with a type V outcome. The data suggest that the LDF test to be a valuable diagnostic adjunct for luxated teeth showing signs of adverse outcomes including grey discolouration or a combination of other signs. However, it may also become necessary to apply clinical decision-making methods in order to correctly evaluate the value of information gathered. The clinical implication is that LDF may become useful in the prediction of adverse outcomes at a much earlier time period than may be accomplished by standard sensitivity tests.

Notes: summary  Laser Doppler flowmetry (LDF) is a non-invasive method to assess pulpal blood-flow (PBF). Dental injury has been associated with losses of pulpal sensibility. The purpose of this study was to assess the outcome of splint therapy on tooth fracture type-related PBF values. In 15 trauma patients, a single maxillary incisor treated by repositioning and splinting was investigated by LDF to assess local PBF values. Perfusion units were taken in four sessions, on the day of splint removel, and 12, 24 and 36 weeks after splint removal. Analysis of the tooth fracture type-related PBF measurements revealed root fractures to be associated with a significant decrease (P 〈 0·05) and uncomplicated crown fractures to be associated with a significant increase in PBF values (P 〈 0·05), while complicated crown fractures showed no significant difference between the session-related values (P 〉 0·05). The main findings of this study suggest splint therapy of root fractures of the central maxillary incisor to be associated with a short- and long-term decrease in PBF values. The LDF may become useful in the detection of transient ischaemic episodes and the identification of teeth at risk for adverse sequelae such as avascular necrosis and tissue loss.

Notes: summary The purpose of this study was to determine whether 12·5 MHz ultrasonography (US) could be used to assess the presence or absence of temporomandibular joint (TMJ) condylar osteoarthrosis. In 40 consecutive patients with TMJ disorders, 80 TMJs were investigated by US to analyse the condylar morphology. In order to compare the respective findings with those of a diagnostic method offering a high accuracy, coronal and sagittal magnetic resonance imaging was carried out immediately afterwards. With US showing a sensitivity of 87%, and a specificity of 20%, the data revealed US to be sensitive in detecting the presence, but insufficient in detecting the absence of osteoarthrosis. In addition, with a positive predictive value of 88%, and a negative predictive value of 18%, the results indicate that US may be valuable in diagnosing the presence, but insufficient in diagnosing the absence of osteoarthrosis. In view of the fact that the 12·5 MHz US technique proved to be a valuable diagnostic aid for the detection and prediction of abnormal condylar morphology, the results of this study should be of further interest and encourage research in its potential uses and diagnostic capabilities.

Notes: summary  Research is needed to assess the validity of the Clinical Diagnostic Criteria for Temporomandibular Disorders (CDC/TMD). The purpose of this study was to test the reliability of the clinical diagnosis of temporomandibular joint (TMJ) degenerative joint disease (DJD) as compared with the magnetic resonance imaging (MRI) ‘gold standard’. The TMJ DJD group comprised 48 joints in 24 consecutive patients who were assigned a clinical bilateral diagnosis of TMJ DJD. The TMJ non-DJD group consisted of 82 joints in 41 consecutive patients without a TMJ-related diagnosis of TMD. Bilateral sagittal and coronal MR images were obtained subsequently to establish the corresponding diagnosis of degenerative joint changes. An MRI diagnosis of osteoarthrosis (OA) was defined by the presence of flattening, subchondral sclerosis, surface irregularities, and erosion of the condyle or presence of condylar deformities associated with flattening, subchondral sclerosis, surface irregularities, erosion and osteophyte. For the CDC/TMD interpretations, the positive predictive of DJD for OA was 67%, and for the presence of degenerative joint changes 88%. The overall diagnostic agreement for DJD was 44·6% with a corresponding K-value of 0·01. Most of the disagreement was due to false-negative interpretations of asymptomatic joints. The results suggest CDC/TMD to be predictive for degenerative joint changes but insufficient for determination of OA. Patients assigned a clinical TMJ-related diagnosis of DJD may need to be supplemented by evidence from MRI to determine the presence or absence of OA.

Notes: summary  Laser Doppler flowmetry (LDF) is a non-invasive method to assess pulpal blood-flow (PBF). Dental injury has been associated with significant PBF reduction. The purpose of this study was to assess whether (i) the type of luxation trauma may affect PBF measurements and (ii) whether luxation type-related measurements may show short- and long-term changes of PBF values. In 41 trauma patients, 69 maxillary incisor treated by repositioning and splinting, and the respective contralateral homologous tooth were investigated by LDF to assess local PBF values. Perfusion units were recorded in four sessions, on the day of splint removal, and 12, 24 and 36 weeks after splint removal. Statistical analysis consisted of univariate analysis of variance for repeated measurements. For the LDF measurements, the main effect of the variable ‘session’ was not significant (P = 0·119). However, there was a significant ‘session’/‘luxation type’ interaction (P = 0·000). Analysis of simple session-within-luxation type effects revealed intrusive luxations to be associated with a significant decrease in PBF values (P = 0·000), while subluxations (P = 0·568), lateral luxations (P = 0·980), extrusive luxations (P = 0·910), and avulsions (P = 0·996) showed no significant difference between session-related values. The PBF measurements did not change over time for the contralateral incisors (P = 0·996). The LDF may become useful in the detection of pulpal ischaemic episodes in luxated maxillary incisors after repositioning and splinting. Further studies are warranted to assess the validity of the diagnosis of post-traumatic ‘ischaemic episodes’ by comparing it with histological tooth pulp changes, and by determining how well it may predict course and response to treatments in clinical trials.

Notes: summary The purpose of this study was to evaluate whether the magnetic resonance (MR) imaging variables of temporomandibular joint (TMJ) internal derangement, osteoarthrosis and/or effusion may predict the presence of pain in patients with a clinical disorder of an internal derangement type (ID)-III. The relationship between TMJ ID-III pain and TMJ internal derangement, osteoarthrosis and effusion was analysed in MR images of 84 TMJs in 42 patients with a clinical unilateral diagnosis of TMJ ID-III pain. Criteria for including a TMJ ID-III pain patient were report of orofacial pain referred to the TMJ, with the presence of unilateral TMJ pain during palpation, function and/or unassisted or assisted mandibular opening. Bilateral sagittal and coronal MR images were obtained to establish the presence or absence of TMJ internal derangement, osteoarthrosis and effusion. Using chi-square analysis for pair-wise comparison, the data showed a significant relationship between the MR imaging findings of TMJ ID-III pain and those of internal derangement (P=0·01) and effusion (P=0·00). Of the MR imaging variables considered simultaneously in the multiple logistic regression analysis, osteoarthrosis (P=0·82) and effusion (P=0·08) dropped out as non-significant in the diagnostic TMJ pain group when compared with the TMJ non-pain group. The odds ratio that a TMJ with an internal derangement type of disk displacement without reduction might belong to the pain group was strong (2·7:1) and highly significant (P=0·00). Significant increases in risk of TMJ pain occurred with ‘disk displacement without reduction in combination with osteoarthrosis’ (5·2:1) (P=0·00) and/or ‘disk displacement without reduction in combination with osteoarthrosis and effusion’ (6·6:1) (P=0·00). The results suggest that TMJ pain is related to internal derangement, osteoarthrosis and effusion. However, the data re-emphasize the aspect that these MR imaging variables may not be regarded as the unique and dominant factors in defining TMJ pain instances.

Notes: summary  Muscle thickness may now be measured in the clinic by ultrasonography. The purpose of this study was to test (i) whether the position of the transducer on the muscle affects muscle thickness measurements and (ii) whether measurements from identical locations vary over time. Muscle thickness of one masseter muscle side was measured in each of 30 volunteers. Measurements were recorded at five different locations on the lateral surface of each muscle. Four measurement sessions were performed, and two sets of measurements were recorded at each session. Spatial position of the transducer had a clear effect on the muscle thickness measurements (P 〈 0·0001). Measurements made at the most upper and middle level were less and greater (P 〈 0·0001), respectively, than those made at the upper, lower, and most lower levels. Measurements from various positions did not differ (P 〉 0·05) when made at the same level. Masseter thickness measurements recorded at a given site were consistent accross all of the testing sessions (P=0·575). The data suggest that reliable interpretation of longitudinal measurements of masseter thickness obtained with ultrasonography requires accurate repositioning of the transducer. Ultrasonography may be used to investigate the effect of specific treatment modalities on masseter thickness measurements.

Notes: summary  Laser Doppler flowmetry (LDF) is a non-invasive method to assess pulpal blood-flow (PBF). Dental luxation injuries have been associated with significant PBF reduction. The purpose of this study was to describe diagnostic characteristics for different session-related threshold PBF values for detection of specific adverse outcomes. In 61 trauma patients, a single maxillary incisor treated by repositioning and splinting, and the respective contralateral homologous control tooth were investigated by LDF to assess local PBF values. Perfusion units (PU) were taken 12 weeks (session I) and 24 weeks (session II) after splint removal. The ability of session I-related PBF measurements at 2·8, 6·4 and 10·1 PU levels, and of session II-related ameasurements at 2·4, 6·3 and 10·2 PU levels to identify adverse outcomes occurring 36 weeks after splint removal was investigated. Adverse outcomes were classified as type I (periapical radiolucency), type II (grey discoloration), and type III (periapical radiolucency and grey discoloration of crown). Receiver operator characteristic curves were used to evaluate the sensitivity and specificity of PBF assessments. There was no significant difference in PBF values between session I and session II (P 〉 0·05) for teeth without an adverse outcome, and those with a type I, II or III outcome (P 〉 0·05). The PBF measurements did not change over time for the contralateral incisors (P 〉 0·05). A type I, II and III outcome occurred in 36, 21 and 12% of the incisors, respectively. The best likelihood ratio was found for the PBF 6·4 PU level at session I and incisors associated with a type I (20·8) and type II outcome (15·2). The PBV of 6·4 PU demonstrated a sensitivity of 96% and a specificity of 59% for type I outcomes, and a sensitivity of 100% and a specificity of 50% for type II outcomes. The data suggest the LDF test to be a valuable diagnostic adjunct for luxated teeth showing signs of adverse outcomes.

Notes: summary  With the disadvantage of computed tomography showing cumulative biological effects and magnetic resonance imaging posing a problem in clinical availability and cost, several authors described the technique of ultrasonography to measure non-invasively local cross-sectional dimensions (LCSDs) of masseter muscle sites. However only few studies addressed the issue of ‘technique-related factors for intra- and inter-observer reliability’ to gain more consistent testing and diagnosis. The purpose of the present study was to determine (1) whether the scanning level and/or the muscle condition may affect LCSD measurements and (2) whether measurements made at identical levels may be reproducible. The study included 35 subjects with signs and symtoms of temporomandibular diorders. Bilateral ultrasonographic investigation was performed with a linear (B-scan) 7ḃ5 Mhz small-part transducer to register LCSDs of the anterior masseter muscle on three different levels. Scans were made on the relaxed and contracted muscle. Measurements were made in two sessions with a time interval of at least 5 min. Data were analysed for reproducibility by using the intra-class correlation coefficient (ICC) and the method error (ME). Scanning level and muscle condition had a significant effect on muscle measurements (P = 0ḃ000). There was no difference in LCSD between the right and left muscle (P = 0ḃ531). Measurements recorded at a given site were consistent across the testing sessions (P = 0ḃ058). The scanning level with highest reproducibility was halfway between the origin and insertion (ICC = 0ḃ92; ME = 6ḃ2%). The data suggest that ultrasonography is a reliable method for measuring LSCDs of the anterior masseter muscle.

Notes: Patients with temporomandibular disorders may present with a cluster of joint and muscle disorders characterized primarily by pain, joint sounds and irregular or deviating jaw function. Maxillary stabilization-type splints represent the best standard therapy, so the purpose of this study was to evaluate changes in local maximal clenching-related asymmetry patterns of masseter muscle sites associated with the immediate `application of splint therapy' using the diagnostic approach of high-resolution gray-scale ultrasonography. The study included 24 patients who had signs and symptoms of temporomandibular disorders. Ultrasonographic investigation was performed with a linear (B-scan) 7·5 Mhz small-part transducer to visualize the antero-superior, antero-inferior, medio-superior, medio-inferior, postero-superior, and postero-inferior sites of the masseter muscle. To assess local maximal clenching-related muscle asymmetry patterns and to evaluate the respective effect of occluding splints, the `absolute asymmetry index' was used, with the mean maximum muscle diameter of the respective right and left sides calculated from three consecutive measurements before and after splint insertion. Comparing the values assessed before splint insertion with those after splint insertion revealed a significant decrease in local maximal clenching-related muscle asymmetry values for the antero-inferior masseter muscle site (P 〈 0·05). The results of this study suggest stabilization-type splints to have a site-specific effect in the immediate reduction of local maximal clenching-related muscle asymmetries. Further studies are warranted to evaluate muscle-site specific effects in patient and non-patient groups and to relate these effects to pre-treatment variables like bite force, preferred chewing side, facial morphology and occlusion.