The effect of the dental follicle volume of palatally impacted canines on the relative position of the adjacent teeth.

OBJECTIVE: To assess if the dental follicle volume of palatally impacted canines (PICs) affects the relative root position of the adjacent lateral incisors (LIs) and first premolars (FPs). MATERIALS AND METHODS: A retrospective cross-sectional study of 49 patients with unilaterally PICs with dental follicles who had CBCT imaging previously taken. Four orthodontic centers in different countries provided the sample. A mean difference of 5° between the angular measurements (mesiodistal tip, buccolingual inclination, or mesiodistal rotation) of the LI and FP adjacent to the PIC and the controls was considered clinically relevant. A value of 0.05 was set for significance level and a power of 80%. The minimum sample size was determined to be 26 patients. These patients were further assigned to an LI sample (n = 49) and an FP sample (n = 23), dependent on the direct contact of the dental follicle to that adjacent tooth. A manual segmentation technique was used to obtain the volumetric measurements of the dental follicle. Angular measurements of adjacent teeth were then compared to the contralateral nonimpacted side, which acted as the control. A multivariant regression analysis was performed using IBM SPSS software, and statistical significance was set at α = 0.05. RESULTS: Adequate intra-rater reliability was accomplished. The multivariant regression analysis implied that there is no difference in the mean change in the tip, torque, and rotation of the LI and FP between the impacted and control sides when dental follicle volumes are considered (P = .509 for the LI sample and P = .804 for the FP sample). LIMITATIONS: CBCT imaging of dental follicle border delimitations, partial volume effect, and scattering are limitations. This is a convenience sample where the FP subsample is small. CONCLUSION: The dental follicle volume of the PICs does not seem to influence the relative position of the adjacent LI and FP mesiodistal tip, buccolingual inclination, and mesiodistal rotation. Early intervention could have been suggested to avoid certain malocclusion traits if significant displacements were demonstrated.

The labiopalatal impacted canine: Accurate diagnosis based on the position and size of adjacent teeth: A cone-beam computed tomography study.

INTRODUCTION: Labiopalatal impacted canines (L-PICs) occur when the canines lie between central and lateral incisors, with their tip palatal to the central incisor and part of their crown labial to the lateral incisor. Because of their unusual position, they are often misdiagnosed, and their orthodontic resolution fails. This study aims to provide clinicians with pathognomonic features for early and accurate positional diagnosis of L-PICs. METHODS: The L-PIC sample included 21 subjects with full diagnostic records. The control group of normally erupted canines was taken from a previous study. Clinical photographs, 2-dimensional radiographs, and cone-beam computed tomography were used to evaluate the positions of the adjacent incisors and first premolars, the canine incisor index, and the mesiodistal width of the lateral vs central incisors. RESULTS: Central incisors adjacent to L-PICs showed significant mesial root angulation, labial root inclination, and mesiolabial crown rotation, whereas lateral incisors presented significant distal root angulation, palatal root inclination, and mesiolabial crown rotation, in comparison to controls. The roots of the central and lateral incisors were divergent, in contrast to the controls, in which they were slightly convergent. The first premolar positions were not affected. The mean canine incisor index was significantly bigger in L-PICs vs the controls, suggesting a palatal canine. The lateral incisor widths were similar between the groups. CONCLUSIONS: This study provides the orthodontist with evidence-based clinical and radiographic red flags for diagnosing L-PIC, which may allow timely initiation of orthodontic treatment and correct planning of mechanotherapy.

Impaction of maxillary canines and its effect on the position of adjacent teeth and canine development: A cone-beam computed tomography study.

INTRODUCTION: The purposes of this study were to characterize the 3-dimensional position of teeth adjacent to impacted canines and examine whether impaction affects canine development using cone-beam computed tomography. METHODS: Cone-beam computed tomography images of 34 unilateral maxillary impacted canines (12 males, 22 females; mean age, 16.5 years) were collected. Twenty-one canines were palatally impacted (PIC), and 13 were buccally impacted (BIC). Angular measurements of lateral incisors (LIs), first premolars, and the impacted canines positions relative to a 3-dimensional coordinate system and canines' volume, length, and shape of the roots, were compared between the affected and contralateral control sides. The influence of canine position and severity of impaction was examined. Statistics included the paired t test, Wilcoxon signed rank test, and McNemar test. RESULTS: In the PIC group, LIs showed significant mesiobuccal rotation (-17.1°), mesial angulation (8.4°), and buccal root torque (5°) and first premolars mesiobuccal rotation (6.1°). In the BIC group, LIs displayed mesiobuccal rotation (-18°) and significant palatal root torque (-5°). The canine volumes were similar in BICs and slightly smaller in PICs. The lengths were shorter in both, but root hooks were more prevalent in BICs. The severity of impaction affected the measured variables. CONCLUSIONS: The differential position of the adjacent teeth is pathognomonic for PIC vs BIC, and impaction seems to affect canine development. The findings provide evidence-based clinical and radiographical clues for early diagnosis of canine displacement and planning the most efficient treatment strategy. In addition, they support timely orthodontic eruption before the development of the apical third of the root.

Validation of an ambulatory cough detection and counting application using voluntary cough under different conditions.

BACKGROUND: While cough is an important defence mechanism of the respiratory system, its chronic presence is bothersome and may indicate the presence of a serious disease. We hereby describe the validation process of a novel cough detection and counting technology (PulmoTrack-CC, KarmelSonix, Haifa, Israel). METHODS: Tracheal and chest wall sounds, ambient sounds and chest motion were digitally recorded, using the PulmoTrack(R) hardware, from healthy volunteers coughing voluntarily while (a) laying supine, (b) sitting, (c) sitting with strong ambient noise, (d) walking, and (e) climbing stairs, a total of 25 minutes per subject. The cough monitoring algorithm was applied to the recorded data to detect and count coughs.The detection algorithm first searches for cough 'candidates' by identifying loud sounds with a cough pattern, followed by a secondary verification process based on detection of specific characteristics of cough. The recorded data were independently and blindly evaluated by trained experts who listened to the sounds and visually reviewed them on a sonogram display.The validation process was based on two methods: (i) Referring to an expert consensus as gold standard, and comparing each cough detected by the algorithm to the expert marking, we marked True and False, positive and negative detections.These values were used to evaluate the specificity and sensitivity of the cough monitoring system. (ii) Counting the number of coughs in longer segments (t = 60 sec, n = 300) and plotting the cough count vs. the corresponding experts' count whereby the linear regression equation, the regression coefficient (R2) and the joint-distribution density Bland-Altman plots could be determined. RESULTS: Data were recorded from 12 volunteers undergoing the complete protocol. The overall Specificity for cough events was 94% and the Sensitivity was 96%, with similar values found for all conditions, except for the stair climbing stage where the Specificity was 87% with Sensitivity of 97%. The regression equation between the PulmoTrack-CC cough event counts and the Experts' determination was with R2 of 0.94. DISCUSSION: This validation scheme provides an objective and quantitative assessment method of a cough counting algorithm in a range of realistic situations that simulate ambulatory monitoring of cough. The ability to detect voluntary coughs under acoustically challenging ambient conditions may represent a useful step towards a clinically applicable automatic cough detector.