Growth patterns of the airway in Crouzon syndrome patients with different types of cranial vault suture synostosis

The severity of obstructive respiratory difficulty varies among affected Crouzon syndrome patients. The aim of this study was to investigate the correlation between the restricted airway volume in Crouzon syndrome and the associated type of cranial vault suture synostosis. Computed tomography scans of 68 unoperated Crouzon syndrome patients and 89 control subjects were subgrouped into four types: type I, bilateral coronal synostosis; type II, sagittal synostosis; type III, pansynostosis; type IV, perpendicular combinations of synostoses. Measurements were made using Mimics software. Of type I Crouzon patients, 42% had a restricted nasal airway (P = 0.002), while the pharyngeal airway volume was not significantly reduced. Type II Crouzon patients grew normal segmental airway volumes. Crouzon patients of type III developed simultaneously reduced nasal and pharyngeal airway volumes in infancy, by 38% (P = 0.034) and 51% (P = 0.014), respectively. However, the nasal airway achieved a normal volume by 2 years of age without any intervention, while the pharyngeal airway remained significantly reduced up to 6 years of age, by 42% (P = 0.013), compared to controls. Type IV Crouzon patients developed a reduced nasal airway volume (32%, P = 0.048) and a non-significant restricted pharyngeal airway (18%, P = 0.325). Airway compromise in Crouzon syndrome is variable when associated with different craniosynostosis fusion patterns. Type II (sagittal synostosis) Crouzon patients grew a normal nasopharyngeal airway volume. Those with types I (bicoronal synostosis) and IV (perpendicular synostoses) had significantly restricted nasal airways and a tendency towards a reduced pharyngeal volume. Type III (pansynostosis) Crouzon infants had the worst restriction of both airways, although there was some improvement with age.     

New method for quantification of the relative severity and (a)symmetry of isolated metopic synostosis

Trigonocephaly is the result of premature fusion of the metopic suture and its severity can vary widely. However, there is no gold standard for quantification of the severity. This study was performed to quantify severity using the Utrecht Cranial Shape Quantifier (UCSQ) and to assess forehead symmetry. Nineteen preoperative non-syndromic trigonocephaly patients (age ≤1 year) were included for the analysis of severity and symmetry. Severity according to the UCSQ was based on the following combined variables: forehead width and relative skull elongation. The UCSQ was compared to the most established quantification methods. A high correlation was found between the UCSQ and visual score (r = 0.71). Moderate to negligible correlation was found between the UCSQ and frontal angle, binocular distance, inter-ocular distance, and frontal stenosis. Additionally, correlation between the visual score and these established quantification methods was negligible. Assessment of the frontal peak (a)symmetry (ratio of right to left triangle area in the curve) showed a mean right versus left triangle area ratio of 1.4 (range 0.9–2.4). The results suggest that the UCSQ is appropriate for the quantification of severity based on the high correlation with clinical judgement. Furthermore, a larger triangle area right than left was unexpectedly found, indicating forehead asymmetry.     

“A comparative evaluation between single noncompression titanium miniplate and three dimensional titanium miniplate in treatment of mandibular angle fracture” – A randomized prospective study

PurposeThe aim of this study was to compare efficacy between the single non-compression titanium miniplate and single three-dimensional titanium miniplate in mandibular angle fracture treatment.Method and materialsA prospective study of 20 patients with mandibular angle fractures. Patients were randomly categorized into two groups with 10 patients in each group. Group-I patients were treated with single 2.0 mm conventional titanium miniplate, Group-II patients were treated with single 2.0 mm three-dimensional titanium miniplate according to Champy's principles. Parameters such as stability of fracture fragments, occlusion, mouth opening, additional fixation required and complications were evaluated at different time intervals.ResultsIn Group-I, about 40% (n = 4) of patients showed unstable fracture fragments on immediate postoperative day whereas in Group-II only 10% (n = 1) of patients with fracture instability. In Group-I, 30% (n = 3) had mild occlusal derangement and 20% (n = 2) had deranged occlusion on immediate postoperative day, where as in Group-II only 20% (n = 2) of patients had mild occlusal derangement. Additional fixation required in 30% (n = 3) of patients in group-I, and 10% (n = 1) in Group-II. 20% (n = 2) of patients in Group-I developed infection. All patients in both the groups had inadequate mouth opening on immediate post operative day, later resumed normal mouth opening. 10% (n = 1) in group-I and 20% (n = 2) of patients in group-II presented with postinjury/preoperative inferior alveolar nerve sensory disturbance with no incidence of postoperative sensory disturbance. None of the patients in both the groups had malunion, nonunion, plate fracture, and loosening of plates and screws.Conclusion3-D titanium miniplates showed more favorable results compared to single conventional titanium miniplate with respect to initial interfragmentary stability and complications.     

Prefabricated nerve conduits advance histomorphological and functional outcomes in nerve regeneration of the sciatic nerve of the rat

Bridging a nerve defect is sometimes necessary to achieve nerve regeneration after injury. Different methods and conduit designs have been considered, but only isograft transplants or prefabricated conduits are available. This study presents a comparison of prefabricated conduits and isograft transplants in rats, with the aim of making suggestions for clinical settings. In rats of inbred strains LEW and DA, a 1.5 cm defect of the sciatic nerve was reconstructed by isograft (n = 10) or conduit (n = 10). Untreated rats (n = 10), sham-operated rats (n = 10) and nerves of the non-operated contralateral limb served as controls. Regeneration was evaluated by histomorphological examination and with walking track analysis of the ankle stance angle (ASA) and the sciatic functional index (SFI). After 16 weeks, myelinization and ASA in the conduit group were significantly superior to that in the isograft group. There was no significant difference in SFI between the groups. Reconstruction in the isograft group showed a negative impact on the non-operated side. Conduits and isografts did not reach the morphological or functional levels of untreated or sham-operated animals. The results suggest preferential conduits should be used for nerve reconstruction.     

Photogrammetric evaluation of corrective surgery for trigonocephaly

The aim of this study was to capture preoperative, postoperative, and follow-up head shapes of male trigonocephaly patients who underwent fronto-orbital remodelling (FOR), using three-dimensional (3D) photography. Fifty-seven male infants with metopic synostosis operated on using standardized FOR during a 5-year period were included. All measurements were compared with those of an age-matched healthy control cohort (n = 253 for early postoperative comparison, n = 43 for the 1-year follow-up comparison) to determine the effect of FOR at 14 days and at 1 year post-surgery. Intracranial volume, frontal angle, nasofrontal angle, interfrontoparietal–interparietal ratio, and inter-orbital distances were measured 1 day preoperatively, 14 days and 1 year postoperatively. Mean age at surgery was 9.7 ± 1.1 months. Prior to surgery, boys with metopic synostosis showed a reduced intracranial volume (?7.0%, P < 0.001), frontal angle (?10.2%, P < 0.001), interfrontoparietal–interparietal ratio (?4.9%, P < 0.01), and orbital distances (?6.5%, P < 0.001) compared to the reference group, but values did not differ significantly from the specific control group after surgery (all P> 0.05). This was consistent by the time of the follow-up examination. Corrective surgery should therefore aim to achieve volume expansion and correction of the deformity. Furthermore, 3D photogrammetry provides a valuable alternative to computed tomography scans in the diagnosis of metopic synostosis, significantly reducing the amount of radiation exposure to the brain.     

Extracraniofacial anomalies in Treacher Collins syndrome: A multicentre study of 248 patients

Treacher Collins syndrome (TCS) is a congenital malformation of the craniofacial structures derived from the first and second pharyngeal arches. The craniofacial deformities are well described in the literature. However, little is known about whether there are associated extracraniofacial anomalies. A retrospective study was conducted using data from four craniofacial units. Medical charts were reviewed for the presence and type of extracraniofacial anomalies, as well as age at diagnosis. A possible correlation between the severity of the phenotype and the presence of extracraniofacial anomalies was assessed using the Hayashi classification. A total of 248 patients with TCS were identified; 240 were confirmed to have TCS, of whom 61 (25.4%) were diagnosed with one or more extracraniofacial anomalies. Ninety-five different extracraniofacial anomalies were found; vertebral (n = 32) and cardiac (n = 13) anomalies were most frequently seen, followed by reproductive system (n = 11), central nervous system (n = 7), and limb (n = 7) anomalies. No correlations between tracts were found. Extracraniofacial anomalies were more prevalent in these patients with TCS compared to the general population (25.4% vs 0.001–2%, respectively). Furthermore, a positive trend was seen between the severity of the syndrome and the presence of extracraniofacial anomalies. A full clinical examination should be performed on any new TCS patient to detect any extracraniofacial anomalies on first encounter with the craniofacial team.     

The normal evolution of the cranium in three dimensions

Insight into the growth and development of the normal newborn cranial shape is essential to monitor cranial development, to detect and diagnose abnormal skull shapes, and for the long-term follow-up of craniosynostosis surgery. The aim of this study was to analyse the growth pattern of the cranial shape of infants during the first years of life using 3D stereophotogrammetry and 3D computed tomography (CT) with advanced 3D evaluation techniques. A large set of 3D photographs (n = 199) and CT scans (n = 183), taken between ages 0 and 54 months, was collected. Cranial shapes with artefacts and asymmetries were removed. Total volumes and intracranial volumes were obtained, as well as 3D and 2D measurements, including the cranial width, cranial length, cranial index, and suture lengths. Growth maps were created for all modalities to indicate 3D growth over time. For the final analysis, a total of 130 3D photographs, 94 hard tissue CT scans, and 76 soft tissue CT scans were used. 3D and 2D measures, volumes, growth maps, and growth animations were obtained. A non-uniform growth was revealed by the 3D growth maps. This study addresses the need for normative cranial evolution data to monitor healthy cranial development and for detection, follow-up, and treatment planning in craniosynostosis.     

The efficacy of Salvadora persica extract in the elimination of the intracanal smear layer: A SEM study

AimTo evaluate the efficacy of an ethanolic Salvadora persica extract in removing the smear layer following a root canal procedure.MethodsSixty extracted, single-rooted human teeth were cleaned, shaped, and divided into four groups. Experimental groups 1 (n = 20) and 2 (n = 20) were irrigated with 1 mg/ml and 5 mg/ml of S. persica, respectively. The positive controls (n = 10) were irrigated with 17% ethylenediaminetetraacetic acid (EDTA), while the negative controls (n = 10) were irrigated with saline. Approximately 5 ml of the irrigating solution was delivered into the root canals for 5 min, and the final rinse was performed with 5 ml of 1% sodium hypochlorite. Scanning electron microscopy was used to evaluate the endodontic smear layer removal at the coronal, middle, and apical thirds of the specimens.ResultsA significant difference in smear layer removal between groups 1 and 2 at the coronal and middle thirds of the canal was observed, and no significant difference was seen between group 2 and the positive control at the coronal third. At the apical third, both concentrations of S. persica had similar effects and were less effective than the positive control in removing the smear layer.ConclusionThe 5 mg/ml S. persica solution was significantly more effective than the 1 mg/ml solution. In addition, the 5 mg/ml S. persica solution was as effective as 17% EDTA in removing the smear layer from the coronal third of the canal wall.     

Three-dimensional analysis of nasolabial soft tissue changes after Le Fort I osteotomy: a systematic review of the literature

A systematic review was conducted to investigate the three-dimensional (3D) effect of Le Fort I osteotomy on the nasolabial soft tissues. The literature search was conducted using the MEDLINE (accessed via PubMed), Embase, and Cochrane electronic databases until January 2018. A total of 333 studies were identified (PubMed, n = 292; Embase, n = 41; Cochrane Library, n = 0). Seventeen met the inclusion criteria. The studies were essentially retrospective. The risk of bias was considered high in 15 studies, medium in one study, and low in one study. 3D soft tissue analysis was performed at least 6 months after surgery (mean 8.3 months). The main image acquisition technique reported was cone beam computed tomography (CBCT), associated or not with 3D photography. Approximately 50% of the studies performed two-jaw surgery, 25% performed maxillary surgery only, and the other 25% included heterogeneous intervention groups. The most reported nasolabial changes were anterior and lateral movements of the nasomaxillary soft tissues and upper lip, together with anterior and superior movement of the nasal tip. The alar cinch suture and V–Y closure technique seemed to have little effect in counteracting the undesirable postoperative nasolabial changes. CBCT superimposition presented a reliable 3D assessment for simultaneous measurement of skeletal and soft tissue changes.     

Evaluation of the efficacy of celecoxib and ibuprofen on postoperative pain,swelling, and mouth opening after surgical removal of impacted third molars: a randomized,controlled clinical trial

The objective of this study was to compare the efficacy of celecoxib and ibuprofen in reducing postoperative sequelae following the surgical removal of impacted mandibular third molars. Ninety-eight subjects who needed surgical extraction of an impacted mandibular third molar were selected for the study. All subjects were randomly allocated to receive one of the following treatments twice a day for 5 days after surgery: placebo (n = 32), ibuprofen (n = 33), or celecoxib (n = 33). The primary outcome chosen was postoperative pain, which was evaluated using the visual analogue scale (VAS) score recorded by each patient. The secondary outcomes chosen were changes in postoperative swelling and maximum mouth opening values compared to preoperative ones. Compared to placebo, treatment with celecoxib and ibuprofen resulted in improvements in the primary outcome. Furthermore, when compared to the other groups, patients in the celecoxib group showed a significant reduction in postoperative pain scores at 6 h (P < 0.001), 12 h (P = 0.011), and 24 h (P = 0.041) after surgery. Regarding swelling and maximum mouth opening values, there were no significant differences between the groups at each follow-up session. This study demonstrated that treatment with celecoxib decreased the incidence and severity of postoperative pain following third molar surgery compared to ibuprofen and placebo.     

Quantification of tryptase-TIM-3 double-positive mast cells in human chronic periodontitis

ObjectivesMast cells (MCs) are implicated in the pathogenesis of allergic reactions and inflammatory conditions through the release of inflammatory mediators. So far limited attention has been given to the role of MCs in periodontitis. T cell immunoglobulin mucin domain (TIM)-3 is an immunomodulatory molecule and influences MC function. However, whether TIM-3 is expressed on MCs in the process of human periodontal disease has not been reported. Therefore, we identified MCs by toluidine blue staining and examined the expression of TIM-3 on tryptase-positive MCs in different severities of human chronic periodontitis using double-immunofluorescence staining in this study.Material and methodsA total of 83 human periodontal specimens were involved in this study, including healthy control tissues (n = 25), chronic moderate periodontitis (n = 28), and chronic severe periodontitis (n = 30). The gingival specimens were fixed in 10% buffered formalin, stained with haematoxylin and eosin for histopathology, with toluidine blue for MCs, and with double-immunofluorescence for identification of tryptase-TIM-3 double-positive MCs in gingival tissues.ResultsCompared with healthy controls, the score of gingival tissue inflammation was significantly increased in the chronic moderate periodontitis (P = 0.013) and chronic severe periodontitis (P < 0.0001), and the densities (cells/mm²) of tryptase-TIM-3 double-positive MCs were significantly increased in both the chronic moderate (P = 0.011) and severe periodontitis groups (P < 0.0001). However, compared with the chronic moderate periodontitis group, both the score of gingival tissue inflammation (P = 0.012) and the density of tryptase-TIM-3 double-positive MCs (P = 0.011) in gingival tissue were significantly increased in the severe periodontitis groups.ConclusionSignificantly increased number of tryptase-TIM-3 double-positive MCs had the similar tendency as the severity of periodontitis inflammation in human chronic periodontitis. Our data suggest that TIM-3 may have a role on MCs in human chronic periodontitis.     

Chimeric posterior tibial artery flap: clinical application in oral and maxillofacial reconstruction

The objective was to describe the utility of the chimeric posterior tibial artery flap (CPTAF) in the restoration of compound defects in the oral and maxillofacial region. Patients who underwent head and neck reconstruction using a CPTAF between February 2018 and February 2019 were included. Special consideration was given to the distribution of septocutaneous perforators (SPs), indications, flap survival, and complications. Nine patients were included. All flaps survived. One patient developed a surgical site infection, which was managed conservatively. The CPTAF was raised as a bipaddle skin flap without muscle (n = 1), with the gastrocnemius muscle (n = 6), or with the soleus muscle (n = 2). The number of SPs ranged from three to five (mean 4 ± 0.8). The SPs were mostly located between 4 cm and 20 cm proximal to the medial malleolus (mean 9.5 ± 3.8 cm). The skin paddle was used to reconstruct skin or mucosal defects, whereas the muscle part was used to fill the dead space (n = 7) or to support the orbital contents (n = 1). The donor site healed with no associated functional complications. The CPTAF is a good option for the restoration of composite tissue defects in the head and neck region. It offers flexibility during flap inset and provides the appropriate bulk to repair defects in multiple planes.     

A new approach in three dimensions to define pre- and intraoperative condyle–fossa relationships in orthognathic surgery – is there an effect of general anaesthesia on condylar position?

Incorrect registration of the condylar position in orthognathic surgery is supposed to cause postoperative relapse, condylar resorption and temporomandibular disorders. The aim of this prospective study was to evaluate the influence of general anaesthesia on centric relation (CR). Therefore, CR registered preoperatively in the awake patient and CR registered intraoperatively under general anaesthesia were recorded in 30 patients (14 men, 16 women) undergoing orthognathic surgery (skeletal class I: n = 3, II: n = 13, III: n = 14; symmetric: n = 20; asymmetric: n = 10). CR records were digitized and, through superimposition on the preoperative cone beam computed tomography of the patient's skull, the superior, anterior and posterior joint space and the volumetric congruence of 120 condyles were analysed. The linear measurements of joint spaces did not demonstrate any clinically relevant discrepancy between the CR measured in the awake and anaesthetized patient. In contrast, volumetric analysis revealed statistically significant differences between both states, with an intraoperative condylar sag predominantly in the posterior–inferior direction. The patient’s skeletal class or symmetry had no significant influence on the intraoperative condylar displacement. Thus, the risk of fixing the condyle in an unphysiological position supports the idea of using intraoperative condylar positioning devices to achieve predictable and stable outcomes.     

Camouflage treatment in skeletal Class III cases combined with severe crowding by extraction of four premolars

PurposeTo evaluate the changes in dentoskeletal structures and profile after extraction of four premolars in adult skeletal Class III borderline cases.Subjects and methodsThirteen Chinese patients (mean age was 22.0 ± 4.5 years) with skeletal Class III malocclusions and severe crowding in the upper arch were included in the study. These cases were diagnosed to be in the borderline surgical-orthodontic range but refused surgical treatments. All of them were treated by extraction of four premolars and standard edgewise technique. Lateral cephalometric radiographs taken at the start and end of treatment were analysed. Twenty-six cephalometric variables were calculated and paired t-tests were performed to assess the statistical significance of the treatment effects.ResultsNo significant changes were noted in the skeletal parameters (P ≥ 0.05). Regarding the dental parameters, the L1-MP angle decreased by 8.4°, the U1-L1 angle increased by 11.7° (P < 0.01), the L1-NB angle decreased by 10.1° and the L1-NB distance decreased by 5.2 mm (P < 0.01). The soft tissue parameters of Li-E, Li-H and Li-RL2 distance decreased by 3.3 mm, 3.3 mm and 4.5 mm, respectively (P < 0.01). All the patients finished with favorable occlusion and a straight profile.ConclusionsThe orthodontic camouflage by extraction of four premolars provides a viable treatment alternative for borderline skeletal Class III cases to achieve satisfying occlusal relationship and improve facial esthetics.     

Immediate dental and skeletal influence of distractor position on surgically assisted rapid palatal expansion with or without pterygomaxillary disjunction

The outcome of surgically assisted rapid palatal expansion (SARPE) can be affected by pterygomaxillary disjunction (PMD) and the distractor position. In this study, SARPE was performed, with or without PMD, in 20 fresh cadaver heads. Transverse expansion was conducted twice using a bone-borne distractor in the anterior and posterior positions, resulting in four groups (n = 10). Cone beam computed tomography scans were completed before and after SARPE to evaluate maxillary changes. A comparative anterior decrease and posterior increase in midpalatal opening resulted from SARPE with PMD combined with a posteriorly placed distractor. Significant differences in the internal transverse changes were found between the two SARPE techniques combined with an anterior distractor at the level of the premolars and molars for alveolar ridge width (P = 0.040, P = 0.024), and at the level of the molars for the dental crown width (P = 0.017) and corresponding tooth cusp width (P = 0.018). In contrast, using a posteriorly placed distractor led to a significant difference for tooth cusp width only (P = 0.050). No statistically significant differences were found between external transverse changes or between distractor positions. PMD is more important in achieving a more uniform and parallel transverse expansion pattern than the distractor position. However, a posterior distractor seems to intensify the effects of PMD.     

Decreased postoperative pain after reduction of fractured nasal bones using a nerve block of the anterior ethmoidal nerve

There is consensus that all patients should experience minimal pain following reduction of a fractured nasal bone. The issue requiring further study is what technique will provide patients with the greatest pain relief following the reduction of nasal fractures. This study investigated the use of an anterior ethmoidal nerve block as preemptive analgesia for the management of postoperative pain associated with reduction of nasal bone fractures. The medical documents of 85 patients were reviewed for a retrospective case-controlled comparative study. Patients in the nerve block group (n = 45) were injected with 2% lidocaine containing epinephrine into the anterior ethmoidal nerve and dorsal periosteum, and those in the control group (n = 40) were not. The rate of patients requiring postoperative injectable analgesics was compared between the two groups. The rate of patients who received a postoperative analgesic injection was significantly lower in the nerve block group than in the control group (P = 0.034). The use of an anterior ethmoidal nerve block and dorsal periosteal injection of anaesthetic solution during reduction of fractured nasal bones under general anaesthesia resulted in the effective reduction of postoperative pain. Thus, this is regarded as a good method for enhancing patient quality of care and compliance in the reduction of fractured nasal bones.     

Racial disparity of Crouzon syndrome in maxilla and mandible

The racial disparity of facial features in craniosynostosis patients is not fully understood. The aim of this study was to explore the difference in maxillary and mandibular morphology and spatial position in Asian and Caucasian Crouzon syndrome patients. Ninety-one computed tomography scans were included (12 Asian Crouzon syndrome patients, 22 Asian controls; 16 Caucasian Crouzon syndrome patients, 41 Caucasian controls) and measured using Materialise software. The maxillary and mandibular volumes of Asian patients were both reduced by 19% (P = 0.102 and P = 0.187), and those of Caucasian patients were reduced by 15% (P = 0.142) and 14% (P = 0.211) when compared to the respective race-specific controls. Maxilla length of Asian patients was reduced by 6.36 mm (14%, P = 0.003), while the reduction in Caucasian patients was 4.88 mm (10%, P = 0.038). ANS was retracted 11.99 mm (P < 0.001) in Asian patients and 11.54 mm (P < 0.001) in Caucasian patients. The ANB angle was narrowed by 13.17° (P < 0.001) in Asian patients compared to Asian controls, and by 7.02° (P < 0.001) in Caucasian patients compared to Caucasian controls. The retrusive midface profiles of Asian and Caucasian Crouzon syndrome look similar; both result from the combined effect of hypoplastic size and backward displacement. However, the insufficiency was found to be more a failure of the anteroposterior maxillary length in Asian patients, and more due to posterior maxillary positioning in Caucasian patients. Therefore, prognathism in Crouzon syndrome patients is more likely caused by displacement rather than elongation of mandibular length in both races. Crouzon syndrome results in the same extent of overall volume deficiency of the maxilla and mandible in these races.     

Healing masseter entheses of mandibular reconstruction with autograft—Raman spectroscopic and histological study

Autogenous bone graft represents the gold standard for mandibular reconstruction. The authors used a beagle mandibular defect model and reconstructed with iliac crest and ulna graft. Healing masseter entheses were harvested 24 weeks after surgery and analyzed by histology and Raman microspectroscopy. The intensity ratio of 960/2940 was to document mineral-to-collagen ratio as degree of mineralization. Pearson correlation was used to evaluate the association between the intensity ratios of 960/2940 and the tendon-to-bone insertion site. In the normal control group (n = 4) and the experimental control group with detached masseter muscle (n = 4), the degree of mineralization at the insertion site increased linearly from tendon to bone. In the iliac graft (n = 4) and ulna graft groups (n = 4), healing entheses were far less mature than controls and a linear trend was not observed. There was no significant correlation between degree of mineralization and insertion site in the ulna group (r_spearman = 0.519, P > 0.001). These results indicate that transplanted bone plays a critical role in healing of entheses and healing enthesis to reconstructed mandible is inferior to normal. Raman spectroscopy provides quantitative information about different healing entheses and gives valuable insight into mechanical properties of entheses in functional mandibular reconstruction.     

Effects of myogenous facial pain on muscle activity of head and neck

This study evaluated the effects of visual input on surface electromyography (sEMG) of some stomathognatic and neck muscles (anterior temporalis, masseter, anterior digastric and sternocleidomastoid muscles) in patients experiencing myogenous facial pain compared with healthy volunteers. All subjects kept the mandible at rest with teeth apart and underwent a 15-s sEMG recording of anterior temporalis, masseter, digastric and sternocleidomastoid muscles. Each recording was carried out with closed and then open eyes. The sEMG activity of each muscle was compared between the two groups. In the study group, anterior temporalis, masseter and sternocleidomastoid sEMG with closed eyes showed higher values compared with controls (p < 0.05). In the study group, left and right anterior temporalis (p < 0.003) and right digastric (p < 0.03) sEMG with open eyes showed higher values than sEMG with closed eyes. In the control group no significant differences were observed between closed and open eyes. In patients with myogenous facial pain, visual input appears to be associated with a significant increase in the sEMG activity of some head and neck muscles.     

Middle mesial canals in mandibular first molars: A micro-CT study in different populations

ObjectiveTo describe the morphological aspects of middle mesial canals (MMC) in mandibular first molars using micro-CT.DesignMandibular first molars collected from the Brazilian (n = 136) and Turkish (n = 122) populations were scanned (voxel size: 9.9 μm) and mesial roots with MMC (n = 48) evaluated regarding several morphological aspects. The incidence of MMC in each population was statistically compared using Chi-square test (α = 0.05).ResultsOverall, the incidence of MMC was 18.6% (48 out of 258 molars) and was significantly higher in the Brazilian (n = 30; 22.1%) than in the Turkish (n = 18; 14.8%) population (p < 0.05). In both populations, confluent configuration of the MMC was the most frequent anatomy. Most of the specimens with MMC had 3 independent orifices (n = 26; 54.2%) and 3 apical foramina (n = 21; 43.8%). The mean minor diameter of the MMC orifice (0.16 mm) was 3 times less than the other orifices (∼0.50 mm). In mesial roots with independent configuration (n = 3; 6.3%), the mean volumes (mm³) of the MMC, mesiobuccal (MBC) and mesiolingual (MLC) canals were 0.20 ± 0.10, 0.75 ± 0.28, and 0.88 ± 0.19, respectively. In the specimens with canal confluence (n = 26; 54.2%), MMC merged to the MBC (n = 8; 16.7%), MLC (n = 4; 8.3%), or to both MBC and MLC (n = 14; 29.2%). Double mesial canal was observed in only 1 specimen. MMC with an independent foramen was observed mostly in Brazilian specimens.ConclusionsIncidence of MMC was higher in the Brazilian molars. Confluent configuration was the most prevalent anatomic variation, while independent and fin configurations, as well as, double MMC, were found only in a few specimens.