Comparison of laser fluorescence devices for detection of caries in primary teeth

The aim of this in vivo study was to evaluate the performance of fluorescence‐based devices in detecting occlusal caries lesions in primary molars compared with conventional methods. Two examiners assessed 44 occlusal surfaces of first and second primary molars in 20 patients using two fluorescence devices: DIAGNOdent (LF) and DIAGNOdent pen (LFpen). Teeth were also assessed by visual examination and bitewing radiograph. Histological examination served as the gold standard after extraction. By using the McNemar test, the sensitivity, specificity, accuracy, and area under the receiver operating curve were calculated as outer enamel (D1), inner enamel (D2) and dentine caries (D3) lesion thresholds. The intra‐ and inter‐examiner reproducibility were calculated using the Cohen's unweighted kappa statistics. At the D1 threshold, the LFpen sensitivity was statistically higher than LF and radiographic examination (P < 0.001), whereas there was no statistically significant difference among the groups at the D2 and D3 thresholds (P > 0.05). All methods demonstrated the highest sensitivity values at D3. At the D1 and D2 thresholds, there were no significant differences between the LFpen specificity and the other methods. All methods presented similar performance in detecting all lesions considering the area under the receiver operating curve. The LFpen showed better performance than LF. Furthermore, visual examination and the LFpen device seem to be sufficient for detection of occlusal caries in primary molars.     

Kaempferol Inhibits P. intermedia Lipopolysaccharide‐Induced Production of Nitric Oxide Through Translational Regulation in Murine Macrophages: Critical Role of Heme Oxygenase‐1‐Mediated ROS Reduction

Background: Nitric oxide (NO) could be a potential target for the development of new therapeutic approaches to the treatment of periodontal disease because this molecule plays a significant role in the tissue destruction observed in periodontitis. In this study, the authors investigate the effect of kaempferol on the production of NO by murine macrophage‐like RAW264.7 cells stimulated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen implicated in periodontal disease, and try to determine the underlying mechanisms of action. Methods: NO production was assayed by measuring the accumulation of nitrite in culture supernatants. Real‐time polymerase chain reaction was performed to quantify inducible NO synthase (iNOS) and heme oxygenase‐1 (HO‐1) mRNA expression. iNOS and HO‐1 protein expression and phosphorylation of c‐Jun N‐terminal kinase and p38 were characterized via immunoblot analysis. Reactive oxygen species (ROS) production was measured using the redox‐sensitive fluorescent probe 2′,7′‐dichlorodihydrofluorescein diacetate. Results: Kaempferol significantly inhibited NO production and expression of iNOS protein in P. intermedia LPS‐stimulated RAW246.7 cells without affecting iNOS mRNA expression. Kaempferol upregulated HO‐1 expression in LPS‐activated cells. Inhibition of HO‐1 activity by tin protoporphyrin IX (SnPP) abolished the suppressive effect of kaempferol on NO production. In addition, kaempferol significantly attenuated P. intermedia LPS‐induced increase of intracellular ROS, and SnPP blocked this reduction. Treatment with antioxidants downregulated the production of LPS‐induced NO. Conclusions: Kaempferol inhibits NO production and iNOS protein expression in P. intermedia LPS‐stimulated RAW264.7 cells at the translational level via HO‐1‐mediated ROS reduction and could be an efficient modulator of host response in the treatment of periodontal disease.     

Effects of Head and Neck Inclination on Bilateral Sternocleidomastoid EMG Activity in Healthy Subjects and in Patients with Myogenic Cranio-Cervical-Mandibular Dysfunction

This study was conducted in order to determine the effect of head and neck position on bilateral electromyographic (EMG) activity of the sternocleidomastoid muscles. The study was performed on 16 patients with myogenic cranio-cervical-mandibular dysfunction (CMD) and 16 healthy subjects. EMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the right and left sternocleidomastoid muscles. EMG activity was recorded in the left lateral decubitus position, in a darkened room and with the individual's eyes closed, under the following experimental conditions: 1. Head, neck, and body horizontally aligned; 2. Head and neck upwardly inclined with respect to the body, simulating the effect of a thick pillow, 3. Head and neck downwardly inclined with respect to the body, simulating the effect of a thin pillow. Variation of head and neck positions was determined by measuring the distance from the angle of neck and shoulder and the apex of the shoulder (SND = shoulder—neck distance) of each individual. Then, head and neck were forward or downwardly inclined with respect to the body at one-third of SND. A significantly higher contralateral EMG activity and a more asymmetric EMG activity were observed in the CMD group than in the healthy subjects (Kruskal-Wallis Test).These results suggest a different behavior of bilateral sternocleidomastoid EMG activity in CMD patients than in healthy subjects depending on the positioning of the head and neck.     

Osteomyelitis of the Mandible in a Patient with Osteopetrosis. Case Report and Review of the Literature

Osteopetrosis is a rare hereditary bone disorder presenting with variable clinical features and is characterized by an increase in bone density and reduction of marrow spaces that result from a defect in the function of osteoclasts and, consequently, a decrease in bone turnover. This disease is generally divided into three types: severe infantile malignant autosomal recessive, intermediate mild autosomal recessive, and benign autosomal dominant. The prognosis of the first two types is very poor and is characterized by an early onset, usually within the first decade of life, and early death. The benign-type is characterized by a later onset and a longer life span. Ten percent of osteopetrosis cases develop osteomyelitis that usually involves the mandible. The osteomyelitis is generally caused by tooth extraction or pulpal necrosis. The leading cause of the increased rate of infection is thought to be a lack of adequate bone vasculature. Treatment of osteomyelitis secondary to osteopetrosis is controversial. Treatment regimens include high-dose systemic antibiotics coupled with thorough debridement of necrotic bone and primary closure of soft tissues, if possible. Hyperbaric oxygen has been used for the treatment of chronic osteomyelitis.     

Preferences of AP position of the straight Caucasian facial profile

IntroductionSeveral investigators have compared the perception of profile attractiveness between professional and non-professional people, different groups of clinicians, and different ethnic groups. Our aim was to study preferences for facial protrusion in the lateral view for a straight Class I profile and to study the influence of gender, age, sex preference, and profession.Material and methodsPortrait images of one male and one female model with a Class I occlusal relationship were warped into nine different antero-posterior positions. An internet site was established to reach as many people as possible, and a request was sent by email to participate in a scientific experiment. Finally, 1707 Caucasion assessors could be grouped.ResultsThe preferred male profile is the straight full ante profile. For a feminine facial profile, the straight average and the straight 2/3 ante profiles were perceived as the most attractive. Surgeons tended to give significantly higher scores to attractive (ante) profiles, which correlated strongly with scores of the orthodontists.ConclusionWhenever possible with combined orthodontic/surgery treatment, straight ante profiles should be aimed for.     

Texture analysis of computed tomographic images in osteoporotic patients with sinus lift bone graft reconstruction

Objective

Bone implants are now widely used to replace missing teeth. Bone grafting (sinus lift) is a very useful way to increase the bone volume of the maxilla in patients with bone atrophy. There is a 6- to 9-month delay for the receiver grafted site to heal before the implants can be placed. Computed tomography is a useful method to measure the amount of remaining bone before implantation and to evaluate the quality of the receiver bone at the end of the healing period. Texture analysis is a non-invasive method useful to characterize bone microarchitecture on X-ray images.

Patients and methods

Ten patients in which a sinus lift surgery was necessary before implantation were analyzed in the present study. All had a bone reconstruction with a combination of a biomaterial (beta tricalcium phosphate) and autograft bone harvested at the chin. Computed tomographic images were obtained before grafting (t0), at mid-interval (t1, 4.2?±?0.7 months) and before implant placement (t2, 9.2?±?0.6 months). Texture analysis was done with the run-length method.

Results

A significant increase of texture parameters at t1 reflected a gain of homogeneity due to the graft and the beginning of bone remodeling. At t2, some parameters remained high and corresponded to the persistence of bone trabeculae while the resorption of biomaterials was identified by other parameters which tended to return to pregraft values.

Conclusion

Texture analysis identified changes during the healing of the receiver site.

Clinical relevance

The method is known to correlate with microarchitectural changes in bone and could be a useful approach to characterized osseointegrated grafts.     

A Simplified Palatal Lift Prosthesis for Neurogenic Velopharyngeal Incompetence

Velopharyngeal incompetence is a contributing factor to speech disorders and implies the presence of hypernasality, inappropriate nasal escape, and decreased air pressure during speech. One prosthetic treatment is a rehabilitative procedure employing a palatal lift prosthesis (PLP), which reduces hypernasality by approximating the incompetent soft palate to the posterior pharyngeal wall and consists of two parts, the anterior denture base and the palatal lifting plate, which are connected with steel wires; however, it seems difficult to reproduce the mobility of the soft palate in speaking, and it is therefore likely that the palatal lifting plate stimulates or oppresses the tissue of the soft palate and hinders rather than assists articulatory function. To avoid these disturbances we devised an adjustable PLP with a flexible conjunction between the denture base and the palatal lifting plate to obtain the optimal vertical lifting angle. The palatal plate was adapted to conform in a passive manner to the soft palate with light‐cured resin. The designed PLP simplified the procedure and reduced the number of adjustments and visits.     

Effects of different irrigation solutions on root dentine microhardness,smear layer removal and erosion

This study aimed to compare the effects of different irrigants on root dentine microhardness, erosion and smear layer removal. A total of 72 root dentine slices were divided into six groups, according to the final irrigants used: Group 1: 17% ethylenediamine tetra‐acetic acid (EDTA) + 2.5% NaOCl, Group 2: 7% maleic acid (MA) + 2.5% sodium hypochloride (NaOCl), Group 3: 1.3% NaOCl + mixture of tetracycline, acid and detergent (MTAD), Group 4: Smear Clear + 2.5% NaOCl, Group 5: 5% NaOCl, Group 6: saline. Vickers microhardness values were measured before and after treatment. In total, 42 root‐halves were prepared for scanning electron microscope to evaluate the amount of smear and erosion in the coronal, middle and apical thirds. Data were analysed using two‐way anova , Duncan and two‐proportion z‐tests. Maleic acid showed the greatest reduction in dentine microhardness (P < 0.05), followed by EDTA and MTAD. EDTA, maleic acid, MTAD and Smear Clear removed smear layer efficiently in the coronal and middle thirds of root canal. However, in the apical region, maleic acid showed more efficient removal of the smear layer than the other irrigants (P < 0.05).     

Regeneration of the periodontium using enamel matrix derivative in combination with an injectable bone cement

Objectives

Enamel matrix derivative (EMD) has proven to enhance periodontal regeneration; however, its effect is mainly restricted to the soft periodontal tissues. Therefore, to stimulate not only the soft tissues, but also the hard tissues, in this study EMD is combined with an injectable calcium phosphate cement (CaP; bone graft material). The aim was to evaluate histologically the healing of a macroporous CaP in combination with EMD.

Materials and methods

Intrabony, three-wall periodontal defects (2?×?2?×?1.7 mm) were created mesial of the first upper molar in 15 rats (30 defects). Defects were randomly treated according to one of the three following strategies: EMD, calcium phosphate cement and EMD, or left empty. The animals were killed after 12 weeks, and retrieved samples were processed for histology and histomorphometry.

Results

Empty defects showed a reparative type of healing without periodontal ligament or bone regeneration. As measured with on a histological grading scale for periodontal regeneration, the experimental groups (EMD and CaP/EMD) scored equally, both threefold higher compared with empty defects. However, most bone formation was measured in the CaP/EMD group; addition of CAP to EMD significantly enhanced bone formation with 50 % compared with EMD alone.

Conclusions

Within the limits of this animal study, the adjunctive use of EMD in combination with an injectable cement, although it did not affect epithelial downgrowth, appeared to be a promising treatment modality for regeneration of bone and ligament tissues in the periodontium.

Clinical relevance

The adjunctive use of EMD in combination with an injectable cement appears to be a promising treatment modality for regeneration of the bone and ligament tissues in the periodontium.     

Mechanical performance of encapsulated restorative glass-ionomer cements for use with Atraumatic Restorative Treatment (ART)

The Atraumatic Restorative Treatment (ART) approach was suggested to be a suitable method to treat enamel and dentine carious lesions in patients with disabilities. The use of a restorative glass-ionomer with optimal mechanical properties is, therefore, very important.

Objective:

To test the null-hypotheses that no difference in diametral tensile, compressive and flexural strengths exists between: (1) The EQUIA system and (2) The Chemfil Rock (encapsulated glass-ionomers; test materials) and the Fuji 9 Gold Label and the Ketac Molar Easymix (hand-mixed conventional glass-ionomers; control materials); (3) The EQUIA system and Chemfil Rock.

Material and Methods:

Specimens for testing flexural (n=240) and diametral tensile (n=80) strengths were prepared according to standardized specifications; the compressive strength (n=80) was measured using a tooth-model of a class II ART restoration. ANOVA and Tukey B tests were used to test for significant differences between dependent and independent variables.

Results:

The EQUIA system and Chemfil Rock had significantly higher mean scores for all the three strength variables than the Fuji 9 Gold Label and Ketac Molar Easymix (α=0.05). The EQUIA system had significant higher mean scores for diametral tensile and flexural strengths than the Chemfil Rock (α=0.05).

Conclusion:

The two encapsulated high-viscosity glass-ionomers had significantly higher test values for diametral tensile, flexural and compressive strengths than the commonly used hand-mixed high-viscosity glass-ionomers.