Dental bitewing radiographs segmentation using deep learning-based convolutional neural network algorithms

OBJECTIVES

Dental radiographs, particularly bitewing radiographs, are widely used in dental diagnosis and treatment Dental image segmentation is difficult for various reasons, such as intricate structures, low contrast, noise, roughness, and unclear borders, resulting in poor image quality. Recent developments in deep learning models have improved performance in analyzing dental images. In this research, our primary objective is to determine the most effective segmentation technique for bitewing radiographs based on different metrics: accuracy, training time, and the number of training parameters as a reflection of architectural cost.

METHODS

In this research, we employ several deep learning models, namely Resnet-18, Resnet-50, Xception, Inception Resnet v2, and Mobilenetv2, to segment bitewing radiographs. The process begins by importing the radiographs into MATLAB®(MathWorks Inc), where the images are first improved, then segmented using the graph cut method based on regions to produce a binary mask that distinguishes the background from the original X-ray.

RESULTS

The deep learning models were trained on 298 and 99 radiograph training and validation sets and were evaluated using 99 images from the testing set. We also compare the segmentation model using several criteria, including accuracy, speed, and size, to determine which network is superior. Furthermore, we compare our findings with prior research to provide a comprehensive understanding of the advancements made in dental image segmentation. The accurate segmentation achieved was 93.67% and 94.42% by the Resnet-18 and Resnet-50 models, respectively.

CONCLUSION

This research advances dental image analysis and facilitates more accurate diagnoses and treatment planning by determining the best segmentation technique. The outcomes of this study can guide researchers and practitioners in selecting appropriate segmentation methods for practical dental image analysis.

The scientific management of deep carious lesions in vital teeth using contemporary materials—A narrative review

Aim

The aim of this article is to review the scientific evidence for deep caries removal in permanent vital teeth and the choice of dentine replacement material and restoration of the teeth to maintain long term tooth vitality and function.

Method

The two position statements namely the European Society of Endodontology and the American Association of Endodontists position statements on vital pulp therapy will be scrutinized and compared with regards to the deep caries removal strategy and assessed for evidence of best practice. The properties of materials used to manage vital pulps and the best way to restore the teeth will be reviewed and guidance on the full management of vital teeth will be suggested.

Conclusions

Promoting new treatment modalities for reversible and irreversible pulpitis allowing for pulp preservation should be considered. Although debatable, cases with deep caries should be managed by complete non-selective caries removal which will allow for pulpal management if needed and a more predictable outcome can be expected when using the new materials and treatment modalities of vital pulp therapy.

Blue Light Laser Results in Less Vocal Fold Scarring Compared to KTP Laser in Normal Rat Vocal Folds

OBJECTIVES

Preliminary investigations suggest that a novel blue light (BL) laser with a wavelength of 445 nm is comparable to the commonly utilized potassium titanyl phosphate (KTP) laser (532 nm) for treatment of various laryngeal pathologies. The objective of the current study is to make a direct histological comparison of the degree of vocal fold scarring after either BL or KTP laser treatment in an animal model.

STUDY DESIGN

This was a randomized controlled study using rats.

METHODS

Twenty-four Sprague-Dawley rats were randomized to BL or KTP laser treatment. Laser was delivered in non-overlapping pulses to normal rat vocal folds. Larynges in each group were harvested at three time points: post-operative day 1, 30, and 90. Three animals served as negative controls. The excised whole larynges were sectioned transversely and stained with hematoxylin/eosin and trichrome. Presence of subepithelial inflammation and protein deposition/fibrosis indicative of scarring were scored semi-quantitatively (from grade 1-3) by two pathologists blinded to treatment groups.

RESULTS

Between-group comparison showed that both laser treatments resulted in significantly elevated subepithelial protein deposition/fibrosis 90 days after treatment compared to negative controls (BL: 2 ± 0; KTP: 2.67 ± 0.29; control: 1.17 ± 0.29; P < .05). However, the degree of protein deposition/fibrosis was significantly higher in the KTP group compared to the BL group (P = .016). Within-group comparison showed that the KTP group showed evidence of fibrosis as early as 30 days after treatment, which was not observed in the BL group.

CONCLUSIONS

The current study suggests that the degree of scarring is significantly less after BL laser treatment compared to KTP in normal rat vocal fold tissue.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:853-858, 2021.

Continuous glucose monitoring, oral glucose tolerance, and insulin - glucose parameters in adolescents with simple obesity

In obese adolescents pancreatic beta-cells may not be able to cope with insulin resistance leading to hyperglycemia and type2 diabetes (T2DM To assess oral glucose tolerance, 72-h continuous blood glucose concentrations (CGM) and calculate homeostatic model assessment (HOMA), and the quantitative insulin sensitivity check index (QUICKI) in 13 adolescents with simple obesity (BMI SDS=4 ± 1.06). OGTT performed in 13 obese adolescents (13.47 ± 3 years) revealed 3 cases (23%) with impaired fasting glucose (IFG: fasting glucose >5.6 mmol/L), 4 cases (30%) with impaired glucose tolerance (IGT: 2h blood glucose >7.8 <11.1 mmol/L), and none with diabetes. Using the continuous glucose monitoring system ( CGMS), IFG was detected in 4 cases, the maximum serum blood glucose (BG : 2h or more after meal) was >7.8 and <11.1 mmol/L (IGT) in 9 children (69%) and >11.1 mmol/L (diabetes) in one case (7.6%). Five cases had a minimum BG recorded of <2.7 mmol/L (hypoglycemia). No glycemic abnormality was detected using HbA1C (5.7 ± 0.3%). 11/13 patients had HOMA values >2.6 and QUICKI values <0.35 denoting insulin resistance. Beta cell mass percent (B %) = 200 ± 94.8% and insulin sensitivity values (IS)=50.4 ± 45.5% denoted insulin resistance with hyper-insulinaemia and preserved beta cell mass. In obese adolescents, CGMS is superior to OGTT and HbA1C in detecting glycemic abnormalities, which appears to be secondary to insulin resistance.

Root canal debridement efficacy of different final irrigation protocols

AIM

To compare the smear layer and debris removal effectiveness of four root canal irrigation protocols as well as their effectiveness in removing remaining soft tissues in curved root canals.

METHODOLOGY

The mesiobuccal and mesial root canals of 107 extracted human maxillary and mandibular molars were instrumented using Mtwo rotary NiTi instruments then randomly divided into four groups according to a final rinse protocol: Group 1 (n = 28) - manual agitation of 1% NaOCl and 15% EDTA; Group 2 (n = 26) - CanalBrush agitation of 1% NaOCl and 15% EDTA; Group 3 (n = 26) - 3% H(2) O(2) alternated with 1% NaOCl; Group 4 (n = 27) - passive ultrasonic agitation of 1% NaOCl and 15% EDTA. All irrigation protocols were performed in a closed system. Eleven roots per group were prepared and histologically stained (H&E) to assess percentage of remaining pulpal tissues in the apical thirds. The remaining specimens were split longitudinally and examined under scanning electron microscope at ×2000 magnification to assess smear layer and debris removal. Image Pro Plus 6.0 software was used to analyse smear layer and remaining pulp tissue. Debris presence was scored by two blinded investigators using a five-point scale. Data were analysed using Univariate analysis of variance (GenStat 13, α = 0.05).

RESULTS

CanalBrush and passive ultrasonic irrigation were equally effective with significantly less smear layer and debris than manual agitation and H(2) O(2) alternated with NaOCl (P < 0.05). The H(2) O(2) alternated with NaOCl protocol was significantly more effective in removing pulp tissue remnants in the apical level than manual agitation (P = 0.009) and passive ultrasonic irrigation (P = 0.01).

CONCLUSIONS

CanalBrush was as effective as passive ultrasonic irrigation in smear layer and debris removal. Alternating H(2) O(2) with NaOCl was effective in removing soft tissues from root canal complexities. Further studies are required to evaluate effectiveness of this regimen taking into account irrigant volume differences and effect of root canal system configuration.

Long-term outcome after admission for acute severe ulcerative colitis in Oxford: the 1992-1993 cohort

BACKGROUND

To determine the long-term outcome of patients admitted with acute severe colitis (ASC) who avoided colectomy on the index admission, a retrospective cohort study was performed.

METHODS

Patients admitted for intensive treatment of ASC in 1992-1993 previously described for a predictive index of short-term outcome in severe ulcerative colitis (UC) were followed for a median 122 months (range 3-144). Complete responders (CR) to intensive therapy had <3 nonbloody stools/day on day 7 of the index admission; incomplete responders (IR) were all others who avoided colectomy on that admission. Main outcome measures were colectomy-free survival, time to colectomy, and duration of steroid-free remission.

RESULTS

In all, 6/19 CR (32%) came to colectomy compared to 10/13 IR (P = 0.016; relative risk 3.33, 95% confidence interval [CI] 1.12-9.9). The median +/- interquartile range time to colectomy was 28 +/- 47 months (range 6-99) for CR who came to colectomy versus 7.5 +/- 32 (3-72) months for IR (P = 0.118). Among the IR, 7/13 came to colectomy within 12 months, and all within 6 years from the index admission. The longest period of steroid-free remission was 42 +/- 48 (0-120) months for CR, but 9 +/- 20 (1-35) months for IR (P = 0.011).

CONCLUSIONS

One week after admission with ASC in the prebiologic era, IRs had a 50% chance of colectomy within a year and 70% within 5 years, despite cyclosporin and azathioprine where appropriate. The maximum duration of remission in CRs was almost 5 times longer than IRs. It is unknown whether biologics change the long-term outcome.

High prevalence of vitamin D deficiency in young children in a highly sunny humid country: a global health problem

AIM

Several studies indicate a high prevalence of vitamin D deficiency among young populations. Information about the vitamin D status in young adult populations from the Middle East is scarce. The vitamin D status can be expected to be influenced by highly different factors between various countries in Europe, the Middle East and Asia. The aim of this study was to determine the prevalence of vitamin D deficiency in young Qatari children below 16 years of age.

METHODS

A cross-sectional study carried out among children below 16 years of age who visited the Primary Health Care Centers (PHCs). The survey was conducted over a period from August 2007 to March 2008. Qatari nationals, male and female, aged below 16 years. A random sample of 650 children who visited the PHC Centers was approached and parents of 458 children expressed their consent to participate in this study, corresponding to a response rate of 70.5%. Face-to-face interviews were based on a questionnaire that included variables such as socio-demographic information, life style, family history and feeding patterns during infancy, and clinical information as well as laboratory investigations for biochemical assessment of vitamin D status.

RESULTS

Of the total number of 458 children surveyed, 228 (49.8%) were males and 230 (50.2%) females. The prevalence of vitamin D deficiency among the studied Qatari children was (68.8%), mostly in the age group (11-16) years (61.6%). There was a significant difference between vitamin D deficient and normal children as compared to their age (P=0.013). Vitamin D deficiency was more common among girls (51.4%) than boys (48.6%). Exposure to sunlight was limited in both groups; but even lower in vitamin D deficient children (57.5%) than in normal children (70.6%). The duration of time spent outside was again low in both groups but significantly lower in vitamin D deficient children (23.5 minutes) compared to normal children (28.4 minutes). Low duration of time spent outdoors, breast feeding less than 6 months, a family history of diabetes mellitus and physical activity were significant predictors for vitamin D deficiency in Qatari children. Rickets, fractures, gastroenteritis and delayed milestones were all significantly higher in vitamin D deficient children.

CONCLUSIONS

The present study revealed that the prevalence of vitamin D deficiency is high in Qatari children and more common in Qatari girls. In the young population in Qatar, vitamin D deficiency appears to result from a combination of limitations in sunlight exposure and a low oral intake of vitamin D.

Recurrent acute liver failure and mitochondriopathy in a case of Wolcott-Rallison syndrome

A 10-year-old Arabic boy of consanguineous parents has suffered eight episodes of acute liver failure with haemolysis triggered by intercurrent febrile illnesses. The first crisis occurred at 9 months of age, after which diabetes mellitus developed. By the age of 6 years, short stature, mild myopathy and later skeletal epiphyseal dysplasia also became evident. His psychosocial development and educational achievements have remained within normal limits. While there were no clear biochemical indicators of a mitochondrial disorder, an almost complete deficiency of complex I of the respiratory chain was demonstrated in liver but not in fibroblast or muscle samples. Molecular analysis of the eukaryotic translation initiation factor 2alpha kinase gene (EIF2AK3) demonstrated a homozygous mutation, compatible with a diagnosis of Wolcott-Rallison syndrome (WRS). This patient's course adds a new perspective to the presentation of WRS caused by mutations in the EIF2AK3 gene linking it to mitochondrial disorders: recoverable and recurrent acute liver failure. The findings also illustrate the diagnostic difficulty of mitochondrial disease as it cannot be excluded by muscle or skin biopsy in patients presenting with liver disease. The case also further complicates the decision-making process for liver transplantation in cases of acute liver failure in the context of a possible mitochondrial disorder. Such patients may be more likely to recover spontaneously if a mitochondrial disorder underlies the liver failure, yet without neurological features liver transplantation remains an option.

High prevalence and level of resistance to metronidazole, but lack of resistance to other antimicrobials in Helicobacter pylori, isolated from a multiracial population in Kuwait

BACKGROUND

The primary treatment regimen for Helicobacter pylori infection for Kuwaitis does not contain metronidazole, but that for expatriates does. There is also increasing failure of antimicrobial therapy.

AIM

To determine the susceptibility of H. pylori from upper gastrointestinal biopsies of Kuwaitis and non-Kuwaitis to find out if differences existed in the susceptibilities of the isolates from the two different populations.

METHODS

The susceptibilities of 96 H. pylori isolates were tested against metronidazole, amoxicillin, clarithromycin and tetracycline by the E test. The rdxA gene was analysed from selected metronidazole-susceptible and metronidazole-resistant strains to find out polymorphism and the basis of metronidazole resistance.

RESULTS

Approximately, 70% of isolates from both populations were metronidazole resistant with 65% isolates showing high minimum inhibitory concentration values of >256 mug/mL. No resistance to the other three antimicrobials was found. There were novel nonsense and missense mutations with no deletion in the rdxA gene by insertion of mini-IS605.

CONCLUSIONS

The prevalence and level of metronidazole resistance in H. pylori in the two populations was high with no difference, in spite of different treatment regimens. Metronidazole resistance in this transitional country appeared to be independent of prior metronidazole use for treatment of H. pylori infection.

Serum sodium changes during and after transuretheral prostatectomy

OBJECTIVE

This prospective study aims at determining the effect of transurethral resection of the prostate on serum sodium levels during and after the procedure.

METHODS

One hundred consecutive unselected patients with prostatic obstructive symptoms over a period of 11 months underwent transurethral resection of the prostate using continuous flow irrigation with 1.5% glycine running from a height of 70 cm above the table level under epidural anesthesia and were given 1L of intravenous normal saline/hour during the procedure. Resection time ranged between 25 and 90 minutes (mean 32) and was less than 45 minutes in 91 patients (91%). No postoperative irrigation or diuretics were given and the patients were given food and liberal fluids immediately after the operation.

RESULTS

Fifty-four patients (54%) had intraoperative reduction of serum sodium ranging between 2 and 7 mmol/L (mean 3.5), 18 of whom showed further drop of 2-10 mmol/L after 24 hours (mean 3.4). Twenty-five patients (25%) did not have any intraoperative change in their serum sodium level, 6 of whom dropped their serum sodium 24 hours later. After 24 hours, 41 patients (41%) ended with serum sodium lower than their preoperative level by 2-12 mmol/L (mean 4%), 3 of whom had a drop of 10-12 mmol/L. The reduction was manifested 24 hours after the procedure in 27 patients (27%). None of the patients had transurethral resection syndrome nor its prodromal manifestations.

CONCLUSION

After transurethral resection of the prostate, hyponatremia can occur as late as 24 hours postoperatively. Short operative time, giving intravenous sodium supplement intraoperatively and avoiding postoperative irrigation were perhaps factors in avoiding drastic hyponatremia and transurethral resection syndrome in this prospective series of unselected patients.

Johanson's staged urethroplasty revisited in the salvage treatment of 68 complex urethral stricture patients: presentation of total urethroplasty

BACKGROUND

To show our experience with the staged Johanson's urethroplasty as a salvage treatment of difficult and complicated groups of patients, and to present the total urethroplasty technique.

MATERIAL AND METHODS

During a 12-year period, 68 men with urethral stricture underwent the staged Johanson's urethroplasty. 51 had war-related injuries (75%) resulting in an unhealthy perineal and genital skin with fistulae and/or scarring. 35 patients (52%) had other urethral or vesical problems. 60 patients (88%) had long (0.5-4 cm), multiple or impassable strictures. 58 patients (85%) had strictures of the pendulous urethra. The second stage was performed 2-3 months after the first. Both stages of Johanson's urethroplasty were protected by a stab suprapubic catheter for 3 weeks. Patients were followed up for 23-82 months (mean 52.5).

RESULTS

All patients but 4 had improved urine flow (best Qmax ranged between 13.2 and 31.8 ml/s; mean 17.4). 4 patients (6%) needed a revision because of fistula formation or recurrence and 6 patients (9%) developed urinary tract infection postoperatively.

CONCLUSIONS

The staged Johanson's urethroplasty is a good treatment for the difficult and complicated urethral strictures which are not suitable for optical urethrotomy, especially those in the pendulous part. In strictures involving all parts of the urethra total urethroplasty could be performed.

Role of B7-CD28/CTLA-4 costimulation and NF-kappa B in allergen-induced T cell chemotaxis by IL-16 and RANTES

The mechanisms that cause T cell recruitment into inflamed airways of asthmatic individuals are poorly understood. It has been shown previously that both natural exposure to allergen and challenge in the laboratory induce T cell accumulation in the bronchial mucosa of sensitized asthmatics. To study the mechanisms involved in this process, we have used an explant model in which bronchial biopsies taken from mild atopic asthmatic volunteers during fiberoptic bronchoscopy were stimulated in culture for 24 h by the common aeroallergen house dust mite (Dermatophagoides pteronyssinus (Der p)). Analysis of culture supernatants showed that stimulation with Der p significantly enhanced both the generation of T cell chemotactic activity by the mucosal tissue, as assayed in microchemotaxis chambers, and the production of IL-16 and RANTES. Neutralization experiments showed that IL-16 contributed more to the chemotactic activity than RANTES. The fusion protein CTLA-4-Ig, blocking B7:CD28 costimulation, and dexamethasone both significantly reduced the ex vivo production of chemotactic activity and release of IL-16 and RANTES. The proteasome inhibitor Cbz-Ile-Glu(OtBu)-Ala-leucinal also had a significant inhibitory effect on T cell chemotactic activity and IL-16 but not RANTES generation, indicating a role for nuclear factor NF kappa B activation. These results indicate that allergen stimulates cells within the bronchial mucosa to increase IL-16 and RANTES release, both of which contribute to T cell accumulation in asthmatic airways. The allergen-induced chemotactic activity is dependent on cell activation via CD28 and involves, at least partly, NF-kappa B.

Phenoxybenzamine in the management of neuropathic bladder following spinal cord injury

BACKGROUND

The present study aims to show the clinical and urodynamic effects of phenoxybenzamine on the neuropathic bladder of spinal cord-injured patients who failed to be free of catheter by attaining satisfactory voiding function, despite initial bladder training.

METHODS

Forty-six spinal cord-injured patients were subjected to pharmacological manipulation with phenoxybenzamine. It was used as an adjunct in the management of neuropathic bladder dysfunction that caused failure of the bladder to empty, by tapping or crede to achieve satisfactory residual urine volume of < 100 mL. Phenoxybenzamine was started with a dose of 10 mg daily, increased by 10 mg every 3 days to a dose of 30 mg daily; this was maintained from 3 weeks to 6 months (mean: 39 days). The pre-treatment residual urine volume ranged between 100 and 1050 mL (mean: 360 mL). Follow-up periods ranged between 12 and 36 months (mean: 16 months).

RESULTS

Five patients (11%) were excluded due to either inadequate treatment or inadequate follow-up. Nineteen patients (41%) with reflex (upper motor neurone) bladders showed improvement of bladder evacuation. There was a reduction of the maximum urethral closure pressure, which ranged between 10 and 32 cm of water (mean: 22 cm). Twenty-two patients (48%) did not respond, requiring other measures to be taken which included transurethral surgery (n = 19). Nine of the failures involved areflex (lower motor neurone) bladders, and seven failures involved reflex bladders with an extremely tight outlet and urethral closure pressure of > 50 cm of water. Six failures involved reflex bladders that were lacking strong enough detrusor contractions to attain a balanced bladder responsive to abdominal tapping; response was achieved by administration of a parasympatheticomimetic drug. Neuropathic bladders with uninhibited detrusor contractions responded well to phenoxybenzamine.

CONCLUSIONS

Phenoxybenzamine proved useful in reducing bladder outlet resistance after spinal cord injury, provided that detrusor bladder contractions were present. It is useful in controlling detrusor-sphincter dyssynergia and autonomic hyperreflexia. It was not useful in areflex bladders, perhaps due to the development of spasticity of the striated muscle component of the external sphincter. The presence of bladder neck (internal sphincter) dysfunction may modify or abolish its effect.

RNA-protein interactions within the 3 ' untranslated region of vimentin mRNA

Several functions have been attributed to protein binding within the 3'untranslated region (3'UTR) of mRNA, including mRNA localization, stability, and translational repression. Vimentin is an intermediate filament protein whose 3'untranslated sequence is highly conserved between species. In order to identify sequences that might play a role in vimentin mRNA function, we synthesized32P-labeled RNA from different regions of vimentin's 3'UTR and assayed for protein binding with HeLa extracts using band shift assays. Sequences required for binding are contained within a region 61-114 nucleotides downstream of the stop codon, a region which is highly conserved from Xenopus to man. As judged by competition assays, binding is specific. Solution probing studies of 32P-labeled RNA with various nucleases and lead support a complex stem and loop structure for this region. Finally, UV cross-linking of the RNA-protein complex identifies an RNA binding protein of 46 kDa. Fractionation of a HeLa extract on a sizing column suggests that in addition to the 46 kDa protein, larger complexes containing additional protein(s) can be identified. Vimentin mRNA has been shown to be localized to the perinuclear region of the cytoplasm, possibly at sites of intermediate filament assembly. To date, all sequences required for localization of various mRNAs have been confined to the 3'UTR. Therefore, we hypothesize that this region and associated protein(s) might be important for vimentin mRNA function such as in localization.

A 10 year review of the endoscopic treatment of 125 spinal cord injured patients with vesical outlet obstruction: does bladder neck dyssynergia exist?

The management of 125 patients with post-traumatic neuropathic bladder and vesical outlet obstruction is described and a policy of endoscopic treatment is suggested. A total of 1652 spinal cord injured patients were treated during the period of 1983-1992. About 8% had an outlet of obstruction which required endoscopic treatment. The outcome of transurethral resection of the external sphincter and/or bladder neck was retrospectively analyzed in 82 patients, and a prospective study was conducted on the other 43 patients. We have demonstrated that patients with a complete spinal cord lesion at any level, and those with a high incomplete lesion (above T-9) have benefited from external sphincterotomy combined with bladder neck resection. We emphasize that patients with a low incomplete lesion (T-9 and below) have benefited from bladder neck resection alone. Bladder neck (internal sphincter) obstruction or dyssynergia may require to be considered in the management of the neuropathic bladder.