-
The Journal of Prosthetic Dentistry Aug 2022Three-dimensional (3D) additive manufacturing (AM) is an evolving technology in dentistry, proposed as an alternative to subtractive milling manufacture (MM) or... (Review)
Review
STATEMENT OF PROBLEM
Three-dimensional (3D) additive manufacturing (AM) is an evolving technology in dentistry, proposed as an alternative to subtractive milling manufacture (MM) or conventional processing. However, a systematic review of the use of AM technology instead of milling or conventional processing is lacking.
PURPOSE
The purpose of this systematic review and meta-analysis was to evaluate the mechanical properties of 3D-printed prosthetic materials compared with MM and conventional techniques.
MATERIAL AND METHODS
An electronic search of the literature was conducted on the MEDLINE (via PubMed), Scopus, and Web of Science databases. The inclusion criteria were in vitro studies published in the last 5 years, in English or Italian, and with 3D AM printed dental prosthetic materials. Data extraction was focused on dental prosthetic materials (ceramics, polymers, and metals) and their mechanical properties: flexural strength, fracture load, hardness, roughness, removable partial denture (RPD) fit accuracy, trueness, marginal discrepancy, and internal fit. Data considered homogenous were subjected to meta-analysis using the Stata17 statistical software program (95% confidence interval [CI]; α=.05). Since all variables were continuous, the Hedge g measure was calculated. A fixed-effects model was used for I=0%, while the statistical analysis was conducted using a random-effects model with I>0%.
RESULTS
From a total of 3624 articles, 2855 studies were selected, and 76 studies included after full-text reading. The roughness of AM-printed ceramics generally increased compared with that of conventional processing while the marginal discrepancy was comparable both for ceramics and polymers. The flexural strength, hardness, and fracture load of AM-printed polymers were statistically lower than those of the conventional group (P<.05). No significant difference was detected in terms of hardness, roughness, marginal discrepancy, fracture load, trueness, or internal fit between the AM and MM techniques (P>.05). Milling techniques showed significantly higher values of flexural strength (Hedge g=-3.88; 95% CI, -7.20 to -0.58; P=.02), also after aging (Hedge g=-3.29; 95% CI, -6.41 to -0.17; P=.04), compared with AM printing.
CONCLUSIONS
AM is comparable with MM in terms of mechanical properties, in particular with polymeric materials. The flexural strength of AM-printed prostheses is lower than with conventional and MM techniques, as are the parameters of hardness and fracture load, while the marginal discrepancy is similar to that of MM and conventional techniques. AM prostheses are commonly used for interim crowns and fixed partial dentures, as their rigidity and fracture resistance cannot support mastication forces for extended periods. More comparative studies are needed.
PubMed: 35934576
DOI: 10.1016/j.prosdent.2022.06.008 -
European Spine Journal : Official... Oct 2022There are conflicting opinions regarding the efficacy of chewing gum for the recovery of gastrointestinal function in patients following spinal surgery. Thus, we aimed... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
There are conflicting opinions regarding the efficacy of chewing gum for the recovery of gastrointestinal function in patients following spinal surgery. Thus, we aimed to conduct a systematic review and meta-analysis of existing articles to evaluate the effect of gum-chewing on patients following spinal surgery.
METHODS
A computer search was used to identify randomised controlled trials (RCTs) involving gum-chewing from eight databases: Cochrane Library, PubMed, Embase, MEDLINE, Web of Science, China National Knowledge Infrastructure, China Science and Technology Journal Database, and WanFang Data. After evaluating the risk of bias for the included studies, we used the Revman 5.3 software to conduct a meta-analysis of the data.
RESULTS
The study included seven RCTs, with a total of 706 patients. The meta-analysis reported that gum-chewing could shorten the interval between surgery and first bowel movement (mean deviation [MD] = - 23.02; 95% confidence interval [CI]: - 24.67, - 21.38; P < 0.00001), first flatus (MD = - 1.54; 95% CI - 2.48, - 0.60; P = 0.001), and first bowel sounds (MD = - 5.08; 95% CI - 6.02, - 4.15; P < 0.00001). Moreover, there was a significant reduction in postoperative analgesic dosage within 12 h (standardised mean difference [SMD] = - 0.28; 95% CI - 0.52, - 0.05; P = 0.02). However, there were no significant differences between the chewing gum and control groups (P > 0.05) regarding the postoperative nausea score, abdominal pain score, 24- and 48-h analgesic drug dosage, and length of hospital stay.
CONCLUSION
To a certain extent, masticating gum can promote the recovery of gastrointestinal function and reduce the need for postoperative analgesics in patients following spinal surgery. However, this conclusion is affected by the quantity and quality of the included articles. Therefore, additional high-quality studies are needed to verify these results.
Topics: Abdomen; Chewing Gum; Humans; Length of Stay; Postoperative Complications; Postoperative Period
PubMed: 35852608
DOI: 10.1007/s00586-022-07304-w -
Critical Reviews in Food Science and... Nov 2023The study aimed to evaluate the hypothesis that chewing is a mechanical and physiological contributor to swallowing, physiologic/pathologic processes of the...
The study aimed to evaluate the hypothesis that chewing is a mechanical and physiological contributor to swallowing, physiologic/pathologic processes of the gastrointestinal tract (GIT), and nutrition-related factors. A search strategy was applied to three different databases to investigate if chewing function in adults affects the swallowing, physiologic/pathologic processes of the GIT, and nutrition-related factors compared to controls with no exposure. The included studies were evaluated for methodological quality and risk of bias and certainty of evidence. The results showed 71 eligible studies. Overall, the results showed that 46 studies supported the hypothesis while 25 refuted it. However, the GRADE analysis showed low to very low certainty of the evidence to support the hypothesis that chewing is an important contributor in the swallowing process, and physiologic/pathologic processes in the GIT. The GRADE analysis also showed a moderate to very low certainty of the evidence to suggest that chewing function contributes to nutrition-related parameters. The overall results of the current study showed that a majority (64.7%) of the studies (46 out of 71) supported the hypothesis. However, robust studies with proper design, adequate sample size, and well-defined outcome parameters are needed to establish conclusive evidence.
Topics: Deglutition; Mastication; Gastrointestinal Tract; Nutritional Status
PubMed: 35837677
DOI: 10.1080/10408398.2022.2098245 -
Journal of Dentistry Aug 2022To give an overview of the current evidence on the associations of general health conditions with masticatory performance and maximum bite force in older adults. (Review)
Review
OBJECTIVES
To give an overview of the current evidence on the associations of general health conditions with masticatory performance and maximum bite force in older adults.
DATA/SOURCES
Three electronic databases (Medline via PubMed, Embase via Ovid and CINAHL Plus via EBSCOhost) were searched up to September 2021 for cross-sectional studies on general health conditions and masticatory performance or maximum bite force in older adults. Methodological quality of the included studies was independently evaluated based on Joanna Briggs Institute critical appraisal checklist for analytical cross-sectional studies. Data on the associations between general health conditions and masticatory performance or maximum bite force were extracted.
STUDY SELECTION
Of the 5133 records identified, 39 studies (43 articles) were included in this review. Significant negative associations were found between masticatory performance and stroke, sarcopenia, amyotrophic lateral sclerosis, chronic obstructive pulmonary disease, dyspepsia, dysphagia, anorexia, and carotid atherosclerosis. Significant negative association was found between maximum bite force and sarcopenia. There were equivocal results on the association between masticatory performance and diabetes mellitus, and between maximum bite force and stroke, and amyotrophic lateral sclerosis. There was no significant association between masticatory performance and metabolic syndrome, and between maximum bite force and progress of Parkinson's disease. Most studies revealed positive associations of physical function with masticatory performance and maximum bite force.
CONCLUSIONS
Negative associations between masticatory function of older adults and presence of several systemic diseases have been reported in a number of studies while there are positive associations between masticatory function and some physical function indicators.
CLINICAL SIGNIFICANCE
This study provides valuable information on the association of masticatory function with general health, which draws clinicians' attention to the masticatory function of older adults who suffer from certain systemic diseases or physical dysfunction, and to the need to improve their masticatory ability to achieve healthy aging.
Topics: Aged; Amyotrophic Lateral Sclerosis; Bite Force; Cross-Sectional Studies; Humans; Mastication; Sarcopenia; Stroke
PubMed: 35691453
DOI: 10.1016/j.jdent.2022.104186 -
Acta Odontologica Scandinavica Jan 2023The aims of this systematic review were to evaluate the clinical masticatory performance of implant-supported restorations, observe the occlusal force changes in the... (Review)
Review
OBJECTIVE
The aims of this systematic review were to evaluate the clinical masticatory performance of implant-supported restorations, observe the occlusal force changes in the distribution of the implant restoration and reveal the positive and negative contributing factors of implant design and components based on the outcomes of digital occlusal measurement.
MATERIAL AND METHODS
An extensive search was conducted through PubMed and CENTRAL to identify clinical trials on implant-retained restorations using digital occlusal analysis methods. Two researchers assessed the identified studies and data extraction independently, and the data synthesis strategies without meta-analysis that summarizes the effect estimates were adopted.
RESULTS
The search screened 3821 titles and abstracts, then full-text analysis for 26 articles was performed, and 14 studies were included in the quantitative synthesis. Four of six studies for implant-retained overdenture showed statistically significant improved bite force when immediate loading ( = .00045, .00005, .00055, and .00005, respectively), and no statistically significant results in the other two studies ( = .225, .371, respectively.) However, the results of the favoured intervention were not statistically significant ( = .104, .166, respectively) in two studies of single posterior implant restorations. In all three studies, the bite force distributed on the implant prostheses of partially fixed implant-retained restoration increased statistically significantly ( = .013, .001, .05, respectively).
CONCLUSIONS
The edentulous restoration supported by implants seems to significantly improves bite force and chewing efficiency compared with conventional dentures. Regular quantitative occlusal measurement is recommended to avoid the possible risk of overload. Smaller implants size and relatively small and flexible attachment designs may be more conducive to the stability and retention of the restoration of atrophy of alveolar bone.
Topics: Humans; Dental Implants; Dental Prosthesis, Implant-Supported; Bite Force; Dentures; Mouth, Edentulous
PubMed: 35617455
DOI: 10.1080/00016357.2022.2077980 -
European Journal of Pediatrics May 2022Patients who undergo salivary gland, neck, or facelift surgery or suffer from diabetes mellitus often develop Frey syndrome (also known as auriculotemporal syndrome or...
Patients who undergo salivary gland, neck, or facelift surgery or suffer from diabetes mellitus often develop Frey syndrome (also known as auriculotemporal syndrome or gustatory sweating). Frey syndrome has been occasionally reported to occur in subjects without history of surgery or diabetes but this variant of Frey syndrome has not been systematically investigated. We searched for original articles of Frey syndrome unrelated to surgery or diabetes without date and language restriction. Article selection and data extraction were performed in duplicate. Our systematic review included 76 reports describing 121 individual cases (67 males and 54 females) of Frey syndrome not associated with surgery or diabetes. The age at onset of symptoms was ≤ 18 years in 113 (93%) cases. The time to diagnosis was 12 months or more in 55 (45%) cases. On the other hand, an allergy evaluation was performed in half of the cases. A possible cause for Frey syndrome was detected in 85 (70%) cases, most frequently history of forceps birth (N = 63; 52%). The majority of the remaining 22 cases occurred after a blunt face trauma, following an auriculotemporal nerve neuritis or in association with a neurocutaneous syndrome. The cause underlying Frey syndrome was unknown in 36 cases. Conclusion: Frey syndrome not associated with surgery or diabetes almost exclusively affects subjects in pediatric age and is uncommon and underrecognized. Most cases occur after forceps birth. There is a need to expand awareness of this pseudo-allergic reaction among pediatricians and allergists. What is Known: • Pre-auricular reddening, sweating, and warmth in response to mastication or a salivary stimulus characterize Frey syndrome. • It usually occurs after salivary gland surgery and in diabetes. What is New: • In children, Frey syndrome is rare, and most cases occur after a forceps-assisted birth. • In childhood, this condition is often erroneously attributed to food allergy.
Topics: Child; Diabetes Mellitus; Female; Food Hypersensitivity; Humans; Male; Neck; Sweating, Gustatory
PubMed: 35182195
DOI: 10.1007/s00431-022-04415-w -
PloS One 2022Khat is a flowering plant with stimulant effect on the nervous system and produce psychological dependence. Despite its harmful effects, the ingestion of khat has been...
INTRODUCTION
Khat is a flowering plant with stimulant effect on the nervous system and produce psychological dependence. Despite its harmful effects, the ingestion of khat has been part of cultural norms and the legality of khat varies by region.
OBJECTIVE
This systematic review aimed at critically evaluating the available evidence on the risk factors of khat chewing among adolescents.
METHODS
A systematic review was conducted on published research studies from five databases Scopus, PubMed, Science-direct, Ovid and google scholar using keywords khat chewing OR qat chewing AND associated factors OR risk factors OR contributing factors AND adolescents OR teenagers. Articles included were either cross-sectional, cohort, case-control or qualitative studies which were published between the year 1990 till present. Excluded articles were the non-English written articles, descriptive studies and irrelevant topics being studied.
RESULTS
Out of 2617 records identified and screened, six were included for the analysis and interpretation of the data. All included studies were cross-sectional study design. All six studies reported having family members who chewed khat significantly predict khat chewing among adolescents, followed by five articles for friends or peers who also chewed khat and four articles for male gender. Smoking was also found to have the highest odds (OR = 18.2; 95% CI: 12.95-25.72) for khat chewing among adolescents.
CONCLUSION
The review highlights the crucial role of family members, friends or peers and male gender to predict khat chewing among adolescents. Effectiveness of health promotion programs to educate and reduce khat chewing among adolescents will require active participation of family members and friends.
Topics: Adolescent; Africa; Catha; Central Nervous System Stimulants; Cross-Sectional Studies; Female; Friends; Humans; Male; Mastication; Risk Factors; Students; Substance-Related Disorders
PubMed: 35113927
DOI: 10.1371/journal.pone.0263372 -
Journal of Oral Rehabilitation Apr 2022Bite is an important function of the human stomatognathic system. Despite this, it is commonly impaired in temporomandibular disorder (TMD) populations. The aim of this... (Review)
Review
BACKGROUND
Bite is an important function of the human stomatognathic system. Despite this, it is commonly impaired in temporomandibular disorder (TMD) populations. The aim of this review is to evaluate the effectiveness of conservative interventions on self-reported and physical measures of bite function in individuals with TMD.
METHODS
This review was performed in compliance with PRISMA guidelines. An electronic search was performed on databases including PubMed, CINAHL, Embase, and Cochrane Central. Inclusion criteria were journal articles evaluating the effect of any non-pharmacological conservative interventions on bite function in participants diagnosed with TMD. Risk of bias for individual studies was assessed using the Cochrane risk-of-bias v2 tool, and the NIH NHLBI pre-post tool. Data was synthesised based on outcome measures of bite function, and the quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach.
RESULTS
Eleven studies were eligible for this review. Interventions included splinting, photobiomodulation, needling, exercise, manual therapy, and patient education, which were evaluated using mastication-related pain, self-reported chewing difficulty, and bite force/endurance outcome measures. Findings suggested manual therapy, needling, oral splinting, exercise, and PBM interventions may improve bite function in TMD, although confidence in cumulative evidence ranged from moderate to very low. There was no evidence that patient education improved bite function.
CONCLUSION
Conservative interventions may be helpful to address bite-related impairments associated with TMD, although further research is needed to improve the quality of evidence and direct clinical guidelines.
Topics: Dental Occlusion; Humans; Mastication; Range of Motion, Articular; Self Report; Temporomandibular Joint Disorders
PubMed: 35108410
DOI: 10.1111/joor.13307 -
CoDAS 2022To review the effects of low-level laser photobiomodulation on masticatory function and mandibular movements in adults with temporomandibular disorder. (Meta-Analysis)
Meta-Analysis
Effects of low-level laser photobiomodulation on the masticatory function and mandibular movements in adults with temporomandibular disorder: a systematic review with meta-analysis.
PURPOSE
To review the effects of low-level laser photobiomodulation on masticatory function and mandibular movements in adults with temporomandibular disorder.
RESEARCH STRATEGIES
Search in PubMed, Web of Science, Scopus, EMBASE, Cochrane, LILACS, ScienceDirect, and Google Scholar, using the following descriptors: "temporomandibular joint disorders", "low-level light therapy", "low-level laser therapy", "mastication", and "mandible".
SELECTION CRITERIA
Randomized clinical trials in adults with temporomandibular disorder, using low-level laser and assessing the mastication and mandibular movements.
DATA ANALYSIS
Firstly, the titles and abstracts of all retrieved studies were read. Then, only the studies selected in the first stage were read in full and assessed regarding eligibility. After the selection, the characteristics, methodological quality, and quality of evidence of the studies included in the review were analyzed. In the meta-analysis, the mean amplitude of mouth opening was considered as a measure of intervention effect.
RESULTS
The 10 articles included in the review had quite different results one from the other, especially regarding the amplitude of mouth opening, while the mastication was assessed in only one of them. Most studies had a high risk of bias, demonstrating a low methodological quality. Significantly higher results for photobiomodulation were identified in the six studies included in the meta-analysis.
CONCLUSION
Due to the scarcity in the literature, there is not enough evidence of the effects of low-level laser photobiomodulation on mastication. As for the mandibular movements, this intervention presented significant results, particularly in the amplitude of mouth opening.
Topics: Adult; Humans; Lasers; Low-Level Light Therapy; Mandible; Mastication; Temporomandibular Joint Disorders
PubMed: 35107512
DOI: 10.1590/2317-1782/20212021138 -
Annals of Global Health 2022Areca nut (AN), the principal ingredient of betel quid (BQ) has been categorized as a human carcinogen associated with various cancers of upper aerodigestive tract.... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Areca nut (AN), the principal ingredient of betel quid (BQ) has been categorized as a human carcinogen associated with various cancers of upper aerodigestive tract. However, there has been no attempt at summarizing the risk reversal of oral and other cancers after cessation of BQ with or without tobacco (BQ+T/BQ-T).
OBJECTIVE
To analyze the effect of cessation of betel quid without tobacco (BQ-T) and with tobacco (BQ+T) on reversal of the risk of oral, pharyngeal and oesophageal cancers.
METHODS
A systematic literature search was conducted for publications evaluating risk of these three cancers among current and former users of BQ-T or BQ+T. The overall as well as subgroup meta-relative risks (meta-RR) were estimated using random-effect models.
RESULTS
A total of 14 studies, seven each providing estimates for BQ-T and BQ+T, were identified. For BQ-T and oral cancer, a 28.9% risk reversal was observed among former users (meta-RR 5.61, 95% CI 2.24-14.04) compared to current users (meta-RR 7.89, 95% CI 3.90-15.98). A risk reversal of 48% was noted for pharyngeal cancer - former users (meta-RR 2.50, 95% CI 1.43-4.38), current users (meta-RR 4.81, 95% CI 2.05-11.30). For oesophageal cancer, no appreciable difference in risk was observed between current and former users.For BQ+T and oral cancer the overall meta-RR indicated a higher risk in former than in current users. However, sensitivity analysis including only better-quality studies showed a modestly lower cancer risk in former than in current users. Compared to current users, the risk in former users who quit less than 10 years ago (meta-RR 1.21, 95% CI 0.90-1.63) was increased, but decreased in former users who quit more than 10 years ago (meta-RR 0.72, 95% CI 0.48-1.07).
CONCLUSION
Our analysis highlights for the first time the potential of risk reversal for oral and pharyngeal cancers following cessation of BQ-T and for oral cancer in long-term quitters (greater than 10 years) of BQ+T. The suggestive evidence from this systematic review further supports the imperative need of a strong policy to reduce the initiation of BQ use and inclusion of interventions for BQ cessation in cancer control efforts especially in geographic regions where BQ chewing is prevalent.
Topics: Areca; Esophageal Neoplasms; Humans; Mastication; Mouth Neoplasms; Nicotiana
PubMed: 35087705
DOI: 10.5334/aogh.3643