Outcomes of primary root canal therapy: An updated systematic review of longitudinal clinical studies published between 2003 and 2020.

BACKGROUND: A comprehensive effort to evaluate outcomes of primary root canal therapy (RCT) between 1966 and 2002 was published by Ng et al. (2007, International Endodontic Journal, 40, 921; 2008, International Endodontic Journal, 41, 6). Changes in endodontic materials and treatment methods warrant an updated analysis of outcomes. OBJECTIVES: This study aimed to (1) quantify the success rates of primary RCT published between 2003 and 2020; and (2) investigate the influence of some characteristics known/suspected to be associated with treatment outcomes. METHODS: An electronic search was performed in the following databases (01-01-2003 to 12-31-2020): Pubmed, Embase, CINHAL, Cochrane and Web of Science. Included study designs were longitudinal clinical studies (randomized control trials, cohort studies, retrospective observational studies). Studies with at least twelve-months of post-operative review and success rates based on clinical and radiographic criteria were analysed. The terms 'strict' (complete resolution of periapical lesion) or 'loose' (reduction in size of existing periapical lesion) were used to describe the outcome criteria. Weighted, pooled success rates were calculated. Random effects meta-regression models were used to investigate potential sources of statistical heterogeneity. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach was used to evaluate for quality assessment of the included studies. RESULTS: Forty-two studies were included in the review. Meta-analyses showed that the weighted pooled success rates were estimated to be 92.6% (95% CI: 90.5%-94.8%) under 'loose criteria' and 82.0% (95% CI: 79.3%-84.8%) under 'strict' criteria. The most significant areas of study heterogeneity were year of publication and qualification of operator. The majority (64.29%) of studies were considered to be of low quality of evidence. DISCUSSION: Biological factors continue to have the most significant impact on RCT outcomes. The technological method of instrumentation had no significant effect. The quality of evidence was based primarily on study design and only randomized control trials were considered to be 'high' quality of evidence. CONCLUSIONS: The reported success rates show improvement over time. Weighted success rates for studies with a minimum of four-years follow-up had better outcomes, compared to those with less than four years, when 'strict criteria' were used. REGISTRATION: PROSPERO database (CRD42021226311).

What is the societal economic cost of poor oral health among older adults in the United States? A scoping review.

OBJECTIVE: To assess the state of the literature in the United States quantifying the societal economic cost of poor oral health among older adults. BACKGROUND: Proponents of a Medicare dental benefit have argued that addressing the growing need for dental care among the US older adult population will decrease costs from systemic disease and other economic costs due to oral disease. However, it is unclear what the current economic burden of poor oral health among older adults is in the United States. METHODS: We conducted a scoping review examining the cost of poor oral health among older adults and identified cost components that were included in relevant studies. RESULTS: Other than oral cancer, no studies were found examining the economic costs of poor oral health among older adults (untreated tooth decay, gum disease, tooth loss and chronic disease/s). Only two studies examining the costs of oral cancer were found, but these studies did not assess the full economic cost of oral cancer from patient, insurer and societal perspectives. CONCLUSIONS: Future work is needed to assess the full economic burden of poor oral health among older adults in the United States, and should leverage novel linkages between medical claims data, dental claims data and oral health outcomes data.

World Workshop on Oral Medicine VI: a systematic review of medication-induced salivary gland dysfunction: prevalence, diagnosis, and treatment.

OBJECTIVES: Medication-induced salivary gland dysfunction (MISGD) causes significant morbidity resulting in decreased quality of life. This systematic review assessed the literature on the prevalence, diagnosis, treatment, and prevention of MISGD. MATERIALS AND METHODS: Electronic databases were searched for articles related to MISGD through June 2013. Four independent reviewers extracted information regarding study design, study population, interventions, outcomes, and conclusions for each article. Only papers with acceptable degree of relevance, quality of methodology, and strength of evidence were retained for further analysis. RESULTS: There were limited data on the epidemiology of MISGD. Furthermore, various methods were used to assess salivary flow rate or xerostomia. Preventive and therapeutic strategies included substitution of medications, oral, or systemic therapy with sialogogues, use of saliva substitutes or of electro-stimulating devices. Although there are promising approaches to improve salivary gland function, most studies are characterized by small numbers and heterogeneous methods. CONCLUSIONS: Physicians and dentists should identify the medications associated with xerostomia and salivary gland dysfunction through a thorough medical history. Preferably, health care providers should measure the unstimulated and stimulated whole salivary flow rates of all their patients so that these values can be used as a baseline to rate the complaints of patients who subsequently claim to experience xerostomia or salivary gland dysfunction as well as the possibilities of effectively treating this condition. CLINICAL RELEVANCE: MISGD remains a major burden for the population. This systematic review provides a contemporary in-depth description of the diagnosis and treatment of MISGD.

A study of high front vowels with articulatory data and acoustic simulations.

The purpose of this study is to test a methodology for describing the articulation of vowels. High front vowels are a test case because some theories suggest that high front vowels have little cross-linguistic variation. Acoustic studies appear to show counterexamples to these predictions, but purely acoustic studies are difficult to interpret because of the many-to-one relation between articulation and acoustics. In this study, vocal tract dimensions, including constriction degree and position, are measured from cinéradiographic and x-ray data on high front vowels from three different languages (North American English, French, and Mandarin Chinese). Statistical comparisons find several significant articulatory differences between North American English /i/ and Mandarin Chinese and French /i/. In particular, differences in constriction degree were found, but not constriction position. Articulatory synthesis is used to model the acoustic consequences of some of the significant articulatory differences, finding that the articulatory differences may have the acoustic consequences of making the latter languages' /i/ perceptually sharper by shifting the frequencies of F(2) and F(3) upwards. In addition, the vowel /y/ has specific articulations that differ from those for /i/, including a wider tongue constriction, and substantially different acoustic sensitivity functions for F(2) and F(3).

Analyses of vocal tract cross-distance to area mapping: an investigation of a set of vowel images.

Traditional models of mappings from midsagittal cross-distances to cross-sectional areas use only local cross-distance information. These are not the optimal models on which to base the construction of a mapping between the two domains. This can be understood because phonemic identity can affect the relation between local cross-distance and cross-sectional area. However, phonemic identity is not an appropriate independent variable for the control of an articulatory synthesizer. Two alternative approaches for constructing cross-distance to area mappings that can be used for articulatory synthesis are presented. One is a vowel height-sensitive model and the other is a non-parametric model called loess. These depend on global cross-distance information and generally perform better than the traditional models.

Sagittal area of the vocal tract in young female children.

OBJECTIVE: To measure the sagittal areas of the front and back cavities of the vocal tract in children acquiring speech. PATIENTS AND METHODS: Ten female children were selected from the Serial Experimental collection of the Burlington Growth Centre in Toronto, Canada. Each of the 10 children was seen annually from ages 3 through 8. Data collections included lateral cephalograms in occlusion. We traced those cephalograms and identified landmarks to delineate the front and back cavities. The sagittal areas of the front and back cavities were calculated. A measure of the angle of the head to the cervical vertebrae was made. RESULTS: Front cavities were larger and grew faster. For both front and back cavities, age, angle measure, and the interaction of age and angle measure were significant. CONCLUSION: Space available for the tongue to maneuver is greater anteriorly than posteriorly even when the jaw is maximally elevated.

Implications of peripheral muscular and anatomical development for the acquisition of lingual control for speech production: a review.

OBJECTIVES: Normally developing children learn to produce intelligible speech during rapid, non-uniform growth of their articulators and other vocal tract structures. The purpose of this review is to focus attention on the consequences of peripheral growth and development for the acquisition of lingual control for speech production. This paper (1) reviews physiological underpinnings of tongue shaping and movements that are likely to be changing in young children; (2) estimates, from previously published studies, the net consequences of growth of multiple vocal tract structures on lingual control; (3) integrates our findings with the example of [R] production, and (4) highlights areas where further investigations would be most helpful. PATIENTS AND METHODS: The authors searched the literature, including the PubMed database, for studies of the development of muscle proteins, muscle fibers, and motor units of the tongue, and of the growth of the tongue, jaw, adenoids, soft and hard palates, oral and pharyngeal cavities, and the vocal tract as a whole. CONCLUSIONS: Substantial anatomical and muscular data sets focused on children from 1-4 years of age, and rigorous definitions of the tongue boundaries are needed.

A systematic review on incidental findings in cone beam computed tomography (CBCT) scans.

OBJECTIVES: Cone beam CT's use (CBCT) in dentistry is increasing. Incidental findings (IFs: discoveries unrelated to the original purpose of the scan), are frequently found as a result of a large field of view. The aim of the systematic review is to analyze present literature on IFs using CBCT. METHODS AND MATERIALS: The authors searched online databases of studies and assessed the prevalence of IFs among patients undergoing head and neck CBCT scans. STROBE criteria was used to evaluate the quality of the studies. RESULTS: The original search retrieved 509 abstracts of which only 10 articles met the inclusion criteria. The sample size varied between 90 and 1000 participants. The frequency of IFs of the selected articles were 24.6-94.3%. The most common non-threatening IFs were found in the airway, such as mucous retention cyst (55.1%) and sinusitis (41.7%). Other non-threatening IFs were soft tissue calcifications such as calcified stylohyloid ligament (26.7%), calcified pineal gland (19.2%), and tonsillolith (14.3%). Threatening IFs were rare findings (1.4%). Three articles reported incidental carotid artery calcifications with a prevalence of 5.7-11.6%. Pathological findings were not common between the articles, but still relevant (2.6%). The studies had a risk of bias varying from moderate to low. CONCLUSIONS: There is a high frequency of IFs, yet not all of them require immediate medical attention. The low prevalence of threatening IFs emphasizes that CBCT should not be considered a substitution for conventional radiographs, but when used, the scans should be evaluated by a maxillofacial radiologist.

A Guide to Medications Inducing Salivary Gland Dysfunction, Xerostomia, and Subjective Sialorrhea: A Systematic Review Sponsored by the World Workshop on Oral Medicine VI.

BACKGROUND: Medication-induced salivary gland dysfunction (MISGD), xerostomia (sensation of oral dryness), and subjective sialorrhea cause significant morbidity and impair quality of life. However, no evidence-based lists of the medications that cause these disorders exist. OBJECTIVE: Our objective was to compile a list of medications affecting salivary gland function and inducing xerostomia or subjective sialorrhea. DATA SOURCES: Electronic databases were searched for relevant articles published until June 2013. Of 3867 screened records, 269 had an acceptable degree of relevance, quality of methodology, and strength of evidence. We found 56 chemical substances with a higher level of evidence and 50 with a moderate level of evidence of causing the above-mentioned disorders. At the first level of the Anatomical Therapeutic Chemical (ATC) classification system, 9 of 14 anatomical groups were represented, mainly the alimentary, cardiovascular, genitourinary, nervous, and respiratory systems. Management strategies include substitution or discontinuation of medications whenever possible, oral or systemic therapy with sialogogues, administration of saliva substitutes, and use of electro-stimulating devices. LIMITATIONS: While xerostomia was a commonly reported outcome, objectively measured salivary flow rate was rarely reported. Moreover, xerostomia was mostly assessed as an adverse effect rather than the primary outcome of medication use. This study may not include some medications that could cause xerostomia when administered in conjunction with others or for which xerostomia as an adverse reaction has not been reported in the literature or was not detected in our search. CONCLUSIONS: We compiled a comprehensive list of medications with documented effects on salivary gland function or symptoms that may assist practitioners in assessing patients who complain of dry mouth while taking medications. The list may also prove useful in helping practitioners anticipate adverse effects and consider alternative medications.

Prevention of root caries: a literature review of primary and secondary preventive agents.

PURPOSE: This literature review summarizes the effectiveness of the seven leading root caries preventive agents and provides recommendations for use of those agents in clinical practice with older adults and vulnerable elderly. METHOD: Studies were eligible if they assessed the effectiveness of either fluoride, chlorhexidine, xylitol, amorphous calcium phosphate, sealants, saliva stimulators, or silver diamine fluoride to prevent/control root caries in an English language articles between 1979 and 2010. RESULTS: In the 31 eligible studies, the most effective primary (1°) prevention agents had reductions in RC incidence ranging from 72% to nearly 200% as compared to a placebo while for secondary (2°) prevention, the best agents demonstrated arrest rates between 67 and 80%. CONCLUSION: For 1° prevention of root caries the recommended "best choice" is a 38% Silver Diamine Fluoride solution professionally applied annually, while for the 2° prevention of root caries, the recommended "best choice" is a 22,500 ppm Sodium Fluoride varnish professionally applied every 3 months.

Perception of synthetic vowel exemplars of 4-year-old children and estimation of their corresponding vocal tract shapes.

Formant scalings for vowel exemplars of American 4 year olds who were imitating adult production were used along with published data of American adult male vowel production to synthesize /a, ae, u, i/. Other vowel exemplars were also synthesized. Adult listeners were asked to categorize these synthetic vowels in a forced choice task. With some exceptions, the formant frequencies preferred for the vowels /a, ae, u, i/ were close to the published data. In order to gain insight on children's articulation during imitation of vowels /a, ae, u, i/, a five-tube model was used in an algorithm to infer vocal tract shape from the first three formant frequencies of the adult productions, the formant frequencies derived for 4 year olds by scaling, and formant frequencies for 4 year olds derived based on the listening experiments. It was found that the rear tube length for the children, in proportionate terms, was nearly always greater than that of the adult. The rear tube length was proportionately twice as long in children compared to adults for the vowel /u/. Tongue root flexibility and the oblique angle between the pharynx and mouth may be more important than pharynx length in determining formant scalings for 4 year old children.

Secant lines in a preliminary study of phonetic reduction of /I/ and /epsilon/.

Two subjects from the X-Ray Microbeam Speech Production Database were examined in their production of the vowels /I/ and /epsilon/ in alveolar and dental consonant contexts. Secant lines, or first-order splines, between the three most anterior pellets were examined at vowel critical times. These critical times were zero crossings in the tangential acceleration of the midpoints of the secant lines. We expected and found, in general, that vowel reduction occurred as a function of vowel duration in measures of the secant line midpoint-to-palate distance and secant line orientation at vowel critical times. The shorter the vowel, the smaller the distance of the secant line midpoints to the palate and the less downward the orientation of the secant lines at the vowel critical times. Phonetic reduction was also apparent in the formant frequencies. There were differences between the speakers in terms of the range of vowel duration and degree of reduction. The subjects differed in the functional parts of the tongue spanned by the secant lines and the shape of their palates. These differences were factors in the observed relations between formant frequencies and the articulatory, secant line measures for each subject.

Development of [j] in young, midwestern, American children.

Beginning at the age of about 14 months, eight children who lived in a rhotic dialect region of the United States were recorded approximately every 2 months interacting with their parents. All were recorded until at least the age of 26 months, and some until the age of 31 months. Acoustic analyses of speech samples indicated that these young children acquired [inverted r] production ability at different ages for [inverted r]'s in different syllable positions. The children, as a group, had started to produce postvocalic and syllabic [inverted r] in an adult-like manner by the end of the recording sessions, but were not yet showing evidence of having acquired prevocalic [inverted r]. Articulatory limitations of young children are posited as a cause for the difference in development of [inverted r] according to syllable position. Specifically, it is speculated that adult-like prevocalic [inverted r] production requires two lingual constrictions: one in the mouth, and the other in the pharynx, while postvocalic and syllabic [inverted r] requires only one oral constriction. Two lingual constrictions could be difficult for young children to produce.