Clinical characteristics and salivary biomarkers of burning mouth syndrome.

OBJECTIVES: To investigate the clinical characteristics and salivary biomarkers in each type of burning mouth syndrome (BMS) patients. MATERIALS AND METHODS: Ninety-eight postmenopausal female patients with BMS were included. Fifty and 21 patients were assigned to the primary and secondary groups, respectively. Twenty-seven patients with both primary and secondary characteristics were assigned to the intermediate group. Comprehensive clinical characteristics and salivary biomarkers were analyzed. RESULTS: Significant differences in age, proportion of hyposalivator patients based on unstimulated whole saliva (UWS), symptom distribution, severties of burning sensation and effect of oral complaints in daily life (Eff-life), and positive symptom distress index (PSDI) were observed among the three groups. The primary group had significant higher UWS flow rate, fewer UWS hyposalivator proportions, and lesser severity of Eff-life than the secondary group. The intermediate group had significantly greater intensities of burning sensation and Eff-life and higher PSDI score than did the primary group. The primary group had significantly higher cortisol and dehydroepiandrosterone (DHEA) levels in stimulated whole saliva than did the secondary group. CONCLUSIONS: This study's findings show that clinical characteristics differentiate each BMS type. Cortisol and DHEA levels are potential salivary biomarkers for discriminating between the primary and secondary types of BMS.

Effects of Zinc Compounds on the Enzymatic Activities of Lysozyme and Peroxidase and Their Antifungal Activities.

This study aimed to investigate the effects of zinc compounds on the enzymatic activities of lysozyme, peroxidase, and the glucose oxidase-mediated peroxidase (GO-PO) system and their antifungal activities. Four different zinc compounds (zinc chloride, gluconate, lactate, and sulfate) were incubated with hen egg-white lysozyme (HEWL), bovine lactoperoxidase (bLPO), the GO-PO system, and human unstimulated whole saliva in solution and on a hydroxyapatite surface. Enzymatic activities of lysozyme, peroxidase, and the GO-PO system were measured through the hydrolysis of Micrococcus lysodeikticus, oxidation of fluorogenic 2',7'-dichlorofluorescin, and glucose assay, respectively. Interactions between zinc and enzymes were analyzed by surface plasmon resonance (SPR). The minimum inhibitory concentration (MIC) and candidacidal activities of zinc compounds were examined against three Candida albicans strains. Zinc gluconate and sulfate significantly increased the enzymatic activities of salivary lysozyme in the solution assay and of HEWL and salivary lysozyme on the hydroxyapatite surface. However, all examined zinc compounds significantly decreased the enzymatic activities of bLPO and salivary peroxidase in solution and on the surface. SPR analyses revealed binding of zinc to lysozyme and peroxidase, with affinity differing according to the zinc compounds. The MIC of zinc compounds against C. albicans was 1.0-2.4 mM. Candidacidal activities were 17.7-38.8% and 23.7-47.0% at 1.0 and 10 mM concentrations, respectively. In conclusion, zinc compounds enhanced lysozyme activity but inhibited peroxidase activity. Zinc compounds exhibited concentration-dependent candidacidal activity against C. albicans. Zinc compounds are potential therapeutic agents for oral health, especially for geriatric patients.

Effects of Zinc Compounds on Lysozyme, Peroxidase, and α-Amylase from the Perspective of Oral Health: a Scoping Review.

Zinc has been proposed as a topical therapeutic agent for the prevention and treatment of various oral diseases. The purpose of this scoping review was to investigate the effects of zinc on the enzymatic activities of lysozyme, peroxidase, and α-amylase from the perspective of developing oral health care products and therapeutic agents for oral diseases. A comprehensive review of the scientific literature was conducted on the direct interactions of zinc with lysozyme, peroxidase, and α-amylase from various sources. Most of the reports on the effects of zinc on the enzymatic activities of lysozyme, peroxidase, and α-amylase involved enzymes derived from bacteria, fungi, animals, and plants. Studies of human salivary enzymes were scarce. Zinc was found to inhibit the enzymatic activities of lysozyme, peroxidase, and α-amylase under diverse experimental conditions. The suggested mechanism was ionic interactions between zinc and enzyme molecules. The possibility that zinc causes structural changes to enzyme molecules has also been suggested. In conclusion, for zinc to be used as an effective topical therapeutic agent for oral health, further studies on the activity of human salivary enzymes are warranted, and additional information regarding the type and concentration of effective zinc compounds is also required.

Case series: Noninfectious myositis of temporal muscle: a report of 2 cases.

BACKGROUND: Noninfectious myositis (NIM) of the masticatory muscles is uncommon local myalgia disorder persisted by a centrally-mediated neurogenic mechanism. Due to the rarity of this condition and the lack of appropriate data regarding it, diagnosing this pathology when it affects the temporal muscle (TM) is challenging. CASE PRESENTATION: Clinical signs and symptoms, diagnostic process, and treatment outcome of 2 rare cases of NIM of the TM were presented. The signs and symptoms of the patients were not pathognomonic. There were restrictions on the mouth opening and lateral excursion of the mandible. The duration of the symptoms may not be chronic. The findings of clinical evaluation may indicate the diagnosis of anterior disc displacement (DD) without reduction of the temporomandibular joint (TMJ) and/or local myalgia. Swelling of the involved muscle could be evident and identified on palpation depending on the involved site of myositis. The axial T2-weighted magnetic resonance (MR) imaging was important for the accurate diagnosis of this rare condition. Application of non-surgical conservative treatment modalities such as administration of non-steroidal anti-inflammatory analgesics for a sufficient period of time, control of oral parafunctional habits, and jaw exercises were effective for the management of NIM of the TM. CONCLUSION: A thorough clinical examination and MR imaging including the axial T2-weighted view are required for accurate diagnosis and effective management of NIM of the TM.

Changes in the lesion surface suggesting transformation of oral potentially malignant disorders to malignancy - a report of eight cases.

BACKGROUND: In the case of oral potentially malignant disorders (OPMD), the possibility of malignant transformation of the lesion necessitates a decision on the need for an additional biopsy at each visit. Among many clinical characteristics, change on the lesion surface is one of the important factors that determine the need for additional biopsy at each visit. The purpose of the study was to provide information on the characteristics of lesions related to malignant transformation during the follow-up period of OPMD. METHODS: Eight patients (four men and four women) with OPMD that transformed into malignancy during long-term follow-up were included and their mean age was 65.8 ± 12.4 years. Clinical information and histopathological diagnosis were investigated at the initial visit and during the long-term follow-up period. The focus was on information on changes on the lesion surface at the time the lesion was confirmed to be malignant. The period from initial diagnosis to dysplasia and from dysplasia to malignancy was also investigated. RESULTS: The OPMD diagnoses were oral lichen planus or oral lichenoid lesions (n = 2), oral leukoplakia (n = 5), and hyperplastic candidiasis (n = 1). During the follow-up period of the lesions, when dysplasia was obtained by additional biopsy, changes in the lesions consisted of an increase in the size of the white or red area. The lesion surface of the OPMD showed verrucous, papillary, exophytic, corrugated, and ulcerative changes at the time of malignancy diagnosis. The period for the initial lesion to become dysplasia, from dysplasia to malignancy, and from the initial lesion to malignancy was very variable. CONCLUSIONS: Attention should be paid to verrucous, papillary, exophytic, corrugated, and ulcerative changes on the lesion surface of OPMD. Considering that the period for OPMD to become malignant is highly variable, a longer follow-up of the lesion is necessary.

The teaching of geriatric dentistry in South Korean dental schools.

OBJECTIVE: The purpose of this study was to investigate the curriculum of geriatric dentistry for undergraduates in Korean dental schools. BACKGROUND: For development purposes, it was necessary to compare geriatric dentistry education programmes in South Korea to programmes in the United States and Europe. METHODS: The most recent curriculum and related information on geriatric dentistry at the undergraduate level in all 11 dental schools in South Korea were collected by both official letter and e-mail. A symposium for gathering expert opinions to improve geriatric dentistry education in South Korea was also held. The collected data were analysed, and the expert opinions at the symposium were summarised. RESULTS: Six of 11 schools had a didactic course as compulsory and three schools as elective. The course was usually conducted as a form of integrated lectures, and the level of standardisation of lecture content was very low. There were no topics for older people who cannot access dental clinics due to functional frailty or disability. No dental school-affiliated hospitals had an independent department for geriatric dentistry. No schools provided clinical teaching for geriatric dentistry. There were no outreach programmes for geriatric dentistry. CONCLUSIONS: The educational curriculum for geriatric dentistry in South Korea was insufficient to cope with social and demographic changes. Curriculum content should include clinical practice education and needs to be focused on frail and dependent older adult patients. An essential educational curriculum and core competency for geriatric dentistry should be prepared.

Relationship between subjective taste sensations and taste strip test in patients with taste disorders with and without burning mouth syndrome.

Background/purpose: Both subjective and objective evaluations are required to assess taste function. Evaluation of taste function has important clinical significances in patients with burning mouth syndrome (BMS) due to pain-taste interactions. The purpose of this study was to investigate the relationship between subjective and objective taste evaluations in patients with taste disorders based on the presence of BMS. Materials and methods: Fifty-one patients with taste disturbances were included. The patients completed questionnaires on subjective taste sensations. The taste strip test was performed to examine objective taste function. The patients were divided into two groups: subjects with BMS (n = 24, 3 males and 21 females) and without BMS (n = 27, 8 males and 19 females). Results: Significant differences were not observed in age, age distribution, and gender distribution between the groups. There were no significant differences in self-reported taste abilities based on the presence of BMS. However, the taste strip test showed higher correct answer rates for bitterness (P = 0.027) in the patients with BMS. In addition, a significant difference (P = 0.034) was observed in the distribution of objective types of taste disorders between the groups. A significant correlation between the subjective and objective evaluation results was observed only in patients with BMS. Conclusion: In patients with taste disorders, patients with BMS had significant correlations between subjective and objective evaluations and different distributions in the types of taste disorders compared with those without BMS. The presence or absence of BMS should be evaluated in the diagnosis and management of taste disorders.

Is a neuropathic mechanism involved in the perception of oral dryness?

OBJECTIVES: The aim of the present study was to review the existing phenomena which could affect subjective oral dryness and to consider the possibility that neural processing is involved in the perception of oral dryness. DESIGN: A comprehensive review of scientific literatures relevant to contributing factors of dry mouth symptoms including salivary parameters related with oral dryness and role of neural mechanisms in perception of dry mouth symptoms was conducted. RESULTS: Several previous reports suggested the possibility of neural processing mechanisms in perception of oral dryness. The decreased pain threshold in the oral cavity of rats with dry tongue and complaints of subjective oral dryness in patients with burning mouth syndrome, of which lacked an actual decrease in salivary output and mucosal wetness, could support this idea. Sensory changes in the oral mucosa and oral dryness may have a bi-directional influence that patients with oral dryness would be more subject to neuropathic pain in the oral mucosa, and those with neuropathic pain in the oral cavity could have complaints associated with higher levels of dry mouth symptoms. CONCLUSION: A bi-directional influence between sensory change in the oral mucosa and subjective oral dryness could be assumed. We suggest the administration of neuropathic pain medications for controlling subjective oral dryness in patients without objective sign of hyposalivation.

Prediction of treatment outcome in burning mouth syndrome patients using machine learning based on clinical data.

The purpose of this study is to apply a machine learning approach to predict whether patients with burning mouth syndrome (BMS) respond to the initial approach and clonazepam therapy based on clinical data. Among the patients with the primary type of BMS who visited the clinic from 2006 to 2015, those treated with the initial approach of detailed explanation regarding home care instruction and use of oral topical lubricants, or who were prescribed clonazepam for a minimum of 1 month were included in this study. The clinical data and treatment outcomes were collected from medical records. Extreme Gradient-Boosted Decision Trees was used for machine learning algorithms to construct prediction models. Accuracy of the prediction models was evaluated and feature importance calculated. The accuracy of the prediction models for the initial approach and clonazepam therapy was 67.6% and 67.4%, respectively. Aggravating factors and psychological distress were important features in the prediction model for the initial approach, and intensity of symptoms before administration was the important feature in the prediction model for clonazepam therapy. In conclusion, the analysis of treatment outcomes in patients with BMS using a machine learning approach showed meaningful results of clinical applicability.

Clinical characteristics of temporomandibular disorders presenting posterior open bite - A report of 12 cases.

BACKGROUND/PURPOSE: There is a paucity of comprehensive information about posterior open bite (POB) in patients with temporomandibular disorders (TMD) because of its rare prevalence. The purpose of this study was to investigate the etiologies, clinical characteristics, and treatment outcomes of patients with TMD presenting POB. MATERIALS AND METHODS: This study includes a careful review of medical records and imaging findings of 12 patients with TMD (seven men and five women, 50.9 ±â€¯19.2 years, 15-72 years) complaining of POB. RESULTS: In total, 11 had unilateral POB, whereas 1 had bilateral POB. In 11 patients, POB was caused by inflammatory disorders of temporomandibular joint (TMJ). In the remaining one patient, TMJ medial disc displacement (MDD) was responsible for POB. Of 11 patients with inflammatory conditions of TMJ, four patients had unilateral TMJ internal derangement (ID), two had bilateral TMJ ID, and one had rheumatism. POB was resolved in 10 of 11 patients with TMJ inflammation following the administration of non-steroidal anti-inflammatory drugs and self-management instructions. Prosthodontic treatment was needed in one patient to resolve POB. POB was resolved in the patient with TMJ MDD after stabilization splint therapy. CONCLUSION: POB in patients with TMD was mostly caused by inflammatory disorders of TMJ. TMJ MDD could also be a reason. Although almost all POB was resolved by conservative treatments including medications, the possibility of prosthodontic, orthodontic, or surgical treatments also must be considered.

Oral health-related quality of life and associated factors in patients with xerostomia.

OBJECTIVE: This study aimed to investigate clinical and demographic factors associated with oral health-related quality of life (OHRQoL) in patients with xerostomia. METHODS: Forty-one patients (55.2 ± 13.8 years) with xerostomia as a chief complaint participated in the study. Comprehensive information about clinical and demographic characteristics of the patients with xerostomia, xerostomia-related symptoms and behaviours, and xerostomia-associated complaints was investigated using a xerostomia questionnaire. Flow rates of unstimulated and stimulated whole saliva were measured. The Oral Health Impact Profile-14 (OHIP-14) score was used to assess the OHRQoL of patients. The relationships between various factors and the OHIP-14 score were assessed by simple and multiple linear regression analyses. RESULTS: The OHIP-14 score of patients with xerostomia was high (44.3 ± 13.2). Characteristics of the patients with xerostomia associated with high OHIP-14 score were the intensity of xerostomia-related symptoms, frequency of xerostomia-related behaviours and the presence of speaking difficulty. Results from multiple linear regressions found that self-reported amount of saliva in usual, everyday life (ß = 0.622, p = 0.012) and the presence of a speaking difficulty (ß = 0.348, p = 0.014) had significant adversely affected the OHRQoL in patients with xerostomia. CONCLUSIONS: Subjective perceptions of the amount of saliva in the mouth and the experience of speaking difficulty affected the OHRQoL in patients with xerostomia.

Oral health-related quality of life and associated factors in patients with burning mouth syndrome.

OBJECTIVE: The purpose of this study was to assess oral health-related quality of life (OHRQoL) in patients with burning mouth syndrome (BMS) and to identify clinical factors associated with OHRQoL. METHODS: Fifty-seven patients with BMS (56.4 ± 10.7 years) participated in the study. Patients underwent oral examination, laboratory tests, psychological evaluation, measurement of salivary flow rates and evaluation of clinical characteristics using a BMS questionnaire. The OHRQoL of patients was assessed using the Oral Health Impact Profile-14 (OHIP-14). RESULTS: The OHIP-14 score for patients with BMS was 38.6 ± 12.8. Patients had higher scores for the psychological discomfort and physical pain dimensions of the OHIP-14. The intensity of taste disturbance or xerostomia symptoms (ß = 0.464, P < .001), worry about symptoms (ß = 0.307, P = .020), and results of psychological evaluation (ß = 0.311, P = .026) were significantly associated with OHIP-14 score. Multiple linear regression showed that the intensity of taste disturbance or xerostomia symptoms was significantly associated with decreased OHRQoL (ß = 0.637, P = .026). CONCLUSIONS: This study suggests that severity of taste disturbance or xerostomia is an important factor that influences OHRQoL in patients with BMS.

Treatment outcomes and related clinical characteristics in patients with burning mouth syndrome.

OBJECTIVES: To evaluate the treatment outcomes of medication therapies in patients with burning mouth syndrome (BMS) and to identify the clinical characteristics that may affect the efficacy of prescribed medications. METHODS: This is a retrospective study of 769 patients with oral burning sensations. Of these patients, 420 patients diagnosed as the primary BMS received an "Initial Approach" that involved a detailed explanation about its etiopathophysiology, self-care instruction, and use of an oral lubricant. Neuropathic medications were prescribed for 277 patients who did not respond to the initial approach. Clinical characteristics, prescribed medications, and changes in intensity of oral symptoms were reviewed. RESULTS: Clonazepam was administered as the first-line medication. Alpha-lipoic acid (ALA), gabapentin, and nortriptyline were commonly administered in combination with clonazepam. More than two-thirds of the patients reported a marked improvement in oral symptoms after treatments with combination of neuropathic medications and ALA. The efficacies of the initial approach and clonazepam had significant positive associations with the initial intensity of oral symptoms and significant negative associations with depression. CONCLUSIONS: Clonazepam therapy in combination with appropriate medications was effective for managing patients with BMS. The initial intensity of oral symptoms and psychological status were significantly associated with treatment outcomes.

Developing a clinical presentation dental education model and a pilot test.

INTRODUCTION: Accurate clinical decision-making of dentists should be based on their knowledge and experience. In the past 10 years, interest in competency-based dentistry education has rapidly increased, but there has been little attention paid to methods of improving dental education competency. The purpose of this study was to develop a clinical presentation education model that provides opportunities for students to practice problem-solving from the moment they greet the patient so that students can obtain the practical experience of competency-based education and the effectiveness of this model can be confirmed through pilot test. METHODS: This article is divided two parts: First, developing the clinical presentation dental education model (CPDEM) and Second, a pilot study adopted CPDEM. To confirm the effectiveness of this model, the students' satisfaction, their perception of self-achievement were analysed. RESULTS: Clinical presentation dental education model has been developed to provide practice-related education experience and provide linkage between basic science and clinical science. The result of applying this education model to 10 students as a pilot test was shown an overall high satisfaction level. In addition, self-achievement students' reported of all intended competencies was higher than for non-participating students of this model. CONCLUSIONS: This study focuses on practical education centring on clinical presentation. This model could get a meaningful and realistic experiences through the practice using clinical presentation of patients, use their metacognition for organizing and memorizing the patient's case by using concept map. It can be used as a future instructional method to enhance students' competency.

Viscosities of mixtures of hyaluronic acids with different molecular weights and their effects on enzymatic activities of lysozyme and peroxidase.

OBJECTIVES: To investigate the viscosity values of mixtures of hyaluronic acids with different molecular weights and the effects of these mixtures on the enzymatic activities of lysozyme and peroxidase. MATERIALS AND METHODS: Mixtures of high molecular weight (1 or 2 MDa) and low molecular weight (10 or 100 kDa) hyaluronic acids at different concentrations were used for viscosity measurements. Hyaluronic acid mixtures showing viscosity values similar to those of human whole saliva were used for enzyme experiments in solution and on hydroxyapatite surface. Hen egg-white lysozyme, bovine lactoperoxidase, and human whole saliva were used as enzyme sources. Lysozyme activity was measured by hydrolysis of fluorescein-labeled Micrococcus lysodeikticus. Peroxidase activity was measured by oxidation of fluorogenic 2',7'-dichlorofluorescein to fluorescing 2',7'-dichlorofluorescein. RESULTS: The mixtures of 1 MDa (0.5 mg/mL) or 2 MDa (0.2 mg/mL) hyaluronic acid with 10 kDa (2.0 mg/mL) or 100 kDa (0.1 mg/mL) hyaluronic acid had viscosity values similar to those of human whole saliva at shear rates, reflecting normal oral functions. Compared with single molecular weight hyaluronic acids, these mixtures showed viscosity values more similar to those of human whole saliva. The mixtures inhibited lysozyme and peroxidase activities on the hydroxyapatite surfaces; however, the degree of inhibition did not differ from that of hyaluronic acid of 1 or 2 MDa only. CONCLUSIONS: Compared with single molecular weight hyaluronic acids, hyaluronic acid mixtures showed viscosity values more similar to those of human whole saliva, without additional inhibitory effects on lysozyme and peroxidase activities. CLINICAL RELEVANCE: Hyaluronic acid mixtures offer distinct advantages for the development of saliva substitutes.

Relationships between gustatory function tests.

OBJECTIVES: To investigate the relationships among four different gustatory function tests in healthy young adults: electrogustometry (EGM), filter paper disk (FPD), whole-mouth, and taste strip methods. The relationships of the results of gustatory function tests with salivary flow rate were also investigated. METHODS: Sixty healthy young adults (30 men, 26.9 ± 4.7 years; 30 women, 25.7 ± 4.6 years) who did not have disorders or conditions related with gustatory function were included. Four different gustatory function tests using the EGM, FPD, whole-mouth, and taste strip methods were performed in each participant with 2- to 3-day intervals between tests. The flow rates of unstimulated and stimulated whole saliva were measured. RESULTS: There were no significant differences between sexes in all the examined gustatory function tests. The levels of correlations between the gustatory function tests were low. The EGM threshold correlated with the taste score of the FPD method in the chorda tympani nerve area. Different chemical gustatory function tests did not correlate significantly in any of the four taste qualities. Salivary flow rates did not correlate with taste perception. CONCLUSIONS: The correlations between gustatory function tests were weak. A significant correlation was found between the results of EGM and FPD methods in the chorda tympani nerve area.

Development of an Oral and Maxillofacial Frailty Index: A preliminary study.

OBJECTIVE: The purpose of this study is to develop an index to measure oral and maxillofacial frailty in older adults as an acceptable screening tool. METHODS: Three hundred adults (aged ≥ 50 years) participated in this study by telephone interview. Ten candidate items for the Oral and Maxillofacial Frailty Index (OMFI) and 20 matched detailed items for oral and maxillofacial functions were asked. Information about sociodemographic and oral health-related variables was also obtained. The test-retest reliability of the 10 candidate items was determined. Correlations of the 10 candidate items with the 20 detailed items or sociodemographic and oral health-related variables were analysed to test the validity of the candidate items. To suggest optimal items for the OMFI, five different models with different numbers of items were constructed and evaluated based on their associations with main variables. RESULTS: The overall internal consistency of the 10 candidate items was .704, and the Cronbach's alpha value of each item was .23-.55. The test-retest reliability was excellent. There were significant correlations between the 10 candidate and 20 matched detailed items. The score of the 10 candidate items was significantly different according to gender, education level and oral health-related variables. The final five items for the OMFI were difficulties in chewing, the necessity of water when eating dry food, difficulties in jaw or tongue movements, difficulties in speaking or pronunciation and difficulties in facial expression. CONCLUSIONS: The five items could be used as a screening tool for evaluating oral and maxillofacial frailty in older adults.

Salivary biomarkers of inflammation and oxidative stress in healthy adults.

OBJECTIVES: Diagnostic value of saliva depends on the reproducibility of data in repeatedly collected samples and predictable correlations between saliva and blood. We aimed to investigate the reliability, blood reflectance, and influence of blood contamination in the analysis of inflammatory and oxidative stress biomarkers in saliva samples. DESIGN: In total, 37 healthy young male participants (26.7 ± 2.2 years) were included. Unstimulated whole saliva and blood samples were collected on the first visit, and saliva samples were collected again after 2-3 days. The concentrations of total protein and inflammatory [C-reactive protein (CRP), IL-1ß, IL-6, and TNF-α] and oxidative stress [8-hydroxy-2'-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and total antioxidant capacity (TAC)] biomarkers in saliva and blood, and as well as blood contamination biomarkers (transferrin and hemoglobin) in saliva were analyzed. RESULTS: The intra-class correlations of all examined biomarkers except TNF-α were fair to excellent. Significant positive correlations between CRP and IL-6 and between total protein and TAC were stable in the saliva samples collected on different days. Notably, IL-6 was the only biomarker that showed a significant correlation between saliva and blood. As the concentration of salivary transferrin increased, the saliva/blood ratios of total protein and TAC also increased. The concentration of salivary hemoglobin did not affect the saliva/blood ratios of biomarkers. CONCLUSIONS: The findings of this study are limited to healthy young males. For clinical applications, studies on salivary diagnostics should be performed for individual disease and health conditions, demographic characteristics, and biomarkers.

Blood contamination in salivary diagnostics: current methods and their limitations.

The use of saliva samples in clinical studies has increased. However, the diagnostic value of whole saliva is compromised in the presence of blood contamination, owing to the higher levels of analytes in blood compared with those in saliva. The aim of this study was to review the existing methods and their limitations for measuring the levels of blood contamination in saliva. A literature search was performed using Web of Science, SCOPUS, and PubMed databases and 49 articles dealing with salivary diagnostics and measurements of blood contamination were included. Five methods for measuring the degree of blood components in saliva were discussed, including "visual inspection", use of "strip for urinalysis", and detection of plasma proteins such as "hemoglobin", "albumin", and "transferrin". Each method has its limitations, and transferrin has been regarded as the most reliable and valid marker for blood contamination in saliva. However, transferrin in whole saliva may not be solely a product of blood, and its level in whole saliva can be influenced by several factors such as age, gonadal hormones, salivary flow rate, chewing performance, and oral microorganisms. In conclusion, when quantitatively analyzing whole saliva samples, the influence of blood contamination should be considered.