Common Oral Conditions: A Review.

Importance: Dry mouth, oral candidiasis, and recurrent aphthous ulcers are 3 of the most common oral conditions that may be associated with patient discomfort, decreased quality of life, and morbidity. Observations: In a meta-analysis of 26 population-based cohort and cross-sectional studies, the global prevalence of dry mouth symptoms was 23% (95% CI, 18% to 28%), placing individuals at risk of oral candidiasis, dental caries, dysgeusia, masticatory/speech impairment, and oropharyngeal dysphagia. Dry mouth is associated with using more than 3 oral medications per day (odds ratio [OR], 2.9 [95% CI, 1.4 to 6.2]), head and neck radiation, and Sjögren disease. Symptoms may include difficulty swallowing and speaking, thirst, and halitosis. Dry mouth is associated with an 11.5% (95% CI, 3.6% to 27%) higher risk of oral candidiasis, based on a meta-analysis of 6 observational cohorts. Management of dry mouth includes mechanical salivary stimulants, oral moisturizers, and/or systemic sialagogues. Oral candidiasis is an opportunistic fungal infection caused by overgrowth of the Candida genus with C albicans, which accounts for 76.8% of infections. The prevalence of oral candidiasis is higher in patients who are immunosuppressed, for example, those with HIV (35% [95% CI, 28% to 42%]) and those with salivary gland hypofunction (OR, 3.02 [95% CI, 1.73 to 5.28]). Common risk factors associated with oral candidiasis include use of antibiotics (P = .04) and oral mucosal disorders such as lichen planus. Oral burning and dysgeusia are common symptoms of oral candidiasis. Treatment includes addressing risk factors and use of topical and/or systemic antifungal medications. Recurrent aphthous stomatitis is characterized by symptomatic round or oval oral ulcers, which are covered by a gray-white fibrin layer and encircled by an erythematous ring. A meta-analysis of 10 case-controlled studies revealed an increased risk of recurrent aphthous stomatitis associated with polymorphism of IL-1ß (+3954C/T) (OR, 1.52 [95% CI, 1.07 to 2.17]) and IL-1ß (-511C/T) (OR, 1.35 [95% CI, 1.09 to 1.67]). Another meta-analysis of 9 case-control studies reported that patients with recurrent aphthous stomatitis had a higher frequency of nutritional deficiencies, including vitamin B12 (OR, 3.75 [95% CI, 2.38 to 5.94]), folic acid (OR, 7.55 [95% CI, 3.91 to 14.60]), and ferritin (OR, 2.62 [95% CI, 1.69 to 4.06]). Recurrent aphthous stomatitis can be associated with systemic diseases. A meta-analysis of 21 case-control studies revealed that celiac disease is associated with a higher incidence of recurrent aphthous stomatitis (25% vs 11%; OR, 3.79 [95% CI, 2.67 to 5.39]; P <.001). Topical corticosteroids are first-line agents to manage recurrent aphthous stomatitis; however, systemic medications may be necessary in more severe cases. Conclusions and Relevance: Dry mouth, oral candidiasis, and recurrent aphthous ulcers are common oral conditions that may be associated with patient discomfort, decreased quality of life, and morbidity. First-line treatment includes over-the-counter sialagogues for dry mouth, topical antifungals for oral candidiasis, and topical corticosteroids for aphthous ulcers. Oral conditions that do not improve with first-line treatment may require treatment with systemic medications.

Study of oral microorganisms contributing to non-carious cervical lesions via bacterial interaction and pH regulation.

There is a lack of evidence about the relationship between microorganisms and non-carious cervical lesions (NCCLs) due to limited technologies. A group of 78 patients was enrolled for microbial 16S rRNA sequencing of dental plaques on normal and defective cervical surfaces. Parallel data from 39 patients were analysed with paired t tests, and Fusobacteriales exhibited significantly less distribution on NCCLs than on normal surfaces. As a result, Fusobacterium nucleatum, the most common oral bacterial strain belonging to the order Fusobacteriales, was selected for further research. From a scanning electron microscopy (SEM) scan, the tooth surface with Fusobacterium nucleatum and Streptococcus mutans culture was more intact than that without Fusobacterium nucleatum. Furthermore, the calcium contents in groups with Fusobacterium nucleatum were significantly higher than that without it. In further mechanistic research, Fusobacterium nucleatum was demonstrated to adhere to and disturb other organisms as well as producing alkaline secretions to neutralize the deleterious acidic environment, protecting the tooth structure. In conclusion, microorganisms and NCCLs were confirmed directly related through adherent bacterial interactions and pH regulation. The research provides a new perspective and experimental evidence for the relation between microorganisms and NCCLs, which guides clinical treatment and preventive dentistry in the future.

Novel molecular cues for dental defects in hypophosphatasia.

Mineralization disorders with a broad range of etiological factors represent a huge challenge in dental diagnosis and therapy. Hypophosphatasia (HPP) belongs to the rare diseases affecting predominantly mineralized tissues, bones and teeth, and occurs due to mutations in the ALPL gene, which encodes tissue-nonspecific alkaline phosphatase (TNAP). Here we analyzed stem cells from bone marrow (BMSCs), dental pulp (DPSCs) and periodontal ligament (PDLSCs) in the absence and presence of efficient TNAP inhibitors. The differentiation capacity, expression of surface markers, and gene expression patterns of donor-matched dental cells were compared during this in vitro study. Differentiation assays showed efficient osteogenic but low adipogenic differentiation (aD) capacity of PDLSCs and DPSCs. TNAP inhibitor treatment completely abolished the mineralization process during osteogenic differentiation (oD). RNA-seq analysis in PDLSCs, comparing oD with and without TNAP inhibitor levamisole, showed clustered regulation of candidate molecular mechanisms that putatively impaired osteogenesis and mineralization, disequilibrated ECM production and turnover, and propagated inflammation. Combined alteration of cementum formation, mineralization, and elastic attachment of teeth to cementum via elastic fibers may explain dental key problems in HPP. Using this in vitro model of TNAP deficiency in DPSCs and PDLSCs, we provide novel putative target areas for research on molecular cues for specific dental problems in HPP.

Schizophrenia and Dental Health: A Systematic Review.

ABSTRACT: Schizophrenia is characterized not only by psychopathological symptoms but also by medical comorbidities. Among the latter, there are limited data on dental health. We conducted a systematic review with the primary aim of clarifying the extent of the relationship between dental diseases and schizophrenia. The second aim was to delineate an intervention program based on illness-related factors that influence dental health. The preferred reporting items for systematic reviews and meta-analyses statement for reporting systematic reviews was used. Only articles published in English language peer-reviewed journals were considered; we excluded case reports, meta-analyses, and systematic reviews, as well as studies that did not clearly report statistical analysis, diagnostic criteria, or the number of patients included. Twenty-one studies comprising 13,110 patients with schizophrenia and 9025 healthy controls were included. Negative symptomatology, long duration of illness, smoking habit, drug-induced xerostomia, and neuroinflammation are the most critical areas. We suggest an intervention program for prevention and treatment of dental diseases in schizophrenia.

Smokeless tobacco use: its prevalence and relationships with dental symptoms, nutritional status and blood pressure among rural women in Burkina Faso.

BACKGROUND: Sub-Saharan women use smokeless tobacco (SLT) more than smoked tobacco. Among Western African countries, the estimated weighted prevalence of SLT use in rural women was found to be the highest in Burkina Faso (after Sierra Leone). This study aimed to assess the prevalence of SLT use and its associated factors among rural women in Burkina Faso by using nationally representative data. METHODS: We used data from the 2013 STEPwise approach to Surveillance (STEPS) study, which provided sociodemographic, clinical (anthropometric, systolic blood pressure [SBP], diastolic blood pressure [DBP] and dental symptoms), biological (total and high-density lipoprotein cholesterol and fasting blood sugar), and tobacco and alcohol consumption data. Data for 1730 rural women were used, and we performed Student's chi-squared and logistic regression analyses. RESULTS: The prevalence of current SLT use was 13.8% (95% CI: 12.2-15.5). Significant risks for SLT use were the presence of dental symptoms (adjusted odds ratio [aOR] = 2.59; p < 0.001), undernourishment (aOR = 1.78; p < 0.01), decreased waist circumference (aOR = 0.98; p < 0.05), decreased DBP (aOR = 0.97; p < 0.01), increased SBP (aOR = 1.01; p < 0.05), and increased differential blood pressure (aOR = 1.01; p < 0.05). The co-use of alcohol was also a significant risk factor (aOR = 2.80; p < 0.001). CONCLUSION: The prevalence of current SLT use was high among rural women in Burkina Faso, and significant concerns for users included alcohol co-use, the occurrence of dental symptoms, undernourishment, and an increase in differential blood pressure. National Public Health interventions are needed to reduce SLT use and its health-related concerns.

Oral and dental alterations and growth disruption following chemotherapy in long-term survivors of childhood malignancies.

PURPOSE: More attention has been focused on the long-term side effects of treatment protocols since impressive advances in childhood cancer treatment have resulted in a growing population of patients. The purpose of this study was to investigate the disturbances of dento-facial development in children who were long-term survivors of childhood malignancies. METHODS: Fifty-three children (mean age, 10 years + 4 months) in long-term remission underwent oral/dental and radiographic examinations after completion of therapy. Crown and root malformations, gingival/periodontal status, enamel defects, discolorations, decayed and unerupted teeth, premature apexifications, agenesis, maximal interincisal opening and lateral movement of jaws, and soft tissue abnormalities were noted. Caries were evaluated by the decayed-missing-filled teeth (DMFT) index. Forty healthy children (mean age, 12 years + 4 months) belonging to the same age group and socioeconomic community were served as controls. All participants in the study were evaluated in terms of craniofacial development. RESULTS: The data of the study showed that higher prevalence of root malformation, unerupted teeth, and enamel hypoplasia were detected as a consequence of childhood cancer and/or antineoplastic therapy. Although no differences of craniofacial growth and development were observed between groups (P > 0.05), plaque and gingival index scores were statistically higher in the study group (P < 0.05). CONCLUSION: A range of variations in dental structures is recognized as a side effect of childhood cancer therapy in long-term survivors of pediatric malignancies that may affect their quality of life.

Insula stroke: the weird and the worrisome.

Infarction of the insula is a common scenario with large tissue-volume strokes in the middle cerebral artery territory. Considered to be part of the central autonomic network, infarction of this region is associated with autonomic disturbances, in particular cardiovascular dysregulation. Risk of aspiration following stroke is also associated with involvement of the insula, consistent with its purported participation in complex functions of the mouth and pharynx. Strokes restricted to the insula are rare and present with a broad range of symptoms that offer a window of insight into the diverse functionality of the insular cortex. Chemosensory, autonomic, vestibular, auditory, somatosensory, language and oropharyngeal functional deficits are all recognised, among others. Long-term sequelae are unknown but profound symptoms, such as hemiparesis, are usually transient. Understanding the patterns of dysfunction highlighted provides the basis for future strategies to optimise stroke management on the discovery of insula involvement.

Evaluation of risk factors for oral infection with potential for spread in a 1-year cohort study.

OBJECTIVES: To determine the frequency of oral infection with potential for spread (OIPS) and behavioural risk factors in patients referred to a regional tertiary care-centre for OIPS assessment and clearance. MATERIALS AND METHODS: A database search of all referrals to the Oral and Maxillofacial Diseases unit of HUH in 2009 was performed. Of the 2807 referrals, 408 were due to a known or suspected OIPS. The electronic patient records of these patients were analysed for patient demographics, lifestyle factors, radiological findings and clinical oral findings. Risk factors for OIPS were analysed using logistic regression and using the significant factors in univariate analyses in the multivariate models. RESULTS: The mean age of the patients was 58 years. Most patients (n = 270, 66%) were referred due to upcoming cancer or other immunosuppressive therapy. The majority (n = 314, 77%) were diagnosed with one or more OIPS. In univariate analyses, smoking (OR 3.2, 95% CI 1.6-6.4; p = 0.0006), male gender (OR 1.7, 95% CI 1.1-2.8; p = 0.02), excessive alcohol use (OR 3.0, 95% 1.1-7.9; p = 0.03) and irregular dental care (OR 4.8, 95% CI 2.6-8.8; p < 0.0001) were risk factors for OIPS. However, in multivariate analyses, smoking was the only independent risk factor for OIPS (OR 3.6, 95% CI 1.2-11.8; p = 0.02). CONCLUSIONS: OIPS are common in patients referred for OIPS clearance, and smoking was identified as an independent behavioural risk factor for them. These findings highlight the burden of disease in this patient group and the importance of smoking cessation encouragement. CLINICAL RELEVANCE: To identify patients at increased risk of OIPS.

A RETROSPECTIVE STUDY OF REPORTED DISORDERS OF THE ORAL CAVITY IN LARGE FELIDS IN AUSTRALIAN ZOOS.

Disorders of the oral cavity are conditions reported by veterinarians that impact the health and welfare of large felids in human care. There have been no studies documenting the prevalence of these conditions and species affected in Australian zoos. A review of the medical records of lions (Panthera leo), tigers (Panthera tigris), cheetahs (Acinonyx jubatus), jaguars (Puma onca), snow leopards (Panthera uncia), Persian leopards (Panthera pardus saxicolor), and cougars (Puma concolor) from 10 Australian zoos and an online survey of zoo professionals from Australian and New Zealand zoos was performed to determine the recorded prevalence of disorders of the oral cavity in these species. Preliminary assessments were also made to determine if there was an association between the occurrence of tooth fractures and diet, feeding practices, species, sex, and age of the animal. The study also examined associations of these conditions with behavior, such as fighting, and husbandry practices, such as the provision of enrichment items. The review found that tooth fractures were common in tigers and lions greater than 8 yr of age. Animal caregivers attributed this to animals chewing on large, hard pieces of bone in some instances, but this could not be verified. Instances of bones being lodged between canine teeth were observed and appeared to be related to the feeding of bones of inappropriate size. Based on these findings, it is recommended that guidelines for bone size fed be developed and that animals over the age of 8 yr receive regular dental examinations under general anesthesia.

Outcome of adult patients with X-linked hypophosphatemia caused by PHEX gene mutations.

X-linked hypophosphatemia (XLH) is the most common monogenic disorder causing hypophosphatemia. This case-note review documents the clinical features and the complications of treatment in 59 adults (19 male, 40 female) with XLH. XLH is associated with a large number of private mutations; 37 different mutations in the PHEX gene were identified in this cohort, 14 of which have not been previously reported. Orthopaedic involvement requiring surgical intervention (osteotomy) was frequent. Joint replacement and decompressive laminectomy were observed in those older than 40 years. Dental disease (63%), nephrocalcinosis (42%), and hearing impairment (14%) were also common. The rarity of the disease and the large number of variants make it difficult to discern specific genotype-phenotype relationships. A new treatment, an anti-FGF23 antibody, that may affect the natural history of the disease is currently being investigated in clinical trials.

Dental and periodontal manifestations of glycogen storage diseases: a case series of 60 patients.

Glycogen storage diseases (GSDs) are rare genetic disorders of glycogen metabolism where the liver, kidneys, respiratory and cardiac muscles, as well as the immune and skeletal systems can be affected. Oral manifestations can also be present, but the specificity and frequency of these manifestations in the different forms of GSD are unknown. Analysis of a case series of 60 patients presenting four types of GSD (Ia, Ib, III, and IX) showed that the different types of GSDs have common and specific oral manifestations. In none of the GSD types studied, the prevalence of caries was higher than in the general population, especially in patients benefiting from current nutritional therapy, while in all GSD types the prevalence of delayed tooth eruption, agenesis, and tooth shape abnormalities was increased compared to the general population. Severe periodontitis prevalence was increased in patients with GSD Ib and neutropenia. Our results show that GSDs have oral manifestations and suggest some specificity depending on the type of GSDs.

Prospective evaluation of relationships between radiotherapy dose to masticatory apparatus and trismus.

AIMS: This feasibility study aimed to identify relationships between radiation doses to the masticatory apparatus as a combined block or as individual subunits with changes in trismus following radiotherapy. MATERIAL AND METHODS: Twenty patients from a single center were recruited prospectively as part of a randomized trial comparing proactive exercises in the management of trismus. Patients with stage III/IV oral cavity or oropharyngeal squamous cell cancers received intensity-modulated radiotherapy with concurrent systemic therapy. All patients had trismus prior to radiotherapy. Maximal inter-incisor distance (MID) was measured pre- and 6 months from the start of radiotherapy. Bilateral muscles of mastication: medial and lateral pterygoids (MP and LP), masseters (M), temporalis (T), temporomandibular joint (TMJ) were contoured on CT images. The block comprised all muscles excluding the TMJ below the orbital floor. Mean dose, equivalent uniform dose (EUD) and V35-V60 Gy were compared with change in MID. RESULTS: In six patients, the MID deteriorated at 6 months from the start of radiotherapy compared with 14 whose MID improved. No significant association was observed between age, gender, smoking, alcohol status, exercise compliance, cisplatin, tumor site, stage, V35-V60 Gy or EUD with change in MID. A clinical outlier was excluded. Without the outlier (n = 19), a significant association was seen between mean dose and change in MID at 6 months for the ipsilateral block (p = .01), LP (p = .04) and M (p < .01). All patients where trismus deteriorated at 6 months received mean doses >40 Gy to the block. CONCLUSION: Higher mean radiation doses to the ipsilateral block, LP and M were significantly associated with deterioration in trismus. Limiting dose to these structures to ≤40 Gy for tumors not invading the masticatory muscles may improve treatment-related sequelae. The ipsilateral block, LP and M should be studied further as possible alternative avoidance structures in radiotherapy treatment planning.

Association between the time after transplantation and different immunosuppressive medications with dental and periodontal treatment need in patients after solid organ transplantation.

OBJECTIVE: The aim of this study was to investigate the association of time after transplantation and different immunosuppressive medications with dental and periodontal treatment needs in patients after solid organ transplantation (SOT). METHODS: After lung, liver, or kidney transplantation, patients were included and divided into subgroups based on the time after SOT (0-1, 1-3, 3-6, 6-10, and >10 years) and immunosuppression (tacrolimus, cyclosporine, mycophenolate, glucocorticoids, sirolimus, and monotherapy vs combination). Dental treatment need was determined by the presence of carious lesions, while periodontal treatment need was diagnosed based on a Periodontal Screening index score of 3-4. The overall treatment need included both the dental and/or periodontal treatment needs. Statistical analysis was performed using the Kruskal-Wallis test and chi-squared test (P < .05). RESULTS: A total of 169 patients were included after SOT. A dental treatment need of 44%, a periodontal treatment need of 71%, and an overall treatment need of 84% were detected in the total cohort. Only patients with >10 years after SOT had a lower dental treatment need compared to the other groups (P = .02). All other comparisons of dental, periodontal, and overall treatment needs were comparable between subgroups depending on time since SOT. Furthermore, no statistically significant differences were found in terms of the dental, periodontal, or overall treatment needs following the administration of different immunosuppressive medications. CONCLUSION: The high treatment need of patients after SOT, irrespective of the time since transplantation, suggests insufficient dental and periodontal treatment before and maintenance after organ transplantation. Furthermore, immunosuppressive medication was not associated with the treatment need.

Elder neglect-Oral diseases and injuries.

Elder neglect (EN) is the failure of a designated caregiver to meet the needs of a dependent older person. World EN prevalence, meta-analyzed in this study, is 1.0% or 1.8% according to different statistical methods. Referring alleged EN cases to Adult Protective Services (APSs) by healthcare workers (HCWs) is mandatory in many countries. However, only few claims are substantiated, as EN could be confused with Self-Neglect, and neglect could be unintentional or due to caregiver unawareness. Screening tools are inaccurate, and their use is discouraged by public health organizations, because they lead to too many false positives, which engulf the already overwhelmed APSs. HCWs need effective tools with objective judgments, which do not hamper the HCW-caregiver-patient rapport and prevent lawsuits when allegations are unfounded. Orofacial EN manifestations (poor oral/denture hygiene, lack of needed/improper dentures, dry mouth, skin/mucosal rashes) are essential Forensic Markers of EN. I classified EN-associated oral diseases according to the unmet needs into four groups: (1) traumatic injuries due to lack of caregiver vigilance (e.g., maxillofacial fractures); (2) diseases due to oral hygiene deficiency (e.g., root caries); (3) diseases typical of the elderly with late/no diagnosis (e.g., oral cancer); and (4) diseases typical of the elderly exacerbated by psychological distress (e.g., oral lichen planus).

Effect of long-term oral appliance therapy on obstruction pattern in patients with obstructive sleep apnea.

PURPOSE: Oral appliance therapy is an alternative treatment modality for obstructive sleep apnea (OSA). However, there have been no studies to determine whether changes in the obstructive pattern occur following long-term use of oral devices. Therefore, we examined whether the obstructive pattern changes in patients with OSA who undergo long-term oral appliance therapy using drug-induced sleep endoscopy (DISE). METHODS: We investigated 156 consecutive patients diagnosed with OSA. Seventy-nine of these patients were found to be eligible for inclusion in this study. All enrolled patients underwent two DISE examinations: before and after oral appliance use. We compared the DISE findings for each patient in terms of degree and configuration of airway obstruction at the levels of the velum, oropharynx, tongue base, and epiglottis. RESULTS: We found that dental problems, as assessed using the average values of overjet and overbite, were significantly decreased after 2 years of oral appliance use. Comparisons of the DISE findings revealed that there was significant widening of the upper airway structures following long-term oral appliance therapy, especially in the velum (P = 0.022) and epiglottis (P = 0.001). However, changes in the configuration of upper airway obstruction were not observed in any of the structures of the upper airway. CONCLUSIONS: We found evidence possibly indicating decreased obstruction at the levels of the velum and epiglottis after long-term use of oral appliances. We suggest further cohort studies to confirm these findings.

Infant and baby feeding and the development of the maxillofacial complex based on own observations and the literature.

The method and technique of feeding a young child affect the shape of the maxillofacial complex. Breastfeeding is the recommended method of feeding in the first six months of life. It is encouraged to continue natural feeding in later months, simultaneously developing other food extraction techniques. The correct formation of the stomatognathic system is a result of the correct organization of the motor patterns during feeding.

ACTUAL ISSUES OF ODONTOGENIC MAXILLARY SINUSITIS (REVIEW).

Odontogenic maxillary sinusitis has now increasing incidence in dental and otorhynolaryngological practice. Its incidence varies from 10-12 % to 50-75 %, according to different authors. Literature study showed that odontogenic maxillary sinusites are mostly unilateral, and significantly differ in complaints, clinical signs, and diagnostic and treatment measures from other types of sinusitis. This should be taken into account, because often odontogenic maxillary sinusitis is misdiagnosed with common sinusitis, and only in 77 % such patients are examined by both dental specialist and otorhynolaryngologist. Study of causes of odontogenic maxillary sinusitis revealed that now iatrogenic impact prevails over other causes, which had been previously considered as main causes of odontogenic maxillary sinusitis. Especially endodontic treatment and implantation surgery are major causes of odontogenic maxillary sinusitis in present time, due to increasing incidence of perforation and damage of sinus by filling materials, bone or tooth particles, and implants. Anatomical structure of dental-sinus border area, and volume of endodontic treatment and implanting procedures, determines last ones as causative triggers due to development of complications and inflammatory processes. Microbial flora is mostly presented by anaerobic microorganisms; at the same time aerobic and fungal organisms are found in the microscopy of histology of patients with odontogenic maxillary sinusitis. At the same time, polymicrobial associations show high resistance to wide spectrum of antimicrobial medications. In past years theory of microbial biofilms is considered leading in explanation of recurrent and persistent odontogenic sinusitis. Such polymicrobial associations are covered with complex shield of different compounds, providing protection and nutrients. This significantly complicates treatments and can cause recalcitrant and recurrent infections.

Bioarchaeological profile of stress and dental disease among ancient high altitude Himalayan communities of Nepal.

OBJECTIVES: This study examines biological indicators of dental disease and nonspecific stress in human remains of three high altitude Himalayan archaeological sites to test whether shared ecological constraints led to similar bioarchaeological profiles in these markers. METHODS: Samples (n = 170) derive from three sites in Nepal dating to two periods (400-50 BCE and c. 400-650 CE). Dental diseases (caries, antemortem tooth loss, and abscesses) were assessed by both the number of individuals and the number of elements observed, while childhood stress markers included observation of growth disruptions (enamel hypoplasia and adult femur length/stature) and cranial porosities. Statistical analysis included chi-square and Fisher's exact tests for categorical data and ANOVA and t-tests for metric data. RESULTS: There are significant differences between the sites and sexes in frequencies of dental diseases in the adult samples. There are low frequencies of childhood stress markers overall and the femur length data show no significant differences across sites, but significant sexual dimorphism within each site. Females have reduced stature compared to contemporary Tibetan samples residing at a similar elevation. CONCLUSIONS: Variations in dental disease frequencies between the sites may be due to local variations in microenvironment, cultural, and/or temporal differences in resource availability, food consumption and preparation, as well as the age structure of the samples. The low frequencies of markers for nonspecific stress may be indicative of the ability of these ancient Himalayan groups to successfully meet the challenges posed by the extreme conditions of high altitude living through biocultural adaptations.

Melatonin: A Review of Its Potential Functions and Effects on Dental Diseases.

Melatonin is a hormone synthesised and secreted by the pineal gland and other organs. Its secretion, controlled by an endogenous circadian cycle, has been proven to exert immunological, anti-oxidant, and anti-inflammatory effects that can be beneficial in the treatment of certain dental diseases. This article is aimed at carrying out a review of the literature published about the use of melatonin in the dental field and summarising its potential effects. In this review article, an extensive search in different databases of scientific journals was performed with the objective of summarising all of the information published on melatonin use in dental diseases, focussing on periodontal diseases and dental implantology. Melatonin released in a natural way into the saliva, or added as an external treatment, may have important implications for dental disorders, such as periodontal disease, as well as in the osseointegration of dental implants, due to its anti-inflammatory and osseoconductive effects. Melatonin has demonstrated to have beneficial effects on dental pathologies, although further research is needed to understand the exact mechanisms of this molecule.