91吃瓜

Dental caries; Tooth decay; Streptococcus mutans; Demineralization; Remineralization; Oral hygiene; Fluoride therapy; Preventive dentistry; Caries risk assessment; Restorative treatment

Introduction

Dental caries is a multifactorial disease resulting from the interplay between oral bacteria, dietary sugars, and host factors such as saliva and tooth structure [1]. It manifests as localized destruction of the tooth enamel, dentin, and cementum, which, if left untreated, can lead to pain, infection, and tooth loss [2]. The World Health Organization identifies dental caries as a major global health issue affecting 60-90% of school children and nearly 100% of adults. Dental caries remains one of the most widespread and persistent oral health issues affecting millions globally, irrespective of age, gender, or socioeconomic status [3]. As a multifactorial and progressive disease, caries involves the localized destruction of dental hard tissues, primarily enamel and dentin, resulting from the metabolic activities of specific cariogenic bacteria within the dental biofilm. Although widely considered preventable, dental caries continues to impose a significant burden on healthcare systems, contributing to pain, tooth loss, impaired function, and reduced quality of life in both children and adults [4].

The development of caries is influenced by a convergence of factors including dietary habits especially frequent consumption of fermentable sugars, oral hygiene practices, salivary flow and composition, host immune response, and microbial composition of the oral cavity [5]. Central to the disease process is the dynamic interaction between acidogenic bacteria such as Streptococcus mutans, the availability of fermentable carbohydrates, and the tooth surface [6]. The resulting acidic environment favors demineralization of enamel and dentin, tipping the balance away from natural remineralization processes and promoting lesion progression.

Understanding the epidemiology and etiology of dental caries is crucial for implementing effective prevention and treatment strategies [7]. Over the decades, the focus of caries management has evolved from the traditional surgical-restorative approach to a more conservative and preventive model rooted in risk assessment, behavior modification, and early intervention. Public health efforts, such as community water fluoridation and school-based dental programs, have significantly reduced caries prevalence in many regions, yet disparities persist, particularly among low-income and rural populations [8]. Emphasis is placed on the biological mechanisms of caries formation, the importance of early detection and minimally invasive care, and the role of interdisciplinary approaches in promoting oral health. By synthesizing current scientific knowledge and clinical practice, this work contributes to a holistic understanding of caries as not merely a disease of the tooth, but a manifestation of broader behavioral, environmental, and systemic influences.

Etiology and pathogenesis

The primary etiological agents are Streptococcus mutans and Lactobacillus species. These bacteria metabolize
fermentable carbohydrates to produce acids. The acid lowers the pH in the oral cavity below 5.5, leading to the
demineralization of the enamel. Saliva plays a vital role in neutralizing acids and supplying minerals like calcium and phosphate. Fluoride enhances remineralization and inhibits bacterial metabolism.

Repeated acid attacks without sufficient remineralization lead to the breakdown of enamel and exposure of the dentin, causing sensitivity and eventual cavitation.

Risk factors

Several factors contribute to the susceptibility of an individual to dental caries:

Diet: Frequent consumption of sugary or acidic foods and drinks.

Oral hygiene: Poor brushing and flossing habits.

Salivary flow: Xerostomia (dry mouth) reduces protective effects of saliva.

Fluoride exposure: Inadequate fluoride reduces enamel resistance.

Socioeconomic status: Limited access to dental care and education.

Genetics: Tooth morphology and saliva composition may be hereditary.

Caries can be asymptomatic in the early stages and may only be detectable via radiographs or visual inspection. As the lesion progresses, signs may include:

• White spot lesions (initial enamel demineralization)
• Brown or black spots (advanced demineralization)
• Cavities or holes in teeth
• Tooth sensitivity or pain
• Bad breath (halitosis)
• Swelling or abscess in severe cases

Diagnosis

Visual and Tactile Examination: Using dental explorers and mirrors.

Radiographic Imaging: Bitewing X-rays are most effective in detecting interproximal caries.

Laser Fluorescence Devices: Tools like DIAGNOdent detect early lesions.

Fiber Optic Transillumination (FOTI): Helps detect cracks and early decay.

Prevention remains the cornerstone of dental caries management:

Fluoridated water and toothpaste.

Professional topical applications like varnishes and gels.

Brushing twice daily with fluoride toothpaste.

Daily flossing to clean interproximal areas.

Dietary modifications

Limiting sugar intake.

Encouraging fibrous fruits and vegetables.

Protective coatings on molars to prevent food and bacteria accumulation.

Community dental health programs.

School-based fluoride and sealant initiatives.

Treatment depends on the stage of caries:

Remineralization using fluoride or calcium phosphate agents.

Monitoring and dietary counseling.

Restorative dentistry, use of amalgam or composite resin fillings.

Endodontic therapy, for caries involving the pulp.

Extractions, when the tooth is beyond repair.

Atraumatic Restorative Treatment (ART).

Silver diamine fluoride (SDF) application to arrest decay.

Complications of untreated caries

Neglecting dental caries can result in:

Severe toothache and discomfort

Abscess formation and cellulitis

Tooth loss

Nutritional problems due to difficulty in eating

Impact on self-esteem and social interaction

Systemic infections in rare cases (e.g., Ludwig’s angina, endocarditis)

Dental caries in children

Early Childhood Caries (ECC) is a specific form of caries affecting children under six years. It is often associated with frequent bottle-feeding with sugary liquids. Prevention includes:

Avoiding bedtime bottles with milk or juice.

Initiating dental visits by the first birthday.

Parental education and regular fluoride applications.

Advancements in biotechnology and diagnostics are paving the way for novel caries prevention and management approaches:

Probiotic therapies to alter oral microbiota.

Biomimetic remineralization agents that mimic natural enamel.

Vaccines targeting Streptococcus mutans (under development).

Artificial intelligence in caries detection and risk prediction.

Conclusion

Dental caries is a preventable disease that requires a multifaceted approach encompassing education, prevention, early detection, and effective treatment. With growing awareness and access to dental care, it is possible to reduce the global burden of tooth decay and improve overall oral health outcomes. Public health policies must integrate dental care as a vital component of general health promotion.