龋齿的病因和预防

nullnull－来自加拿大。1977年，多伦多大学口腔外科学博士 为加拿大北极圈的居民服务。 －纽约罗彻斯特大学——普通牙科学博士后（Eastman牙科中心）；牙科全科住院医（Genesee医院） －在澳大利亚和新西兰作Flying Dentist，为边远地区居民服务。 －1984年，香港大学牙科学院传统牙科学系讲师，牙科学硕士。香港医学科学院，口腔外科研究员；香港口腔外科学院口腔修复科研究员。 －1994年，回到加拿大，建立私人家庭科诊所。 －2001年至今，在北京和睦家医院工作。 －广泛掌握各种牙科治疗技术。协助建立北京国际牙科研究俱乐部。加拿大牙科协会，香港牙科协会，骨整合学会，国际口腔修复学院的成员 －语言：英语，普通话，广东话Dr Tse 简介General and Family Medicine Review Conference Capital Union Medical College October 23, 2008General and Family Medicine Review Conference Capital Union Medical College October 23, 2008 Etiology and Prevention of Dental Caries Chung-Ming Tse DDS Chair / Prosthodontist Department of Dentistry Beijing United Family Hospital and ClinicsAetiology and Prevention of Dental CariesAetiology and Prevention of Dental CariesOutline: Clinical views of dental caries Aetilogy of dental caries and its cariogenic factors Caries risk factors Prevention of dental caries Pit & fissure sealants Initial caries - white lesionsInitial caries - white lesionsProximal cariesProximal cariesRampant caries – permanent dentition Rampant caries – permanent dentition Root caries in patient with xerostomiaRoot caries in patient with xerostomiaRoot caries in patient with xerostomiaRoot caries in patient with xerostomiaRampant Caries – primary dentitionRampant Caries – primary dentitionEtiology of Dental Caries 龋病病因 Etiology of Dental Caries 龋病病因 Current Theory by Newbrum (1978) 4 Factors must co-exist simultaneously: 龋病四因素理论: I. Host (tooth) 宿主 (牙齿) II. Bacteria 细菌 III. Carbohydrates 碳水化合物 IV. Time 时間 I. Host Factor 宿主因素I. Host Factor 宿主因素1. Teeth 牙齿 2. Saliva 唾液 Human behaviour and lifestyle 人的行为和生活方式I. Host Factor 宿主因素I. Host Factor 宿主因素 1. Teeth 牙齿 Normal developmental defect 正常发育的缺陷 Abnormal developmental defect 异常发育缺陷 Local inflammation 局部炎症 Iatrogenic reason 医原性原因 Environmental reason 环境原因 I. Host Factor 宿主因素I. Host Factor 宿主因素 2. Saliva 唾液 Cleansing of oral cavity 清洁口腔 Inhibition of Microorganism 抑制微生物 Anti-acid effect 抗酸作用 Remineralization effect 再矿化作用I. Host Factor 宿主因素I. Host Factor 宿主因素3. Human behaviour and lifestyleII. Bacterial Factor 细菌因素II. Bacterial Factor 细菌因素Three hypothesis 三种主张: 1. The specific plaque hypothesis 特已异性菌斑学说 2. The non-specific plaque hypothesis 非特已异性菌斑学说 3. The ecological plaque theory 菌斑生态学说 II. Bacterial Factor 细菌因素 II. Bacterial Factor 细菌因素 Pathogens 致病菌 Streptococcus mutans group 变形链球菌群 Lactobacillus 乳酸杆菌 Actinomyces 放线菌 4. Other cariogenic bacteria 其他致病龋菌 The virulence effect of the cariogenic bacteria 致病菌毒性作用The virulence effect of the cariogenic bacteria 致病菌毒性作用 Adhesion 粘附 Involve specific molecular interaction between components on the microbial cell surface adhesion and receptors in the acquired pellicle. Acidogenicity 产酸 Ability to rapidly metabolize carbohydrates to lactic, acetic and formic acid. Acid tolerance 耐酸 Ability to survive in low acidity environment.III. Dietary factor 食物因素III. Dietary factor 食物因素 Nutrient type and dental caries 营养的种类与龋病 2. Carbohydrate food and dental caries 碳水化合物食物与齿龋病 3. Frequency of eating sugar and caries 糖的食用频率与龋病 4. Nutrient and dental caries during teeth develpoment 牙齿发育期营养与龋病III. Dietary factor 食物因素III. Dietary factor 食物因素Nutrient type and dental caries 营养的种类与龋病 Endogenous nutrients 內源性营养 : Salivary secretion and gingival crevicular fluid, contains aminoacid, peptide, protein glycoprotein and trace elements. Exogenous nutrients 外源性营养 : Diet. III. Dietary factor 食物因素III. Dietary factor 食物因素Carbohydrate food and dental caries 碳水化合物食物与龋病 Many sweet foods are composed of mono or disaccharide (glucose or sucrose) which are easily metabolized by plaque bacteria and predispose enamel to dental caries. Sugar substitutes (mannital, sorbitol and xylitol) cannot be metabolized by plaque bacteria and therefore can reduce caries. III. Dietary factor 食物因素III. Dietary factor 食物因素Frequency of eating sugar and caries 糖的食用频率与龋病 Limit carbohydrate intake to main meal only.III. Dietary factor 食物因素III. Dietary factor 食物因素Nutrient and dental caries during teeth development 牙齿发育期营养与龋病IV. Time Factor 时间因素，IV. Time Factor 时间因素，The carious process consists of alternating periods of repair. The saliva has the ability to delay progression of lesions. When saliva is present, caries does not destroy the tooth in days or weeks but rather in months or years, or not at all.Prevention of Dental Caries 龋病预防Prevention of Dental Caries 龋病预防Plaque control 菌斑控制 Sugar substitutes 糖替代品 Reinforcing host’s resistance to caries 增強宿主的抵抗力 Fissure sealant 窝沟封闭I. Plaque control 菌斑控制I. Plaque control 菌斑控制Mechanical methods 机械方法 Antimicrobial agents 抗菌剂 Enzymes 酶类 Anti-adherence agents 抗菌斑附着剂 Fluorides 氟化物 Replacement therapy 替代疗法 Vaccines 疫苗I. Plaque control 菌斑控制I. Plaque control 菌斑控制Mechanical methods 机械方法 Include: tooth brush, tooth paste, dental floss, interdental tooth brush, etc. 包括有牙刷, 牙膏, 牙线, 牙簽, 牙間刷等. Basic principle: maximun removal of dental plaque, minimal damage to the teeth and gingiva. 基本原則: 最大限度清除牙表面菌斑, 減少对牙表面磨损及牙龈顶伤. I. Plaque control 菌斑控制I. Plaque control 菌斑控制Antimicrobial agents 抗菌剂 Bactericidal agents 杀菌剂 E.g. Chlorhexidin 氯己定/洗必太 Plant extracts 植物提取物 Bacteriotatic, added to mouth wash or tooth paste 抑制细菌作同, 多为漱口剂及 牙膏I. Plaque control 菌斑控制I. Plaque control 菌斑控制3. Enzymes 酶类 Specific enzymes 特异性酶 e.g. Mutanase 变聚糖酶 Glucanase 葡聚糖酶 Non-specific enzymes 非特异性酶 I. Plaque control 菌斑控制I. Plaque control 菌斑控制4. Anti-adherence agents 抗菌斑附着剂 E.g. Tea polyphenols 茶多酚 Added to mouthwash E.g. Chitosan 甲売胺 Added to tooth paste of mouthwashPlaque control 菌斑控制Plaque control 菌斑控制5. Fluorides 氟化物 Forms fluoroapatite 氟羟基磷灰石 Enhance remineralization 促进再矿化I. Plaque control 菌斑控制I. Plaque control 菌斑控制6. Replacement therapy 替代疗法 Plaque control 菌斑控制Plaque control 菌斑控制7. Vaccine 疫苗 Experimental stage 还处在研制阶段 Sugar substitues 糖替代品 Sugar substitues 糖替代品 Intense type: sweeter than sucrose e.g. saccharin, aspartame 高甜度代用品: 比蔗糖甜若干倍 糖精, 天冬苯西二肽脂 Bulk type: not as sweet e.g. xylitol, sorbitol, mannitol 低甜度代用品: 木糖醇, 山梨醇, 甘露醇III. Reinforcing Host’s Resistance to Caries 增強宿立的抵抗力III. Reinforcing Host’s Resistance to Caries 增強宿立的抵抗力Reinforcing oral care for pregnant women, infants and toddlers Reinforcing oral are for children and adolescents Establishing oral health care networkIV. Fissure Sealant 窝沟封闭IV. Fissure Sealant 窝沟封闭Evidence-based clinical recommendations for the use of pit-and –fissure sealants A Report of the American Dental Association Council on Scientific Affairs JADA 2008; 139(3):257-267IV. Fissure SealantIV. Fissure SealantPlacement of resin-based sealants on the permanent molars of children and adolescents is effective for caries prevention Reduction of caries incidence in children and adolescents after placement of resin-based sealants ranges from 86% at one year to 78.6% at two years and 58.6% at four years. Sealants are effective in reducing occlusal caries incidence in permanent first molars of children, with caries reduction of 76.3% at four years. Caries reduction is 65% at nine years from initial treatment, with no reapplication during the last five years.IV. Fissure SealantIV. Fissure SealantPit-and-fissure sealants are retained on primary molars at a rate of 74.0 to 76.5% at 2.8 years. Placement of sealants on first and second permanent molars in children and adolescents is associated with reduction in the subsequent provision of restorative services. Sealed permanent molars are less likely to receive restorative treatment. The time between receiving sealants and receiving restorative treatment is greater. The restorations are less extensive than those in permanent molars that are not sealed.Aetiology and Prevention of Dental CariesAetiology and Prevention of Dental CariesSummary: Cariogenic factors Risk factors Micro flora Increase proportion of cariogenic bacteria in plaque The plaque pH is below the critical pH Increase proportion of aciduric bacteria Host Exposed cementum surface of the root Growth defect of the tooth Young permanent teeth Reduced salivary flow Food Frequent intake of carbohydrate food Time Long time accumulation of plaque on tooth surfaceAetiology and Prevention of Dental CariesAetiology and Prevention of Dental CariesSummary: Cariogenic factors Preventive methods Micro flora Good Oral Hygiene Application of anti-microbial agents The use of replacement therapy The use of vaccines Host Promotion of remineralization Use of pit & fissure sealant Use of plaque inhibitory varnishes Improvement of salivary flow Food Avoidance of excess carbohydrate food Use of sugar substitutes Time Avoidance of frequent consumption of sweets Timely removal of plaque