وزارة التعليم العالي والبحث العلمي جامعة القادسية كلية طب اﻻسنان HISTOLOGICAL STUDY FOR SALIVARY GLAND AND COMPARESION BETWEEN ADULT AND CHILD IN SOME HISTOLOGICAL STRUCTURES بحث مقدم الى كلية طب اﻻسنان كجزء من متطلبات نيل شهادة البكالوريوس تقدم به الطالبات: ندى علي حسين فرح علي عبد أطياف ماجد جميل امال عبد الكريم جريو بأشراف: الدكتورة نهى شاكر علي 1440هـ 2019 م 1 بسم هللا الرحمن الرحيم ))قالوا سبحانك ﻻ علم لنا اﻹ ما علمتنا إنك انت العليم الحكيم (( صدق هللا العلي العظيم سورة البقرة /32 2 شكر وثناء : الحمد هلل الذي ذكره شرف للذاكرين وشكره فوز للشاكرين وحمده عز للحامدين وطاعته نجاة للطائعين والصﻻة والسﻻم على خاتم اﻷنبياء والمرسلين محمد وعلى ال بيته الطيبين الطاهرين وبعد : فعن رسول هللا )صل هللا عليه واله وسلم( انه قال:من لم يشكر الناس لم يشكره هللا فبعد اﻻنتهاء من هذا البحث يطيب لي في مقام الشكر ان اسجل بأمتنان شكري وتقديري الى دكتورتي الفاضلة )الدكتورة نهى شاكر علي ( وذلك لقبولها باﻻشراف على البحث . كما أتقدم بشكري وامتناني لعائلتي وأصدقائي وزمﻻئي في الدراسة لمساندتهم لي كما اهدي شكري لكل من اعانني في دراستي سواء بالقول او الفعل او الدعاء وأخيرا فأني وان ذكرت بعض اﻷسماء دون اﻷخرى فأن ذلك ﻻ يعني عدم الوفاء والتنكر للقسم اﻻخر بل لهم مني جميعا بعد المعذرة – أكثر مما تحويه اﻷسطر وتقدمه الكلمات. اﻻهداء : 3 الى بؤرة النور التي عبرت بي نحو اﻷمل واﻷماني الجميلة واتسع قلبه ليحتوي حلمي حين ضاقت الدنيا فروض الصعاب من اجلي وسار في حلكة الدرب ليغرس معاني النور والصفاء في قلبي والدي الحبيب لقد عاش من اجلنا من اجل ان نحيا حياة كريمه في بيتا كريم وفي احضان علم نافع كريم ومن اجل ان انفذ امامه بشهاده التي تعترف كل قصاصة فيها بانه سبب جهدها , فقد كنت معنى الحياة لي وقد رضاني هللا فيك يا ابتي فهل رضيت عني الى من تتسابق الكلمات لتخرج معبرتا عن مكنون ذاتها الى التي تمتهن الحب وتغزل اﻷمن في قلب عصفورايرفرف فوق ناصية اﻻحﻻم فتبقى روحي متﻻﻷلة ومشرقة طالما كانت دعواتها عنوان دربي وتبقى امنياتي على وشك التحقق طالما يدها في يدي وسنارة جهدها وسهرها تصتاد لي الراحة وتخطف التعب واﻻلم من قلبي الى امي التي مهما كبرت سأبقى طفلتها التي تكتب اسمها على دفتر قلبهافي ساعة حزنها . CONTENT: 4 Conclusion p.7 Introduction p.8 Parotid gland p.12 Introduction p.12 Location p.15 Function p.15 Development p.16 Histology p.16 Comparesion between parotid gland in child and adult p.18 Sublingual gland p.19 Location p.20 Function p.20 Development p.21 Histology p.21 Comparesion between sublingual gland in child and adult p.21 Submandibular gland p.23 Location p.24 Function p.24 Development p.24 Histology p.25 Comparesion between submandibular gland in child and p.26 adult Minor salivary glands p.27 Location p.27 Function p.27 Development p.28 Histology p.28 Comparesion between minor salivary glands in child and p.29 adult Refrences p.30 5 Figures content Figure1 p.8 Figure2 p.9 Figure3 p.13 Figure4 p.14 Figure5 p.17 Figure6 p.18 Figure7 p.18 Figure8 p.19 Figure9 p.22 Figure10 p.23 Figure11 p.23 Abstract: Salivary glands are compound, tubuloacinar , merocrine , exocrine glands which ducts open into the oral cavity . There glands that distributed in many locations inside the oral cavity which include 800-1000 glands. Secretion of saliva is the main function emanating from salivary glands that is depend on are three pairs of major salivary glands which are parotid gland , sublingual gland , and submandibular gland and minor salivary 6 afferent stimulation (taste and mastication ). Saliva is a complex fluid composed from over 99% water , yet the small amount of additional inorganic and organic compounds (such as protein ,glycoproteins , and enzymes ) allows it to perfume many important functions . A major role is related to production of mucin , which acts as lubricant during mastication , swallowing , and speech . The mucous film protect the mucosa and keep it moist , Also it brings substances into solution so that they can tasted , and limit the activity of bacteria by causing their aggregation . Saliva contains minerals and acts as buffer , both features helps to maintain the integrity of the dental enamel . Salivary glands pass major changes during age in morphology , amount of secretions , and size , Also it may be changes due to many types of pathology . REVIEW 7 Salivary glands Introduction: Fig(1) Saliva is produced by three pairs of major salivary glands ... Parotid, Sublingual and Submandibular . as well as minor accessory glands found throughout the mucosa. Fig (2)A diagram of part of a salivary gland showing a serous acinus and mixed serous-mucous acinus. 8 Salivary glands are made up of secretory acini (acini - means a rounded secretory unit) and ducts. There are two types of secretions - serous and mucous. The acini can either be serous, mucous, or a mixture of serous and mucous. A serous acinus secretes proteins in an isotonic watery fluid. A mucous acinuss secretes secretesmucin – lubricant. In a mixed serous-mucous acinus, the serous acinus forms a serous demilune around mucous acinus,The secretory units merge into intercalated ducts, which are lined by simple low cuboidal epithelium, and surrounded by myoepithelial cells. These ducts continue on as striated ducts. These have a folded basal membrane, to enable active transport of substances out of the duct. Water resorption, and ion secretion takes place in the striated ducts, to make saliva hypotonic (reduced Na,Cl ions and increased carbonate, and potassium ions).The striated ducts lead into interlobular (excretory) ducts, lined with a tall columnar epithelium.The glands are divided into lobules by connective tissue septa. Each lobule contains numerous secretory units, or acini. Aging of salivary glands show some structural changes, such as: 1- Decrease in volume of acinar tissue. 2- Increase in fibrous tissue. 3- Increase in adipose tissue. 4- Ductal hyperplasia and dilation. 5- In addition, there are also changes in salivary contents: A- Decrease in concentration of secretory IgA. B- Decrease in the amount of mucin. 9 However, there is no overall change in the amount of saliva secreted. And Salivary glands secrete saliva which has many benefits for the oral cavity and health in general. These benefits include: -Protection: Saliva consists of proteins (for example; mucins) that lubricate and protect both the soft and hard tissues of the oral cavity. Mucins are the principal organic constituents of mucus, the slimy visco-elastic material that coats all mucosal surfaces. -Buffering(6): In general, the higher the saliva flow rate, the faster the clearance and the higher the buffer capacity, hence better protection from dental caries. Therefore, people with a slower rate of saliva secretion, combined with a low buffer capacity, have lessened salivary protection against microbes. -Pellicle formation: Saliva forms a pellicle on the surface of the tooth to prevent wearing. The film contains mucins and proline-rich glycoprotein from the saliva. The proteins (statherin and proline-rich proteins) within the salivary pellicle inhibit demineralization and promote remineralization by attracting calcium ions. -Maintenance of tooth integrity: Demineralization occurs when enamel disintegrates due to the presence of acid. When this occurs, the buffering capacity effect of saliva (increases saliva flow rate) inhibits demineralization. Saliva can then begin to promote the 10 remineralization of the tooth by strengthening the enamel with calcium and phosphate minerals. -Antimicrobial action: Saliva can prevent microbial growth based on the elements it contains. For example, lactoferrin in saliva binds naturally with iron. Since iron is a major component of bacterial cell walls, removal of iron breaks down the cell wall, which in turn breaks down the bacteria. Antimicrobial peptides such as histatins inhibit the growth of Candida albicans and Streptococcus mutans. Salivary Immunoglobulin A serves to aggregate oral bacteria such as S. mutans and prevent the formation of dental plaque. -Tissue repair(9): Saliva can encourage soft tissue repair by decreasing clotting time and increasing wound contraction. -Digestion: Saliva contains the enzyme amylase, which hydrolyses starch into maltose and dextrin. As a result, saliva allows digestion to occur before the food reaches the stomach(16). -Taste(12): Saliva acts as a solvent in which solid particles can dissolve in and enter the taste buds through oral mucosa located on the tongue. These taste buds are found within foliate and circumvallate papillae, where minor salivary glands secrete saliva(10) . REVIEW 11 1-Parotid gland : Introduction: The parotid gland is the largest major salivary gland. The parotid is 5.8 cm craniocaudally and 3.4cm ventrodor- sally. It weighs between 14 and 28 grams. The main excretory duct, Stensen’s duct measures 4–6cm in length and 5 mm in diameter. A small portion of the parotid generally accompanies the duct forming an accessory gland, a few millimeter anterior to the superficial portion of the gland. The parotid gland receives its blood supply from the branches of the external carotid artery as they pass through the gland. The parasympathetic nerve supply is derived mainly from the ninth cranial nerve reaching the gland via the otic ganglion and the auriculotemporal nerve. The sympathetic innervation of all salivary glands is provided by the postganglionic fibers from the superior cervical ganglion and reaches the individual gland in association with their vascular supply. The lymphatic drainage is via paraparotid and intraparotid lymph nodes into the superficial and deep cervical lymph nodes. The parotid gland is enclosed in a well defined connective tissue capsule which sends septa into the gland, separating it into lobes and lobules. The parotid gland is a pure serous gland ; all the acinar cells. The parotid gland is a pure serous gland ; all the acinarcells are similar in structure to the serous cells described earlier.