Congenital aplasia of the major salivary glands: literature review and case report

Congenital aplasia of the major salivary glands is rare, and there have been few cases of the condition reported to date. In many cases, absence of the salivary glands is associated with syndromes involving the ectodermal tissues. The xerostomia encountered in affected children is usually associated with increased risk for caries and infections of the soft tissues. The purpose of this paper was to describe the case of a 10-year-old boy with bilateral aplasia of the submandibular and parotid salivary glands and the preventive and restorative treatment rendered. This case study demonstrates the importance of timely diagnosis of this condition in order to prevent the serious oral complications from xerostomia.     

Aplasia of the parotid gland in Down syndrome

Salivary gland aplasia has not to our knowledge been previously reported in association with Down syndrome. We present a case of bilateral parotid aplasia in a patient with Down syndrome. Clinically he had aplasia of the major salivary glands and symptoms of xerostomia. Thirteen other family members over three generations were examined, and all had functional parotid glands. We reviewed publications about Down syndrome and salivary aplasia, together with the data regarding his other clinical problems and family background. His oral problems were inadequate plaque control, dental caries, and erosion of the teeth.     

Salivary gland aplasia: an ectodermal disorder?

A case of a patient presenting with the symptoms of lifelong xerostomia is discussed. Clinical investigation demonstrated aplasia of all the major salivary glands, lacrimal gland hypoplasia and enamel hypoplasia. The management and aetiology of the case is discussed.     

Salivary gland aplasia with cleft lip and palate: a case report and review of the literature.

We report the case of a patient with lifelong symptoms of xerostomia and a repaired bilateral cleft lip and palate. The clinical evaluation demonstrated aplasia of the major salivary glands. A review of the literature pertaining to salivary gland aplasia is presented, along with a summary of the data regarding patient gender, defect sites, hereditary background, and combined manifestations. The diagnostic methods, possible pathogenesis, and management are also discussed.     

Salivary gland aplasia: an ectodermal disorder?

Abstract A case of a patient presenting with the symptoms of lifelong xerostomia is discussed. Clinical investigation demonstrated aplasia of all the major salivary glands, lacrimal gland hypoplasia and enamel hypoplasia. The management and aetiology of The case is discussed.     

An unusual pattern of dental damage with salivary gland aplasia

BACKGROUND: Dental destruction can develop from numerous causes. Major salivary gland aplasia is an uncommon causative factor. The resulting xerostomia can lead to extensive dental demineralization. CASE DESCRIPTION: The author examined a 19-year-old man because of the patient's concern regarding decreased salivary volume and his dental condition. There was extensive loss of tooth structure and an astonishing pattern of dental destruction most notable on the palatal portions of the maxillary molars and premolars that is best described as "chipping." It was only after taking the patient's history, clinically examining the patient and conducting a radioisotope study that the author was able to make a confident diagnosis of the absence of four major salivary glands. CLINICAL IMPLICATIONS: Dentists should be aware that salivary gland aplasia is an uncommon cause of dental deterioration. It may manifest itself not by extensive caries but by a dental chipping effect. Early recognition and a therapeutic strategy can prevent progressive dental damage.     

Bilateral parotid glands aplasia: a case report and literature review

Objectives

Bilateral parotid gland aplasia is a rare congenital anomaly that almost consistently leads to xerostomia and caries. It is often associated with other congenital craniofacial abnormalities. The objective was to describe a case with asymptomatic bilateral parotid gland aplasia and to review previously reported cases.

Methods

Panoramic radiograph, computed tomography and magnetic resonance imaging were obtained and an in-depth assessment of patient’s dental status and sequence analysis of FGF10, FGFR2 and FGFR3 genes were performed. Previous reports of bilateral parotid gland aplasia were assessed.

Results

In a 64-year-old woman with extensive basal cell carcinoma of nasal skin an incidental bilateral parotid gland aplasia was noted during radiotherapy treatment planning. Dental status revealed surprisingly numerous (n?=?15) teeth without active caries lesions. No other craniofacial abnormalities were identified. To rule out most probable syndromes associated with parotid gland aplasia, sequence analysis of FGF10, FGFR2 and FGFR3 genes was performed showing no pathogenic variants. With a literature review, we identified 148 cases of salivary gland aplasia in which median age at diagnosis was 21 years and one third were asymptomatic. In only 10 of these cases, the patients presented with bilateral aplasia of parotid glands without other craniofacial abnormalities.

Conclusions

Absence of salivary glands can have a debilitating effect on oral health and is often accompanied by other craniofacial abnormalities. However, relatively frequent asymptomatic course suggests that this rare malformation is probably underdiagnosed. Therefore, we propose systematic reporting of salivary gland aplasia to assess its true prevalence in general population.

     

Salivary gland function in persons with ectodermal dysplasias

Ectodermal dysplasias (EDs) constitute a group of conditions comprising developmental defects in two or more of the following tissues: hair, teeth, nails, and sweat glands. The aim of the present study was to contribute to a better understanding of salivary gland involvement in EDs. An ED group (n = 39, median age 12 yr; 24 males, 15 females) and a healthy age- and sex-matched control group were studied. Citric acid stimulated submandibular and parotid salivary flow rates and salivary concentrations, and output of total protein, acidic proline-rich proteins and histatins were analysed. The associations between quantitative and qualitative salivary parameters were also studied. In the ED group, 13 persons (33%) demonstrated a significantly reduced secretion of submandibular and/or parotid saliva, in addition to a low unstimulated and/or chewing-stimulated whole salivary flow. In the ED group as a whole, a reduced median secretory rate of submandibular saliva was found, whereas the median concentrations of some protein parameters were increased. However, the overall output of proteins was normal or reduced. Submandibular glands seemed to be more affected than parotid glands in EDs. In conclusion, salivary secretory tests are recommended in persons with known or suspected EDs.     

外胚叶发生不全发病机制的研究进展

外胚叶发生不全(ED)是一种遗传性疾病,主要表现为牙齿、毛发、指甲和汗腺等外胚叶组织发生不全,其发病的内因主要是单基因突变.目前已经发现逾200种不同类型的基因突变,来自不同的染色体,或同一染色体上编码不同蛋白质的基因.其临床表现多种多样,且不同基因突变个体的临床表现往往不同;即使是同一基因不同类型的突变,其临床表现都可能大相径庭.本文就ED的发病机制及基因治疗进展作一综述,以利于加深临床医生对该疾病的认识并为进一步基因治疗研究提供帮助.     

Xerostomia. Diagnosis and treatment

Comprehensive examination and treatment were made of 57 patients with xerostomia on the background of different salivary glands diseases. Mexidol was used for treatment in the form of external blockade in the region of the salivary glands. Expressed clinical effect was observed in 67% of patients with considerable reduction or disappearance of oral cavity xerostomia, decrease of glands swelling and general condition improvement. Indices of lipid peroxidation and of antioxidant protection of mixed saliva of xerostomic patients differed from analogous control data and depended upon the type of xerostomia involved.     

Saliva and intensity modulated radiotherapy

A dry mouth (xerostomia) is a serious side effect for head and neck cancer patients treated with radiotherapy. The degree of xerostomia is dependent on the dosage in the parotid glands. New, advanced radiation techniques, such as intensity-modulated radiotherapy, can reduce the dosage in the parotid glands, resulting in a significant improvement in the functioning of these glands by comparison with conventional radiation techniques.     

Bilateral parotid gland aplasia

Bilateral parotid gland aplasia is a cause of xerostomia. A case is presented in which the clinical diagnosis was confirmed with the use of 99mTcO-4 salivary gland scintiscanning and computerised tomography. The literature of this rare condition is reviewed and significance to the patient discussed.     

Xerostomia—a complication of ageing*

This paper reviews the physiological and histological changes in salivary glands associated with ageing and concludes that there is no evidence to show that xerostomia is likely to result from the ageing process alone. The signs and symptoms of xerostomia are discussed. The four main factors causing xerostomia are presented and it can be seen that the condition is a side effect of diseases and the drugs used to treat these diseases. A multifaceted approach to treating xerostomia is presented and illustrated with case histories.     

Intensity-modulated radiation therapy and xerostomia

Conformal radiation with intensity-modulated radiation therapy, IMRT, is a radiation technique that potentially can minimize the dose to salivary glands and thereby decrease the incidence of xerostomia. Precise target determination and delineation is most important when using salivary gland-sparing techniques of IMRT. The reduction of xerostomia may be achieved by sparing the salivary glands on the noninvolved oral cavity and keeping the mean parotid gland dose of < 26-30 Gy if the treatment of disease is not compromised and parotid function preservation is desired.     

Six‐Year Survival of a Mini Dental Implant‐Retained Overdenture in a Child with Ectodermal Dysplasia

Patients with ectodermal dysplasia (ED) experience several problems caused by abnormal development and functioning of the head and neck region. In addition to developmental nasal cartilage abnormalities and absence of sweat glands, hair, and eyebrows, edentulism or developmental disorders of teeth (cone‐shaped teeth) are commonly observed in these types of patients. ED is also characterized by underdeveloped alveolar ridges, a decreased occlusal vertical dimension, reduced salivary secretion, and dry oral mucosa, which make prosthetic rehabilitation difficult. Few studies of intraosseous dental implant‐retained prostheses have described adverse effects on craniofacial growth and esthetic and functional disadvantages, while some researchers have described the advantages of this treatment option as an alternative option in these cases. Due to the associated alveolar bone deficiency, dental mini‐implant therapy may be a treatment option for these patients; however, there are isolated cases in the literature regarding the rehabilitation of ED patients with mini‐implant‐supported overdentures. This clinical report describes the rehabilitation of a 6‐year‐old child with ED using a maxillary removable partial prosthesis and a mini‐implant‐retained mandibular overdenture. The clinical and radiographic findings of this prosthetic rehabilitation during the 6‐year follow‐up are also presented.     

Hyposalivation in a 16‐year‐old girl: a case of salivary gland aplasia

Salivary gland aplasia is a rare condition with only a small number of cases reported worldwide. It is more commonly seen in males and can occur either in isolation or association with other defects or syndromes. It may or may not occur with a hereditary background. Scant literature exists detailing the status of sublingual salivary glands in patients with any form of major salivary gland aplasia. This case report describes the clinical and magnetic resonance imaging presentation of a 16‐year‐old girl with major salivary gland aplasia detailing the status of all six major salivary glands.     

Relationship of cytomegalovirus to salivary gland dysfunction in HIV-infected patients

In a previous retrospective study of HIV-infected patients we detected a relationship between xerostomia and the presence of cytomegalovirus in saliva. This prospective study compares 13 patients with HIV and a complaint of xerostomia and low salivary flow rates with a control group of 7 patients with HIV without xerostomia and normal salivary flow rates. Both groups were evaluated for the presence of cytomegalovirus in saliva, peripheral blood mononuclear cells, and labial minor salivary glands. Viral cultures, polymerase chain reaction, and histopathologic examination were used to detect cytomegalovirus. Xerostomia and low salivary flow rates were associated with the presence of CMV in saliva. The virus was detected in 10 of 13 xerostomia patients and 2 of 7 controls (p = 0.05, Fisher's exact test). Cytomegalovirus was detected in the saliva of patients who did not also have it in their blood suggesting a local source of virus replication such as the salivary glands. The minor salivary glands were not a major site of cytomegalovirus. Culture was more sensitive then polymerase chain reaction in detecting salivary cytomegalovirus as a result of the presence of inhibitors to the reaction in saliva. These results suggest a link between cytomegalovirus in saliva and salivary gland dysfunction in HIV-infected patients.     

Oligodontia is associated with extra-oral ectodermal symptoms and low whole salivary flow rates

INTRODUCTION: Ectodermal dysplasias (EDs) involve abnormal development of hair, teeth, nails, and sweat glands. OBJECTIVES: (1) To investigate the frequency of extraoral ectodermal symptoms in persons with oligodontia (>6 congenitally missing teeth). (2) To examine whole salivary flow rates in oligodontia patients, with special emphasis on persons with EDs. SURVEY GROUP AND METHODS: Sixty-eight persons with oligodontia and 39 healthy control persons were included. All participants underwent an interview, general and oral examinations, and whole salivary secretory tests. RESULTS: Thirty-nine (57%) of the oligodontia patients had disturbances in either hair, nails and/or sweat production in addition to teeth and were classified as the ED group. The remaining 29 oligodontia patients had no obvious signs of EDs (non-ED group). The prevalences of dry skin, asthma and eczema were higher, and whole salivary secretory rates lower, in the ED group as compared to the control group. Intermediate values were observed in the non-ED group. Incisors, canines and molars were more frequently missing in the ED group than in the non-ED group, whereas no differences were observed in the frequency of missing premolars. Negative correlations between the number of missing teeth and unstimulated and chewing stimulated whole salivary secretory rates were found.     

Transplantation of vascularized submandibular gland in dogs.

PURPOSE: Presently, treatments for xerostomia only target symptoms, as an active therapy method has not been established. Herein, we discuss the possibility of using a submandibular gland allograft technique for the disease. MATERIALS AND METHODS: Using a vascularized submandibular gland transplantation method, we extracted portions of the submandibular gland, including the duct and chorda tympani branches, from beagle dogs and placed them into the submental region of age- and weight-matched dogs. We then measured the amount of saliva secretion and examined the grafted glands histologically. RESULTS: Sufficient quantities of saliva were secreted from the grafted glands with pilocarpine treatment. Histologic findings showed that the acinar cells in the grafted and untreated contralateral glands had some atrophy, as compared with the normal glands; however, periodic acid Schiff staining showed that they produced saliva. CONCLUSIONS: Transplantation of vascularized submandibular glands into dogs was successful and may become a novel treatment strategy for patients with xerostomia.