Prognosis of Dental Implants in Patients With Primary Sjögren's Syndrome

Inclusion Criteria: * \- Age 20-70 years * Indication of tooth replacement with implant-supported fixed dentures * The test group should be without any potentially associated disease * pSS must be diagnosed according to the American-European Consensus Group criteria (Vitali et al., 2002): 1. The presence of any 4 of the following 6 items, as long as either item IV (Histopathology) or VI (Serology) is positive 2. The presence of any 3 of the 4 objective criteria items (that is, items III, IV, V, VI) The items: I. Ocular symptoms: a positive response to at least one of the following questions: 1. Have you had daily, persistent, troublesome dry eyes for more than 3 months? 2. Do you have a recurrent sensation of sand or gravel in the eyes? 3. Do you use tear substitutes more than 3 times a day? II. Oral symptoms: a positive response to at least one of the following questions: 1. Have you had a daily feeling of dry mouth for more than 3 months? 2. Have you had recurrently or persistently swollen salivary glands as an adult? 3. Do you frequently drink liquids to aid in swallowing dry food? III. Ocular signs --that is, objective evidence of ocular involvement defined as a positive result for at least one of the following two tests: 1. Schirmer's I test, performed without anaesthesia (\<5 mm in 5 minutes) 2. Rose bengal score or other ocular dye score (\>4 according to van Bijsterveld's scoring system) IV. Histopathology: In minor salivary glands (obtained through normal-appearing mucosa) focal lymphocytic sialoadenitis, evaluated by an expert histopathologist, with a focus score \>1, defined as a number of lymphocytic foci (which are adjacent to normal-appearing mucous acini and contain more than 50 lymphocytes) per 4 mm2 of glandular tissue V. Salivary gland involvement: objective evidence of salivary gland involvement defined by a positive result for at least one of the following diagnostic tests: 1. Unstimulated whole salivary flow (\<1.5 ml in 15 minutes) 2. Parotid sialography showing the presence of diffuse sialectasias (punctate, cavitary or destructive pattern), without evidence of obstruction in the major ducts 3. Salivary scintigraphy showing delayed uptake, reduced concentration and/or delayed excretion of tracer VI. Autoantibodies: presence in the serum of the following autoantibodies: 1\. Antibodies to Ro(SSA) or La(SSB) antigens, or both * The control group should match the test group according to the age, sex and treatment region and fulfill the following: * Normal salivary flow: unstimulated \> 1.5 ml in 15 min, stimulated \> 3.5 ml in 5 min * No ocular or oral symptoms * Submission of written informed consent form Exclusion Criteria: * Persons with: 1. secundary Sjögren Syndrom (sSS) 2. severe systemic disease including severe bleeding disorder and/or conditions which put the patient at risk and/or prohibit compliance as stated by Hwang and Wang, 2006; and Hwang and Wang, 2007): 3. previous or present bisphosphonate, Denosumab or anti-angiogenetic chemotherapeutic drugs 4. poor bone quality according to Lekholm U \& Zarb GA (1985) or diagnosed osteoporosis 5. Heavy smokers, eqv. to 20+ cigarettes/day 6. Noncompliance