Levels of glycosaminoglycans in peri-implant sulcus fluid as a means of monitoring bone response to endosseous dental implants

The presence of certain glycosaminoglycans in peri-implant sulcus fluid may be an effective means of monitoring changes in bone metabolic activity following initial loading of implant abutments. This study has investigated levels of chondroitin 4 sulphate and hyaluronan in peri-implant sulcus fluid from titanium osseointegrated implants following initial abutment placement and exposure to masticatory stresses. Abutments were placed after a 3-month osseointegration period post-initial surgical placement of the interosseous stage. 10 edentulous patients, each with 5 mandibular implants were reviewed at 2, 4, 6 and 8 days after abutment placement. Clinical details were assessed and recorded and sulcus fluid collected in microcapillary tubes for a 5-min period for each abutment. Levels of glycosaminoglycans were assessed using cellulose acetate electrophoresis and densitometric scanning of alcian blue stained strips against known glycosaminoglycan standards. Maximum levels of sulcus fluid (0.3 mu l/5 min) were evident at 4 days with a decreased towards 8days. Hyaluronan was detected within a similar range of values reaching maximal levels at 4 days and decreasing by 8 days. Levels of sulphated glycosaminoglycans were also maximal at 2-4 days (range 0.03 - 0.126 mu g/5 min) and decreased at 6-8 days. Hyaluronan was detected within a similar range of values reaching maximal levels at 4 days and decreasing by 8 days. The results indicate that glycosaminoglycan levels of peri-implant sulcus fluid is an effective means of measuring and maintaining changes in bone metabolism. The absence of proteodermatan sulphate precludes soft tissues being a source of these markers.