***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: AIM The aim of the present study was to test in periodontal maintenance patients whether the systems for pressure control that have been commercially developed contribute to more reproducible probing depth measurements as compared with a manual probe . MATERIAL AND METHODS In 12 patients duplicate measurements were made at day 0 and 1 week later . In each patient four teeth with the deepest pockets were measured at six sites . In total 288 sites were available for comparisons . The Florida Probe ( FP ) ( 159 N/cm(2 ) ) , the Jonker Probe ( JP ) ( 153 N/cm(2 ) ) , the Brodontic probe ( BP ) ( 255 N/cm(2 ) ) and the manual probe ( MP ) were used in a r and omized scheme . RESULTS Mean probing measurements showed for the FP and the JP lower recordings than for the BP and manual probe . The FP , the BP and the MP showed no differences between the duplicate measurements , except for the JP where the second measurement was deeper . Correlation coefficients between measurements at day 0 and 1 week show for the BP and the MP are 0.90 and 0.89 , respectively , while for the FP and the JP they are 0.76 and 0.75 , respectively . CONCLUSION The BP and the MP appear to be reliable tools for reproducible pocket depth measurements in periodontal maintenance patients Over 25,000 sites around natural teeth in three stages of periodontal therapy ( prior to instrumentation , following closed subgingival instrumentation and following surgical therapy )  were independently probed by two examiners . Examiner A used a conventional periodontal probe with uncontrolled pressure . Examiner B used an identical probe tip mounted in a h and le which controlled vertical probing force at 50 g. The pressure-controlled technique produced significantly deeper clinical probing measurements on the direct facial and lingual aspects of teeth regardless of the stage of periodontal therapy that had been completed . Manual probing obtained deeper measurements on the distal-lingual aspects of teeth in the posterior regions which had not received surgical therapy . The percentage match between probing depths obtained by the two methods declined as the probing depths increased . Control of vertical force during probing may provide a more objective method of monitoring periodontal status during longitudinal trials Eighty-two periodontally involved patients were treated in a split mouth design such that one quadrant received coronal scaling ( CS ) , root planing ( RP ) , modified Widman surgery ( MW ) , and flap with osseous resection surgery ( FO ) . The therapy was performed in three phases : Phase I : the teeth previously design ated to receive RP , MW , and FO were thoroughly root planed and the teeth design ated to receive CS were scaled with no subgingival instrumentation , plaque control was initiated and reinforced for the entire mouth ; Phase II : the design ated teeth received MW or FO surgery ; and Phase III : maintenance therapy every three months . The CS teeth received coronal scaling and polishing during maintenance appointments , while RP , MW , and FO teeth received supragingival instrumentation , subgingival instrumentation and polishing .  Clinical measurements were taken initially , four weeks post-Phase I , 10 weeks post-Phase II , and after each of two years of maintenance care . All therapy modalities result ed in a decrease of mean probing depth with the FO producing the greatest decrease followed by MW , RP , and CS . The deeper the initial probing depth , the greater was the mean reduction of probing depth . FO created a loss of mean probing attachment in the 1 to 4 mm category . RP and MW produced the greatest gain of mean probing attachment in the 5 to 6 mm category . RP , MW , and FO produced similar gains in the greater than or equal to 7 mm category . FO created the most gingival recession followed by MW , RP , and CS The objective of this study was to evaluate the effect of the tine shape of 3 different periodontal probes . One tapered , one parallel-sided and one WHO-probe tine , each with a diameter of 0.5 mm at the tip , were mounted in hinged h and les exerting a constant probing force ( Brodontic ) . The h and les were adjusted to either 0.25 N ( 127 N/cm2 ) or 0.5 N ( 255 N/cm2 ) . 12 patients with moderate to severe periodontitis were measured after supra- and subgingival debridement , using all 6 possible tine/force combinations in 3 sessions . In each session one tine/force combination was used in the 1st and 3rd quadrants , and another tine/force combination in the 2nd and 4th quadrant . The measurements in the same quadrants could therefore be used for comparisons within the same site . The selection for the 2 quadrants in which a given tine/force combination was to be used , was r and omised . Calculations of differences ( mean per patient ) between probing measurements show that the WHO tine yields deeper recording than the parallel/sided and tapered tines , both at 127 N/cm2 and 255 N/cm2 . We conclude that in addition to probing force , the tine shape of a periodontal probe is of significant importance for the recorded probing depth This study was undertaken to determine the effect of gingival inflammation and probing pressure on probe tip placement in relation to the base of the gingival crevice and the most coronal connective tissue attachment fibers . Nine young male beagle dogs were divided into three groups as determined by clinical status of the gingiva following implementation of a protocol design ed to produce gingival health and disease . An electromechanical device was used to advance 0.6 mm diameter probes into the facial gingival crevices of selected teeth and to obtain force-displacement curves . The instrument stopped the probe at pressure of either 80 , 160 , 320 , 640 , 1280 , or 2560 kPa which were r and omly allocated to 12 test teeth in each dog . After the probe came to rest , it was attached to the tooth . When all 12 probes were attached , the animal was sacrificed . Blocks consisting of gingiva , probe , and tooth were processed to obtain two buccolingual sections , one containing the probe and the other immediately adjacent to it . Clinical and histometric measurements were performed and the data evaluated . Although three groups of animals were discernable by clinical criteria , only two groups , health and disease , could be formulated based on the degree of histologic inflammation . The histologic grouping was used in data analysis . Histometric distances from the cemento-enamel junction to the base of the crevice ( cJ ) , to most coronal connective tissue attachment ( cC ) and to the probe tip ( cP ) all increased with change from health to disease . However , changes in health/disease did not influence difference between distances ( cP-cJ , cP-cC ) . ( ABSTRACT TRUNCATED AT 250 WORDS Previous research has shown that probing force and probe tine shape influence the clinical ly assessed probing depth . The purpose of the present study was to investigate the effect of tine shape and probing force on probe penetration , in relation to the microscopically assessed attachment level in untreated periodontal disease . In 22 patients , scheduled for partial or full mouth tooth extraction and no history of periodontal treatment , 135 teeth were selected . At mesial and distal sites of the teeth reference marks were cut . Three probe tines , mounted in a modified Florida Probe h and piece , were tested : a tapered , a parallel and a ball-ended ; tip-diameter 0.5 mm . The three tines were distributed at r and om over the sites . At each site increasing probing forces of 0.10 N , 0.15 N , 0.20 N , 0.25 N were used . After extraction , the teeth were cleaned and stained for connective tissue fiber attachment . The distance between the reference mark and the attachment level was determined using a stereomicroscope . The results showed that the parallel and ball-ended tine measured significantly beyond the microscopically assessed attachment level at all force levels ; with increasing forces , the parallel tine measured 0.96 to 1.38 mm and the ball-ended tine 0.73 to 1.06 mm deeper . The tapered tine did not deviate significantly from the microscopic values at the forces of 0.15 , 0.20 and 0.25 N. It can be concluded that for the optimal assessment of the attachment level in inflamed periodontal conditions , a tapered probe with a tip diameter of 0.5 mm and exerting a probing force of 0.25 N may be most suitable The purpose of this study was to locate the position of the periodontal probe tip using a pressure of 126 N/cm2 ( force of 0.30N using a round periodontal probe tip with a diameter of 0.55 mm ) . The influence of gingival inflammation on this position was also studied . Subjects with three levels of periodontal health and disease were entered into the study and each contributed one experimental tooth . At each site a st and ardized probing system was used to place a probe into a clinical pocket . The probe tip was luted to the test tooth surface . The tooth with its gingival tissue and probe tip was extracted , fixed , and processed for histological measurements . Distances in mm were obtained from the cemento-enamel junction ( CEJ ) to the probe tip , to the base of the crevice/pocket , and to the most coronal connective tissue attachment . Analysis of the data indicated that clinical inflammation was not a factor in the placement of the probe tip at crevice/pocket 's l and marks relative to the CEJ ; however variability of probing may have caused the non- significance . The probing system placed the probe tip 0.66 mm apical to the base of the crevice/pocket and 0.06 mm coronal to the most coronal connective tissue attachment . These conclusions corroborated the results of the previous study in dogs which predicted probe placement of 0.44 mm apical to the base of the crevice using the st and ardized pressure of this probing system 
    Output:
    
The incremental change in PPD in healthy/treated sites decreased as the pressure increased above 398 N/cm(2 ) .
In diseased sites , this phenomenon was already present at pressures above 100 N/cm(2 ) .
The results show that with increasing probing pressure , the PPD increases .
The dimensions of the increase are dependent on the periodontal tissue conditions