***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 
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    ***EXAMPLES*** 
    Input: Two hundred ears with otosclerosis have been operated upon using a 0.4-mm diameter Teflon platinum piston in 100 ears and a 0.6-mm diameter Teflon piston in the other 100 ears . The postoperative air-bone gap , calculated as the difference between the postoperative air and bone conduction levels , was smaller in the 0.6 mm group for all frequencies except at 2000 Hz , the differences were statistically insignificant except at 4000 Hz . The mean postoperative air-bone gap was 8.6 dB and 7.4 dB for the 0.4 and 0.6 mm groups , respectively , which is statistically insignificant . We found no postoperative loss of bone conduction exceeding 15 dB , there was a deterioration of more than 10 dB in three ears , one in the 0.4 mm group and two in the 0.6 mm group . According to our results , we conclude that the 0.4 mm and the 0.6 mm Teflon prostheses produce the same hearing improvement in stapes surgery for otosclerosis Tight fixation of stapes prostheses  yields better functional results because sound transmission from the incus to the prosthesis is improved . Background : The optimal prosthesis to use for otosclerosis surgery is still a matter of debate . It has been proposed that using prostheses made of Nitinol , a shape-memory metal , produces better functional results with less variability and reduced risk for middle and inner ear damage . This is thought to be because heat activation rather than manual crimping of the prosthesis loop forms a tighter fixation . Methods : Functional results of two groups were compared 1 year after surgery . In one group were 75 cases of stapedotomy performed using Nitinol prostheses .  Results were analyzed prospect ively and compared with 75 retrospectively analyzed matched controls with conventional stapes prostheses .  Crimping quality was measured in 23 patients by intraoperative laser Doppler interferometry ( LDI ) . Causality was assessed by correlating results of intraoperative LDI and postoperative pure-tone thresholds . Results : Nitinol and conventional prostheses yielded postoperative air-bone gaps ( ABGs ) of 8.0 and 11.6 dB with 71 and 43 % ABG closure within 10 dB , respectively . Intraoperatively , sound transmission was improved by 2.5 dB with the Nitinol prostheses as compared with conventional prostheses . These differences were statistically significant . Intraoperative fixation quality was positively correlated to functional outcome , but results were not statistically significant . Conclusion : Tight fixation , as provided by Nitinol prostheses leads to improved functional results because of better sound transmission properties at the incus-prosthesis interface . The improvement in ABG closure is in the range of 3 dB pure-tone average and more pronounced at higher frequencies . Nitinol prostheses provide an effective treatment option in otosclerosis surgery Objectives : This is the first clinical trial to evaluate the suitability of a new  titanium stapes prosthesis , which we developed jointly with the Kurz Company ( Dußlingen ) This study compares hearing results after stapedotomy by 0.6 mm and 0.8 mm teflon pistons . Retrospective analysis studied 100 patients r and omly selected who underwent stapedotomy for otosclerosis with insertion of 0.8 mm teflon piston prosthesis and 100 patients with 0.6 mm teflon piston prosthesis .  Air-conduction hearing level in both groups were measured before and after the procedure and the gain of the air conduction between the 2 groups at different frequencies were compared statistically . The group with the 0.8 mm prosthesis had better results that were statistically significant and more pronounced at lower frequencies The early and long-term hearing results of 1,681 primary otosclerosis operations performed by the same surgeon , Jean Marquet , were review ed retrospectively and analyzed with very strict statistical st and ards . Significantly better short- and long-term results were achieved with the stapedotomy technique compared to total stapedectomy , mainly at the higher frequencies ( 4 and 8 kHz ) important for speech discrimination . Whatever technique was used to open the footplate ( micropick , microdrill , or laser ) , no statistical audiometric difference could be found . The results were equal whether or not the stapedial tendon was preserved . Perioperative problems like pronounced oozing , difficult anatomic relationships , and accidental perilymph aspiration could affect hearing at higher frequencies . The calibrated hole technique was equally as good as conventional oval window sealing in sealing of the fenestra to prevent fistula . The stapedotomy technique was found the safest , having fewer complications This study reports the evaluation of hearing results after implantation of a Teflon piston of a different diameter in cases of otosclerosis requiring stapedotomy . By r and om selection , a Teflon piston with a shaft diameter of 0.3 mm was inserted in 34 cases and a piston with a shaft diameter of 0.4 mm in 26 cases . A retrospective analysis of the pre- and postsurgery audiological results of these two patient groups was carried out by microcomputer . A repeated statistical measures analysis of variance was used to test and estimate the air-conduction frequency-specific differences between the two prostheses with respect to changes in pre- and postoperative healing . The results of this comparative study of the two Teflon pistons with different diameters indicate statistically a greater hearing gain for the 0.4-mm prosthesis , especially in the lower frequencies Over the last 10 years , lasers have evolved to become an integral part of stapes surgery . Argon , KTP , and CO2 lasers have all been tested for their improved accuracy and safety in the middle ear . Because of the difference in optical properties between visible light ( argon , KTP ) and infrared ( CO2 ) lasers , discussion s have evolved around which laser is better and safer . In an effort to clarify the issues , a prospect i ve comparison was made of 100 consecutive primary stapedotomies by using either the CO2 or KTP laser From 1975 to 1992 , a total of 1459 primary stapedoplasty operations ( i.e. ,  stapedectomy , stapedotomy with tendon section , and stapedotomy with tendon preservation ) were performed in 1323 subjects at the Ear , Nose , and Throat Department of the University of Verona .  Pure-tone audiometry was carried out in all subjects who were operated on and who underwent 6-month and 10-year follow-ups . To evaluate the influence of stapedius tendon preservation on functional outcome , we r and omly selected subgroups of patients using the three different stapedoplasty techniques and tested them by multiple-frequency tympanometry , psychoacoustic tuning curves , and speech discrimination in noise . Finally , to assess the effect of prosthesis diameter on middle ear transfer function , we used the  electrocochleographic technique  and examined the threshold and latency of cochlear nerve compound action potentials recorded during surgery from the round window . The results of this study show that the best auditory performance in otosclerotic subjects is achieved by performing a stapedotomy of 0.7 mm diameter , using a 0.6 wire-Teflon piston , and preserving the stapedius tendon Thirty-four ears with conductive hearing loss due to otosclerosis were operated upon using the laser stapedotomy technique . Audiological results were compared with the results of 316  non-laser stapedotomies . The post-operative air-bone gap , calculated as the difference between the post-operative air and bone conduction levels , was smaller with the laser stapedotomy group . Also , the bone conduction showed significant improvement with the use of laser .  Significant sensorineural hearing loss was not found in any of the laser-treated patients . According to our results , we concluded that laser is of benefit in stapes surgery for improving the hearing results and minimizing the inner ear trauma BACKGROUND The first hearing results with a new stapes prosthesis with clip function ( Soft-CliP(R ) piston ) are presented . PATIENTS AND METHODS This new prosthesis was used in 15 patients ( mean age 45.2 years ; range 21 - 63 years ) undergoing routine stapes surgery . Soft-CliP(R ) piston prostheses with a shaft diameter of 0.4 mm and a length ranging from 4.25 mm to 5.5 mm were used . Postoperative audiological testing and measurement of the air-bone gap were performed after an average of 47.3 days and compared with the preoperative values . RESULTS The median observed postoperative air-bone gap ( ABG ) was 8.33 dB + /-4.16 dB. All patients had less than 20 dB ABG and in 53.3 % of cases was less than 10 dB. The operating time showed a clear difference between the left ( 66.5 min + /-37.79 min ) and right ears ( 47.2 min + /-11.08 min ) . DISCUSSION This new prosthesis design greatly facilitates a very difficult step in stapes surgery , the prosthesis fixation to the incus . The first postoperative hearing results are very promising but long-term results in a larger group of patients are still pending 
    Output:
    
The frequency-specific analysis of the postoperative ABG showed no advantage for the small prosthesis in the high frequencies .
There was no difference in postoperative change of bone conduction in the 0.6- and 0.4-mm groups .