non-HA Group Research Articles

Alveolar ridge augmentation using titanium micromesh: An experimental study in dogs

Purpose: Augmentation of the alveolar ridge before implant placement is frequently performed. The purpose of this study was to compare the amount and quality of bone formation under Micro Titanium Augmentation Mesh (M-TAM) when used alone for guided tissue regeneration or in combination with a porous hydroxyapatite (HA) bone graft substitute. Materials and Methods: Nine adult female dogs underwent extraction of premolars and molars and had a knife-edge ridge created. Three months later, the ridges were augmented with either M-TAM alone or M-TAM with a nonresorbable porous HA (Interpore 200; Interpore Cross International, Irvine, CA). Six months after augmentation, the dogs were killed, and the mandibles were harvested and imaged using 3-dimensional computed axial tomography. Statistical analysis was performed from the data obtained from the scans. The mandibles were then fixed, sectioned, and examined by light microscopy. Results: Dehiscence occurred in 22 of 32 experimental sites. Seven of these 22 dehisced sites showed increased ridge width. Ridge width increased in both the HA and non-HA groups. The HA group showed a greater increase in ridge width. Conclusion: A high rate of dehiscence was observed in this animal study using M-TAM for guided tissue regeneration. In animals that did not dehisce, increased width was greater when nonresorbable porous HA was used as a bone graft substitute. © 2003 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 61:347-353, 2003

Hydroxyapatite: Catalyst or conjuror?

A prospective, randomized, intermediate-term study of 174 patients (199 hips) comparing proximally hydroxyapatite (HA)-coated and non-HA-coated surfaces of identical stem design is presented. Clinical and radiographic data from 152 patients (174 hips) confirmed comparable outcomes in both groups according to the Hospital for Special Surgery modification of the Postel–d'Aubigne Hip Rating System. The non-HA group showed significantly higher (P=.03) activity-related thigh pain, however. There were no significant radiographic differences, with all stems showing bone ongrowth. The use of HA-coated stems resulted in early recovery of function and reduced activity-related trochanteric and thigh pain. A possible explanation for the difference is most likely early superior osseointegration. HA as a biologic adjuvant should gain widespread acceptance because of rapid recovery of function and lesser trochanteric and thigh pain. Copyright 2002, Elsevier Science (USA). All rights reserved.

セメントレスＴＨＡの中期成績

The results of fifty-five cementless total hip arthroplasties using the Omniflex system were reviewed. All patients were followed clinically and radiographically for more than four years.The AD stem (non-HA stem) was used from January 1993 to October 1995, and the Securflex (HA stem) was used from November 1995 to December 1996.On the stem side, five unstable fixation stems were observed in the non-HA group. In the HA group, we found early osseointegration in all cases. On the socket side, there were no loose shells.We need to observe osteolysis carefully since the onset of osteolysis seems to increase gradually with polyethylene wear.

Analysis of 200 university hospital hearing aid clinic patients

We statistically studied patients who visited our hearing aid clinic to determine what segment of the population may benefit from hearing aids. Subjects were 200 patients from 5 to 89 years of age who had visited the Hearing Aid Clinic of Otorhinolaryngology, Nagoya University Hospital, between January 1998 and March 2000. This clinic lent out hearing aids. Subjects were divided into 2 groups those having their own hearing aids either new or earlier (HA group) and those giving up hearing aids after a trial (non-HA group). Mean better hearing levels in pure tone average were 50.6 dB in the HA group and 44.5 dB in the non-HA group. Mean better maximum speech recognition scores were 81.5% in the HA group and 85.3% in the non-HA group. The distribution of better hearing has shown that patients with mild hearing loss (better pure tone average < 40 dB) account for more than a quarter of all hearing aid clinic patients. Among patients with mild hearing loss, 60% had their own hearing aids. The need for rehabilitation in the mild hearing loss population thus appears large. Their intent to wear hearing aids influenced whether patients agreed or declined hearing aids after a trial. The period from use until patients made a decision was 2 weeks in 65% of those declining use and 35% of those agreeing to use. Over 15% of those agreeing called for a trial period longer than 8 weeks. Hearing aid trials provide useful information for both patients and surgeons before choosing surgery for a difficult ear condition. In this research, 18 patients needed counseling about both amplification and surgery. Bridging between ear surgery and hearing aid wearing is a vital role of hearing aid clinics at university hospitals.

高位けい骨骨切り術後患者に対するヒアルロン酸ナトリウムの効果

We studied the clinical effects of sodium hyaluronate (HA) on patients treated with high tibial osteotomy (HTO). Nine knees from 9 patients with osteoarthritis (OA) were selected randomly as a case group, and were injected with HA into the affected knee inter-articularly once a week for five weeks after HTO (HA group). Nine knees from 9 patients with OA of the knee without HA injection were selected as a control group (non-HA group). Controls were matched to cases for age, body weight, range of motion (ROM) and JOA score before HTO. ROM at five weeks and one year after HTO, and JOA score at one year after HTO were compared between the two groups. ROM at five weeks for HA group and non-HA group (118° and 93°, respectively) reached statistical significance (P<0.03). ROM at one year for HA group and non-HA group were 134° and 132°, respectively without statistical significance. JOA score at one year for HA group and non-HA group were 82 and 86, respectively without statistical significance. Intra-articular injection of HA after HTO is effective on the early achievement of full ROM.