Biomedical subjects

Gerald Krennmair

Publications and source records attributed to Gerald Krennmair.

11 recordsLinked to original sources

PubMed2004

[Infection sources in HNO- and jawbone regions in patients before valve replacement surgery].

BACKGROUND: Prosthetic valve endocarditis is a life-threatening complication after valve replacement surgery. Therefore, it is common to perform a screening for potential sources of infection before surgery in order to be able to do a prophylactic treatment. PATIENTS AND METHOD: The incidence of potential infectious sources of bacteremia in the dental, jaw and nasopharyngeal area was evaluated in 92 patients going to have valve replacement surgery. Screening examinations were an X-ray of the paranasal sinuses and a panoramic radiograph of the dental arch. Chronic apical periodontitis, cysts and remaining radices were counted as dental sources. Each shadow in the paranasal sinuses X-ray was seen as pathological and was further investigated by an otorhinolaryngologist. RESULTS: A potential infectious source was found in 49 patients. 42 patients had a dental infectious source with need for treatment. 19 patients showed a pathologic sinus X-ray (three aspergillomas, three sinusitis, the others had a chronic polyposis with no need for treatment). Twelve patients had dental as well as sinusoidal sources. Erythrocyte sedimentation rate did not refer to the appearance of infectious sources. Patients going to have a mitral valve replacement had most dental sources (61%), 47% of the patients with planned aortic valve replacement, 50% of the patients planned to get more than one heart valve replaced, 50% of the patients getting mitral valve replacement and CABG and 40% of the patients waiting for aortic valve replacement and CABG had dental foci. CONCLUSION: Screening for infectious foci before valve replacement surgery diagnosed foci in a high percentage of the patients. Nevertheless current data concerning whether a prophylactic treatment may reduce the incidence of prosthetic valve endocarditis are conflicting.

Adult↗

PubMed2004

[On the involvement of the temporomandibular joint in rheumatoid arthritis].

64 patients with rheumatoid arthritis (RA) were examined for temporomandibular joint (TMJ) symptoms as well as for the severity and incidence of their symptoms. In detailed interviews, a total of 34 patients (53.1%) reported TMJ symptoms, the main complaints being problems during opening and closing of the mouth (45.2%). RA patients with TMJ symptoms differed significantly from those without TMJ symptoms (p < 0.01) in the duration (121.7 +/- 100.5 months vs. 37.1 +/- 27.6 months) and the state of activity of the basic disease. The patients subjectively evaluated the severity of the TMJ symptoms as mild to moderate (grade: 2-3; severity: 241 +/- 1.01). Almost 70% reported occasional symptoms, 22.5% frequent symptoms and 10.6% permanent symptoms (p < 0.01). 61.8% (21/34) of the patients showed no radiographic change in the shape of the TMJ condyle, whereas 11.8% (4/34) demonstrated a change on one side an 26.4% (9/34) a change on both sides. There was no difference in the severity of the TMJ symptoms between patients with an unchanged condyle (n = 21; severity: 2.33 +/- 0.96) and patients with changes in condylar shape (n = 13; severity: 2.5 +/- 1.12). A frequent involvement of the temporomandibular joint in RA can be considered certain. The symptoms, which were generally moderate, can cause a marked impairment of daily used functions, such as chewing and speaking.

Adult↗

PubMed2003

Variants of ossification in the stylohyoid chain.

The purpose of this study was to evaluate the age-related differences in the incidence, length and topographic location of ossification in the stylohyoid chain. Panoramic radiographs of 420 patients (795 reviewed stylohyoid-chains), subdivided into 4 age groups (20 years and under, 21 to 40 years, 41 to 60 years, older than 60 years) were reviewed and examined for the incidence, length and topographic location of stylohyoidal ossification. 245 (30.8%) out of 795 reviewed stylohyoidal chains showed radiological variabilities (elongation of the styloid process and/or ossification of the stylohyoid ligament). With increasing age, there was an increase in the incidence and length of stylohyoidal ossifications (p<0.01). A significant linear correlation between the length of the stylohyoidal ossifications and age was only found in the young age group (under 20 yrs.; p<0.01). In the young age group (under 20 yrs), there was also a higher prevalence of isolated locations in the superior stylohyoidal segment. With increasing age, there was a pronounced presence of ossifications in the middle and inferior stylohyoid segments and combinations of ossified variabilities. Stylohyoidal ossifications show age-related differences in incidence, length and topographical location. Stylohyoid ossifications gain a different importance in adult patients than in juvenile patients.

Adolescent↗

PubMedDate not supplied

Single-tooth replacement with the Frialit-2 system: a retrospective clinical analysis of 146 implants.

PURPOSE: This study was intended to provide a report of experience and results with Frialit-2 implants used for single-tooth replacement. MATERIALS AND METHODS: Over a 7-year period (1994-2000), 146 single-tooth implants (84 maxilla, 62 mandible) were placed in 112 patients (67 females, 45 males; 31.2 +/- 16.4 years). The sites included maxillary anterior teeth (n = 38) as well as the mandibular premolars and molars (n = 57). Ninety-three crowns were cemented and 53 crowns were screw mounted (22 with vertical, 31 with horizontal screws) on standard abutments. The follow-up time varied between 3 and 80 months (35.8 +/- 16.5 months). RESULTS: Two implants (1.4%) were lost, 1 during early loading and the other after 6 years. The most frequent prosthetic complication was isolated crown loosening of cemented crowns requiring recementation of 9 crowns (9.9%). Crowns with vertical screws showed no crown and/or screw loosening. Four crowns (2.8%) were replaced because of ceramic fracture. DISCUSSION: Peri-implant soft tissue condition, bone resorption, and Periotest values indicated satisfactory results. The cumulative implant survival rate during the follow-up period was 97.3%, and that of the crowns 96.4% (total cumulative survival rate 93.7%). CONCLUSIONS: With the low number of abutment screw loosenings (3.5%), the deep internal hexagonal retention compared favorably to external retention methods. The predominant use of long implants (98.4% > or = 13 mm) allowed a favorable implant/crown ratio with the potential for problem-free, long-term results.

Adult↗

PubMedDate not supplied

Provisional implants for anchoring removable interim prostheses in edentulous jaws: a clinical study.

PURPOSE: The behavior of provisional implants in edentulous maxillae/mandibles used for anchoring removable interim overdentures was followed for the time of the intended healing of the definitive implants. MATERIALS AND METHODS: Twenty-eight edentulous arches (19 maxillae, 9 mandibles) were provided with 77 provisional implants (2 to 4 in maxillae; 2 or 3 in mandibles) for anchoring removable interim prostheses (overdentures). The provisional implants were to be maintained until final restoration (6 to 9 months in the maxilla and 3 months in the mandible). The loss rate of provisional implants and handling and behavior of the anchored overdenture were monitored until the definitive prosthetic restoration was placed. RESULTS: Twenty-three (29.8%) of the 77 provisional implants were lost prematurely. The loss rate of maxillary provisional implants (21/58; 36.2%) was significantly higher than that of mandibular implants (2/19; 10.5%) (P < .01). Determination of terminal stability (by means of the Periotest) of the provisional implants showed higher stability in the mandible (+3.8 +/- 2.3) than in the maxilla (+8.6 +/- 3.9) (P < .05). In obvious contrast to mandibular interim overdentures, handling of maxillary interim overdentures was found to improve significantly during the follow-up period (P < .01). DISCUSSION AND CONCLUSION: With both the low loss rate in the mandible and the higher loss rate seen in the maxilla, placement of provisional implants fulfills the requirements for initiating immediate prosthetic rehabilitation. The removable interim overdenture can be adequately stabilized and provides for added patient comfort and satisfaction as compared to a conventional complete denture. An important aspect of the continued use of provisional implants concerns the expectations placed in these implants by both clinician and patient, which are quite different than those for definitive implants.

Chi-Square Distribution↗

PubMedDate not supplied

Status of teeth adjacent to single-tooth implants.

PURPOSE: This study evaluated the status of teeth adjacent to single-tooth implants in the anterior and posterior jaw during a follow-up of more than 3 years. MATERIALS AND METHODS: Seventy-eight single-tooth implants and 148 adjacent teeth were followed for a mean of 58 months. Implant survival rate, peri-implant structures, and prosthetic complication rates were evaluated. Crowns and periodontal status of adjacent teeth were compared at crown placement and at the last examination. Horizontal distance from the implant edge to adjacent teeth was calculated and compared for anterior and posterior regions. The influence of approximal crestal bone resorption of the adjacent teeth was calculated using multivariate regression analysis. RESULTS: The clinical findings for implants (one loss), peri-implant structures, and prosthetic complication rates (three crown fractures) were excellent. There was a high proportion of intact adjacent teeth in both anterior and posterior regions at crown placement and at the follow-up examination. No adjacent teeth required extraction or endodontic treatment, and only four required restoration. Comparison of the periodontal status at crown placement and at follow-up revealed no differences for plaque and bleeding indices or for pocket depth of adjacent teeth. There was a significant influence of the horizontal distance on approximal bone loss in the closer distance of the anterior region, but not in the posterior region. CONCLUSION: The crown and periodontal status of teeth adjacent to single-implant restorations was excellent. The approximal bone crest reduction of the adjacent teeth was significantly influenced by the horizontal distance between the implant edge and neighboring tooth.

Adult↗

PubMedDate not supplied

Clinical analysis of wide-diameter frialit-2 implants.

PURPOSE: To evaluate wide-diameter (ie, 5.5-mm-wide) Frialit-2 implants used for several forms of prosthetic rehabilitation. MATERIALS AND METHODS: In this retrospective study, 121 wide implants (74 maxillary, 47 mandibular) were placed in 114 patients (61 female, 53 male, mean age 37.2 +/- 14.9 years). Thirty-six single-tooth restorations, 63 fixed partial dentures (68 implants), 6 removable overdentures (7 implants), and 3 fixed complete dentures (8 implants) were placed. Eighty-seven were placed in the molar regions. The follow-up period for the implants was 12 to 114 months (mean 41.8 +/- 18.5 months). Peri-implant bone loss, pocket depth, Plaque Index values, Bleeding Index values, and Periotest values were evaluated. RESULTS: Overall, 2 maxillary implants were lost, for a cumulative survival rate of 98.3% (97.3% in the maxilla; 100% in the mandible). Mean peri-implant pocket depth (3.4 +/- 1.1 mm), bone resorption (1.4 +/- 1.2 mm), Periotest values (-4.3 +/- 3.1) as well as the Plaque Index and Bleeding Index (grades of 0 in 80% of cases) indicated acceptable results. DISCUSSION: The high survival rate may be attributed to avoidance of the use of short wide-diameter implants, and the primary intention to place wide-diameter implants. Preference of the molar region was a consequence of the peri-implant bone situation in the premolar region, which was frequently inadequate for a 5.5-mm implant. CONCLUSIONS: The use of wide-diameter implants can be a viable treatment option and may provide benefits in posterior regions for long-term maintenance of various implant-supported prosthetic rehabilitations. Some anatomic and prosthodontic limitations for the use of wide implants were

Adult↗

PubMedDate not supplied

Maxillary interim overdentures retained by splinted or unsplinted provisional implants.

PURPOSE: The survival rate of splinted and unsplinted provisional implants for anchoring removable interim overdentures, as well as handling and maintenance of the interim dentures, was evaluated. MATERIALS AND METHODS: Eighteen edentulous maxillae were provided with 72 provisional implants for anchoring interim overdentures. For 10 patients, 40 unsplinted implants were used with conical copings to retain the provisional prostheses, while for 8 patients 32 implants had a splinted bar architecture for supporting the interim prostheses. Failure rate of provisional implants, as well as handling and behavior of the anchored interim overdentures, was followed until definitive prosthetic restoration and compared between groups. RESULTS: Eighteen (25.0%) of the 72 provisional implants were prematurely lost. The loss rate of unsplinted implants (37.5%) was significantly higher than that of splinted implants (9.3%). Patient handling and maintenance of maxillary interim overdentures during the follow-up period was found to be easier with the splinted bar-retained method than with the unsplinted prosthodontic method. CONCLUSION: Placement of provisional implants fulfilled the requirements for initiating immediate prosthetic rehabilitation and showed that removable interim overdentures can be adequately stabilized and provide added patient comfort and satisfaction. The results suggest benefits of the splinted retention modality over the unsplinted method because of advantages regarding failure rate, patient handling, and interim denture maintenance.

Aged↗

PubMedDate not supplied

Clinical outcome and prosthodontic compensation of tilted interforaminal implants for mandibular overdentures.

PURPOSE: The aim of this study was to evaluate the sagittal inclination of interforaminal implants, the clinical implant outcome, and the necessary extent of prosthodontic compensation modalities for implant overdentures (IODs). MATERIALS AND METHODS: Lateral cephalometric radiographs of 62 patients, each with a mandibular IOD retained by 2 to 4 implants, were analyzed. The sagittal inclination of the longitudinal implant axis of the most anterior implant was analyzed relative to the mandibular and occlusal planes. The angle needed to compensate for the inclination of the mandibular implant to obtain Angle's class I for the prosthesis (the compensation angle) was measured and compared with respect to skeletal class. Peri-implant structures were measured using the Plaque Index and the Gingival Index. The compensation angle was correlated with the mandibular implant inclination, the degree of mandibular atrophy, and the anterior facial height. RESULTS: The most anterior mandibular implants showed a mean retroinclination of 74.3 +/- 9.3 degrees in relation to the mandibular plane; retroinclination was significantly more pronounced in skeletal class II than skeletal classes I and III (P < .05). The compensation angle (26.9 +/- 10.5 degrees) was more significant for skeletal class II than for skeletal classes I and III (P < .01). Sagittal mandibular implant inclination correlated significantly to the compensation angle (r = -0.46; P < .05), mandibular atrophy (r = 0.32; P < .05) and mandibular facial height (r = -0.45; P < .05). Implant survival rate and peri-implant parameters (bone loss, pocket-depth, Plaque and Gingival Indices) of the interforaminal implants were not shown to be influenced by implant retroinclination. Nine patients (2 skeletal class 1, 7 skeletal class II) reported phonetic problems with the IOD because of narrowing of the lingual space but described significant improvement after a median 4.7 months (range, 3 to 12 months). DISCUSSION AND CONCLUSION: Depending on skeletal class, prosthetic compensatory mechanisms will be operative in the presence of mandibular implant retroinclination for IOD. Knowledge of mandibular inclinations and the compensatory mechanisms may be an essential factor in successful prosthetic rehabilitation and may provide for a homogenous design of the bar construction and easier handling and may also reduce stress on the attachment mechanism.

Cephalometry↗

PubMedDate not supplied

Implant-supported mandibular overdentures retained with ball or telescopic crown attachments: a 3-year prospective study.

PURPOSE: The aim of the present study was to evaluate implant survival, peri-implant conditions, and prosthodontic maintenance requirements for implant-supported mandibular overdentures in atrophic mandibles retained with ball or resilient telescopic crown attachments during a 3-year period. MATERIALS AND METHODS: Twenty-five patients with edentulous mandibles each received 2 Camlog root-form dental implants in the mandibular interforaminal (canine) region. The denture attachment system was chosen randomly; 13 patients received ball attachments and 12 patients received resilient telescopic crowns. Implant survival, implant mobility (Periotest values), and peri-implant conditions such as bone resorption, pocket depth, Plaque Index, Gingiva Index, Bleeding Index, and Calculus Index values were assessed for each implant. In addition, detailed prosthodontic maintenance was evaluated during the follow-up period and the 2 retention modalities were compared. RESULTS: There were no differences in implant survival, implant mobility (Periotest values), and peri-implant conditions between the 2 retention modalities. During the 3-year period significantly more complications/interventions for maintenance purposes were registered in the ball group (62 interventions) than in the telescopic crown group (26 interventions; P < .01). CONCLUSION: The results indicate that both ball attachments and resilient telescopic crowns used on isolated implants in the edentulous mandible are viable treatment options. Implant success and peri-implant conditions did not differ between ball attachments and telescopic crowns used as retention modalities for implant overdentures, but the frequency of technical complications was significantly higher with ball attachments than with resilient telescopic crowns.

Crowns↗

PubMedDate not supplied

Computerized tomography-assisted calculation of sinus augmentation volume.

PURPOSE: This study was intended to calculate the augmentation volume for a sinus lift procedure based on cross-sectional computerized tomography (CT) scans for 2 different augmentation heights. MATERIALS AND METHODS: Based on area calculations of cross-sectional CT scans, the volume of additional bone needed was calculated for 44 sinus lift procedures. The amount of bone volume needed to raise the sinus floor to heights of both 12 and 17 mm was calculated. RESULTS: To achieve a sinus floor height of 12 mm, it was necessary to increase the height by a mean of 7.2+/-2.1 mm (range, 3.0 to 10.5 mm), depending on the residual ridge height; to achieve a height of 17 mm, a mean of 12.4+/-2.0 mm (range, 8.5 to 15.5 mm) was required (P < .01). The calculated augmentation volume for an augmentation height of 12 mm was 1.7+/-.9 cm3; for an augmentation height of 17 mm, the volume required was 3.6+/-1.5 cm3. Increasing the height of the sinus lift by 5 mm, ie, from 12 mm to 17 mm augmentation height, increased the augmentation volume by 100%. A significant correlation was found between augmentation height and the calculated sinus lift augmentation volume (r = 0. 78, P < .01). DISCUSSION AND CONCLUSION: Detailed preoperative knowledge of sinus lift augmentation volume is helpful as a predictive value in deciding on a donor site for harvesting autogenous bone and on the ratio of bone to bone substitute to use. Calculation of the augmentation size can help determine the surgical approach and thus perioperative treatment and the costs of the surgery for both patients and clinicians.

Adult↗