Gerald Krennmair

Maxillary sinus septa: incidence, morphology and clinical implications

This study was carried out to examine the incidence, morphology and clinical implication of antral septa. Out of 265 maxillary sinuses, 65 sinuses in atrophic maxillae were examined clinically during sinus floor elevation and 200 sinuses examined radiographically (CT), the latter being further subdivided into non-atrophic/dentate and atrophic/edentulous maxillary segments. Eighteen (27.7%) out of 65 clinically-examined maxillae and 32 (16%) out of the 200 non-preselected CT-examined maxillary sinuses showed antral septa. CT-topogram subclassification revealed 21 septa (13.2%) in 159 non-atrophic and 11 septa (26.8%) in 41 atrophic maxillary segments (P < 0.01). Morphologically, CT examination yielded one complete septum (0.5%), 21 incomplete septa on the sinus floor and 10 incomplete septa on the anterior antral wall (5%). CT revealed a significantly greater dimension of antral septa in non-atrophic maxillary segments than in atrophic ones (P < 0.01). In atrophic maxillary sinuses, the incidence (27.7% vs 26.8%), morphology (all septa located on sinus floor) and height (8.1 +/- 2.5 mm vs 6.8 +/- 1.6 mm) did not differ between the clinical and the CT examinations. Detailed knowledge about location, morphology and height of antral septa is clinically relevant to reduce the rate of complications when maxillary sinus surgery, i.e. sinus floor elevation, is carried out.

The incidence, location, and height of maxillary sinus septa in the edentulous and dentate maxilla

PURPOSE This study evaluated the incidence, location, and height of antral septa and demonstrates their clinical implications. MATERIALS AND METHODS One hundred ninety-four maxillary posterior regions, subdivided into four groups (group 1, 61 clinically examined atrophic ridges; group 2, 41 anatomically examined atrophic ridges; group 3, 42 radiographically [CT] examined atrophic ridges; and group 4, 50 CT examined dentate maxillary ridges), were examined for the incidence, location, and height of antral septa. RESULTS The incidence of antral septa was significantly greater (P<.01) in atrophic edentulous regions (groups 1, 2, and 3) than in dentate regions (group 4). However, the septa were much lower (P<.01). In atrophic maxillae, about 70% of antral septa were located in the anterior (premolar) region. CONCLUSIONS Antral septa are more commonly found in edentulous atrophic maxillae than in dentate maxillae. The septae in edentulous atrophic maxillae are shorter than those found in dentate maxillae. When present, maxillary sinus septae are more common anteriorly than posteriorly. CT scanning is the preferred radiographic method for detecting the presence (or absence) of sinus septae. Panoramic radiography has less sensitivity and specificity than CT scanning for the detection of sinus septa.

Gingivomorphometry - esthetic evaluation of the crown-mucogingival complex: a new method for collection and measurement of standardized and reproducible data in oral photography

OBJECTIVES A new method is introduced for the esthetic evaluation of the periimplant mucogingival complex through collection of standardized oral photographs and computer-assisted measurement of reproducible data. Using this method, different soft tissue and crown parameters in the dentogingival complex can be measured and the esthetic outcome monitored. MATERIAL AND METHODS A photographic device for standardized oral photography and a standard protocol for the esthetic evaluation of the crown-mucogingival complex is presented, comprising six soft tissue parameters: (1) mesial and (2) distal papilla areas, (3) mesial and (4) distal papilla heights, (5) soft tissue-crown perimeter, and (6) gingival recession. In order to demonstrate the reproducibility of standardized oral photographs and the accuracy of the measurement of the six parameters, the data obtained in each of two such standardized clinical photographs, taken at 10-14 days intervals, of the anterior maxillary region from 10 patients with no apparent dental disease were compared. For the statistical analysis of the reproducibility of these dependent data the 95% confidence interval and the coefficients of variation were calculated from measurement means and ranges of each of the above parameters, pooled from all 10 patients. RESULTS Statistical analysis revealed high reproducibility with no significant differences between the range of mean values of all six parameter measurements on the first and second standardized oral photograph of the same patient, respectively. CONCLUSION Gingivomorphometry on standardized oral photographs can be considered to be an accurate and reproducible method for the evaluation and measurement of different dentogingival and periimplant parameters.

Clinical outcome and peri-implant findings of four-implant-supported distal cantilevered fixed mandibular prostheses: five-year results.

PURPOSE This retrospective study evaluated implant and prosthodontic survival/success rates of four-implant-supported distal cantilevered mandibular fixed prostheses over more than 5 years of clinical use. MATERIALS AND METHODS Patients with mandibular edentulism treated with four-implant mandibular prostheses with distal extensions were evaluated. Cumulative implant survival/success rates, peri-implant conditions, and prosthodontic maintenance efforts were assessed. Relationships between the degree of distal implant tilting, length of cantilevers, and implant-generated supporting zone were evaluated. RESULTS Thirty-eight patients with 152 implants (90.5% of the original sample) were available for follow-up after 5 to 7 years (mean follow-up, 66.5 ± 3.1 months). The cumulative survival and success rates for included implants were 100% and 98.6%, respectively. Denture cantilever length (mean, 14.7 ± 2.3 mm; range, 9 to 20 mm) and implant-generated supporting zone (mean, 318.9 ± 48.1 mm(2); range, 225 to 410 mm(2)) showed significant positive and negative correlations, respectively, with the inclination of tilted distal implants toward the occlusal plane (76 ± 7.2 degrees; range, 65 to 90 degrees). Peri-implant marginal bone resorption (1.5 ± 0.4 mm) and pocket depths (1.8 ± 0.8 mm) were similar for anterior and posterior implants and were not influenced by degree of tilting or cantilever length. Plaque and calculus conditions were poorer for anterior implants than for posterior implants. No dentures fractured; however, fractures of resin tooth veneer material, denture rebasing, and a strong need for cleaning as a result of resin discoloration were seen. CONCLUSION Fixed four-implant rehabilitations with distal cantilevers of a defined length with or without distally tilted implants showed high success rates. Inferior hygiene in the anterior mandible regions may be a result of reduced cleansability and variations in anatomical landmarks. Resin veneering proved advantageous for repair or modification but disadvantageous for discoloration.

Variants of ossification in the stylohyoid chain.

ABSTRACT 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 20yrs), 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.

The incidence and influence of abnormal styloid conditions on the etiology of craniomandibular functional disorders.

This study aimed to examine the incidence and influence of craniomandibular functional disorders caused by abnormal styloid-stylohyoid chains. Seven hundred sixty-five patients with temporomandibular joint (TMJ) disorders were divided into two groups (with and without radiographically visible abnormal styloid conditions). In the group with abnormal stylohyoid conditions, the etiology of TMJ disorders was further subdivided into poly-, oligo- and monoetiological factors, and, after this classification, evaluated regarding a clear, possible or unlikely involvement of abnormal stylohyoid conditions in TMJ disorders. One hundred thirty-six out of 765 patients presented abnormal styloid-stylohyoid chains. One hundred five of the patients (77.2%) demonstrated polyetiological causes of TMJ symptoms with an unlikely involvement of the abnormal styloid-stylohyoid chain. Twenty-nine of the patients (21.3%) showed oligoetiological causes with possible involvement of the abnormal styloid-stylohyoid chain. In two patients (1.5%), the abnormal styloid conditions showed up as the only definite cause of TMJ symptoms (monoetiological). Detailed knowledge of variations and possible effects of suprahyoid structures is important for an accurate diagnosis of TMJ disorders. All in all, the incidence of a stylohyoid involvement in TMJ disorders is very low. However, after an initial subdivision into abnormal and normal stylohyoid conditions, the incidence of pathological stylohyoid chains gains significant importance in the etiology of TMJ disorders.

Planning Implants Crown Down—A Systematic Quality Control for Proof of Concept

PURPOSE We evaluated an innovative approach for conventional surgical or transmucosal implantation applying backward planning with bone oriented crown down implant positions, followed by immediate restoration. MATERIALS AND METHODS Our workflow combined computer-assisted preoperative planning with the well-known intraoperative handling of surgical templates. To guarantee optimal accuracy, the complete process was bone borne, not soft tissue borne. Furthermore, in this concept, the definite prosthesis was manufactured on a plaster cast and fixed with technical implants inserted into the model using the same drilling template applied for intraoperative guidance of the drill. This bone-based workflow avoids the accumulation of errors throughout all steps of the treatment. In the present study, we have provided a concise quantitative quality control using 4 in vivo implants. This goal was accomplished by image matching of the preoperative plan with the corresponding postoperative computed tomography scan, applying descriptive statistics, the 1-sample t test, and the Student t test. RESULTS Statistical evaluation showed that the bone-borne drilling template provides sufficient accuracy for immediate restoration with the definite prosthesis at the end of the operation. Deviation in the apex plane was 0.8 ± 0.42 mm, with 0.33 at the maximum. The angular deviation was 3.18° ± 0.78°. CONCLUSIONS Our workflow is a promising approach with respect to handling, accuracy, and intraoperative safety.

Periodontal and coronary heart disease in patients undergoing coronary angiography

Periodontal inflammation has been implicated in atherosclerosis and coronary heart disease (CHD). Coronary angiography (CA) is used in the assessment of CHD; only a few studies have evaluated periodontal disease (PD) and angiographic measures of coronary atherosclerosis. The aim of this study was to investigate the association between CHD and PD. In this prospective epidemiologic study, 466 patients underwent CA and were assessed for PD. All patients underwent physical, laboratory, cardiac, and dental examination including dental x-rays. Periodontal disease and coronary angiograms were evaluated blindly by a dentist and 2 cardiologists, respectively. A coronary stenosis greater than 50% was ruled as CHD. Periodontal disease was defined and measured with the Community Periodontal Index of Treatment Needs (CPITN); and if at least 2 sextants (segments dividing mandible and maxilla into 6) were recorded as having CPITN of at least 3 (signifying that sextant had periodontal pocket depth ≥ 3.5 mm), the patient was coded as having PD. Three-hundred forty-nine patients (74.9%) had CHD assessed by CA The CHD patients had PD in 55.6% vs 41.9% in the non-CHD patients (P < .01). The CPITN scores were significantly higher in patients with vs without CHD, 2.43 vs 2.16, respectively (P = .023). After adjusting for age, sex, and risk factors for atherosclerosis with additional inclusion of C-reactive protein and erythrocyte sedimentation rate, PD remained significantly related to CHD (odds ratio = 1.9; 95% confidence interval, 1.2-3.1). Other predictors for CHD were male sex, age, high-density lipoprotein cholesterol, and diabetes. Our results demonstrate an increased odds ratio for angiographically determined CHD in patients with PD and that CHD and PD may cluster in particular groups of a population. Our data indicate that PD represents a potentially modifiable risk factor that is both preventable and treatable with predictable treatments that pose negligible risk.

Mandibular Full‐Arch Fixed Prostheses Supported on 4 Implants with Either Axial Or Tilted Distal Implants: A 3‐Year Prospective Study

PURPOSE This prospective study evaluated the clinical and radiographic outcome of distally cantilevered 4-implant-supported fixed mandibular prostheses (4-ISFMP) with distal implants either in axial or distally tilted direction. MATERIAL AND METHODS Forty-one mandibulary edentulous patients received acrylic veneered 4-ISFMP with casted framework. Based on distal implant placement direction patients were assigned to 2 groups: 21 patients with four (2 anterior/2 posterior) axial implants (axial-group I) and 20 patients with 2 anterior axial/2 distal tilted implants (tilted-group II). Patients were prospectively followed for 3 years by annual examinations of implants and prosthetic survival rates including assessment for biological and mechanical complications. Additionally, peri-implant marginal bone resorption [MBR], pocket depth [PD], plaque index [PI], bleeding index [BI] and gingival index [GI], and calculus index [CI] were evaluated at each annual follow-up. RESULTS 37/41 patients (19 axial-group I, 18 tilted-group II) and 148/164 implants were followed at the 1-, 2-, and 3-year evaluation (dropout rate: 11.8%) presenting no implant and denture loss (100% survival). The overall, MBR at year 1, 2, and 3 was 1.11 ± 0.4 mm, 1.26 ± 0.42 mm, and 1.40 ± 0.41 mm, respectively, representing a significant (p < .001) continuing time depending annual reduction. MBR and PD did not differ between anterior and posterior regions in both groups or for anterior and posterior regions between the groups. PI and CI were significantly (p < .001) higher for implants in anterior regions than for posterior regions in both groups. Moreover, posterior implant regions showed significantly (p < .001) higher PI and CI for axial-group I than for tilted-group II over time. Biological and mechanical complications as well as GI and BI did not differ between the groups over a 3-year follow-up period. CONCLUSION For clinical implant and prosthesis outcome no statistical significant mean differences were noted for distally cantilevered 4-ISFMP supported by distal implants placed in tilted or axial direction.

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

Hintergrund:Die Endokarditis künstlicher Herzklappen ist ein gefürchtetes Krankheitsbild. Daher wird zumeist routinemäßig vor einer Klappenoperation eine Fokussuche auch beim asymptomatischen Patienten durchgeführt, um potentielle infektiöse Streuherde aufzufinden und noch vor der Operation prophylaktisch zu sanieren.Patienten und Methode:Anhand von 92 Patienten mit bevorstehender Klappenoperation wurde die Inzidenz von Infektionsquellen im Zahn-Kiefer- und HNO-Bereich evaluiert. Als Screeninguntersuchungen wurden Zahnpanoramaschichtaufnahme mit anschließender Begutachtung durch den kieferchirurgischen Facharzt sowie ein Nasennebenhöhlenröntgen durchgeführt. Als dentaler Fokus galten periapikale Beherdung, Zysten und Wurzelreste. Im Nasennebenhöhlenröntgen wurde primär jede Verschattung als pathologisch gewertet und zu einer weiteren Abklärung dem HNO-Facharzt zugeführt.Ergebnisse:49 von 92 Patienten (53,3%) wiesen bei der routinemäßigen Fokussuche einen pathologischen Befund auf. 42 Patienten (45,6%) zeigten einen behandlungsbedürftigen dentalen Infektionsherd, bei 19 Patienten wurden Verschattungen im NNH-Röntgen beschrieben (drei Aspergillome, drei Sinusitiden, die restlichen Verschattungen wurden als chronische, präoperativ nicht behandlungsbedürftige Polyposis befundet). Zwölf Patienten hatten sowohl im Kieferstatus als auch im NNH-Röntgen Auffälligkeiten. Die Blutsenkungsgeschwindigkeit korrelierte weder mit Kiefer- noch mit HNO-Herden. Dentale Foci fanden sich am häufigsten bei Patienten mit geplantem Mitralklappenersatz (MKE) (61%, davon 2/3 mehrere Herde). Von den Patienten mit anstehendem Aortenklappenersatz (AKE) hatten 47%, Mehrfachklappenersatz (MKE) 50%, MKE plus ACB (aortokoronare Bypassoperation) 50% und AKE plus ACB 40% sanierungsbedürftige Foci.Schlussfolgerung:Durch die präoperative Fokussuche bei einem unerwartet hohen Prozentsatz der Patienten konnten bakterielle Herde diagnostiziert werden. Letztendlich fehlen allerdings prospektive Daten, die untermauern, dass durch die Herdsanierung die Inzidenz der Prothesenendokarditis reduziert werden kann.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 peridontitis, 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 chronical 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.