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N von Wowern

Publications and source records attributed to N von Wowern.

At least 19 recordsLinked to original sources
PubMed1992

Symptomatic osteoporosis: a risk factor for residual ridge reduction of the jaws.

The purpose of this study was to clarify if symptomatic osteoporosis is a risk factor for severe residual ridge reduction of the jaws. The analysis included 12 edentulous women with osteoporotic fractures, otherwise normal, and 16 normal edentulous women matched with respect to age, menopausal age, and period of edentulousness. The bone mineral content measured in vivo by dual-photon scanner was significantly lower in the mandible and the forearm bones (that is, in the skeleton) of the osteoporotic group than it was in the normal group. No significant difference between the two groups was demonstrated with respect to the size of the mandibular sagittal area, measured on identical lateral cephalograms, while the sagittal maxillary area was significantly smaller in the osteoporotic group. Symptomatic osteoporosis therefore seems to be a severe risk factor for smaller residual ridge reduction off the maxillae, while this does not seem to be the case in the mandible.

Aged↗
PubMed1992

Steroid-induced mandibular bone loss in relation to marginal periodontal changes.

Long-term high-dose glucocorticosteroid treatment may be suspected as causing profound marginal periodontal bone loss due to the immunosuppressive/antiinflammatory effects and due to the osteoporotic side-effects. This study comprised an analysis of the loss of the mandibular and forearm bone mineral content (BMC), measured in vivo by dual-photon scanner, in relation to the concomitant changes of the periodontal indices (visible plaque, gingival bleeding, loss of attachment) in 17 acute nephrotic dentate patients undergoing intensive steroid treatment for 12 months. The measurements were performed at start of treatment, when all patients were considered healthy as regards the skeleton, and at the 6-month and 12-month follow-up. The mean BMC loss at the standard sites of the mandible and the forearm bones was 5.6%/year at both sites. No significant changes could be demonstrated in the periodontal indices (P greater than 0.10), and no relation was found between the mandibular BMC loss and the periodontal condition (R = 0.06, P greater than 0.10). In conclusion, profound marginal periodontal bone loss does not seem to be a prominent side-effect of long-term glucocorticosteroid treatment, although the degree of induced osteopenia in the mandible corresponds to that in other cortical bones of the skeleton.

Adult↗
PubMed1991

The mandibular bone mineral content in relation to vestibulolingual sulcoplasty. A 2-year follow-up.

The bone mineral content (BMC) in mandibles can now be measured in vivo with high precision by a specially constructed dual-photon scanner. This study analyzed, over a 2-year period, the BMC loss of endentulous mandibles in a group of young and older women after vestibulolingual sulcoplasty with free skin grafts, and its relationship to the initial mandibular BMC and the age-related mandibular BMC loss. BMC in the denture-wearing site and the standard site of the mandible was measured by this method. A significant negative relationship was found between the initial BMC values in the standard site and the BMC loss (in percent) in the denture-wearing site in both age groups, and a significant positive relationship between the BMC loss (in percent) in the two sites of the mandible in the elder group. The rate of residual ridge reduction may be predicted from the initial mandibular BMC value and seems to be dependent on the age-related mandibular BMC loss.

Adult↗
PubMed1990

ITI implants with overdentures: a prevention of bone loss in edentulous mandibles?

Changes in the bone mineral content (BMC) of edentulous mandibles with osseointegrated ITI implants supporting overdentures were measured in vivo by dual-photon absorptiometry. The BMC measurements were performed 3 weeks postoperatively and at the 2-year follow-up visit. Measurements were made in the ITI site (anteriorly), the premolar region just behind the fixtures, and the standard site of the mandible for obtaining reference values of the age-related MBC loss. The increased function of the mandible after this treatment seems to cause a load-related bone formation that minimizes, or in some cases may counteract, the physiologic age-related BMC loss leading to osteoporosis.

Absorptiometry, Photon↗
PubMed1990

A radiographic four-year follow-up study of asymptomatic mandibular third molars in young adults.

Fifty-five asymptomatic mandibular third molars (M3) in 34 dental students (mean age 20.6 years at the start of the study) were followed radiographically for 4 years. Based on clinical evaluation the 55 teeth included 20 almost erupted, 13 partly erupted and 22 non-erupted M3. The following were assessed on the radiographs: root development, level of eruption, sagittal angulation, resorption, pericoronitis/bony pockets/paradental cysts and widening of the periodontal space/dentigerous cysts. The state of 21 teeth (38 per cent) was radiographically changed at the end of the observation period. The most remarkable finding was that 15 teeth changed their sagittal angulation, all in a distal direction; five mesioangular to vertical, five vertical to distoangular, five mesioangular to distoangular. Radiographically, 13 M3 moved to a more advanced level of eruption. No real pathological osseous lesions and no root resorption were observed at initial or follow-up examinations. It is concluded that there are frequent essentially unpredictable changes in the position of M3 after the age of 19 years which may influence decisions on their removal or preservation.

Adult↗
PubMed1989

The fate of impacted lower third molars after the age of 20. A four-year clinical follow-up.

Seventy dental students (mean age: 20 years) with 130 asymptomatic, non-ectopic, impacted mandibular 3rd molars were followed for 4 years. At the initial visit 26 were impacted in soft tissue, 30 were partially impacted in bone, and 74 were completely impacted in bone. The following items were registered at each visit: regional pocket depths, signs and symptoms of pathology, degree of impaction, presence of upper 3rd molar. No signs or symptoms of pathology were observed in any of the subjects at the 2 visits. The 4-year visit revealed that 49 3rd molars had been removed, the reason being pericoronitis or caries in 30%, mild symptoms in 39% and for prophylactic reasons in 31%. Of the remaining 81 3rd molars: 71% of the soft tissue impactions, 25% of partial bony impactions, and 8% of complete bony impactions showed complete and normal eruption. The remaining 3rd molars were either static or had advanced in the degree of eruption. It is concluded that non-ectopic, impacted 3rd molars in the given age group may have a chance to completely erupt. The treatment for asymptomatic impacted 3rd molars in young adults, therefore, might be observation instead of prophylactic removal.

Adult↗
PubMed1988

Bone mineral content of mandibles: normal reference values--rate of age-related bone loss.

The purpose was to obtain the normal sex- and age-related reference values for the bone mineral content (BMC) in the bones of the mandible and the forearms, as estimated by dual-photon absorptiometry; to examine the effect of tooth loss on the mandibular BMC, i.e., BMC in the basal part of the mandible; and to analyze the rate of the sex- and age-related BMC loss in the mandible in normal old edentulous individuals greater than or equal to 70 years of age and its relationship to the corresponding BMC loss in the forearm bones. The following groups were measured: young dentate adults (n = 100; women (W): men (M) = 1:1), young, long-term edentulous W (n =15), and old edentulous individuals (n = 24 W, 10 M). In the old group the BMC measurements were repeated after 2- or 3-year period (n = 18 W, 10 M). The analyses indicate that the mandibular BMC reference values differ by sex and age; but correction for the state of dentition seems of minimal benefit. The average BMC loss (%) in the bones of the mandible and the forearms seems to be higher in old W (1.5 and 1.4% per year) than in old M (0.9 and 0.7% per year), but of the same magnitude in each sex. The relationship between the BMC loss (%) in the two sites was significant (P less than 0.01) but rather weak. Thus, it seems important to follow the sex- and age-related BMC loss in the mandible separately.

Adult↗
PubMed1988

Bone mineral content by photon absorptiometry of the mandible compared with that of the forearm and the lumbar spine.

A new method for measuring the bone mineral content (BMC) of the mandible by dual-photon absorptiometry (DPA) has recently been introduced. The purpose of the present investigation therefore was to examine the long-term precision for 32 months in vitro and in vivo for assessment of BMC in the mandible and to examine the relationship in vivo among BMC of the mandible, the forearms, and the lumbar spine as measured by DPA and/or single-photon absorptiometry (SPA). For comparison, the relationship between forearm BMC as measured by DPA and SPA was studied. The long-term precision of the mandibular BMC was 0.8% in vitro, independent of age and change of radioactive source, and 2.1% by assessment in vivo. A significant relationship (P less than 0.01) was found between BMC of the lumbar spine and the forearms and between the two sets of forearm BMC measured by DPA and SPA. Thus, relative BMC changes of the forearms can be compared without respect to type of forearm bone scanner used. The BMC changes of the mandible can only be evaluated by scanning of the mandible itself. The present DPA bone scanner is suitable for follow-up analyses of the BMC changes of the mandible and the forearms.

Adult↗
PubMed1988

Bone mineral content of the maxilla estimated by dual-photon absorptiometry after augmentation with bone or hydroxyapatite.

A new, precise, non-invasive method for measuring the bone mineral content (BMC) of the mandible in vivo by dual-photon absorptiometry has recently been introduced. The purpose of the present analysis was to examine the precision in vitro and in vivo and the accuracy in vivo for assessment of BMC in the maxilla. The precision was determined by repeated measurements in vitro on a cranium and in vivo on two test persons with and without a bone specimen fixed to a palatal plate. The accuracy in vivo was determined from the BMC measurements of the two test persons and of nine edentulous persons, scanned before and after augmentation of the maxillary alveolar ridge with hydroxyapatite. The analyses indicated that the precision for maxillary BMC assessments was high (0.9% in vitro and 2.0% in vivo) and the accuracy in vivo was 6.6%, corresponding to the accuracy in vitro for skeletal BMC measurements by dual-photon absorptiometry. The present method therefore seems to be well-suited for follow-up analyses of the BMC changes in the jaws after augmentation of the alveolar ridges with bone or hydroxyapatite.

Alveolar Ridge Augmentation↗
PubMed1987

[Sinus pain].

Explore the source record for details and available documents.

Facial Pain↗
PubMed1985

In vivo measurement of bone mineral content of mandibles by dual-photon absorptiometry.

The purpose of this study was 1) to reveal the short- and long-term precision of noninvasive in vivo measurements of bone mineral content (BMC) in larger and smaller parts of mandibles and in forearm bones by a new two-dimensional dual-photon attenuation system GT45; 2) to develop normal reference values and ranges for mandibular BMC in individuals between 20-40 yr of age without known systemic diseases and with normal oral state, (n = 56, F:M = 1:1), and 3) to relate mandibular BMC with forearm bone BMC, sex and age, by comparing BMC values of a well-defined normal old test group (n = 24, F:M = 1:1, 70-81 yr of age) with the normal reference values. The analyses indicated: 1) the in vivo short- and long-term precision of the methods is high. 2) BMC of mandibles and forearm bones is significantly related to sex and age (P less than 0.01, and in mandibles of young females/males: P = 0.02). 3) BMC in mandibles and forearm bones is significantly correlated in both age groups (P less than 0.01) with relatively weak coefficients of correlation. GT45 may be used to follow BMC changes in mandibles in groups or single individuals after surgical treatment and to evaluate sex and age dependent BMC changes in mandibles and forearm bones.

Adult↗
PubMed1982

Closure of oroantral fistula with buccal flap: Rehrmann versus Môczár.

A prospective follow-up study of 90 patients with oroantral fistula, persisting for greater than or equal to 10 days, closed with a buccal flap and with systemic penicillin therapy has been carried out. The purpose was: (1) to compare the results after closure with a Rehrmann- and a Môczár-buccal flap; (2) to elucidate the reasons for failures; (3) to clarify when and why a permanent reduction of the vestibular height may occur after the use of buccal flaps. The material was divided into two groups: preoperative preparation (PP) group: 52 cases, closed with Rehrmann (n = 32) and Môczár flap (n = 20). PP included: a rhino-laryngeal examination and an antral irrigation. Follow-up period: 6-12 months. No PP group: 38 Rehrmann flap cases without PP, and followed for 2 months. The analysis shows: (1) the result of closure is independent of the choice of flap; (2) the risk of failure is negligible by careful regimens (elimination of active maxillary sinusitis before/after closure, avoiding sneezing); (3) uneventful repair for 2 months means permanent repair; (4) flattening of vestibulum for 2 months results in a persistent condition; (5) permanent flattening of the vestibulum will occur in about half of the Rehrmann flap cases, independent of the state of dentition or buccal alveolar bone loss; the risk of this complication after a Môczár flap is minimal; (6) scar tissue at the anterior incision of a Môczár flap is a frequent finding; (7) why a Rehrmann flap is the treatment of choice for patients with natural teeth and a Môczár flap for edentulous patients.

Adolescent↗
PubMed1981

Submergence of roots for alveolar ridge preservation. A failure (4-year follow-up study).

A 4-year clinical and radiographic follow-up study of 20 cases of crown-resected root-filled roots, covered by mucosal flaps, distributed among 15 patients, has been carried out. Only cases of uneventful submergence of the root with intact healthy mucosa were regarded as successful. This study shows that: (1) The number of failures increases with the years; from 3 cases at the 1-year to 11 cases at the 4-year follow-up, corresponding to 53% (8/15) of the patients. In the failures, an exposure of the root-surface was seen, but without inflammation in the surrounding tissue. These roots could be extracted without bone loss. (2) Alveolar ridge atrophy is not prevented by retained roots, and is probably the primary reason for failure of coverage. The 11 failures showed alveolar ridge atrophy, which was observed before failure in 6 cases. None of the successful cases showed alveolar ridge atrophy. The present method cannot be recommended as a routine procedure.

Alveolar Process↗
PubMed1981

Clinical and radiographic findings in maxillary sinus with oro-antral fistula.

The purpose of the present study was to estimate: (1) the diagnostic value fo the primary clinical and radiographic examinations as to the condition in the antral mucosa in cases of an oroantral fistula; and (2) the value of a radiographic follow-up of cases with uneventful, successful surgical closure of the fistula. The material consisted of 52 patients with an oro-antral fistula. The condition of the antral mucosa was examined before and during the surgical operation. Postero-anterior and lateral radiographs of the paranasal sinuses, orthopantomograms and intraoral dental films were taken of each patient and also in 10 cases of uneventful, successful closure after 1 year. This analysis shows that: (1) the primary clinical diagnosis of the condition in the antral mucosa corresponds to the real diagnosis; (2) false negative radiographs are rare; (3) false positive radiographs will occur in 22% - 63% of cases without maxillary sinusitis; and (4) radiographic follow-up of uneventful, successful cases can be omitted. In conclusion, the primary clinical examination is most reliable and superior to radiographs in proof/disproof of maxillary sinusitis, pre- and postoperatively.

Adolescent↗
PubMed1980

Pattern of age related bone loss in mandibles.

A study was carried out to analyze the pattern of the age related bone loss in the mandibular cortex and to establish normal values and the observed range of morphometric variables on microradiograms of bone sections taken from a well defined site anterior to and below the mental foramen. Specimens were obtained from 100 Danish subjects with no known systemic bone disease or severe mandibular atrophy. Microradiograms of 100-micron-thin undemineralized vertical ground cross-sections were produced. An electric point-counting system was used for the determination of 1) percentage bone mass, 2) mean cortical width (MCW), and 3) the percentage of Haversian canals with resorption surfaces. The analysis showed that cortical porosity and the percentage of Haversian canals showing resorption are unrelated to sex and increased after the age of 50. MCW and absolute bone mass (MCW x % bone mass) are greater in males than in females and show a parallel age related decrease after the age of 50. Furthermore, the age related increase in cortical thinning and porosity is dependent on the individual as well as on age. Marked individual variation confined the use of these parameters to group analysis.

Adult↗
PubMed1979

Changes in bone mass in rat mandibles after tooth extraction.

An experimental study concerning changes in bone mass in trabecular bone of mandibles on rats after extractions of upper molars has been carried out. The material consisted of 32 SPF Wistar rats, fed on Nafag-184 only. Experimental and control groups consisted of eight females and eight males, each group having same average weight with respect to sex at the age of 16 weeks. At this age the upper right molars were extracted on all rats in the experimental group. The rats were sacrificed after 16 weeks. Identical increase in weight within each sex group was found. Microradiograms of two buccal-lingual 100-mu-thick ground sections at a distance of 0.5 mm through the first molar in each side of the mandible were used. Quantitation of bone mass (bone area in percent) of a trabecular bone was done by electronic point counting. No significant difference in bone mass was found between left and right sides in the control group (P greater than 0.50), whereas a significant difference was found between left and right sides in the experimental group (P approximately 0.0001) with lowest mean value in right sides. Conclusively the analysis shows that local reduction in bite force causes osteoporotic changes in trabecular bone of the jaw.

Animals↗