Nina von Wowern

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.

General and oral aspects of osteoporosis: a review.

Abstract. This review comprises a short summary of up-to-date clinical knowledge on systemic osteoporosis in order to focus on the clinical dental studies on osteoporosis of the jaws, which have become available within the last 15 years . Diagnosis of jaw osteoporosis requires assessment of the bone mineral content (BMC)/density (BMD) using specially constructed jaw bone scanners and development of a corresponding gender-related set of normal BMC/BMD values for young adults, as in other sites of the skeleton. If other factors are excluded, jaw osteoporosis may involve the risk of minor accentuation of alveolar bone loss after wearing a full denture, in cases of periodontitis and in peri-implant areas. However, implant-supported overdentures conserve bone because of their positive load-related effect on the jaw. Estimation of BMC/BMD is also advisable for edentulous osteoporotic patients. Systemic treatment involving the bone metabolism affects the jaw BMC/BMD positively or negatively as in other skeletal sites, but the magnitude of this effect is site-specific. Future studies of the effect of bisphosphonates on the jaw BMC and alveolar bone loss, and analyses of the bone quality and jaw BMC/BMD in relation to implant treatment, without or with bone transplantation, are required.This review comprises a short summary of up-to-date clinical knowledge on systemic osteoporosis in order to focus on the clinical dental studies on osteoporosis of the jaws, which have become available within the last 15 years . Diagnosis of jaw osteoporosis requires assessment of the bone mineral content (BMC)/density (BMD) using specially constructed jaw bone scanners and development of a corresponding gender-related set of normal BMC/BMD values for young adults, as in other sites of the skeleton. If other factors are excluded, jaw osteoporosis may involve the risk of minor accentuation of alveolar bone loss after wearing a full denture, in cases of periodontitis and in peri-implant areas. However, implant-supported overdentures conserve bone because of their positive load-related effect on the jaw. Estimation of BMC/BMD is also advisable for edentulous osteoporotic patients. Systemic treatment involving the bone metabolism affects the jaw BMC/BMD positively or negatively as in other skeletal sites, but the magnitude of this effect is site-specific. Future studies of the effect of bisphosphonates on the jaw BMC and alveolar bone loss, and analyses of the bone quality and jaw BMC/BMD in relation to implant treatment, without or with bone transplantation, are required.

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.

Closure of oroantral fistula with buccal flap: Rehrmann versus Môczár

Abstract A prospective follow-up study of 90 patients with oroantral fistula, persisting for 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 Moczar-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 Moczar flap (n=20). PP included: a rhino-laryngologic 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 Moczar flap is minimal; (6) scar tissue at the anterior incision of a Moczar flap is a frequent finding; (7) why a Rehrmann flap is the treatment of choice for patients with natural teeth and a Moczar flap for edentulous patients.

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.

Bone loss and oral state in patients on home parenteral nutrition

BACKGROUND The purpose was to analyze changes in the mandible and the forearm bone mineral content and oral state in patients on home parenteral nutrition due to short bowel syndrome in relation to the bone mineral values and oral findings in a normal population. METHODS The bone mineral content was measured by dual-photon absorptiometry and the dental and periodontal state were studied in 15 adults patients (12 women, and 3 men, aged 26 to 65 years). All patients were on free oral intake as a supplement to the parenteral nutrition. RESULTS Forty-seven percent of the patients (2 males, 2 young and 3 elderly females) showed mandibular osteoporosis (Z-scores < -2.00), and all young females showed Z-scores < 0. Moreover, 34% of the patients showed osteoporosis in the forearm bones (Z-scores < -2.00) and also radiographic signs of osteoporotic fractures of the columna. The dental and the periodontal state in the patients did not differ clearly from that of the normal Danish population of the same age. CONCLUSIONS Such patients seem to have a high risk of developing systemic osteoporosis, including the jaws, but apparently do not show a higher risk for deterioration of the dental or periodontal state than age-matching normals from the same population.

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.

Bone mineral content in medieval Greenland Norse

The bone mineral content (BMC) was measured using a special dual-photon scanner in 25 mandibles with normal macroscopic and radiographic bone structure. The mandibles were excavated from two Norse sites in Greenland, which date to the first and last part of the medieval Norse settlement period, respectively. The main purpose of this study was to investigate whether there was a change in BMC levels between the early and the late settlement period. The results showed no difference in male BMC between the early and the late site material. A statistically significant gender difference was found, analogous to most clinical and archaeological BMC studies. The sample did not allow testing for age-related, especially female postmenopausal-related, bone loss. It is known that Eskimos generally have a very low BMC, probably the effect of a high-protein marine diet. The lack of decrease in BMC levels for the Norse could indicate that they did not increase their overall protein intake over the 500-year settlement period. Other studies (both archaeological and anthropological) point to an increased reliance on marine foodstuffs throughout the settlement period. Thus, if the Norse increased their reliance on marine foodstuffs, they probably did not do so to the extent of an almost exclusive marine diet like that of the Eskimo.