Biomedical subjects

T Lauc

Publications and source records attributed to T Lauc.

5 recordsLinked to original sources

PubMed2003

Effect of inbreeding and endogamy on occlusal traits in human isolates.

OBJECTIVE: To discuss the genetic basis of occlusal traits through analysis of the effects of inbreeding in a subdivided isolated community. SUBJECTS AND METHODS: The sample comprised dental casts of 224 children, aged 7-14 years, from 15 villages of the Island of Hvar, Croatia. MAIN OUTCOME MEASURES: Studied traits were Angle class, overjet, vertical bite, overbite, and crowding/spacing. DESIGN: Children with complete grandparental endogamy (all four grandparents born in the village of residence of the examinee) were compared to children with incomplete grandparental endogamy. In addition, children resident in the group of villages with a high prevalence of inbreeding were compared to children resident in the groups of villages with moderate and low prevalence of inbreeding. RESULTS: In both designs, inbreeding seemed to increase the mean values of overjet, overbite, and vertical bite, while it had little or no effect on crowding/spacing. Angle classes were correlated to inbreeding at the individual level, but this was not supported at the population level. The effects were stronger in the subsample with bilaterally concordant Angle classes. CONCLUSION: The observed inbreeding effects imply that the genetic basis of some occlusal traits is polygenic and, in considerable part, influenced by rare and recessive genetic variants.

Adolescent↗

PubMed2000

Orofacial analysis on the Adriatic Islands: 1. The island of Hvar as a model for odontogenetic researches.

This paper presents a preliminary orofacial analysis of a subadult population of Hvar, a Croatian island in the Adriatic. Its population represents one of the last genetic isolates in Europe and has therefore been the object of intensive crossdisciplinary research over the last 30 years. We focussed on the coefficient of endogamy on the one hand and malocclusal-related caries on the other hand, and expected differences in the latter between subgroups of the population. We analyzed 224 dental casts from children all over the island and found multiple caries in approximal surfaces in 55 percent of the children, but no significant differences between the subpopulations. Instead, significantly more caries affection was found in the boys than in the girls. The percentage of general caries affection is fairly high, even when compared to other isolated populations; it may be due to environmental influence. This would be consistent with the other results, which have putatively been caused by complex environmental influences and not solely by genetic components.

Adolescent↗

PubMed2000

Implant failure: regional versus cumulative evaluation.

In this paper the success rate of implant therapy in various bone regions is discussed. The objective is to determine whether differences existed in success rates of cylinder implants placed in different areas in the both maxilla and mandible. Forty four patients have been treated and reviewed five years after the placement of the fixed prosthetic restoration. The patients were provided with a total of 92 implants. Results from this study show very low survival rate for implants placed in anterior region of maxilla (55.6%) after five years. It is concluded that simple cumulative follow up studies do not entirely correspond to actual situations, positioning the implants has an important role in the planning of the implant therapy and that important factor for force compensation is not only the surrounding bone density, but also the region of the jaw where the implants are placed.

Adult↗

PubMed1999

Computer analyses of two active plate modifications.

The aim of this study was to determine tooth movements in the upper dental arch using a simulated original model during the time of activation of two active plates modifications, symmetrically and asymmetrically cut plates. The changes of the dental arch dimensions and precise evaluation of the distribution of the forces produced by appliance were analysed by recording tooth movements. In order to register tooth movements more precisely two referral points were notched on each tooth thus creating 38 variables which defined weight and lengths of the dental arch. The symmetrically cut active plates used to obtain transversal expansion affect equally both sides and cause symmetrical movements of premolars, less of molars and canines, whereas they have no effect on incisors. The asymmetrically cut active plates used to obtain transversal expansion affect more the side of smaller active part of the plate. Movements are larger at the premolars than at molars and canines, and minimal at incisors. The results of this study confirm the data from the literature and a logical interdependence of the force and movements thus emphasising the importance of anchorage in orthodontic therapy.

Computer Simulation↗

PubMed1998

Early post-operative complications in oral implantology.

Hematoma, postoperative bleeding, edema, early infection, dehiscence, emphysema, air embolism, loss of primary stability of the implant, acute sinusitis, postoperative cutaneous or mucosal anesthesia and loss of central visual field are early postoperative complications. The incidence of early post-operative complication during the first days of postoperative follow-up was inquired. Eleven patients were implanted by 27 DPI implants. The patients were followed up the first day, the second day and the tenth day after the one-phase surgical technique. Dehiscence in 2 patients, edema in 10 patients, hematoma in 2 patient and postoperative bleedings in 3 patients were established. Three implants were removed because loss of primary stability. It is indicated that by proper preoperative and intraoperative as well as postoperative approach it is possible to influence early postoperative complications. Even though postoperative complications are sometimes unavoidable, choosing the most appropriate surgical technique and keeping oral cavity hygiene are the most important factors in prevention. It is concluded that only the loss of primary stability is incorrigible and successes of implanto-prosthetic rehabilitation can be properly and fully evaluated only after 5 to 10 years of follow up period.

Adult↗