Olav Egil Bøe

Frequency of hypodontia in relation to tooth size and dental arch width

This study describes the frequency of hypodontia among all the children of the same age group in a Norwegian municipality and reports variations of some dimensions of the dentition associated with hypodontia. Congenitally missing permanent teeth, not including third molars, were found in 7.1 per cent of the material at age seven, and in 6.6 per cent at age nine. The difference seemed to be due to insufficient mineralization of the second lower premolars in boys at age seven. The frequency of hypodontia per se was a little higher in girls than in boys, and the girls were missing more teeth per individual. Neither the dental arch width nor the mesiodistal diameter of the teeth were significantly different in the hypodontia group compared to a control group without hypodontia.

Predictor evaluation of postoperative morbidity after surgical removal of mandibular third molars

The effect of several pre- and per-operative variables on indicators of postoperative morbidity was assessed in 204 patients after unilateral mandibular third-molar surgery. The variables included gender, age, use of tobacco and alcohol, state of eruption, depth and angulation of the tooth, duration of the operation, pericoronitis, and time of day of surgery. Visual analogue scales were used for patient assessment of pain and swelling and for clinical assessment of swelling. Maximum pain was indicated 6 h postoperatively and maximum swelling the first postoperative evening. The results showed a mean reduction of mouth opening capacity (trismus) of 31% the 1st postoperative day. Mean analgesic consumption was 3.7 tablets, mean number of days of inability to work 1.1, and the rate of postoperative alveolitis 1.9%. The variation of the morbidity indicators was considerable. Multiple classification analyses showed that the predictors explained from 17% (clinically assessed swelling) to 8% (pain 6 h postoperatively) of the variance of these indicators. It is concluded that these commonly used predictors only to a minor extent can explain the wide variation in postoperative morbidity after mandibular third-molar surgery.

Orthopedic protraction of the upper jaw in cleft lip and palate patients during the deciduous and mixed dentition periods in comparison with normal growth and development.

Cleft lip and palate (CLP) patients often develop maxillary retrusion after cleft repair. Since 1977, a group of 98 cases with negative overjet (anterior crossbite) during the period of deciduous dentition has been treated by the Bergen CLP team. The purpose of treatment has been to achieve favorable occlusion with positive overjet and overbite by means of anterior orthopedic traction (protraction). The average age at start of treatment was 6 years 11 months, and mean treatment duration was 13 months. The protraction force was 700 g. The serial lateral cephalograms of the treated CLP group were compared with those of a noncleft group with normal growth. Normalization of the sagittal maxillomandibular relationship (ANB angle) was achieved. Significant changes were a more anterior position of the upper jaw, and a more posterior position of the lower jaw, due to mandibular clockwise rotation. The variation was considerable. This paper reports the overall changes in the whole CLP group (ALL-C group).

The effect of maxillary protraction on front occlusion and facial morphology

The intention of this work was to study the dentoalveolar and basal jaw changes in a group of children (aged 5-10 years) with nonforced anterior crossbite treated with maxillary protraction from a face mask and to compare the changes with those found in a control group with normal dentoalveolar and basal maxillomandibular relationship. The data were obtained from lateral cephalograms of 22 children taken before treatment, after a treatment period of 3-12 months, and after an observation period of 6-48 months. A group of children (n = 40) with normal maxillomandibular relationship served as controls. During treatment the mandibular prognathism was reduced, and a positive overjet was established in 18 children. The changes during the observation period were generally comparable to those found in the control group, and thus indicated a very small relapse tendency. The posttreatment comparison of the groups showed fewer significant differences than before treatment, indicating that the treatment had a normalizing effect not only on the negative overjet but also on the general face morphology.

The craniofacial morphology of individuals with hypodontia

This work describes the variations in craniofacial morphology in individuals with congenially missing permanent teeth with relation to facial prognathism, jaw development and inclination of the incisor teeth. Both sexes displayed significantly less upper jaw prognathism in individuals with hypodontia compared to the controls, and a less maxillary length as well. This finding was independent of whether the congenitally missing teeth were situated in the upper or the lower jaw. The upper incisors displayed greater anterior inclination in the individuals with hypodontia of both sexes.

Intercanine widening and sagittal effect of maxillary transverse expansion in patients with cleft lip and palate during the deciduous and mixed dentitions

Since 1977 cleft lip and palate (CLP) patients with maxillary deficiency have received an interceptive orthopedic treatment consisting of (a) transverse expansion, (b) protraction, and (c) fixed retention. Ideally the treatment should be completed early enough to permit spontaneous eruption of the maxillary permanent incisors into normal occlusion without orthodontic intervention. The early transverse expansion considerably increases space so that unerupted malpositioned incisors spread out spontaneously, creating optimal conditions for eruption and root formation. Dental diagnosis in the cleft areas is made easier. Posterior crossbites in 112 CLP patients were expanded with a modified quad-helix appliance cemented with four bands in the deciduous or mixed dentition. Intercanine widening was about 3 mm per month regardless of cleft type. Several authors have claimed that transverse expansion of the upper jaw will increase sagittal overjet. Other authors have not found such an effect. The sagittal effect on the maxilla was studied in 68 CLP patients who had received transverse expansion. Analysis of the lateral cephalograms revealed no significant sagittal dentofacial maxillary treatment effects involving forward movement of maxilla, but a downward clockwise rotation of the mandible was found.

Changes in craniofacial morphology of individuals with hypodontia between the ages of 9 and 16

The effect of hypodontia on the general growth pattern was studied by comparing the same hypodontia group (n female = 18, n male = 12) with a control group (n female = 12, n male - 14) at the ages 9 and 16. The length of the maxilla was shorter in individuals with hypodontia, otherwise only minor differences were observed. It thus seems that hypodontia has little effect on the general growth pattern, and that orthodontic treatment in hypodontia patients should follow the same guidelines in relation to growth as in any other children.

Comparison of two surgical methods in combined surgical-orthodontic correction of impacted maxillary canines

The post-treatment periodontal condition of impacted maxillary canines was examined in two groups of patients. In one group (n =34) the teeth were exposed in the mouth after removal of the bone and soft tissue covering of the crown. In the other group (n =22) the bone covering the crown was removed, whereafter the mucoperiosteal flap was sutured back. In both groups the orthodontic treatment procedures were basically the same. The mean treatment duration was 18 months after radical surgical exposure and 22 months after moderate surgical exposure. The teeth were examined 1-2 years after removal of the fixed appliances. Oral hygiene and gingival inflammation were approximately the same in both groups. The palatal pocket was deeper on teeth subjected to moderate surgical exposure, and the depth also varied more. The loss of fiber attachment was not significantly different except on the palatal surface, where it was greater after radical exposure and also varied more. The interdental bone height, which was measured on radiographs, varied more after radical than after moderate surgical exposure.

Expression profile of the S100 gene family members in oral squamous cell carcinomas

BACKGROUND Several of the S100 gene members have been reported to be differentially expressed in many human pathological conditions, in particular, the malignancies. Identification and quantification of the differentially expressed S100 gene members in oral squamous cell carcinoma (OSCC) might facilitate their use as potential diagnostic and/or prognostic markers or targets for therapy. METHODS we examined the expression profile of 16 members of the S100 gene family at the mRNA level by semiquantitative reverse transcription-polymerase chain reaction (sRT-PCR) in 27 cases of OSCCs/their pair-wised normal controls obtained from Sudanese patients, and confirmed the sRT-PCR results by performing quantitative real time-polymerase chain reaction (qRT-PCR) for 6 of the 16 genes examined. RESULTS With sRT-PCR, 4 (25%; S100A4, S100A6, S100A8, S100A14) out of the 16 S100 gene members examined were found to be significantly down-regulated (P < 0.05) in the tumors compared to the normal controls. None of the S100 gene members examined were found to be significantly up-regulated in the tumors. qRT-PCR results confirmed the significant down-regulation of the S100A4, S100A6, and S100A14 genes in the tumors examined. CONCLUSION S100 gene family members might play an important role in the pathogenesis of the OSCCs examined. Findings of the present work warrant in-depth studies of the S100 gene family members, in particular, the S100A4, S100A6, S100A8, and S100A14 to further understand their possible role(s) in OSCC tumorigenesis.

Er:YAG laser in the treatment of periodontal sites with recurring chronic inflammation: a 12‐month randomized, controlled clinical trial

AIM The objective of this randomized, controlled clinical trial was to compare the clinical and microbiological effects of pocket debridement using erbium-doped: yttrium, aluminium and garnet (Er:YAG) laser with conventional debridement in maintenance patients. MATERIAL & METHODS Fifteen patients, all smokers, having at least four teeth with residual probing depth (PD) ≥ 5 mm were recruited. Two pockets in two jaw quadrants were randomly assigned to subgingival debridement using an Er:YAG laser (test) or ultrasonic scaler/curette (control) at 3-month intervals. Relative attachment level (RAL), PD, bleeding on probing and dental plaque were recorded at baseline and at 6 and 12 months. Microbiological subgingival samples were taken at the same time points and analysed using a checkerboard DNA-DNA hybridization technique. RESULTS A significant decrease in PD took place in both treatments from baseline to 12 months (p < 0.01). In the control, the mean initial PD decreased from 5.4 to 4.0 mm at 12 months. For the test, a similar decrease occurred. No significant between-treatment differences were shown at any time point. The mean RAL showed no overall significant inter- or intra-treatment differences (p > 0.05). No significant between-treatment differences were observed in subgingival microbiological composition or total pathogens. CONCLUSION The results failed to support that an Er:YAG laser may be superior to conventional debridement in the treatment of smokers with recurring chronic inflammation. This appears to be the first time that repeated Er-YAG laser instrumentation has been compared with mechanical instrumentation of periodontal sites with recurring chronic inflammation over a clinically relevant time period.