In the present investigation the frequency of oral ulcers and pain in 161 orthodontic patients was recorded. Of all patients, 95% had experienced pain, but 84.5% said that the pain lasted a few days only. About 11% maintained that the treatment was constantly painful. Significantly more patients coming from private clinics complained of pain than those attending treatment at the Department of Orthodontics. About 50% said that activating or changing archwire was most annoying, whereas 28.7% said ulceration and 21% said headgear was the most annoying part of the treatment. According to 75% of the patients, sleeping habits were not influenced. Only eight patients reported truancy, and seven of these had done this only once. Of all patients, 6.2% had requested interim visits. Small wounds caused by the fixed appliance were reported by 75.8% of the patients, and 2.5% had suffered badly from ulceration caused by the fixed appliances. More girls than boys reported ulceration. There was a significant sex difference as regards recurrent aphthous ulceration (RAU). Increase in the frequency of RAU was reported by 23.1% of the girls and 9.6% of the boys while they had fixed appliances.

In the present investigation the frequency of oral ulcers and pain in 79 adults orthodontic patients was recorded. Only four of all patients had never had oral ulceration during treatment, but 83% of the patients characterized the trouble as minor. About 47% of the patients said that ulcers caused by the fixed appliance were the most annoying part of the treatment, and 38% said that activation of the appliance caused the most discomfort. In about 63% of the patients there was less pain when the treatment had lasted for some months, and in 24% there was no significant change in the discomfort. The pain following activation lasted for only 2-3 days (71%), but 20% had pain for more than 3 days, and five individuals felt pain constantly. The recurrence of aphthous ulceration (RAU) was not significantly affected during the orthodontic treatment, and in only one case was there an increase in the occurrence of herpes labialis.

– The pressure side of human, premolars subjected to experimental movement for 5–76 d were studied in the scanning electron microscope. Sham‐operated and untreated premolars were used as controls. In order to study the morphology and occurrence of root resorptions, the organic tissue was removed using 1:2 diamino ethane or sodium hypochlorite and the denuded root surfaces were re‐examined in the scanning electron microscope. Areas of compressed soft tissue were regularly present and the size, shape and number of such zones varied in the experimental groups. Initially, tissue affected by pressure was mainly located in the marginal region and subsequently the mid‐portion of the roots became generally influenced. Removal of hyalinized tissue started shortly after the formation, and during this soft tissue removal the underlying hard tissue was resorbed. Observation of circumferentially removed, coalesced fibers corresponded with the finding of extensively resorbed lacunae in the mineralized tissue beneath. The resorptive processes of the cementum began after 10 d as round cavities measuring about 6 μm. Further resorption in cementum was characterized by numerous small, thin‐walled round lacunae which confluenced into extensive, shallow resorptions after 20 d. Dentin was distinguished by the presence of tubules, and in sites of active resorption removal of mineral crystals had occurred, exhibiting a latticed fiber arrangement.

Playing wind instruments requires increased ventilation and increased orofacial muscle activity. The aim of the present investigation was to study the longitudinal effects on the dentofacial morphology of increased ventilation and orofacial muscle activity associated with playing wind instruments. Lateral cephalograms and dental casts obtained from wind instrument players at the ages of 6, 9, 12, and 15 years were studied and compared to control groups. In addition information was obtained as to how many hours per day they practised their instruments. Significant differences between the musicians and controls were found. The musicians had a decreased anterior facial height and wider dental arches. The findings are interpreted as being due to increased orofacial muscle activity and increased intra-oral pressure resulting from wind instrument playing.

The anatomy and the concomitant function of the face seem to be reciprocal issues. Previous studies have shown that stenosis in the posterior part of the nose, hampering nasal air flow, is associated with a retrognathic face and a posterior rotation of the lower jaw, i.e. components of the adenoid syndrome. The present study examines facial cephalometric morphology in adults with a deviated nasal septal cartilage, i.e. an anteriorly positioned nasal stenosis. Compared to a group of unafflicted individuals, also with regard to rhinomanometric resistance, a significantly smaller posterior facial height, smaller height of the anterior nasal aperture, a posterior rotation of the lower jaw and a shorter nasal floor and ceiling were found. This may mean that growth of the nasal septal cartilage and growth of the surrounding skeletal areas are out of step. A relatively undersized skeletal frame, in the sagittal plane, may have led to the buckled non-fitting septal cartilage, with increased air flow resistance as a secondary effect. If this interpretation is correct, an early cautious surgical correction of the septal deviation, also balancing this growth incongruence, might be worth serious consideration.