Enamel hypomineralization in permanent first molars. A clinical, histo-morphological and biochemical study

Hypomineralization in the permanent first molars was common in a group of 516 Swedish 8-year-old children. Ninety-five children (18.4%) had at least one molar with demarcated opacity. The incisors frequently displayed opacities concomitantly. The mean number of hypomineralized teeth of the affected children was 3.2 (SD 1.8), of which 2.4 were first molars. Six and a half percent of the children had severe defects, 5% had moderate defects, while 7% had only mildly hypomineralized teeth. Fifteen percent had more than one tooth affected, indicating systemic causation. The affected children, especially the boys, were reported to have had more health problems, asthma in particular (but only 4 cases), during the first year of life. Breast feeding history was similar in children with and without enamel defects. The children with severely defected enamel had undergone dental treatment of their first molars nearly ten times as often as the children in the healthy control group at the age of nine. Behavior management problems and dental fear and anxiety were common compared to the controls.Undemineralized sections from 73 permanent first molars, extracted due to severe hypomineralization of the enamel, were examined in polarized light. The hypomineralized areas extended from the cusps cervically comprising about half of the buccal and lingual sides. The cervical border to normal enamel was well defined and mainly followed the lines of Hunter-Schreger. The hypomineralized zones were covered by thin well-mineralized enamel. The concentration gradients for F, Cl, Na, Mg, K and Sr in hypomineralized enamel were analyzed by means of Secondary Ion Mass Spectrometry (SIMS), and completed with an analysis of the main matrix elements O, P and Ca by means of X-ray microanalysis (XRMA). Hypomineralized enamel had a higher content of C. Ca and P concentration were lower compared with normal enamel. The mean Ca/P ratio in hypomineralized areas was significantly lower (1.4) than the mean Ca/P ratio in the adjacent normal enamel (1.8)

Pain sensation and injection techniques in maxillary dento-alveolar surgery procedures in children : a comparison between conventional and computerized injection techniques (The Wand)

Local anesthesia, especially palatal injection, is often associated with fear and anxiety. The aim was to compare the sensation of pain when using palatal block technique with computerized injection technique (CIT), to conventional infiltration technique with traditional syringe in surgical procedures involving the palate. Patients referred for bilateral minor maxillary surgical treatments were randomized for traditional infiltration anesthesia on one side and palatal block anesthesia with CIT on the other side. AMSA and P-ASA approaches were used with CIT. The sensation of pain was scored by the VAS scale. Twenty-eight patients were included in the study, where of 17 (61%) were girls. The median age was 14.8 yrs. (12.6 - 17.8). Bilateral exposure of palatal impacted canines was the most common treatment. The injection pain was significantly lower, (p = 0.009), when using the CIT injection compared to conventional injection. However, with time-consuming surgery, additional CIT analgesic solution had to be injected in the buccal gingiva when suturing, in one fourth of the cases. Patients sedated with nitrous oxide seemed to benefit less from CIT. Computerized injection techniques, including P-ASA and AMSA approaches, reduces the sensation of pain when carrying out less time-consuming palatal dental surgery, especially in non-sedated teenagers