Leonard Gorelick

Incidence of white spot formation after bonding and banding

White spot or areas of decalcification are carious lesions of varying extent. The incidence and severity of white spots after a full term of orthodontic treatment were studied among patients in the separate private practices of two of the authors. To establish a base line of comparison, the presence of white spots in a random sample of untreated persons was observed. The incidence of white spots among patients treated by a multibonded technique was recorded at the time of debonding. In addition, white spots were sought in the before- and after-treatment Kodachrome slides of persons whose maxillary incisors had been handed. It was found that individual teeth, banded or bonded, exhibited significantly more white spot formation than was found in the control group. For the teeth studied, there was no difference in white spot formation in those that were banded or bonded. The labiogingival area of the maxillary lateral incisors had the highest incidence of white spots. When studied by segments, the highest incidence occurred among the maxillary incisors; the lowest was in the maxillary posterior segment. No white spots were found on the lingual surfaces of mandibular canines and incisors after prolonged use of a canine-to-canine bonded retainer. These findings suggest a relationship between resistance to white spot formation and the rate of salivary flow. Despite the lack of any preventive fluoride program among the study groups, 50% of the patients demonstrated resistance to white spot formation. The obvious degree of latrogenic damage during orthodontic treatment suggests the need for preventive programs using fluoride. Further clinical research is needed.

Reducing white spot lesions in orthodontic populations with fluoride rinsing

A clinical study was conducted to determine if rinsing frequency with a neutral 0.05% sodium fluoride rinse influenced white spot lesion formation associated with orthodontic brackets. Patients from two private orthodontic practices participated. Each received home-care instructions and were told to use 10 ml of sodium fluoride rinse daily before bedtime. The rinse was supplied free of charge to determine if this affected compliance with its prescribed use. Compliance was measured by recording the number of bottles used by each patient. As assessment of oral hygiene status was conducted, and at the time of debonding, white spot lesions were recorded. Only 13% of the 206 participants fully complied with the rinse protocol; 42% of the subjects used 10 ml approximately every other day; and 45% used the rinse less frequently. A significant dose response relationship was noted in which those who rinsed at least once every other day had fewer lesions (21%) than those who rinsed less frequently (49%). It was concluded that a significant reduction in enamel white spot lesions can be achieved during orthodontic therapy through the use of a 10 ml neutral sodium fluoride rinse. The more closely patients complied with the prescribed use, the more likely they could expect a decrease in the occurrence of lesions.

The effect of a fluoride program on white spot formation during orthodontic treatment

W hite spot formation (decalcification) of the labial enamel surface subsequent to orthodontic treatment has been recognized as a problem. This has been reported as a clinical observation”* and quantitative studies on the incidence and prevention of decalcification have been reported.3-i0 Equal susceptibility to white spot formation has been reported whether teeth are banded or bonded.g There has been general agreement that the development of white spots seems to be related to (1) the retention of plaque on the gingival side of brackets or bands, (2) oral hygiene efficiency, and (3) the inherent resistance of the individual. Studies have documented the beneficial effect of preventive fluoride programs during multibanded orthodontic treatment. Such studies have reported on officeapplied and self-administered programs.5*7 However, no studies have reported on the effect of a preventive fluoride protocol during orthodontic treatment with bonded appliances; nor have there been studies reporting on the severity and prevention of white spot formation on all individual teeth. This article presents the results of a clinical study in which an experimental preventive fluoride program was routinely used in the orthodontic offices of the authors. The study was designed to provide answers to the following questions. 1. Was the preventive fluoride program beneficial in reducing the incidence and severity of white spots after full-term bonded orthodontic treatment? 2. Will such preventive efforts reduce the white

Microscopic evaluation of enamel after debonding: Clinical application

Enamel surfaces were debonded by methods recommended in the literature and found to be problematic. A new method, not previously recommended, involving the use of a green rubber wheel followed by pumice or composite finishing paste was similarly examined and found to come closest to restoring the original, natural enamel surface. A step-by-step clinical procedure was described for highly filled, lightly filled, and unfilled adhesives.

Bonding metal brackets with a self-polymerizing sealant-composite: A 12-month assessment

Data spanning 15 months and about 1,500 bands have been presented describing an effective procedure for bonding metal brackets to enamel by the acid-etch method. A sealant-composite combination for metal brackets, not previously reported, has been described. Data have also been presented showing that, for the method and material used, it did not seem to matter clinically if a 37 per cent acid were used or if, instead a 50 per cent orthophosphoric acid in a liquid or thixotropic form, applied for 2 to 2 1/2 minutes, and drying agent were used. A comparison with the Nuva system was made and a modification was described for a useful combination technique, namely, Enamel Bond-Nuva-Tach, which takes advantage of certain attributes of each.

Implications of the failure rates of bonded brackets and eyelets: a clinical study.

A clinical study of the rate of failure of bonded brackets and eyelets on primary molars was undertaken. Two groups of patients (one bonded contralaterally and the other at random) were studied for 12 to 17 months. The data support the hypothesis that one major cause of bond failure is the force of occlusion during mastication. On the basis of this finding, several clinical applications are suggested. These include rotation of second premolars, closure of extraction spaces, and the management of limited treatment of lower incisors in the presence of deep, traumatic overbite.

The Ancient near Eastern Cylinder Seal as Social Emblem and Status Symbol

Evolution chronologique des sceaux-cylindres au Moyen-Orient. Avec le temps la proportion de ces objets faits en matieriaux durs (lapis lazuli et hematite) augmente au detriment de ceux faits en steatite, albâtre ou marbre. Etude des sceaux des periodes de Jarmo, babylonienne ancienne et sassanide

Bead Manufacture at Hajar Ar-Rayhani, Yemen

Stone beads have been made and worn since the Upper Paleolithic period. Beads have been used, appreciated and collected in a variety of ways throughout history, and often served specific religious functions. The authors study the various ways beads were shaped and polished, a topic that has been largely neglected in bead scholarship.

Minoan versus Mesopotamian Seals: Comparative methods of Manufacture

In a previous article we reported a study of Ancient Mesopotamian cylinder seals. The purpose was to provide insights, based on experimental evidence for the change from stone to metal drills in seal manufacture. These findings were correlated to earlier research in which the proportion of medium and hard stone seals (Mohs 5–7) e.g. hematite, quartz, etc. to those of soft stones (Mohs 1–3) e.g. steatite, marble, etc. was documented. The time span encompassed the beginning of cylinder seal history at Uruk (4% medium and hard stone seals) at the end of the 4th millennium B.C. through the Sasanian period c. A.D. 200–600 (99% medium and hard stone seals). Inferences were drawn relating the tremendous increase in the proportion of hard stones to advances in the technology of hard stone seal manufacture. The growing fashion for hard stone seals was attributed to their desirability as status symbols as well as to economic factors. These findings and explanations in no way contradicted the important well documented multi-functional purpose of seals for legal, political, amuletic and funerary use as well as for the protection of property. The purpose of the present article is to provide comparable data for Minoan seals. We sought evidence for the following questions: (1) What was the proportion of medium and hard stone seals to soft stone seals during the time frame of Minoan history? (2) What were the tools and technology used for the manufacture of Minoan seals and how did these change over time? (3) What inferences might be drawn from this data to Minoan culture and history? (4) What comparisons could be made to Mesopotamian glyptic?

Further Investigation of the Method of Manufacture of an Ancient Near Eastern Cast Glass Vessel

The purpose of this paper is to describe a further investigation into the method of manufacture of an important eighth–seventh century B.C. glass vase (Plates I a , II a ) from Syria or Assyria now in the Corning Museum collection. It is somewhat similar to the well known Sargon vase in the British Museum. In our initial study we focused on methods used to finish this cast glass vessel, particularly the drilled handles, the interior walls, the profiled bands and polished outer surface. In the present study we have again focused on the drilled handles in order to determine the type of drill bit, the type of drill, abrasive and lubricant. The reason for this particular emphasis was that several important questions in our initial study were left unresolved. In addition, a serendipitous finding and subsequent research in the field of ancient Egyptian lapidary offered new insights and working hypotheses.