Comparison in the use of dentures with atrophic mandibular ridge,
made by means of conventional and neutral zone techniques,
retained and not retained by 4 implants with
locator® attachments (pilot study).
DDS Koizume G. Roberto, DDS MS Rosas R. Patricia, DDS MS Obregon P. Alejandro
A rehabilitation with dentures in atrophic ridges, especially in the jaw, that meet stability and retention in function and meet the aesthetic and comfort expectations of the patient is one of the greatest challenges. On the one hand, the neutral zone has been shown to improve retention, stability and comfort in these cases. On the other hand, the treatment with implant-supported overdentures has registered a high level of satisfaction.
A 64 year-old female patient presents lower remaining teeth with mobility grade III 17 and 20 to 27. Extractions were performed and immediate dentures were placed. After that, the planning and placement of 4 implants for overdentures with Locator abutments was performed. One set of dentures will be made with neutral zone and another with conventional technique
Planning and placement of implants inside neutral zone.
The position and direction of the placement of the implants affect the function and aesthetics of the rehabilitation, so the rim obtained with the cameo surface in the neutral zone technique was duplicated and used like radiographic and surgical template, to ensure the position of implants and abutments into the neutral zone.
Two sets of dentures were performed, one by conventional technique and the other by neutral zone, which were initially used by the patient for a period of 6 weeks each without attachments activated then were used with the locator abutments activated for the same period of time.
Phonetics, swallowing, retention and stability tests were carried out and the necessary adjustments were made during the first week of use of each pair and chewing tests were carried out on the 2nd , 4th and 6th week with 4 peanuts asking the patient to deposit them in containers, at the time it was to be swallow to be sieved in 3 different sizes, this procedure was performed before and after activating the locator attachments in both techniques.
with out active Locator
The improvement of the stability and retention of the neutral zone technique in dentures placed in reabsorbed mandibular ridges compared with the conventional technique, without the assistance of implants was corroborated. Due to this, the ability to chew is also favored in the neutral zone technique as observed in the test.
When evaluating the phonetics there was no difference between the techniques, in terms of the need for adjustments (comfort) and aesthetics the neutral zone obtained better acceptance by the patient.
When activating the locator attachments there was no difference between the neutral zone and the conventional technique in any test.
Despite improving the retention and stability with the neutral zone, the patient prefers the activation of the locator attachments.