Purpose: This crossover study evaluated masticatory efficiency and masseter muscle activity of conventional dentures, implant-assisted overdentures, and fixed hybrid prostheses in patients with atrophied mandibles.
Materials and methods: Twenty edentulous patients with mandibular ridge atrophy received mandibular and maxillary conventional dentures (control, CD). Following three months adaptation period, four parallel implants were installed in the interforaminal region. In a random method, bar overdentures (BOD) or fixed hybrid prosthesis (FHP) was constructed for each patient. Chewing efficiency (in terms of variance of the hue, VOH) was estimated utilizing chewing gum and ViewGum software program. EMG of masseter muscles (in terms of amplitude) was completed while clenching without food and clenching on soft and hard foods or without food. Measurements were performed three months after wearing the following prostheses: CD, BOD, and FHP.
Results: BOD and FHP recorded significantly lower VOH than conventional dentures. No difference in VOH between BOD and FHP. The BOD and FHP exhibited significantly higher amplitude than the CD group. No significant differences amplitude between BOD and FHP prostheses were noted for all clenchings. Clenching on the hard food achieved the highest amplitude and clenching with no foods achieved the lowest amplitude.
Conclusion: Within the scope of this trial, it could be concluded that both fixed hybrid prosthesis (FHP) and long bar overdentures (BOD) supported by 4 parallel interforaminal implants with distal cantilevers up to first molar teeth are recommended treatment modalities in patients with atrophied mandibular ridges as both improved chewing efficiency and EMG compared conventional denture.