Actually, this is a “both yes and no” question.
First the “no.” The Holy Sacrifice of the Mass is the same whether celebrated by a bishop or a priest. It is not more holy, nor is Christ more present.
Then the “yes.” A presbyter (priest) is one who represents the bishop, who is the successor to the Apostles. In that sense, when the celebrant is a bishop, especially the diocesan bishop, the Mass is more special because it expresses the apostolicity and unity of the Church; it is a better expression of the Church Catholic.
Here is a quote from the Vatican II Constitution
Sacrosanctum Concilium
Please note that when these particular paragraphs read “the bishop” they refer to the bishop of the diocese (ie the Ordinary); still a bishop (auxiliary or emeritus etc.) is a successor to the Apostles in a way that a presbyter is not.
- The bishop is to be considered as the high priest of his flock, from whom the life in Christ of his faithful is in some way derived and dependent.
Therefore all should hold in great esteem the liturgical life of the diocese centered around the bishop, especially in his cathedral church;
they must be convinced that the pre-eminent manifestation of the Church consists in the full active participation of all God’s holy people in these liturgical celebrations, especially in the same eucharist, **in a single prayer, at one altar, at which there presides the bishop surrounded by his college of priests **and by his ministers [35].
- But because it is impossible for the bishop always and everywhere to preside over the whole flock in his Church, he cannot do other than establish lesser groupings of the faithful. Among these the parishes, set up locally under a pastor who takes the place of the bishop, are the most important: for in some manner they represent the visible Church constituted throughout the world.
And therefore the liturgical life of the parish and its relationship to the bishop must be fostered theoretically and practically among the faithful and clergy; efforts also must be made to encourage a sense of community within the parish, above all in the common celebration of the Sunday Mass.
Here is the important point: We should remember that when the bishop (indeed any bishop) presides, the Mass is not more special because of his celebrity status (yes, bishops are more rare than priests, bishops wear mitres and pectoral crosses) but is more special
because of his status as Successor to the Apostles.